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Environmental Impact of Avgas Usage

The ICAO Committee on Aviation Environmental Protection (CAEP) recently made recommendations to reduce the impact of aircraft noise and engine exhaust emissions. Our government has accepted the principles outlined in the Kyoto Accord and will eventually focus itself on General Aviation activity. Over the long term pressure will be felt by the General Aviation community to curtail its activity in favour of the environment. We need to prepare our arguments to defend ourselves, but we also need to do our part to protect our environment.

Perhaps we can protect our environment by proposing a counter argument, or an alternative solution, a different focus. What we will not be able to do is to blame another activity or group of its waste. Rather, we might point to something inanimate, an attitude or a procedure.

For example, we might focus on the pollution caused by traffic STOP signs, often erected mindlessly in communities in an effort to slow traffic. These often unnecessary signs are an unconscionable waste of our declining, irreplaceable and increasingly expensive and polluting energy resources.

Letís take a look, through some rough calculations, at the extent of this waste:

If we agree that the automobileís share of the energy budget, (13%) is significant enough to warrant legislative action (e.g. lower speed limits), then, to be truly honest and concerned, we should look also at the other situations involving the automobile which are deserving of moves to economize. But what has been done? By industry? governments? people? you? me?

One litre of gasoline contains 30,000,000 Joules of energy. It can be calculated that an 1800 kg car accelerated to a speed of 50 km/h from a stop requires the input of 140,000 Joules.

If the total system were 100% efficient, the fuel consumed per stop and start would be 0.005 liters. However, because the system is only about 10% efficient, one litre yields only approximately 25 stops and starts.

On driving 10 km in my community, I have to negotiate 42 stops, almost all of which, (36) exist apparently to slow traffic. For me this means that 2 litres are wasted per day simply for stopping and starting, not counting the cost of fuel, of making and delivering replacement brakes, clutches etc., and the fuel expenditures of the people involved in the handling of these. Yet city planners mindlessly proliferate sprawling suburban settlements all growing their own crop of stop signs.

To look at the overall effect of untimed lights, needless stop signs, and poorly developed mass transit systems, let us look at the fuel wasted for a city of 2,000,000.

In my section of the city there are some 36 needless stops in 10 km. Assuming that is representative of the whole city, the 2000 km of road in this city should have 7200 stops. Assuming also that there are 300,000 vehicles in operation, and that each vehicle travels 10 km a day, one can project 10,800,000 needless stops per day. At 25 stops per litre, that means 432,000 litres wasted directly each day, aside from other indirect associated costs in fuel! The pollution of that fuel, one litre per 25 cars stopping, is dumped into the air at the stop sign in front of your house. And what of the other pollutants, brake pad asbestos and the like, produced by the rest of the car at each stop sign!

The point is that before we should submit to the publicís argument that our flying unnecessarily pollutes the environment we should point to more immediate solutions which will not discriminate one sector alone.

Aviation has made great strides in conservation. We use simulators to replace flying aircraft. We have GPS for direct flights. Engine instruments permitting optimal leaning. Super smooth composite aircraft. Lighter weights. Electronic equipment which draws less power. Better maintenance of the airframe reducing air leaks and therefore fuel burn. Larger aircraft have increased their fuel efficiency 70% since 1970 by a variety of improvements.

We need not hang our heads and feel to be pariahs needing to hide. Nor do we need to allow our flying activity to be singled out. Letís develop meaningful arguments before we have to defend our flying.

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Frank Hofmann
Director, COPA
ICAO Observer for IAOPA
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