General Aviation and Air Emissions

Recent chatter in the Rec.Aviation.Homebuilt newsgroup indicated to me that little is generally known about the impacts, and potential for regulation of General Aviation with regards to air pollution. I know a little bit about this issue, so I thought I'd share.

Aviation in general can have some pretty signifigant local impacts on air quality. The Natural Resources Defense Council, who has the best lawyers and scientists of all the big Environmental activist groups, has done an fairly exhausive (pardon the unintented pun) report on the subject. General Aviation, however, has a tiny, tiny impact.

The Clean Air Act of 1964 is the Mother of All Air Pollution regulations, and the reduction goals it set, that we haven't reached, are the reason for catalytic converters on weed whackers and regulation of charcoal lighter fluid. It's my belief that regulation will come to us, eventually.

The EPA has dicked around with the idea of regulating piston General Aviation engines, currently, we're un-regulated.

The specific question in RAH was about 2 stroke engines. If the EPA should decide to regulate them, I'll be the regulations will look a lot like the Marine Engine regs.

The remainder of this page is the outline for a talk I gave at a local pilot's group about 4 years ago, when the EPA was threatening to regulated General Aviation in California as part of something called the Federal Implementation Plan. The States are supposed to come up with implementation plans, but California, under our last two Republican governors, was dragging it's feet. The Sierra Club sued the EPA for failure to enforce the Clean AIr Act, and won big. The EPA formulated the FIP as a stick to bet the statehouse with. It was never intended to be implemented, but it scared many in GA. I think the EPA learned a lot from the blizzard of public comments that this exercise produced. In the end, the State did come up with an acceptable plan, and the FIP got shredded.


1. Introduction

1.1. How I got into this / Exposure of my biases

1.2. My main points

1.2.1. Air pollution is a problem that affects us all, and is not getting better fast enough to protect our health and economy.

1.2.2. Personal Aviation will be affected by Clean Air Act.

1.2.3. The California Draft Federal Implementation Plan is a red flag, and is not likely to be enacted in it's present form

1.2.4. We will have fuel - film at 11

1.2.5. We, the personal aviation community, should be vigilant and get organized

2. Air pollution is a problem

2.1. Primer on air pollution

2.1.1. The constituents of air pollution - VoC's, Nox, particulates, lead, carbon monoxide, Sulfer dioxide, Ozone.

2.1.2. 3/4 of all Californians are exposed to air that is a hazard to their health.

2.1.3. Those most at risk are often receiving the highest exposures - children in particular, but the poor, and elderly also are at risk.

2.2. Aviation's contribution

2.2.1. The nature of piston aviation engine pollution. Cool, rich combustion (required due to air cooling, low gas volatility, and poor induction systems) means not much NO , but lots of VoC. Other problems include freely vented gas tanks, gas sampling, and crankcase breathers. A GA engine is hundreds of percent dirtier than a car engine.

2.2.2. Emissions standards for G/A were proposed in 1973, but were withdrawn. Very little research has been done. New Jet engines have to meet international standards.

2.2.3. All of aviation together contributes about 1% of Southern California's air pollution, and General Aviation contributes about 20% of the VoC and 1% of the NOx from that.

3. The California Federal Implementation Plan

3.1. The FIP in brief

3.1.1. "Under the Clean Air Act, state and local agencies are required to develop long-term plans to show how they will achieve safe, clean air by specific dates. State and local environmental agencies in California have traditionally been national leaders in the area of air-quality control efforts. However, in recent years these agencies have not successfully enacted plans demonstrating how they will meet the Clean Air Act's standards for public health. As a result, the U.S. EPA has been ordered by the courts to craft federal implementation plans (FIPs) to ensure that someone provides overall clean air plans in the South Coast, Sacramento, and Ventura areas."

3.1.2. All sources of air pollution must contribute to a solution. FIP attacks all point and mobile sources. Rail, trucks, ships, recreational boats, motorcycles, non-road engines, and requires reductions from them all. Given that by 2010, the target areas population will be 23 percent higher, automobile miles 65 percent higher, AND pollution must be reduced by 2983% of CURRENT levels, only an approach that looks at everything has any chance of succeeding.

3.1.3. Control Strategies are carefully tailored to each sector, and must consider costs of implementation.

3.1.4. Fees are considered a last resort. Fees imposed by the Feds cannot, by Federal law, go anywhere but into the general fund. State and Local fees can be directed to special accounts or uses. Fees are based on total cost to society per ton of pollutant. I.E. About $30/per gallon of spilled gasoline, or about a buck per spilled fuel sample.

