EPA-450/3-75-048 by R. M. Patterson, R. D. Wang, and F. A. Record GCA Corporation GCA/Technology Division Bedford, Massachusetts 01730 Contract No. 68-02-0041 Task 18 EPA Project Officer: Charles C. Masser Prepared for ENVIRONMENTAL PROTECTION AGENCY Office of Air and Waste Management Office of Air Quality Planning and Standards Research Triangle Park, North Carolina 27711 December 1974 ------- "This report has been reviewed by the Office of Research and Monitoring, EPA, and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of the Environmental Protection Agency, nor does mention of trade names or commercial products constitute endorsement or recommendation for use." ------- ABSTRACT This report describes a methodology for performing emission inventories at airports, with specific focus on the airports in the St. Louis AQCR. This work was performed in support of EPA's RAPS program. Within the basic methodology, three submethodologies are presented corresponding to municipal, military, and civilian airports. Data col- lection and handling requirements are discussed, and data for the air- ports in the St. Louis AQCR are presented. The sensitivity of emission estimates to improved knowledge of data inputs is discussed. ii ------- CONTENTS Page Abstract ii List of Figures iv List of Tables v Sections I Introduction 1 II Emission Inventory Needs for RAPS 3 III Factors Contributing to Airport Emissions 5 IV Levels of Emission Inventory Detail 18 V Emission Estimation Methodology for Lambert Field 22 VI Scott Air Force Base 51 VII Civilian Airports 59 VIII Methodology Summary 86 IX Improving Estimates 98 X References 100 iii ------- FIGURES No. 1 Interacting Factors Affecting Emissions Production 7 at a Municipal Airport 2 Hourly Percent of Total Daily LTD Volume for a Typical 9 Municipal Airport 3 Interacting Factors Affecting Emissions Production at 12 a Civilian Airport 4 Lambert - St. Louis International Airport 34 5 Runway Layout and Grid Element Overlay for Scott AFB 54 6 Diagram of Civic Memorial Airport Showing Grid Element 63 Overlay 7 Diagram of Spirit of St. Louis Airport showing grid e 65 element overlay 8 Diagram of Bi-State Parks Airport Showing Grid Element 67 Overlay 9 Diagram of St. Clair Airport Showing Grid Element 69 Overlay 10 Diagram of Creve Coeur Airport Showing Grid Element 71 Overlay 11 Diagram of Sparta Airport - Grid Element 1633 73 12 Diagram of Wentzville Airport - Grid Element 76 75 13 Diagram of Arrowhead Airport - Grid Element 2102 76 14 Diagram of St. Charles Airport - Grid Element 241 77 15 Diagram of Weiss Airport - Grid Element 2161 78 16 Diagram of Festus Airport - Grid Element 467 79 17 Diagram of St. Charles Smartt Airport - Grid Element 242 80 18 Diagram of Highland Airport - Grid Element 1709 81 19 Diagram of Gebhardt Airport - Grid Element 883 82 20 Diagram of Greenville Airport - Grid Element 1815 83 IV ------- TABLES No. 1 Aircraft Operating Modes 6 2 Aircraft Classifications and Representative Aircraft 10 3 Service Vehicles Used at a Municipal Airport 15 4 Percent Emissions Contribution by Source at O'Hare 21 Airport - 1970 5 FAA Classification of Daily Air Traffic Operations 24 6 Average Hourly Air Traffic Volumes at Lambert Field, 24 St. Louis, for May and November, 1972 7 Monthly Air Traffic at Lambert Field, St. Louis, for 26 December 1972 and January - November 1973 8 Air Traffic Volumes by Day of Week at Lambert Field, 26 St. Louis, for December 1972 and January - November 1973 9 Percent of Total Annual Air Traffic by Month at Lambert 27 Field 10 Percent of Total Air Traffic by Day of Week for Lambert 27 Field, St. Louis 11 Percent of Total Daily Movements by Hour at Lambert 28 Field 12 Percent of Departures and Arrivals by Air Carrier 30 Traffic by Hour of the Day 13 Operating Modes for Each Grid by Active Runway at 32 Lambert Field, St. Louis 14 Times in Mode by Grid by Mode for Air Traffic Using 36 Runway 30L (seconds) 15 Times in Mode by Grid by Mode for Air Traffic Using 37 Runway 12R (seconds) 16 Times in Mode by Grid by Mode for Air Traffic Using 38 Runway 30R (seconds) 17 Times in Mode by Grid by Mode for Air Traffic Using 38 Runway 12L (seconds) ------- TABLES No. 18 Times in Mode by Grid by Mode for Air Traffic Using 39 Runway 35 (seconds) 19 Times in Mode by Grid by Mode for Air Traffic Using 39 Runway 17 (seconds) 20 Times in Mode by Grid by Mode for Air Traffic Using 40 Runway 6 (seconds) 21 Times in Mode by Grid by Mode for Air Traffic Using 40 Runway 24 (seconds) 22 Aircraft and Engine Volumes for Lambert Field, St. Louis 41 23 Emission Factors by Engine Type and Mode for Air 42 Carriers (kg/hr) 24 Composite Emission Factors for Air Taxi, General 43 Aviation, and Military Aircraft at Lambert Field (kg/hr) 25 Service Times of Aircraft Ground Service Vehicles 45 26 Ground Service Vehicle Fuel Consumption Rates 47 27 Ground Service Vehicle Emission Factors 48 28 Ninety-Four Year Average High, Medium, and Low 48 Temperatures for St. Louis (°F) 29 Working Loss Factors for the Three Time Periods for 50 Each Month 30 Five-Month Air Traffic Volumes, Means, and Standard 51 Deviations at Scott AFB, 1973 - 1974 31 Percent of Air Traffic by Day of Week at Scott AFB 52 32 Percent of Air Traffic by Hour at Scott AFB 53 33 Time in Mode by Grid and Mode for Aircraft Using Runway 55 13, Scott AFB (seconds) 34 Time in Mode by Grid and Mode for Aircraft Using Runway 55 31, Scott AFB (seconds) 35 Emission Factors for Scott AFB (kg/hr) 56 vi ------- TABLES No. 36 Ground Service Vehicles Used at Scott AFB 57 37 Percent of Air Traffic by Month at Civic Memorial 60 Airport 38 Percent of Air Traffic by Day of Week at Civic 60 Memorial Airport 39 Percent of Air Traffic by Hour of the Day at Civic 61 Memorial Airport 40 Annual Air Traffic Volumes at Civilian Airports in the 61 St. Louis AQCR 41 Operating Modes for Each Grid by Active Runway at Civic 64 Memorial Airport 42 Operating Modes for Each Grid by Active Runway at 66 Spirit of St. Louis Airport 43 Key Operating Modes for Each Grid for Each Runway at 68 Bi-State Parks Airport 44 Key Operating Modes for Each Grid for Each Runway at 70 St. Clair Airport 45 Key Operating Modes for Each Grid for Each Runway at 72 Creve Coeur Airport 46 General Aviation Airports Contained in One Grid, 74 St. Louis 47 Times in Mode for General Aviation Aircraft at Civilian 84 Airports 48 Annual Volumes of Fuel Sales at the General Aviation 84 Airports VII ------- SECTION I INTRODUCTION Under the charges of the Clean Air Act of 1970, the Environmental Pro- tection Agency is assisting state and local pollution control agencies in developing implementation strategies to meet the established air quality standards. A basic premise of these efforts is that operation- ally a cause and effect relationship between pollution sources and air quality can be accurately specified. The EFA is conducting the Regional Air Pollution Study (RAPS) in St. Louis to determine the current relia- bility of this premise, and to provide for improvements where accuracy is less than adequate. To achieve this goal, RAPS will engage in extensive analysis of the at- mospheric dispersion and transformation process modeling links between emissions and air pollution levels. The cause and effect data required to analyze these modeling links include detailed temporal and spatial emission inventories; atmospheric data such as wind fields and tempera- ture profiles for dispersion calculations, and insolation data for transformation process modeling; and air pollutant concentration data against which modeling results will be compared. A crucial phase of this program is the adequate and accurate specifica- tion of emission inventories at least to the level of detail engaged by the models - the results of these deterministic links can be no more comprehensive and consistent than the initial input values. Emissions inventories have been made by county in the St. Louis Air Quality Con- trol Region according to the Nation Emissions Data System (NEDS). Air- ------- Aircraft operations were surveyed for yearly landing and takeoff cycle volumes for each type of airport, and a single emission factor based on type of airport was applied to each to calculate annual emissions. The spatial and temporal detail involved is insufficient for uses other than trend estimates of emissions. This report describes techniques for inventorying airport emissions from air- craft and ground support vehicles and processes as an aid to achieve the RAPS goals. ------- SECTION II EMISSION INVENTORY NEEDS FOR RAPS The St. Louis Interstate Air Quality Control Region is subdivided into a grid system for the RAPS study. The smallest grid side is 1 km, so that an airport may not be wholly enclosed in a single grid. This, and the requirement of hourly average emissions data, dictates the develop- ment of more spatially and temporally detailed emission inventory data and methodologies than are currently available. This report describes the available data and techniques and outlines further refinements of methodologies for inventorying airport emissions. The sources involved include aircraft operations and engine maintenance testing, ground support vehicles, and fuel storage and handling. For these sources there needs to be described: emission rate emission location emission duration The task of developing and analyzing emission inventory methodologies for these sources can be divided into three sub-tasks based on the type of airport in question; that is, inventories for municipal, civilian, and military airports. The methods for inventorying each are similar and reduce to finding the three factors listed above. However, the types of sources and their significance is a function of the type of airport. The municipal airport has principally commercial jets, ground support vehicles for servicing and fueling these aircraft, jet fuel handling and storage, and testing of jet engines. Civil airports pri- marily carry private and charter piston aircraft, ground support to the ------- extent of fueling trucks (absent at the smaller airports), gasoline storage and handling (with some jet fuel at larger airports), and test- ing of piston engines. The military airport operations consist mainly of jet aircraft, fueling trucks, jet fuel handling and storage, and jet engine testing. ------- SECTION III FACTORS CONTRIBUTING TO AIRPORT EMISSIONS The purpose of this section is to outline the factors contributing to airport emissions and to discuss how they are interrelated. This is presented to provide an overview of the inventory problem for airports and to provide a basis from which to examine alternative levels of inventory detail. The factors contributing to airport emissions are those involved with the previously listed sources of aircraft operation, ground support vehicles, fuel storage and handling, and engine maintenance testing. These factors are discussed for each type of airport in the following sections. FACTORS AFFECTING FLIGHT OPERATION EMISSIONS Flight operations consist of the modes listed in Table 1. To determine emissions, two basic factors must be known: (1) the time spent in each mode, and (2) the emission rate for each mode. The interacting factors determining these basic factors are outlined below. I Municipal Airport Flight Operations Figure 1 is a diagram showing the interactions of factors affecting emission production at a municipal airport. These will be sorted accord- ing to significance of contribution and availability of information when levels of emission inventory detail and relative emission contribu- tions are discussed. ------- Table 1. AIRCRAFT OPERATING MODES2 Mode Engine operating time included in mode Taxi Idle Land ing Takeoff Approach Climb-out Transit times between ramp and apron, apron and runway and time required for turning and alignment between taxiway and runway. Push back from gate; waiting for signal to begin taxiing; waiting at taxiway intersec- tions; runway queuing; gate queuing. Touchdown to beginning of taxi on taxiway. After alignment with runway to liftoff. 