"TRB's Airport Cooperative Research Program (ACRP) Report 97: Measuring PM Emissions from Aircraft Auxiliary Power Units, Tires, and Brakes presents the results of a comprehensive test program designed to measure particulate matter (PM) emissions from auxiliary power units and from tires and brakes during the landing phase of operations of in-service commercial aircraft. The research results are designed to provide a significant contribution to the characterization of emissions from these sources with the goal of helping airports improve the accuracy of their PM emissions inventories."--Publisher's description.

This report is the product of a 2-year emissions testing program designed to document, characterize, and evaluate emissions from sixteen aircraft engines, two helicopter engines, and two auxiliary power units (APUs) burning JP-8 fuel. The purpose of this engine testing program was to develop emission factors for the tested engines under representative engine load conditions. All testing was performed by the Environmental Quality Management Inc. (EQ) and Roy F. Weston, Inc. (Weston) team. Testing was conducted for criteria pollutants and select hazardous air pollutants (HAPs), e.g., aldehyde/ketones and semi volatile and volatile organic compounds.

The Report is the product of a five year emissions testing program designed to document, characterize, and evaluate emissions from aircraft engines, auxiliary power units (APU's) burning JP-8. The purpose of the emissions testing program was to develop emission factors for the tested engines under representative load conditions. This addendum is for the PT6A-68 aircraft engine test program. Testing was performed by Environmental Quality Management, Inc. (EQM). Testing was conducted for criteria and hazardous air pollutants.

The Air Quality Facility of the John A. Volpe National Transportation Systems Center is providing support to the Emissions Division of the Federal Aviation Administration's Office of Environment and Energy (AEE-300). As part of this support, the Air Quality Facility is conducting a comprehensive review of past research in the area of aviation- related particulate matter. The purpose of this literature review is to allow an informed decision to be made on a possible first-order approximation to predict the mass of particulate emissions from aircraft until such time that measured data are available for most aircraft. Available references included in this report were collected from public and private libraries, technical journals, project reports, electronic literature searches, interviews, and other key sources. It should be noted that the literature review is not all- inclusive and that emphasis was placed on information concerning measured mass data from aircraft. Following the literature findings, a first order approximation methodology is suggested to estimate the mass of particulate matter (PM) emitted from aircraft based on available data.

This AIR describes procedures for calculating emissions resulting from the main engines of commercial jet and turboprop aircraft through all modes of operation for all segments of a flight. Piston engine aircraft emissions are not included in this AIR. Some information about piston engine aircraft emissions can be found in FOCA 2007. The principal purpose of the procedures is to assist model developers in calculating aircraft emissions in a consistent and accurate manner that can be used to address various environmental assessments including those related to policy decisions and regulatory requirements.The pollutants considered in this document are: Nitrogen Oxides (NOx) Carbon Monoxide (CO) Total unburned Hydrocarbons (THC) Carbon Dioxide (CO2) Water (H2O) Sulfur Oxides (SOx) Volatile Organic Compounds (VOC) Methane (CH4) Non-Methane Hydrocarbons (NMHC) Non-Methane Volatile Organic Compounds (NMVOC) Nitrous Oxide (N2O) Particulate Matter (PM2.5 and PM10)As indicated above, hazardous air pollutants (HAPs) are not individually accounted for; many of these are simply included as part of THC. Also, trace metals are not included other than those that may already be accounted for as part of PM emissions. Since the scope is limited to aircraft engine emissions only, emissions from Ground Service Equipment (GSE), roadway vehicles, power plants, training fires, etc., are not included within this document. Athough Auxilliary Power Units (APU), brakes, and tires are also part of the aircraft, their emissions (e.g., tire wear) are not within the scope of this document.The methods are based on aircraft performance and emissions modeling. This means that only the pollutants exiting the exhaust of an engine are considered. Any atmospheric effects including those that occur in the near-field (e.g., exhaust plume) and the subsequent atmospheric dispersion are not modeled. The exception to this is in the computation of PM emissions.In meeting the needs of modelers who may have varying fidelity requirements for both emissions and aircraft performance modeling, this document does not try to promote a single database and methodology. Therefore, several methods have been included in this document as indicated below with the emissions methods categorized by pollutants: Emissions Modeling Methods NOx, CO, and THC P3T3 Boeing Fuel Flow Method 2 (BFFM2) Deutsche Forschungsanstalt fur Luft- and Raumfahrt (DLR) Method International Civil Aviation Organization (ICAO) Reference Method CO2, H2O, and SOx Fuel Composition Method (FCM) VOC, NMVOC, CH4 and NMTHC Derivative Factor Method (DFM) N2O Approximate Factor Method (AFM) PM2.5 and PM10 First Order Approximation (FOA) Aircraft Performance Methods Aircraft performance data from flight data recorders Manufacturer aircraft performance models SAE AIR 1845 combined with Eurocontrol's Base of Aircraft Data (BADA) Eurocontrol's BADA Other aircraft performance models such as the Project Interactive Analysis and Optimisation (PIANO) toolBoth of these sets of emissions and aircraft performance methods are listed in the order in which they are presented in this document. And as previously indicated, the order generally denotes the level of accuracy where the first method in each section represents the most accurate method based on current understanding. The exceptions to this are:Emissions Methods BFFM2 DLRAircraft Performance SAE 1845 + BADA BADAThe ordering of these methods are arbitrary since they are considered comparable (e.g., BFFM2 is comparable to DLR). One other possible exception is the last listing under aircraft performance methods ("Other aircraft performance models"). The data from these other sources may be more accurate, comparable, or less accurate than the previously mentioned methods. This last category was added to include all other methods that were not based on manufacturer, SAE 1845, and BADA models.In order to provide a better understanding of the relative condition of these methods, they have been defined into development status (i.e., "mature" or "developing") and fidelity (i.e., "simple," "intermediate," or "advanced") categories as presented in Table 1. The "other" aircraft model category was not included in Table 1 since it is understood that it can be listed in any of the categories depending on which method/model is employed. The definitions for each of the categories are as follows: In modeling aircraft performance and emissions, the main focus is on a single flight. This includes the complete operation and movement of the aircraft from gate-to-gate: Main engine start-up Ground taxi-out and delay activities Takeoff: Runway roll Takeoff: Initial ascent Climbout En route/cruise Airborne delay activities Approach Landing roll Thrust reverser Ground taxi-in and delay activities Engine shut-downFor modeling purposes, these modes can generally be simplified so that they are equated to one of the four LTO modes. Depending on the method, the actual modeling of the gate-to-gate movement may involve a segment-by-segment approach where results can be integrated to obtain totals by mode and flight. Currently, the AIR does not address emissions during engine start-up and shut-down activities. Also, thrust reverse operations are not directly covered in this AIR. This Aerospace Information Report (AIR) describes procedures for calculating emissions resulting from operations of jet and turboprop aircraft through all modes of operation. The procedures assume that reference emissions and performance data are available for each airplane involved. The fundamental element of the procedures is a method for deriving emissions indices for an airplane when performing any specified operation for a segment of a flight. The principal purpose of using the procedures is to assist model developers in calculating aircraft emissions in a consistent and accurate manner that can be used to address various environmental assessments including those related to policy decisions and regulatory requirements.Rather than presenting one method, many viable methods are presented for both emissions and aircraft performance modeling with descriptions of the uncertainties involved. As a loose guide to the user, the methods are also ordered such that the most accurate methods are presented first in each section based on current understanding. This document is intended to be updated periodically. Hence, the methodology descriptions and uncertainty assessments will be modified accordingly as the various methods evolve and new information becomes available.