3.2. The plan for general

3.2.1. EPA's problems in formulating a strategy FAA regulations, low turnover of existing fleet.

3.2.2. Two roughly similar approaches examined: Surcharge on gas, and fees for operations. Both designed to reduce the number of operations. New technology, clean engines would be exempt.

3.2.3. Actual implementation of this part of the plan not until 1999

3.3. the Response

3.3.1. The state - I have no details, the Governor is stalling, awaiting an independent economic analysis

3.3.2. The local AQMD's - Ventura County basically left GA alone, not enough of a problem to be worth addressing. No details on SCAQAMD or SAQMD.

3.3.3. The aviation community AOPA

A. Hates fees

B. flight hours are declining anyway, already producing the reductions called for. These reductions are likely to be permanent.

C. Changes in ground operations can produce further reductions, I.E. vapor recovery when filling tankers and storage facilities, and possibly closed venting add- on devices for planes on the ground.

D. Education can help pilots fly cleaner changing pre-flight practices, leaning on the ground. EAA - basically the same

A. less enthusiastic about vapor recovery from planes on the ground

B. Notes that GAMA proprietary data shows GA engines are getting cleaner, and electronic engine controls will help and are in service now in Experimentals.

C. The court decision did not require GA reduce emissions, just that emissions get reduced. EPA should support research if they want GA to share. Individuals - quite a lot of inflammatory rhetoric at public hearings.

3.3.4. EPA's reply - we've learned a lot about aviation, thank you. Now let's hope the local authorities do their job.

4. The Story of Aviation Gasoline

4.1. The history of leaded AvGas

4.1.1. There were no special regulations or requirements for aviation gasoline or aircraft engine gas requirements prior to 1946. Most airplanes used unleaded, straight run gasoline. Engine manufacturer's went so far as to prohibit the use of leaded gas in their engines due to the deposits it left, and the use of inferior feed stock it allowed. Without detergent oil, and with low-tension magnetos, the engines couldn't handle it.

4.1.2. Highly leaded gas was developed to allow a high degree of of compression and supercharging - WWII created a huge demand and an industry response to fill it.

4.1.3. After the war, the oil companies threatened to dismantle this infrastructure. The Air Force still needed high octane gas for the post-war air force, which still relied on piston engines. The CAA, in collusion with the DoD, decided to require certification of new aviation engines to use this type of gas to provide a steady market, and to keep the infrastructure there in case of another war.

4.1.4. Gradually, engine manufacturer's learned to use this new gas (100 octane) to advantage, and gradually came to depend on it.

4.1.5. The industry itself created 10011 for it's own reasons. Highly leaded fuel was a potent contaminant now that leaded car gas was dead. Only 2 sets of tanks, trucks, eta for aviation instead of 3.

4.2. AvGas present

4.2.1. The demise of the piston engine fighter, military transport, and commercial airliner made AvGas a specialty product, albeit a potentially profitable one.

4.2.2. General Aviation is now the largest mobile source of lead.

4.2.3. Present day AvGas is probably just car gas with lead. Further, it is probably oxygenated gas as well. Tieback into the FIP.

4.3. AvGas future

4.3.1. The 1990 Clean Air Act was a wakeup call, scaring the industry into action.

4.3.2. No one knows what octane is truly required of most engines. Testing is being undertaken by the FAA.

4.3.3. Future gas will look a lot like present day premium unleaded.

4.3.4. Controversy over how high to go. EAA: 96 octane is high enough. High compression/heavily supercharged can cope with water injection, ignition mods, and/or operational adjustments. Make them with the fancy wallets and fancy engines pay the price of those goodies, don't make the rest of us subsidize their oddities. NBAA & AOPA: No mods to anybody.

4.3.5. Distribution: Good News/Bad News AvGas to Car Gas wholesale differential will drop, perhaps drastically Environmental compliance, higher labor costs, and a flat or shrinking market will mean more Self-Service, fewer goodies, unbundling services, and fewer outlets. By 2000, there will be only 2000 FBOs to service 6000 airports.

5. Conclusions

5.1. Reiterate main points

5.2. My own behavior has changed

5.2.1. I was taught from day one to lean on the ground.

5.2.2. I no longer throw out clean fuel samples

5.2.3. My airplane will have electronic engine controls, closed crankcase venting, and closed fuel venting.