3000 ft altitude to touchdown. Liftoff to 3000 ft altitude. ------- TIME OF DAY DAY OF WEEK MONTH PASSENGER DEMAND VOLUME LTD VOLUME AIRCRAFT MIX QUEUING TIME IN MODE EMISSIONS FREIGHT DEMAND ORIGIN-DESTINATION REQUIREMENTS AIRLINE TERMINAL LOCATION TERMINAL- RUNWAY DISTANCE SPECIAL LTO PROCEDURES AND PATHS POWER REQUIREMENTS EMISSIONS PER TIME IN MODE Figure 1. Interacting factors affecting emissions production at a municipal airport ------- The major impetus to flight operations is the passenger demand volume. Fluctuations in demand volume occur with time of day, the day of the week, and the month. Figure 2 shows the hourly percent of the total LTO volume for a typical airport. Airline schedules and schedule changes reflect these fluctuations. Freight demands are shown in Figure 1 as being secondary to passenger demands as cargo needs are usually accom- modated on passenger flights. Landing and takeoff cycle volume is then determined by passenger demand. Origin-destination requirements and LTO volume determine the mix of equipment, which in turn feeds back to LTO volume. Short, low passenger demand trips will be made by medium and short range aircraft; longer, high demand trips will use long range and jumbo jets. The aircraft classes and representative aircraft within each class are listed in Table 2. If the LTO volume is greater than some number characteristic of the air- port and runway in use queues will form. The EPA report, "Air Pollu- 2 tion Impact Methodology for Airports," (APTD-1470) recommends adding extra idle time due to queuing as T = (N-30)/10 when the LTO volume exceeds 30 per hour. T is the time queued in minutes and N is the LTO volume. This relationship assumes the use of two parallel runways and is empirically based on experience at Chicago's O'Hare airport. For more nearly accurate idle mode emission calculations, similar relation- ships should be determined for St. Louis, since in addition to LTO volumes, queue times can depend on airport configuration and runway in use, approach path radio aids, weather, and even the air traffic con- troller. The LTO volume affects queuing which affects the time spent in the idle mode. Other "times in modes" are influenced by additional factors as shown in Figure 1. ------- PERCENTAGE OF TOTAL DAILY MOVEMENTS hrj 5 S ft> ffi o rt C *O I-1 H- < O P3 X> l-« fD i-i S o e CD P p H- rt o P- O PJ rt H- OJ XI O CL i-i 93 H O < S1 n CO OO 00 C7 T ± o , C" O vj ... 00 Oi O ^ E ------- Table 2. AIRCRAFT CLASSIFICATIONS AND REPRESENTATIVE AIRCRAFT" Aircraft class Representative aircraft Jumbo jet Long-range jet Medium-range jet Air carrier turboprop Business jet General aviation turboprop General aviation piston Piston transport Helicopter Military turboprop Military jet Military piston Boeing 747 Lockheed L-1011 McDonald Douglas DC-10 Boeing 707 McDonald Douglas DC-8 Boeing 727 Boeing 737 McDonald Douglas DC-9 Convair 580 Electra L-188 Fairchild Killer FH-227 Gates Learjet Lockheed Jetstar Cessna 210 Piper 32-300 Douglas DC-6 Sikorksy S-61 Vertol 107 10 ------- Meteorological conditions of wind direction and visibility determine the runway in use. Generally, it will be the longest runway or the one most nearly parallel to wind direction, although low visibility or night flight might require the use of an instrument landing system equipped or lighted runway which does not give the best alignment with wind direction. The terminal location and the runway in use determine the time spent in taxi mode before takeoff and after landing. Time in takeoff and landing modes is affected by the component of wind velocity parallel to the runway and by the temperature as well as type of aircraft. Takeoff and landing times are shorter the higher the wind speed and the lower the temperature. These times become longer as the aircraft carries more mass to be accelerated and lifted, or decelerated after landing. The same factors affect climbout and approach, with potential modifica- tions if nearby populated areas require special noise reduction pro- cedures and flight paths. These may include techniques such as climbing at reduced power and immediate turns away densely populated areas. After the time spent in the different modes are determined they can be multiplied by the modal emission rates to calculate emissions. The emission rates depend basically on power requirements and engine type, which are in turn related to passenger and freight volume, amount of fuel carried for origin-destination requirements, weather, and special LTO procedures. Civilian Airport Flight Operations Figure 3 is a diagram of the interacting factors involved in emission production at a civilian airport. Weather is a dominant factor in civilian flight operations. The level of activity falls as the weather deteriorates, since much of the flying done is for instruction and pleasure, and since pilot qualifications often exclude flying during 11 ------- WEATHER TYPE OF USE ORIGIN- DESTINATION REQUIREMENTS TIME OF DAY DAY OF WEEK MONTH OF YEAR NUMBER OF PASSENGERS EMISSIONS PER TIME IN MODE EMISSIONS Figure 3. Interacting factors affecting emissions production at a civilian airport 12 ------- inclement weather. Further, the airport may not be equipped with the radio navigation aids needed for foul weather flying. The traffic volume also varies with time of day, day of week, and month. It is generally heavier in the evening, on weekends, and in the summer when private pilots have the time and weather offers more incentive to fly. These factors determine the air traffic volume and, to some extent, the mix. Commercial charter and business flights are less affected by weather than private flights. When there is a large percentage of private flights the mix will have a greater percentage of small, single engine aircraft. Time in mode is affected by the same factors as at the municipal air- port, only in this case the aircraft are at ramp or tie-down locations. Aircraft rental, instruction, and charter companies generally have a specific portion of the ramp area for their use which is rented from the airport authority. These locations can be determined from a visit to the airport. Time in mode, and also power requirements, are further affected by the number of passengers, especially in light, two or four-place planes where .passenger weight is a significant fraction of aircraft weight. Clitnbout time is reduced with fewer passengers, reducing time in this mode, while approach time is increased because of reduced downward weighting force. When emission rates as functions of mode and power requirements are known, they can be multiplied by the times in the various modes to find emissions. 13 ------- Military Airport Flight Operations These operations are influenced by the factors common to all airport operations; however, they are not dependent on passenger demands, as at the municipal airport, nor are they strongly affected by weather, as for civilian flights. The level of activity is determined mainly by training, proficiency, and defense requirements. Weather determines the runway used and taxi times. FACTORS AFFECTING GROUND SUPPORT VEHICLE EMISSIONS Municipal Airport The municipal airport has by far the most ground service vehicle opera- tions. A listing of the types of service vehicles is given in Table 3. The extent of use of each vehicle is directly related to LTO volume and aircraft mix. Emissions can be calculated from published data on service times and emission rates. Emissions from service vehicle travel around the airport can be found knowing the airport layout, the activity, and the proper emission factors. Civilian Airports Service vehicles at civilian airports are almost exclusively fueling trucks, and even these may be absent at the smaller airports. Other support vehicles may include tractors, etc. for grass cutting and snow removal. Military Airport Service vehicles at the military airport also include fueling trucks and many of the vehicles found at municipal airports. Emissions from these sources are dependent on flight activity. 14 ------- Table 3. SERVICE VEHICLES USED AT A MUNICIPAL AIRPORT2 Vehicle 1. Tractor 2. Belt loader 3. Container loader 4. Cabin service 5. Lavatory truck 6. Water truck 7. Food truck 8. Fuel truck 9. Tow tractor 10. Conditioner 11. Airstart Transporting engine Diesel power unit 12. Ground power unit Transporting engine Gasoline power unit Diesel power unit 13. Transporter 15 ------- FUEL HANDLING AND STORAGE EMISSIONS These emissions are of two types: (1) working losses, and (2) breathing losses. The former type occurs when vapors in fuel tanks are displaced during fueling, and when there is spillage and evaporation. The latter type is due to diurnal temperature variations, wind speeds, and fuel vapor pressure among other factors. It may be controlled by tank vapor recovery systems. Municipal Airport By far the largest use is of jet fuel with a much smaller volume of gasoline used for service vehicles and piston aircraft. Actual volumes of each are a function of LTO activity, passenger volumes, and origin- destination distances. Civilian Airport Here, gasoline comprises the larger volume of fuel use. Jet fuel is available at the larger airports. Gasolines of different octane ratings at these airports will have slightly different emission characteristics because of volatility differences. Actual use will be determined by LTO activity and the factors affecting it. Military Airport Jet fuel comprises the larger use for military airport operations. Gaso- line is used for service vehicles. ENGINE MAINTENANCE TESTING The emissions from this source depend on the test cycle power settings and times spent at each setting for the various types of engines. The municipal and military airports will handle mostly jet engine testing, 16 ------- while the civilian airports will test piston engines. Emissions from this source at the smaller civilian airports will be negligible, if not non-existent. 17 ------- SECTION IV LEVELS OF EMISSION INVENTORY DETAIL The ideal emissions inventory would consider all the interrelating fac- tors described in Section III. Of course, the time and economic costs would be prohibitive. The purpose of this study is to consider altern- ative levels of detail for making inventories on a "cost-benefit" basis, determining the significance of emissions sources and the sensitivity of an inventory in.return for added data collection and analysis efforts. In this section, levels of detail are outlined with comments on efforts and benefits. EMISSIONS INVENTORY FROM PUBLISHED DATA Features: NEDS data on annual LTO volumes by airport type and county Uses average emission factor for LTO cycle based on type of airport Annual LTO activity data available from FAA Time resolution - annual average Spatial resolution - countywide area source Comments: Easily calculated from readily available data Insufficient resolution and specificity by source. 18 ------- TYPE OF AIRCRAFT DETAIL Features: Emission factor for type of aircraft Percent of total LTO's for type of aircraft Emission factor for service vehicle use by type of aircraft ' Emission factor for fuel handling and storage by aircraft mix and total LTO's Emission factor for maintenance testing by type of aircraft Data available from FAA, airport records, airline schedules Time resolution - by type of data collected Spatial resolution - by source locations at airport Comments: 1 More extensive data collection effort Easily calculated once necessary data are known Time resolution variable TIME-IN-MODE DETAIL Features: Emission factors by mode required Average times in mode required Comments: Average time in mode data available from EPA publication "An Air Pollution Impact Methodology for Airports - Phase I," (APTD-1470) No additional data collection needed Relatively little added effort over type of aircraft detail 19 ------- HOURLY EMISSION ESTIMATES Features: LTO activity by time of day, day of week, month, type of aircraft Data available from airline schedules, airport records, FAA Comments: Extensive effort required for data collection and analysis over time-in-mode detail Hourly resolution for aircraft operations, support vehicles, fuel handling REFINED HOURLY EMISSIONS ESTIMATES Features: To include meteorological effects, special LTO procedures, aircraft loading, terminal-runway distances, queuing Comments: Long-term, extensive effort required for data collection Computer analysis of data Degree of refinement not initially required RELATIVE EMISSIONS CONTRIBUTIONS BY SOURCE AT AIRPORTS Table 4 shows the relative emissions contributions of the airport sources at O'Hare airport in 1970. Aircraft operations account for well over 60 percent of carbon monoxide and hydrocarbon emissions, and about 90 percent of these emissions occurs during taxi and idle modes. This indicates a good sensitivity return for improved data on time in mode and emission rates for these modes. 20 ------- Table 4. PERCENT EMISSIONS CONTRIBUTION BY SOURCE AT O'HARE AIRPCRT - 1970 Source Aircraft Service vehicles Fuel handling CO 69 31 0 HC 79 13 8 NOX 86 14 0 Particulate 96 4 0 Aircraft operations contribute 86 percent to total NO emissions, X indicating good leverage from improved information on the factors involved. Most of these emissions occur during the high power operations of takeoff and climbout. 21 ------- SECTION V EMISSION ESTIMATION METHODOLOGY FOR LAMBERT FIELD This section and the following two sections describe the hourly emission estimation techniques. This section applies to Lambert Field, the next one applies to Scott AFB, and Section VII describes the methodology for the civilian airports. The three types of airports are discussed separately, since data availability and the complexity of the required methodology is different for each. Four emission sources are included in the methdologies: Aircraft flight operations Ground service vehicles Fuel handling and storage Engine testing and maintenance. EMISSIONS FROM AIRCRAFT FLIGHT OPERATIONS To estimate hourly emissions from aircraft flight operations five parameters must be known: Temporal activity patterns Spatial activity patterns Percent volume distribution of aircraft types Time spent in the different operating modes Emission factors. 22 ------- The following sections discuss the availability of data for each of these five parameters, and the use of these data in a methodology for emission estimation. Temporal Activity Patterns Ideally, hourly landing and takeoff volumes and type of equipment would be known for the best predictions of emissions. However, this informa- tion is not compiled and estimates must be made from available data. For Lambert Field there are three sources of data: « Federal Aviation Administration Air Traffic Control Tower, Mr. Jerome C. Moonier Lambert Field, Manager's Office, Mr. Arthur K. Muchmore, Assistant Airport Manager, Operations and Maintenance Official Airline Guide listings for air carrier traffic at St. Louis The FAA maintains daily totals of traffic volumes under the classifica- tions shown in Table 5. Local traffic has its origin and destination at Lambert, and it mainly involves "touch and go" landing and takeoff practice. Itinerant operations have their origin or destination at another airport. These classifications are further divided for itinerant traffic into air carrier, air taxi, general aviation, and military categories. For local operations they are subdivided into civilian and military categories. The FAA also compiles average hourly activity totals for May and November. The November totals are presented in Table 6. The airport manager's office receives its flight activity information from the FAA in the form described. This office' is an alternative source of this information. 23 ------- Table 5. FAA CLASSIFICATION OF DAILY AIR TRAFFIC OPERATIONS DAY Itinerant air traffic AIR AIR CARRIER TAXI GENERAL AVIATION MILITARY TOTAL Local air traffic CIVIL MILITARY TOTAL Total air traffic Table 6. AVERAGE HOURLY AIR TRAFFIC VOLUMES AT LAMBERT FIELD, ST. LOUIS, FOR MAY AND NOVEMBER, 1972 Hour 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900- ] 000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 Volume 12 11 10 3 4 5 13 36 55 64 68 66 64 66 65 57 67 64 50 43 40 26 30 13 24 ------- The Official Airline Guide lists flight schedules semi-monthly for the air carriers. These listings show scheduled departure and arrival times and type of aircraft used. Scheduled flight activity to St. Louis is listed in one section of the Guide, while flights from St. Louis to other cities are listed under the destination city headings. Table 6 lists hourly totals of flight activity at Lambert Field. To complete the temporal data, the total volumes by month and by the day of the week for the four aircraft categories are given in Tables 7 and 8. The itinerant and local volumes have been combined for both general aviation and military flights in these Tables. In order to prepare a methodology for estimating emissions, the volumes given in Tables 6, 7, and 8 were converted to percentages totaling 100 percent for each category of aircraft. The computed percentages for monthly, daily, and hourly air traffic are given in Tables 9, 10, and 11. To compute the volume of traffic for category i for a given hour, day, and month we start from the relationship: M. , ' D. H. V. = . 1 (ODm) (106) / where i indicates the category (e.g. air carrier), A. is the annual volume, and M., D., and H. are the percents of the annual volume for the month, day, and hour of interest. The factor OD is the average m occurrence of the day of the week for the month. It equals 4.43 for months having 31 days, 4.29 for 30 day months, and 4 for February (4.14 in a leap year). The factor of 10 converts the percentages to decimals This relationship can be entered at any point. For example, if the monthly total is known, 25 ------- Table 7. MONTHLY AIR TRAFFIC AT LAMBERT FIELD, ST. LOUIS, FOR DECEMBER 1972 AND JANUARY - NOVEMBER 1973 Month January February March April May June July August September October November December Category Total Air carrier 16,006 14,316 15,655 13,955 12,236 12,363 15,703 16,721 15,934 16,658 11,004 15,234 175,785 Air taxi 1,985 1,744 2,052 2,078 . 2,606 2,648 2,492 2,812 2,474 2,724 2,488 1,590 27,693 General aviation 9,112 8,957 9,300 11,305 13,106 12,618 12,137 12,420 10,509 11,985 11,110 6,691 129,250 Military 1,008 1,013 1,071 1,363 1,576 1,293 963 1,187 1,106 1,353 878 861 13,672 Total 28,111 26,030 28,078 28,701 29,524 28,922 31,295 33,140 30,023 32,720 25,480 24,376 346,400 Table 8. AIR TRAFFIC VOLUMES BY DAY OF WEEK AT LAMBERT FIELD, ST. LOUIS, FOR DECEMBER 1972 AND JANUARY - NOVEMBER 1973 Day Sunday Monday Tuesday Wednesday Thursday Friday Saturday Category Total Air carrier 23,385 25,037 25,499 25,965 26,259 26,718 22,922 175,785 Air taxi 1,907 3,229 4,801 5,115 5,040 5,280 2,321 27,693 General aviation 15,851 15,369 18,424 20,772 21,326 20,499 17,009 129,250 Military 1,096 1,219 2,266 2,532 2,390 2,505 1,664 13,672 Total 42,239 44,854 50,990 54,384 55,015 55,002 43,916 346,400 26 ------- Table 9. PERCENT OF TOTAL ANNUAL AIR TRAFFIC BY MONTH AT LAMBERT FIELD Month January February March April May June July August September October November December Air carrier 9.11 8.14 8.91 7.94 6.96 7.03 8.93 9.51 9.06 9.48 6.26 8.67 Air taxi 7.17 6.30 7.41 7.50 9.41 9.56 9.00 10.15 8.93 9.84 8.98 5.74 General aviation 7.05 6.93 7.20 8.75 10.14 9.76 9.39 9.61 8.13 9.27 8.60 5.18 Military 7.37 7.41 7.83 9.97 11.53 9.46 7.04 8.68 8.09 9.90 6.42 6.30 Total 8.18 7.57 8.16 8.07 8.52 8.38 8.98 9.64 8.73 9.52 7.40 6.86 Table 10. PERCENT OF TOTAL AIR TRAFFIC BY DAY OF WEEK FOR LAMBERT FIELD, ST. LOUIS Day Sunday Monday Tuesday Wednesday Thursday Friday Saturday Air carrier 13.30 14.24 14.51 14.77 14.94 15.20 13.04 Air taxi 6.89 11.66 17.34 18.47 18.20 19.07 8.38 General aviation 12.26 11.89 14.25 16.07 16.50 15.86 13.16 Military 8.02 8.92 16.57 18.52 17.48 18.32 12.17 Total 12.19 12.95 14.72 15.70 15.88 15.88 12.68 27 ------- Table 11. PERCENT OF TOTAL DAILY MOVEMENTS BY HOUR AT LAMBERT FIELD Hour 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 Air carrier 1.15 1.00 1.00 0.26 0.42 0.42 1.36 3.67 6.02 6.81 6.97 6.86 6.71 7.12 6.60 5.92 7.23 7.18 5.97 5.40 4.71 3.04 2.88 1.31 Air taxi 2.05 1.33 1.33 0.24 0.24 0.00 0.97 2.54 4.83 5.92 6.88 7.49 6.52 6.88 9.42 8.33 6.76 6.52 5.43 4.35 4.23 3.62 2.66 1.45 General aviation 2.05 1.33 1.33 0.24 0.24 0.00 0.97 2.54 4.83 5.92 6.88 7.49 6.52 6.88 9.42 8.33 6.76 6.52 5.43 4.35 4.23 3.62 2.66 1.45 Military 2.05 1.33 1.33 0.24 0.24 0.00 0.97 2.54 4.83 5.92 6.88 7.49 6.52 6.88 9.42 8.33 6.76 6.52 5.43 4.35 4.23 3.62 2.66 1.45 28 ------- M. D. H. v- = ~ Lr1 1 (ODm) (10^) where M. is the monthly total volume of aircraft category i. Suppose it is required to estimate the air carrier activity between / 10 am. and 11 am. on a Wednesday in June. The arrival total A. = 175,785; from Table 9, M. = 7.03; D. = 14.77 from Table 10, and H. = 6.97 from Table 11. Hence v = (175,785) (7.03) (14.77) (6.97) 1 (4.29) (106) = 30 air carrier movements (takeoff plus landing). This method assumes equal numbers of landings and takeoffs, and also that the distribution of activity by month, day of the week, and hour remains constant from year to year. The exact landing and takeoff split by hour for air carriers can be extracted from the Official Airline Guide. This has been done for "average" day, and the results are shown in Table 12. For other categories it is assumed that half the movements are takeoffs and half are landings. The relationship for calculating hourly volumes can be entered at any point for which a volume is known. The actual volume for the year, month, or day of interest can be used when making an emission inventory retrospectively. These data are available from the FAA Air Traffic Control Tower at Lambert. The percent volumes presented in Tables 9, 10 and 11 are for December 1972 and January-November 1973. In future years the latest figures could be used to revise these tables either by replacement, or by averaging. The former revision of replacement may become especially 29 ------- Table 12. PERCENT OF DEPARTURES AND ARRIVALS FOR AIR CARRIER TRAFFIC BY HOUR OF THE DAY4 Hour 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 Departures (%) 25.00 66.67 100.00 0 0 100.00 33.33 58.33 52.94 37.84 60.53 40.63 43.59 32.26 62.86 32.00 42.11 50.00 40.63 51.43 41.67 15.38 20.00 57.14 Arrivals (%) 75.00 33.33 0 100.00 0 0 66.67 41.67 47.06 62.16 39.47 59.37 56.41 67.74 37.14 68.00 57.89 50.00 59.37 48.57 58.33 84.62 80.00 42.86 30 ------- important if economic or other factors change the distribution as well as the total volume of air traffic. Spatial Patterns of Aircraft Flight Activity Aircraft flight activity consists of the six modes described in Table 1. These modes occur at different locations on the airport, and the emis- sions estimates must reflect this spatial variation. Lambert Field lies in eight grid elements of 1 kilometer squared according to the grid network designed for RAPS. Table 13 displays the grid numbers, the grid coordinates, and the aircraft operations in each grid according to the runway being used. Figure 4 shows the grids overlaid on the airport. No grids are listed for climbout or approach; these are listed later with times in mode. Lambert Field requests that aircraft maintain a constant heading away from or towards the runway when flying below 1500 feet. The approach glide path is about 2.5 or 3 degrees, so an approach heading is maintained within a distance of about 5 miles from the air- port. The FAA indicates good compliance with this request. Above 1500 feet the aircraft may fly in any direction. As an example, consider the emissions from the hourly volume of 30 air carrier movements. For the 1000-1100 hour, approximately 60 percent of these aircraft are departing. Generally these aircraft will move from the terminal area to the runway by the most direct taxiway when depart- ing, and they will move from the runway to the terminal area by the shortest taxi distance after landing. In this example, it is assumed that runway 30L is the active runway. Referring to Figure 4, two thirds of the terminal area, or ramp, is in grid 523, while the other third is in grid 492. Aircraft will taxi out to take off in grids 492, 523, and 559, and take off in grids 560, 523, and 559. (See Table 13.) Of the 18 aircraft taking off, 12 will have idle mode emissions in grid 523, and 6 will emit during idle in grid 492. The simplest method of dis- tributing the taxi and takeoff emissions would be to divide them equally 31 ------- Table 13. OPERATING MODES FOR EACH GRID BY ACTIVE RUNWAY AT LAMBERT FIELD, ST. LOUIS Runway SOL 3 OR 12R 12L 35 17 Grid 560 559 523 493 492 452 560 524 523 493 492 452 560 523 493 492 452 560 524 523 493 492 524 523 493 524 523 493 X-Coord 4291 4290 4291 4292 4291 4292 4292 Y-Coord 730 730 729 728 728 727 729 Size 1 1 1 1 1 1 1 1 1 1 1 1 Idle X X X X X X X X X X X X X X X X Taxi X X X X X X X X X X X X X X X X X X X X X Takeoff X X X X X X X X X X X X X X X X X X X Climbout s Approach Landing X X X X X X X X X X X X tf k X X X X X X X Taxi X X X X X X X X X X X X X X X ------- Table 13 (continued). OPERATING MODES FOR EACH GRID BY ACTIVE RUNWAY AT LAMBERT FIELD, / ST. LOUIS Runway 6 24 Grid 524 523 493 492 452 451 524 523 493 492 451 X-Coord 4291 Y-Coord 727 Size Idle X X X X X X X Taxi X X X X X X X X X Takeoff X X X X X Climbout Approach Land ing X X X X X Taxi X X X X X X OJ t-O ------- ELEVATION -3'89 ' MSL REVISED-3/32/72/68 REFLECTOR 30OO FROM END #559 Figure 4. Lambert - St. Louis International Airport ------- among the grids involved. A more rafined yet still simple method would be weight them according to the percent of the total taxi or takeoff time spent in each grid. This method is described here. Table 14 shows the times in mode in each grid for air carriers taxiing to and taking off from runway 30L. To calculate emissions for each grid, the idle emissions are added to grids 492 and 523 for the six and 12 aircraft, respectively, the taxi emissions are distributed by the times in Table 14 for the six aircraft starting from grid 492 and the 12 starting from 523, and the takeoff emissions from all 18 aircraft are distributed in the grids containing runway 30L. This same method is used for landing and taxiing to the terminal area and for other runways and ramp destinations. Tables 15 through 21 list the times in mode by grid and by mode for the aircraft categories using the remaining runways. A complicating factor is the queuing of aircraft waiting to take off during periods of heavy volume. The EPA report APTD-1470 recommends adding extra idle time due to queuing as T = (N-30)/10 when the landing and takeoff volume exceeds 30 per hour. T is the time queued (minutes) and N is the LTO volume. This relationship is based on data from Chicago's O'Hare airport and assumes the use of two parallel runways. Observation at Lambert Field indicate, however, that no extensive queuing occurs ever during periods of heaviest volume. Emission Rates Most emission rate data for aircraft have been gathered by the Cornell Aeronautical Laboratory. These are compiled in the report "Analysis of Aircraft Exhaust Emission Measurements," (PB-204-879) and summarized in 3 the EPA report "Compilation of Air Pollutant Emission Factors," (AP-42). Emission rates for SCL are not given, possibly because of variation with fuel sulfur content, but they can be estimated by the product of the fuel use rate and the percent of sulfur in the fuel. 35 ------- Table 14. TIMES IN MODE BY GRID BY MODE FOR AIR TRAFFIC USING RUNWAY 30L (seconds) Grid 2187 683 654 653 616 589 588 560 559 524 523 522 493 492 452 451 389 Air carrier Idle 0 0 0 0 0 0 0 20 45 0 540 0 0 520 0 0 0 Taxi 0 0 0 0 0 0 0 0 15 0 130 0 0 230 0 0 0 Take- off 0 0 0 0 0 0 0 10 2 0 30 0 0 0 0 0 0 Land- ing 0 0 0 0 0 0 0 0 0 0 20 0 0 15 0 0 0 Climb- out 35 0 0 0 0 0 0 0 0 0 3 0 15 5 15 0 35 Approach 0 26 26 26 26 26 26 3 7 0 0 0 0 0 0 0 0 Military Idle 0 0 0 -0 0 0 0 0 130 0 150 0 0 200 0 0 0 Taxi 0 0 0 0 0 0 0 0 30 0 120 0 0 150 0 0 0 Take- off 0 0 0 0 0 0 0 10 0 0 14 0 0 0 0 0 0 Land- ing 0 0 0 o 0 0 0 4 0 0 20 0 0 0 0 0 0 Climb - out 10 0 0 0 0 0 0 0 0 0 0 0 8 0 2 0 10 Approach 0 15 15 15 15 15 15 2 4 0 0 0 0 0 0 0 0 ------- Table 15. TIMES IN MODE BY GRID BY MODE FOR AIR TRAFFIC USING RUNWAY 12R (seconds) Grid 2187 683 654 653 616 589 588 560 559 524 523 522 493 492 452 451 389 Air carrier Idle 0 0 0 0 0 0 0 0 0 0 524 0 15 520 45 0 0 Taxi 0 0 0 0 0 0 0 0 0 0 210 0 45 110 15 0 0 Take- off 0 0 0 0 0 0 0 0 0 0 2 0 20 10 10 0 0 Land- ing 0 0 0 0 0 0 0 0 0 0 10 0 5 20 0 0 0 Climb- out 0 13 13 13 13 13 13 4 10 0 15 0 0 0 0 0 0 Approach 68 0 0 0 0 0 0 0 0 0 0 0 5 0 5 0 68 Military Idle 0 0 0 0 0 0 0 0 0 0 0 0 60 420 0 0 0 Taxi 0 0 0 0 0 0 0 0 0 0 40 0 70 50 0 0 0 Take- off 0 0 0 0 0 0 0 0 0 0 8 0 8 8 0 0 0 Land- ing 0 0 0 0 0 0 0 0 0 0 8 0 8 8 0 0 0 Climb- out 0 0 6 0 6 6 0 2 4 0 6 0 0 0 0 0 0 Approach 45 0 0 0 0 0 0 0 0 0 0 0 0 0 6 0 45 ------- Table 16. TIMES IN MODE BY GRID BY MODE FOR AIR TRAFFIC USING RUNWAY 30R (seconds) Air taxi Grid 560 559 524 523 522 493 492 452 451 Idle 150 0 0 0 0 600 0 0 0 Taxi 0 0 80 80 0 320 0 0 0 Take- off 0 0 13 20 0 0 0 0 0 Land- ing 15 0 0 18 0 0 0 0 0 Climb- out 0 0 0 0 0 200 0 25 0 Approach 273 0 0 0 0 0 0 0 0 General aviation Idle 100 0 0 0 0 500 0 0 0 Taxi 0 0 80 80 0 320 0 0 0 Take- off 0 0 8 20 0 0 0 0 0 Land- ing 9 0 0 18 0 0 0 0 0 Climb- out 0 0 0 0 0 250 0 50 0 Approach 360 0 0 0 0 0 0 0 0 OJ 00 Table 17. TIMES IN MODE BY GRID BY MODE FOR AIR TRAFFIC USING RUNWAY 12L (seconds) Air taxi Grid 560 559 524 523 522 493 492 452 451 Idle 0 0 0 0 0 750 0 0 0 Taxi 0 0 90 90 0 300 0 0 0 Take- off 0 0 17 16 0 0 0 0 0 Land- ing 0 0 17 16 0 0 0 0 0 Climb- out 225 0 0 0 0 0 0 0 0 Approach 0 0 0 0 0 123 0 150 0 General aviation Idle 0 0 0 0 0 600 0 0 0 Taxi 0 0 90 90 0 300 0 0 0 Take- off 0 0 10 8 0 0 0 0 0 Land- ing 0 0 9 9 0 0 0 0 0 Climb- out 300 0 0 0 0 0 0 0 0 Approach 0 0 0 0 0 160 0 200 0 ------- Table 18. TIMES IN MODE BY GRID BY MODE FOR AIR TRAFFIC USING RUNWAY 35 (seconds) Air taxi Grid 560 559 524 523 522 493 492 452 451 Idle 0 0 0 250 0 500 0 0 0 Taxi 0 0 160 160 44 300 0 0 0 Take- off 0 0 0 33 0 0 0 0 0 Land- ing 0 0 0 33 0 0 0 0 0 Climb- out 0 0 225 0 0 0 0 0 0 Approach 0 0 0 0 273 0 0 0 0 General aviation Idle 0 0 0 50 0 450 0 0 0 Taxi 0 0 160 160 44 300 0 0 0 Take- off 0 0 0 18 0 0 0 0 0 Land- ing 0 0 0 18 0 0 0 0 0 Climb- out 0 0 300 0 0 0 0 0 0 Approach 0 0 0 0 360 0 0 0 0 Table 19. TIMES IN MODE BY GRID BY MODE FOR AIR TRAFFIC USING RUNWAY 17 (seconds) Air taxi Grid 560 559 524 523 522 493 492 452 451 Idle 0 0 250 0 0 500 0 0 0 Taxi 0 0 100 100 0 380 0 0 0 Take- off 0 0 30 3 0 0 0 0 0 Land- ing 0 0 30 3 0 0 0 0 0 Climb- out 0 0 0 40 185 0 0 0 0 Approach 0 0 273 0 0 0 0 0 0 General aviation Idle 0 0 50 0 0 450 0 0 0 Taxi 0 0 100 100 0 380 0 0 0 Take- off 0 0 15 0 0 0 0 0 0 Land- ing 0 0 15 0 0 0 0 0 0 Climb- out 0 0 0 50 250 0 0 0 0 Approach 0 0 360 0 0 0 0 0 0 ------- Table 20. TIMES IN MODE BY GRID BY MODE FOR AIR TRAFFIC USING RUNWAY 6 (seconds) Air taxi Grid 560 559 524 523 522 493 492 452 451 Idle 0 0 0 0 0 300 0 300 150 Taxi 0 0 0 0 0 290 10 10 10 Take- off 0 0 0 0 0 13 10 0 10 .Land- ing 0 0 0 0 0 11 11 0 11 Climb- out 0 0 125 0 0 100 0 0 0 Approach 0 0 0 0 0 0 0 0 273 General aviation Idle 0 0 0 0 0 250 0 250 100 Taxi 0 0 0' 0 0 290 10 10 10 Take- off 0 0 0 0 0 8 5 0 5 - Land- ing 0 0 0 0 0 6 6 0 6 Climb- out 0 0 175 0 0 125 0 0 0 Approach 0 0 0 0 0 0 0 0 360 Military Idle 0 0 0 0 0 0 400 0 80 Taxi 0 0 50 0 0 0 200 0 50 Take- off 0 0 0 0 0 20 2 0 2 Land- ing 0 0 0 0 0 20 2 0 2 Climb- out 0 0 25 0 0 5 0 0 0 Approach 0 0 0 0 0 0 0 0 96 Table 21. TIMES IN MODE BY GRID BY MODE FOR AIR TRAFFIC USING RUNWAY 24 (seconds) Air taxi Grid 560 559 524 523 522 493 492 452 451 Idle 0 0 150 0 0 300 0 0 300 Taxi 0 0 150 0 0 230 0 0 0 Take- off 0 0 23 0 0 10 0 0 0 Land- ing 0 0 23 0 0 10 0 0 0 Climb- out 0 0 0 0 0 40 0 0 185 Approach 0 0 273 0 0 0 0 0 0 General aviation Idle 0 0 100 0 0 250 0 0 250 1 Taxi 0 0 150 0 0 230 0 0 0 Take- off 0 0 12 0 0 6 0 0 0 Land- ing 0 0 12 0 0 6 0 0 0 Climb- out 0 0 0 0 0 40 0 0 260 Approach 0 0 360 0 0 0 0 0 0 Military Idle 0 0 80 0 0 0 400 0 0 Taxi 0 0 120 100 0 0 100 0 0 Take- off 0 0 24 0 0 0 0 0 0 Land- ing 0 0 24 0 0 0 0 0 0 Climb- out 0 0 0 0 0 5 0 0 25 Approach 0 0 96 0 0 0 0 0 0 ------- Table 22 lists the air carrier aircraft and engines used at Lambert Field as compiled from the Official Airline Guide. The numbers of each type of engine were used to weight the emission factors for each to prepare a single, composite set of weighted emission factors for air carriers. The emission factors for each engine type and the weighted factors are presented in Table 23. Table 22. AIRCRAFT AND ENGINE VOLUMES FOR LAMBERT FIELD, ST. LOUIS Aircraft DC 9 727 707 CVS 320 880 DC 10 737 BAClll TOTAL Engine type Number 110 76 24 25 2 2 3 5 ' 5 252 JT3D 96 96 JT4A 8 , 8 JT8D 220 228 10 458 CJ805 8 8 JT9D 9 9 T56-A7 50 50 RRMK511 10 10 Composite emission factors were also prepared for the other three air- craft categories. For air taxi the weighting factors are 100 T56-A7 engines and 20 RRMK511 engines. General aviation was given an equal distribution of 0-320, 0-360, and 0-200 engines. Military aircraft were half J79 and half J57 engines. The composite emission factors by pol- lutant and by mode are listed in Table 24. The S09 emission factors presented in this report are for an assumed 0.05 percent sulfur content fuel.3 41 ------- Table 23. EMISSION FACTORS BY ENGINE TYPE AND MODE FOR AIR CARRIERS (kg/hr) Mode Idle Taxi Takeoff Landing Climbout Approach Pollutant CO HC NOx S02 Particulate CO HC NOX S02 Particulate CO UP NO* S02 Particulate CO HC NOX S02 Particulate CO HC ' NCx S02 Particulate CO HC NOx S02 Particulate JT3D 49.4 44.7 0.649 0.396 0.20 49.4 44.7 0.649 0.396 0.2 5.6 Oil 67.1 4.915 3.7 33.9 27.9 18.1 0.662 1.6 6.94 2.23 43.6 4.062 3.9 18.0 3.56 9.89 1.877 3.6 JT4A 28.5 29.4 1.23 0.631 0.54 28.5 29.4 1.23 0.631 0.54 8.53 0 ^06 107.0 7.051 95 21.1 18.0 29.0 0.545 3.0 8.30 0.576 70.3 5.939 9.1 11.9 1.74 16.3 2.724 2.7 JT8D 15.2 3.71 1.32 0.435 0.16 15.2 3.7 1.32 0.435 0.16 3.40 n ^^^ 89.8 3.971 1.7 11.3 2.4 24.6 0.248 0.61 4.03 0.418 59.4 3.328 1.2 8.26 0.794 14.0 1.546 0.68 CJ805 28.9 12.4 0.712 0.454 0.59 28.9 12.4 0.712 0.454 0.59 13.2 A O crO 50.3 4.518 6.8 23.6 7.7 13.8 0.275 2.4 13.1 0.264 33.6 3.760 6.8 19.4 1.10 8.07 1.713 2.3 JT9D 46.3 12.4 2.75 0.788 1.0 46.3 12.4 2.75 0.788 1.0 3.76 1 *}A. 327 7.735 1.7 31.1 8.0 84.1 0.379 1.2 5.31 1.20 208 6.494 1.8 14.8 1.36 24.5 2.361 1.0 T56-A7 6.94 2.93 0.98 0.249 0.73 6.94 2.93 0.98 0.249 0.73 0.975 n i QS 10.40 1.943 1.7 4.66 1.84 3.649 0.076 1.07 1.37 0.216 9.62 0.865 1.4 1.66 0.235 3.53 ' 0.478 1.4 RRMK511 27.3 30.0 0.385 0.300 0.077 27.3 30.0 0.385 0.300 0.077 6.44 69.4 3.459 7.3 20.76 18.31 19.10 0.222 1.91 6.94 0.110 52.2 2.883 4.5 17.7 1.91 13.8 1.384 0.68 Weighted factors 20.66 10.77 1.19 0.42 0.23 20.66 10.77 1.19 0.42 0.23 3.78 n £-1 82,92 3.97 2.25 14.88 6.78 22.66 0.30 0.88 4.49 0.68 54.13 3.32 1.85 9.63 1.21 12.66 1.54 1.23 -p- N> ------- Table 24. COMPOSITE EMISSION FACTORS FOR AIR TAXI, GENERAL AVIATION, AND MILITARY AIRCRAFT AT LAMBERT FIELD (kg/hr) Mode Idle Taxi Takeoff Landing Climbout Approach Pollutant HC CO Ncx S02 Particulate HC CO NOX S02 Particulate HC CO N0x S02 Particulate HC CO N0x S02 Particulate HC CO NOX so2 Particulate HC CO NO* S02 Particulate Air taxi 7.442 10.333 0.881 0.258 0.621 7.442 10.333 0.881 0.258 0.621 0.195 1.886 20.233 2.196 2.633 4.585 7.343 6.224 0.100 1.210 0.198 2.298 16.717 1.201 1.917 0.514 4.333 5.242 0.629 1.280 General aviation 0.428 4.779 0.006 0.005 0.0 0.428 4.779 0.006 0.005 0.0 0.642 32.923 0.143 0.031 0.0 0.451 12.764 0.044 0.012 0.0 0.488 28.393 0.157 0.027 0.0 0.249 12.471 0.037 0.012 0.0 Military 24.0 36.0 1.5 0.509 10.0 24.0 36.0 1.5 0.509 10.0 3.5 224.0 56.0 8.916 73.5 24.0 36.0 1.5 0.509 10.0 1.5 6.0 42.5 3.898 48.0 1.5 7.5 30.5 3.548 54.5 43 ------- GROUND SERVICE VEHICLE OPERATIONS The activity of ground service vehicles and the vehicles used depend on the type of aircraft being serviced. For Lambert Field, a composite time for servicing was computed for each of the various types of ve- hicles for the air carrier equipment mix. Table 25 presents a summary of ground service vehicle usage and times for the different types of aircraft.^ The composite service time was computed using the aircraft volumes that were also used to compute composite emission factors. Table 26 lists the fuel consumption rates, while Table 27 gives the o emission factors for each. Emission factors for S0« can be computed from Table 27 and the sulfur content of the fuel. The hourly emissions from ground service vehicles are found by multiplying the times in Table 25, the consumption rates in Table 26, and the emission factors in Table 27 by half the hourly volume computed for aircraft activity. FUEL HANDLING AND STORAGE The Allied Aviation Fueling Company of St. Louis, Inc., is the major supplier of fuel at Lambert. The fuel is stored on a hill outside the airport boundary and is piped underground to the ramp area of the air- line terminal. The majority of aircraft fueling is done directly from outlets on the ramp, although fueling trucks are used at a few locations. The fuel storage tanks are equipped with vapor recovery systems and the cartridges are serviced regularly. Any fuel spillage during fueling is promptly washed away. Approximately 12 million gallons of fuel are pumped per month £ The working loss of hydrocarbons varies with temperature, and Table 28 lists the 94 year average high, medium, and low temperatures for each month as compiled in the Climatic Atlas of the U. S. The average low 44 ------- Table 25. SERVICE TIMES OF AIRCRAFT GROUND SERVICE VEHICLES ^~~"\^^ Aircraft Vehicle ^"^-^^^ 1. Tractor 2. Belt Loader 3. Container Loader 4. Cabin Service 5. Lavatory Truck 6. Water Truck 7. Food Truck 8. Fuel Truck 9. Tow Tractor 10. Conditioner 11. Airstart Transporting Engine Diesel Power Unit Time in vehicle-minutes DC- 10 148 40 80 25 18 10 20 45 10 0 0 0 B-707 66 37 12 12 15 0 20 37 10 30 10 8 B-727 66 28 6 12 15 0 17 20 10 0 0 0 DC- 9 48 15 0 0 15 10 17 15 5 0 0 0 B-737 85 30 0 15 15 0 20 15 5 0 0 0 C-880 40 40 0 0 20 0 20 20 15 0 15 11 F-227 55 0 0 0 10 10 10 10 5 0 0 0 C-580 50 25 0 0 10 10 10 20 5 0 0 0 Composite times 56 23 3 5 15 5 17 19 8 3 2 2 -p- Ul ------- Table 25 (continued). SERVICE TIMES OF AIRCRAFT GROUND SERVICE VEHICLES "-^^^ Aircraft ~^^^ Vehicle "^-^^^ 12. Ground Power Unit Transporting Engine Gasoline Power Unit Diesel Power Unit 13. Transporter 14. Auxiliary Power Unit Time in vehicle-minutes DC- 10 0 0 0 0 Yes B-707 9 4 4 10 No B-727 0 0 0 3 Yes DC- 9 0 0 0 0 Yes B-737 0 0 Q 0 Yes C-880 35 15 15 0 No F-227 - 0 0 0 0 No C-580 0 0 0 0 No Composite times 4 2 2 2 30 ------- Table 26. GROUND SERVICE VEHICLE FUEL CONSUMPTION RATES Vehicle Rate of fuel consumption (gal/hr) 1. Tractor 2. Belt Loader 3. Container Loader 4. Cabin Service 5. Lavatory Truck 6. Water Truck 7. Food Truck 8. Fuel Truck 9. Tow Tractor 10. Conditioner 11. Airstart Transporting Engine Diesel Power Unit 12. Ground Power Unit Transporting Engine Gasoline Power Unit Diesel Power Unit 13. Transporter 14. Auxiliary Power Unit 1.80 0.70 1.75 1.50* 1.50£ 1.50< 2.00 1.70* 2.35 1.75£ 1.40 8.20 2.00 5.00 7.10 1.50 7.10 a Estimated values 47 ------- Table 27. GROUND SERVICE VEHICLE EMISSION FACTORS Vehicle Gasoline Engines Diesel Engines Pollutant emissions (grams/gal) CO 999.0 147.6 BC 223.2 29.5 NOX 57.0 154.4 Particulates 1.8 11.4 Table 28. NINETY-FOUR YEAR AVERAGE HIGH, MEDIUM, AND LOW TEMPERATURES FOR ST. LOUIS Month January February March April May June July August September October November December High 40 44 53 66 75 85 89 87 81 70 59 43 Medium 32 35 43 55 64 74 78 77 70 59 49 35 Low 23 25 32 44 53 63 67 66 58 47 35 27 48 ------- temperature is used for the 8 p.m. to 8 a.m. period, the average medium is used for 8 a.m. to 1 p.ra. and 3 p.m. to 8 p.m., and the average high is used for 1 p.m. to 3 p.m. The hydrocarbon emission factors are calculated by using the method from the American Petroleum Institute publication API 2513.8 Table 29 lists the working loss factors computed for each month for each time period. The gallons of fuel pumped.in any hour are computed by the same method used for aircraft volumes. Hence, where G is gallons/month (12 million) and the factor of 1/2 assumes an m even distribution of landings and takeoffs. The mass emissions are then calculated by multiplying G, by the emission factor appropriate to the hour of the day (Table 29), and then multiplying the result by the volume to mass factor of 2.8 kg/gal. These emissions are restricted to grids 492 (one third) and 523 (two thirds). ENGINE TESTING AND MAINTENANCE Engine testing and maintenance is done by McDonnell Douglas in associa- tion with their manufacturing facilities at Lambert. The details of their testing and maintenance are classified, since their production consists of military aircraft. Their production rate is "about" two aircraft per day, and hence this emission source will be excluded from the inventory 49 ------- Table 29. WORKING LOSS FACTORS FOR THE THREE TIME PERIODS FOR EACH MONTH Month January February March April May June July August September October November December Working loss (gallons/1000 gallons throughput) 0800-1300 1500-2000 0.87 0.94 1.12 1.42 1.61 2.10 2.17 2.16 1.92 1.52 1.17 0.94 1300-1500 1.03 1.17 1.38 1.65 2.11 2.58 2.76 2.64 2.37 1.92 1.41 1.12 2000-0800 0.71 0.72 0.87 1.17 1.38 1.60 1.81 1.80 1.51 1.20 0.94 0.78 50 ------- SECTION VI SCOTT AIR FORCE BASE Scott Air Force Base is an Air Medical and Airlift Wing of the Military Airlift Command. The air traffic is light; it averages approximately 40 flights per day. AIRCRAFT FLIGHT ACTIVITY 9 The five months of data available from Scott were not sufficient to determine the percent of traffic by month. Therefore, a monthly mean and standard deviation was calculated from the five months of data. This is used with the day of week and hour of the day percentages to find the hourly traffic. Since the flights are predominantly by military aircraft, the categories of jet and piston aircraft are used. Table 30 lists the monthly volumes and the five month means and stan- dard deviations for the two categories. Table 30. FIVE-MONTH AIR TRAFFIC VOLUMES, MEANS, AND STANDARD DEVIATIONS AT SCOTT AFB, 1973 - 1974 Month Sept. Oct. Nov. Dec. Jan. Mean Standard Deviation Jet 1208 1088 788 461 617 832 313 Piston 451 470 400 281 285 379 87 Total 1659 1558 1188 742 912 1212 397 51 ------- Percentages by the day of the week are given in Table 31. Percentages by the hour of the day were obtained from percentages for 6-hour periods beginning at 0400. Thus, all hours within a 6-hour block are given the same percent of total daily traffic. These are shown in Table 32. Table 31. PERCENT OF AIR TRAFFIC BY DAY OF WEEK AT SCOTT AFB Day . Sunday Monday Tuesday Wednesday Thursday Friday Saturday Jet 13.61 13.86 12.29 15.16 14.58 15.75 14.75 Piston 15.97 13.86 12.50 12.08 15.93 14.11 15.54 Scott Field lies in four grid elements as shown in Figure 5. There are only two runways at Scott, runways 13 and 31 (Figure 5). Hence the grid elements used for the different modes are easily defined, and these are implicit in Tables 33 and 34 which give the time in the various modes for each grid by runway and type of aircraft. EMISSION FACTORS Jet flights at Scott AFB are predominantly by C-9 and C-141 aircraft.^ The C-9 has two JT8D engines, while the C-141 has four TF-33 engines.10 The ratio of activity of the C-9 to C-141 is about 3.75 to 1.0, so the weighting by engine type is about 1.87 (JT8D) to 1.0 (TF-33). Composite emission factors based on these engines were calculated, and these are given in Table 35. 52 ------- Table 32. PERCENT OF AIR TRAFFIC BY HOUR AT SCOTT Ai'B. Hour 0000-0100 0100-0200 0200-0300 0300-0400 0400-0500 0500-0600 0600-0700 0700-0800 0800-0900 0900-1000 1000-1100 1100-1200 1200-1300 1300-1400 1400-1500 1500-1600 1600-1700 1700-1800 1800-1900 1900-2000 2000-2100 2100-2200 2200-2300 2300-2400 Jet 5,367 5.367 5.367 5.367 0.841 0.841 0.841 0.841 0.841 0.841 4.054 4.054 4.054 4.054 4.054 4.054 6.404 6.404 6.404 6.404 6.404 6.404 5.367 5.367 Piston 5.226 5.226 5.226 5.226 0.298 0.298 0.298 0.298 0.298 0.298 3.799 3.799 3.799 3.799 3.799 3.799 7.344 7.344 7.344 7.344 7.344 7.344 5.226 5.226 53 ------- Figure 5. Runway layout and grid element overlay for Scott AFB 54 ------- Table 33. TIME IN MODE BY GRID AND MODE FOR AIR- CRAFT USING RUNWAY 13, SCOTT AFB (seconds) Mode Idle Taxi Takeoff Landing Climbout Approach 2388 Jet 0 0 0 0 0 110 Piston 0 0 0 0 0 100 1637 Jet 20 40 0 0 108 0 Piston 0 50 0 0 300 0 1621 Jet 40 50 20 15 0 56 Piston 80 50 16 16 0 176 1620 Jet 420 510 22 20 0 0 Piston 720 600 20 20 0 0 Table 34. TIME IN MODE BY GRID AND MODE FOR AIR- CRAFT USING RUM-JAY 31, SCOTT AFB (seconds) Mode Idle Taxi Takeoff Landing Climbout Approach 2388 Jet 0 0 0 0 70 0 Piston 0 0 0 0 200 0 1637 Jet 40 20 10 5 0 166 Piston 80 50 16 10 0 276 1621 Jet 20 20 0 0 30 0 Piston 0 50 20 26 100 0 1620 Jet 420 800 32 30 8 0 Piston 720 700 0 0 0 0 55 ------- Table 35. EMISSION FACTORS FOR SCOTT AFB (kg/hr) Mode Idle Taxi Takeoff Landing Climb out Approach Pollutant CO HC NOX SO 2 Particulate CO HC NOX S02 Particulate CO HC NOX S02 Particulate CO HC NOX S02 Particulate CO HC NOX S02 Particulate CO HC NOX S02 Particulate Jet 31.70 22.51 1.17 0.470 1.60 31.70 22.51 1.17 0.470 1.60 3.18 0.60 77.09 3.949 20.16 21.56 15.38 21.29 0.695 7.26 4.07 0.71 50.91 3.388 18.19 10.95 10.96 12.96 1.600 9.15 . Piston 59.00 10.30 0.08 0.07 NA 64.50 13.20 0.06 0.07 NA 417.70 9.23 2.15 0.40. NA 160.62 8.96 0.67 0.16^ NA 305.80 5.43 1.85 0.30< NA 156.10 3.50 0.64 0.15: NA 56 ------- Piston aircraft flights are largely by T-29, C-118, and C-131 aircraft, all of which use Pratt Whitney R-2800 engines. Emission factors for piston aircraft flights are also listed in Table 35. GROUND SERVICE VEHICLE OPERATIONS There are eight petroleum, oil, and lubricants trucks, or POL trucks used to service aircraft at Scott Field. These run an average of 3 hours 25 minutes each per grid element number 1620. 9 hours 25 minutes each per .day, or a total of 27 hours 20 minutes in In addition to the POL trucks, the fleet service vehicles listed in Table 36 are used. Their combined use accounts for approximately 15 9 gallons of fuel per day. Emission factors for these vehicles are given in the previous Table 27. The hourly emissions are computed by distributing the daily emissions according to the average hourly per- cent of daily activity for piston and jet aircraft. Table 36. GROUND SERVICE VEHICLES USED AT SCOTT AFB Service vehicle Fork lift Water truck Multi-stop High lift Lavatory truck Warehouse tug Step van Number 2 1 2 1 2 2 2 Emissions from the POL trucks are found using the fuel consumption rate for fuel trucks given in Table 26 (1.70 gallons/hour) and the emission factors from Table 27. These total emissions are also 57 ------- distributed by the hourly percent of daily activity to find the emissions for a particular hour. FUEL HANDLING AND STORAGE The volume of fuel stored at Scott: AFB is classified. The average use is 724,000 gallons of jet fuel and 82,000 gallons of avgas per month. Hourly volumes of fuel pumped can be calculated using the day of week and hour of day percentages used to find activity. The emissions are then calculated using the factors given in Table 29 for jet fuel and a factor of 5 kg/1000 gallons pumped for avgas. ENGINE TESTING AND MAINTENANCE Engine testing and maintenance activity does not follow a prescribed schedule and hence cannot be accurately accounted for on an hourly basis. Emissions could be computed as an average value for each hour, but the number of engine runups is so small (about 14 per week) that the emissions would be lost on an hourly basis. 58 ------- SECTION VII CIVILIAN AIRPORTS INTRODUCTION Civilian airports can be divided into those with control towers and those without. This division also applies to the degree of data availability, and to the volume and type of traffic. Two civilian airports in the St. Louis AQCR, Spirit of St. Louis and Civic Memorial, have control towers; the remainder do not. FLIGHT ACTIVITY More extensive data are available for Civic Memorial Airport from the FAA control tower. These data have been reduced in the same manner as those for Lambert Field. Table 37 gives the monthly percentages of annual traf- fic, Table 38 gives the percentages by the day of the week, and the per- centages by the hour of the day are listed in Table 39. These data are used to compute hourly traffic by the same method described for Lambert Field. Uncontrolled airports do not record air traffic volumes. However, FAA Forms 5010-1 list estimated annual volumes which can be used with the dis- tribution of traffic found at Civic Memorial. Table 40 presents the annual volumes from FAA Forms 5010-1. Two exceptions are Civic Memorial and Spirit of St. Louis for which the volumes were obtained from control tower records. 59 ------- Table 37. PERCENT OF AIR TRAFFIC BY MONTH AT CIVIC MEMORIAL AIRPORT Month January February March April May June July August September October November December Monthly percent 7.86 7.95 6.98 9.26 9.48 8.88 8.44 9.90 7.78 9.48 8.49 5.50 Table 38. PERCENT OF AIR TRAFFIC BY DAY OF WEEK AT CIVIC MEMORIAL AIRPORT Day Sunday Monday Tuesday Wednesday Thursday Friday Saturday Day percent 17,47 11.14 12.54 13.30 12.76 14.10 18.69 ------- Table 39. PERCENT OF AIR TRAFFIC BY HOUR OF THE DAY AT CIVIC MEMORIAL AIRPORT Hour 0700 - 0800 - 0900 - 1000 - 1100 - 1200 - 1300 - 1400 - 1500 - 1600 - 1700 - 1800 - 1900 - 2000 - 2100 - 2200 - 0800 0900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100 2200 2300 Hourly percent 1.15 4.63 7.20 7.08 8.82 9.51 10.51 10.83 12.45 12.91 6.17 3.19 2.23 2.40 0.56 0.34 Table 40. ANNUAL AIR TRAFFIC VOLUMES AT CIVILIAN AIRPORTS IN THE ST. LOUIS AQCR Airport St. Clair Wentzville Arrowhead Creve Coeur St. Charles St. Charles Smartt Weiss Festus Gelhardt Sparta Highland Greenville Bi-State Parks Civic Memorial Spirit of St. Louis Annual volume 14,400 27,000 60,500 63,100 63,000 27,000 130,000 15,000 14,183 8,012 28,000 38,734 192,030 156,607 114,426 ------- SPATIAL DETAIL Five of the general aviation airports lie in more than one grid element. These are Civic Memorial, Spirit of St. Louis, Bi-State Parks, St. Clair, and Creve Coeur Airports, The remaining ten are contained in one grid. Figures 6 through 10 show the layout of the multi-grid airports. The grids and the key operating modes for each grid for each active runway are listed in Tables 41 through 45. The airports which lie in only one grid element are listed, along with the grid numbers and sizes, in Table 46. Figures 11 through 20 depict the layout of these remaining airports. EMISSIONS FROM FLIGHT ACTIVITY The emission factors for the civilian airports are those for general avia- tion listed in Table 24 for a mix of general aviation aircraft types. The average times in mode are given in Table 47. When an airport lies in more than one grid, the time for each mode is distributed equally among the grids identified for the mode (Tables 41 through 45). The emissions are computed by the same multiplication of volume, emission factors, and times in mode as described for Lambert Field. GROUND SERVICE VEHICLES Ground service vehicles at civilian airports are limited to fueling trucks, and even these are absent at all but the large civilian airports. Most of these airports provide fueling as at a gas station; airplanes are taxied to the gas pump for filling. The fueling truck operation is erratic, depending on the amount of traffic, and it is not possible to pin down the actual operating characteristics. 62 ------- N 1401 SCALE IN FEET Figure 6. Diagram of Civic Memorial Airport shov . grid element overlay 63 ------- Table 41. OPERATING MODES FOR EACH GRID BY ACTIVE RUNWAY AT CIVIC MEMORIAL AIRPORT -P- Runway 11 29 17 35 Grid 1402 1403 1424 1444 1402 1403 1424 1444 1401 1402 1403 1401 1402 1403 X-coord 4308 4309 4308 4309 4307 Y-coord 755 755 756 757 755 - Size 1 1 1 2 1 Idle Taxi X X X X X X X X X Takeoff X X X X X X X X X X X X X X Climb out Approach Landing x' X X X X X X X X X X X X X Taxi X X X X X X X X X ------- 0 500 1000 2000 1 i j i SCALE IN FEET Figure 7. Diagram of Spirit of St. Louis Airport showing grid element overlay 65 ------- Table 42. OPERATING MODES FOR EACH GRID BY ACTIVE RUNWAY AT SPIRIT OF ST. LOUIS AIRPORT CT\ Runway 8 26 Grid 135 160 135 160 X-coord 4230 4280 Y-coord 700 705 Size 5 5 Idle Taxi X X X X Takeoff X X X X C 1 irab out Approach Landing X X X ! x Taxi X X X X ------- 2286 2289 Figure 8. Diagram of Bi-State Parks Airport showing grid element overlay ------- Table 43. KEY OPERATING MODES FOR EACH GRID FOR EACH RUNWAY AT BI-STATE PARKS AIRPORT Runway 4 22 12 30 Grid 2286 2293 2289 2286 2293 2286 2292 2293 2297 2292 2293 2297 Size 2 1 1 2 1 2 1 1 1 1 1 1 Idle X X X X X Taxi X X X X X X Takeoff X X X X X X X X X X X Landing X X X X X X X X X X X Taxi X X X X X 68 ------- 0 200400' 1000 I I I . . I SCALE IN FEET Figure 9. Diagram of St. Clair Airport showing grid element overlay 69 ------- Table 44. KEY OPERATING MODES FOR EACH GRID FOR EACH RUNWAY AT ST. GLAIR AIRPORT Runway 2 20 Grid 2021 2024 2021 2024 Size 2 3 2 3 Idle X X Taxi X X X X Takeoff X X Landing X X Taxi X X X X 70 ------- 0 500 1000 1500 ( I I | SCALE IN FEET Figure 10. Diagram of Creve Coeur Airport showing grid element overlay 71 ------- Table 45. KEY OPERATING MODES FOR EACH GRID FOR EACH RUNWAY AT CREVE COEUR AIRPORT Runway 16 34 7 25 Grid 2103 2104 2103 2104 2103 2104 2125 2103 2104 2105 Size 2 2 2 2 2 2 2 2 2 2 Idle X X X X Taxi X X X X X X X X Takeoff X X X X X X X X Landing X X X X X X X X Taxi X X X X X X X X 72 ------- 1200 Figure 11, Diagram of Sparta Airport - grid element 1633 73 ------- Table 46. GENERAL AVIATION AIRPORTS CONTAINED IN ONE GRID, ST. LOUIS AQCR Airport Wentzville Arrowhead St. Charles St. Charles Smartt Weiss x Festus Gebhardt Sparta Highland Greenville Grid number 76 2102 241 242 2161 467 883 1633 1709 1815 Grid size (km) 10.0 2.0 5.0 10.0 4.0 2.0 2.0 10.0 10.0 10.0 74 ------- 0 SQQ 1000 i i I SCALE IN FEET 36 N Figure 12. Diagram of Wentzville Airport - grid element 76 ------- 500 1000 SCALE IN FEET Figure 13. Diagram of Arrowhead Airport - grid element 2102 76 ------- 0 200 600 1000 i i i i i i SCALE IN FEET Figure 14. Diagram of St. Charles Airport - grid element 241 77 ------- f- + -t -f- ft r SCALE IN FEET Figure 15. Diagram of Weiss Airport - grid element 2161 78 ------- SCALE IN FEET Figure 16. Diagram of Festus Airport - grid element 467 79 ------- N n <* fr ru w 0 500 ]000 ]500 I i i | SCALE IN FEET Figure 17. Diagram of St. Charles Smartt Airport - grid element 242 ------- N 1000 SCALE IN FEET Figure 18. Diagram of Highland Airport - grid element 1709 81 ------- N 0 600 1200 1 i i SCALE IN FEET Figure 19. Diagram of Gebhardt Airport - grid element 883 82 ------- N 0 600 SCALE IN FEET L 81 36 Figure 20. Diagram of Greenville Airport - grid element 1815 83 ------- Table 47. TIMES IN MODE FOR GENERAL AVIATION AIRCRAFT AT CIVILIAN AIRPORTS Mode Idle Taxi Takeoff Landing Climbout Approach Time (minutes) 8.0 8.0 0.3 0.3 4.98 6.00 Table 48. ANNUAL VOLUMES OF FUEL SALES AT THE GENERAL AVIATION AIRPORTS Airport Annual fuel sales (1000 gallons) Sparta Greenville Gebhardt Highland Bi-State Parks Civic Memorial Festus Weiss Creve Coeur St. Charles St. Charles Smartt St. Glair Arrowhead Wentzville Spirit of St. Louis 36 15 15 26 350 350 42 48 26 48 20 48 48 15 200 84 ------- The emissions from one or two fueling trucks are negligible compared to * emissions from automobile traffic, and hence ground service vehicle emis- sions (where they exist) will be excluded from the methodology for civil- ian airports. FUEL STORAGE AND HANDLING Fuel storage and handling losses are calculated as at Lambert and Scott. The working loss factor is 5 kg/1000 gallons. The general aviation air- ports were surveyed to determine their fuel sales. Table 48 shows the annual gallons of fuel pumped at each airport. These annual figures are converted to hourly volumes by applying the aircraft volume distributions of Tables 37, 38, and 39 as described previously for Lambert Field. ENGINE TESTING AND MAINTENANCE Engine testing and maintenance at the small airports is limited and some- times non-existent. Predicting the occurrence or frequency of this emis- sion source with any accuracy is unreasonable on an hourly basis. Because of this, and because this source is such a small contributor to emissions at these airports, emissions from engine testing and maintenance will not be considered. 85 ------- SECTION VIII METHODOLOGY SUMMARY This section presents a "s'tep-by-step" methodology for computing emis- sions at the airports in the St. Louis AQCR. It is based on the results of data collection from the individual airports. It is also based on an assessment of the amount of detail which can be extracted from available data and on the extent to which additional data can be reasonably and reliably collected in the field. The basic method by which emissions are estimated is to construct matrices and vectors of the applicable data and then to add and multiply these matrices and vectors so that the result is hourly emissions for each of the grid elements involved. LAMBERT FIELD Emissions From Aircraft Flight Operations Step 1. Identify the month, day of the week, and hour of the day for which emissions are to be estimated. Step 2. Determine the active runway from the wind direction and/or aircraft category. Step 3. For the time identified (Step 1), determine the activity factors for the different aircraft types; M. = percent of annual volume occurring during the month (aircraft category i), D. = percent of monthly'volume occurring on the given day of the week (aircraft category i), 86 ------- H. = percent of daily volume occurring during the hour of interest (aircraft category i). Step 4. For the active runway determined in Step 2, locate the k grid elements through which aircraft pass. Step 5. Determine the percent of activity due to takeoffs and the percent due to landings for the different aircraft types for the hour: to. = percent taking off (aircraft category i), 1. = percent landing (aircraft category i). Step 6. Compute the takeoff and landing volumes for the hour for each category as follows; A'M.-D.'Hn.'tOn. VTO. = - (ODM)(108) where: VTO. = number of takeoffs for aircraft category i A = annual air traffic volume OD = average occurrence of the day of the week during the month = 4.43 for 31-day months = 4.29 for 30-day months = 4.00 for February (4.14 in a leap year) 10 = factor to convert percentages to decimals. Likewise, A-M.-D.-H.'l. \TL - 1111 1 (ODM)(108) Step 7. For the different aircraft categories, activity volumes, and grid elements identified above, determine the j engine operating modes for each grid element. 87 ------- Step 8. Determine the time -in -mode for each aircraft category for each mode in each grid. T.., = time-in-mode j for aircraft category i in grid k. J1K Step 9. Identify the emission rates of the 1 pollutants, EF-i ., of the different aircraft categories for the various engine operating modes. Step 10. Estimate hourly emissions for aircraft category i for each pollutant and grid element as follows; EAFO.kl = (VTO. - EF±1J - TJlk) + (VL. - E Step 11. Compute hourly emissions from all aircraft in each grid element by repeating Step 10 for all categories : EAFO. , = Z E kl ikl Emissions From Ground Service Vehicles Step 12. Identify ground service vehicle requirements for each aircraft type in each grid. CSV. , = ground service vehicle of type m which is required by aircraft type i in grid k. Step 13. Determine service times for each vehicle for each aircraft. ST.' = service time of ground support vehicle type m for aircraft type i. Step 14. Determine fuel consumption rates for the different ground service vehicles. FC = fuel consumption rate for ground service vehicle type m. Step 15. For each type of ground service vehicle, identify the emission rate as a function of fuel consump- tion. 88 ------- ER = emission rate of ground service vehicle m type m of pollutant 1. Step 16. Locate the k grid elements in which ground service vehicles operate. Step 17. Compute hourly emissions in each grid from activity of ground service vehicle type m servicing aircraft type i. EGSV. , , = TT V. ' CSV. , ST. FC ' ER , , imkl 2 i imk im m ml where: EGSV., = emissions of pollutant 1 from ground ser- vice vehicle type m in grid k, and V. = hourly volume of aircraft type i = VTOi + VL± . Step 18. Compute the total ground service vehicle emissions by grid by pollutant summing over all types of aircraft and ground service vehicles: EGSV. . = Z S EGSV. , , . kl . imkl i m Emissions From Fuel Storage and Handling Step 19. Locate grid elements in which fuel is stored or handled. Step 20. Identify types of fuel and volumes stored. Step 21. Determine the mean daily high, low, and medium tempera- ture for the month of interest. Step 22. Determine the working loss factors for each of the three temperatures. ^ Step 23. Determine the daily volume of fuel pumped. Step 24. Distribute the daily volume over 24 hours according to the diurnal flight activity pattern. 89 ------- Step 25. Compute working losses for the hour of interest according to the volume of fuel pumped and the temperature applicable to the time of day as: EFSH, , = emissions of pollutant 1 in grid k due to fuel storage and handling. Emissions From Engine Testing and Maintenance The data required to compute these emissions are classified. However, they are judged to be negligible and are neglected. SCOTT AIR FORCE BASE Emissions From Aircraft Flight Operations Step 26. Identify the day of the week and the hour of the day for which emissions are to be estimated. Step 27. Determine the active runway from the wind direction and/or aircraft category. Step 28. For the time identified (Step 26), determine the activity factors for the different aircraft categories (jet and piston): D. = percent of monthly volume occurring on the given day of the week (aircraft i), H. = percent of daily volume occurring during the hour of interest (aircraft category i). Step 29. For the active runway determined in Step 27, locate the k grid elements through which aircraft pass. Step 30. Compute the total takeoff and landing volumes during the hour as follows (assume 1/2 landing and 1/2 take- off): M'D.-H. V. = i- X (ODM) (104) 90 ------- where: M = mean monthly air traffic volume. Step 31. For the different aircraft categories, activity volumes, and grid elements identified above, determine the j engine operating modes for each grid element. Step 32. Determine the time-in-mode for each aircraft category for each mode in each grid. T.., = time-in-mode j for aircraft category i in grid k. jik Step 33. Identify the emission rates of the 1 pollutants, E^ili» °f the different aircraft categories for the various engine operating modes. Step 34. Estimate hourly emissions for aircraft type i for each grid element as: EAFO., . = V. EF., . T... ikl i ilj jik Step 35. Compute hourly emissions from all aircraft in each grid element by repeating Step 34 for all categories: EAFOkl = Emissions From Ground Service Vehicles Step 36. Identify ground service vehicle requirements for each aircraft type in each grid. CSV. , = ground service vehicle of type m which is required by aircraft type i in grid k. Step 37. Determine service times for each vehicle for each aircraft. ST. = service time of ground support vehicle type m for aircraft type i. 91 ------- Step 38. Determine fuel consumption rates for the different ground service vehicles. FC = fuel consumption rate for ground service vehicle type m. Step 39. For each type of ground service vehicle, identify the emission rate as a function of fuel consump- tion. ER 1 = emission rate of ground service vehicle type m of pollutant 1. Step 40. Locate the k grid elements in which ground service vehicles operates. Step 41. Compute hourly emissions in each grid from activity of ground service vehicle type m servicing aircraft type i. EGSV. .. = 1/2 V. CSV. . 'ST. FC ER . , imkl __ i imk im m ml where: EGSV., = emissions of pollutant 1 from ground ser- vice vehicle type m in grid k, and V.- = hourly volume of aircraft type i = VTO., + VL^ Step 42. Compute the total ground service vehicle emissions by grid by pollutant summing over all types of air- craft and ground service vehicles: EGSV, . = E £ EGSV. , , . kl i m imkl Emissions From Fuel Handling and Storage Step 43. Locate grid elements in which fuel is stored or handled. Step 44. Identify types of fuel and volumes stored. (Actual volume stored is classified. Assumed storage volume equals one month's supply at cur- rent usage rates.) 92 ------- Step 45. Determine the mean daily high, low, and medium temperature for the month of interest. Step 46. Determine the working loss factors for each of the three temperatures. Step 47. Determine the daily volume of fuel pumped. Step 48. Distribute the daily volume over 24 hours accord- ing to the diurnal flight activity pattern. Step 49. Compute working losses for the hour of interest according to the volume of fuel pumped and the temperature applicable to the time of day as: EFSIL - = emissions of pollutant 1 in grid k due to fuel storage and handling. Emissions from Engine Testing and Maintenance Step 50. Locate the grid elements in which engine testing occurs. Step 51. Determine the testing schedule (frequency and times of occurrence) for the different types of engines tested. Step 52. Determine testing cycle for each engine type. TT. = time-in-mode j for engine type n. Step 53. Apply the emission factors for the engine and modes to determine the emissions from engine testing: EET = TT. EF. , n jn jn ' where: EET = emissions from testing engine type n. Step 54. Determine the total emission factors from engine testing by summing over all engine types tested. EET = Z EET . n n If engine testing occurs during specific hours, apply the emissions to these hours. 93 ------- If it occurs randomly over a longer time period (e.g., an 8-hour working day, 24 hours, or a week), distribute the emissions equally over the time period. CIVILIAN AIRPORTS Emissions from Flight Operations at Controlled Airports Step 55. Identify the month, day of the week, and hour of the day for which emissions are to be estimated. Step 56. Determine the prevailing wind direction for the month. Step 57. Determine the active runway from the wind direc- tion and/or aircraft category. Step 58. For the time identified (Step 1), determine the activity factors for the different aircraft types: M. = percent of annual volume occurring during the month (aircraft category i), D. = percent of monthly volume occurring on the given day of the week (aircraft category i), H. = percent of daily volume occurring during the hour of interest (aircraft category i). Step 59. For the active runway determined in Step 2, locate the k grid elements through which aircraft pass. Step 60. Compute the air traffic volume for the hour from: A'M.-D.-H. V. (ODM) (106) where the factors are defined in Steps 3 and 6 and the subscript i refers only to general aviation aircraft. 94 ------- Step 61. For the different aircraft categories, activity volumes, and grid elements identified above, determine the j engine operating modes for each grid element. Step 62. Determine the time-in-mode for each aircraft category for each mode in each grid. = time-in-mode j for aircraft category i in grid k. Step 63. Identify the emission rates of the 1 pollutants, EFiljj °f tne different aircraft categories for the various engine operating modes. Step 64. Estimate hourly emissions for aircraft type i for each grid element: EAFO., , = V. EF., . T... ikl i ilj jik Emissions from Flight Operations at Uncontrolled Airports Step 65. Determine the annual volume of air traffic from FAA Form 5010 and discussions with airport per- sonnel. Step 66. Determine the prevailing wind direction for the month . Step 67. Determine the active runway from the wind direc- tion and/or aircraft category. Step 68. For the time identified for estimating emissions, determine the activity factors for the different aircraft types : M. = percent of annual volume occurring during the the month (aircraft category i) , D. = percent of monthly volume occurring on the given day of the week (aircraft category H. = percent of daily volume occurring during the hour of interest (aircraft category i). 95 ------- Step 69. For the active runway determined in Step 67, locate the k grid elements through which air- craft pass. Step 70. Compute the air traffic volume for the hour from: .. TT *" ----__ 1 (ODM) (106) ' Step 71. For the different aircraft categories, activity volumes, and grid elements identified above, determine the j engine operating modes for each grid element. Step 72. Determine the time-in-mode for each aircraft category for each mode in each grid. = time-in-mode j for aircraft category i in grid k. Step 73. Identify the emission rates of the 1 pollutants, EF.,. of the different aircraft categories for the various engine operating modes. Step 74. Estimate hourly emissions for aircraft type i for each grid element as; EAFO., , = V. EF.. . T... ikl i ilj jik Step 75. Compute hourly emissions from all aircraft in each grid element by repeating Step 74 for all categories : EAFO, , = Z EAFO., . kl i ikl Step 76. Locate grid elements in which fuel is stored or handled. Step 77. Identify types of fuel and volumes stored. Step 78. Determine the mean daily high, low, and medium temperature for the month of interest. Step 79. Determine the working loss factors for each of the three temperatures . Step 80. Determine the daily volume of fuel pumped. 96 ------- Step 81. Distribute the daily volume over 24 hours according to the diurnal flight activity pattern. Step 82. Compute working losses for the hour of interest according to the volume of fuel pumped and the temperature applicable to the time of day as: EFSH, - = emissions of pollutant 1 in grid k due to fuel storage and han- dling. 97 ------- SECTION IX IMPROVING ESTIMATES Table 4 (page 2) displays the percent of emissions contribution by source at 0'Hare Airport. Except for GO, aircraft are the predominate source of emissions, and even for CO they account for greater than two thirds. It is immediately evident then that an improved knowledge of aircraft opera- tions will offer the most improvement in emissions estimation. There is the added benefit that a better knowledge of aircraft operations will im- prove the estimates for ground service vehicles and fuel handling and storage, since these depend ultimately on aircraft for their employment. The first step would be to find precisely the volume and makeup of air traffic for a given hour. However, it is essentially impossible to pre- dict accurately what will occur in a given hour. Since this probably accounts for the greatest uncertainty in the hourly emissions estimate, the greatest improvement would come about from actually gathering data during the period of interest. After volume and makeup are known, the next important factor is time in mode, since this is the multiplying factor for a relatively constant emis- sion rate for a given mode. There is not likely to be much variation in takeoff, climbout, approach, or landing times for a given type of aircraft, more variation will arise from idle and taxi time differences although even these were found to be fairly standard upon observation. On this level of detail the actual pollutant for which emissions are being estimated becomes important. Idle and taxi modes have a relatively high 98 ------- emission rate for CO and hydrocarbons; NC> emissions are higher during X takeoff, climbout, and approach; and CO and NOX emissions are high during land ing. Airport emissions cannot be precisely estimated due to all the influencing factors described in Section III. It is felt that the methodology given in this report strikes a good balance between maximum potential accuracy and the rapidly increasing level of effort required as estimates become incrementally more precise. 99 ------- SECTION X REFERENCES 1. Allen, P. W. Regional, Air Pollution StudyAn Overview. Paper 73- 21, 66th Annual Meeting of the Air Pollution Control Association, Chicago, June 1973. 2. An Air Pollution Impact Methodology For AirportsPhase I. U.S. Environmental Protection Agency Report APTD-1470, January 1973. 3. Compilation of Air Pollutant Emission Factors. 2nd Ed.} U.S. Environmental Protection Agency, April 1973. 4. Official Airline Guide. The Reuben H. Donnelley Corporation, Oak Brook, Illinois, 5. Bogdan, L. et al. Analysis of Aircraft Exhaust Emission Measure- ments. Cornell Aeronautical Laboratory, Incorporated, Buffalo, New York, October 1971. 6. Elliott, George. Allied Aviation Fueling, Lambert Field, St. Louis. Personal Communication. 7. Climatic Atlas of the United States. U.S. Department of Commerce, Environmental Science Services Administration, Environmental Data' Service, 1968. 8. Bulletin on Evaporation Loss in the Petroleum IndustryCauses and Control. American Petroleum Industry, Bull. 2513, Washington, D.C., 1973. 9. Dziuban, Lt. Scott AFB, Personal Communcation. 10. Naugle, D. F. and B. T. Delaney. United States Air Force Aircraft Pollution Emissions. U.S. Air Force Report AFWL-TR-73-199, 1973. 11. Pratt Whitney, Hartford, Connecticut. Personal Communication. 100 ------- |