writes:
Having become dangerously addicted to MS Flight Simulator, I am
starting to develop a hankering to learn to fly for real. However I'm
having a bit of trouble reconciling this desire with my concern about
CO2 emissions and climate change. My wife and I tend to buy reasonably
fuel efficient cars and are soon to have a wind turbine installed on
our house, so to start burning aviation fuel just for fun would seem
like a bit of a step in the wrong direction.

Can anyone provide any insights to help me allay these concerns? I
don't even know how much fuel the average light aircraft consumes or
how much CO2 it puts out into the atmosphere. Is it comparable to a
car or is it a lot more? (My car gets about 50mpg, but then I spend a
lot more time driving it than I could ever afford to spend flying a
plane.)

Sorry to say, but most small airplanes burn more fuel than your car.
Also, due to their older engine design, most burn leaded fuel.

One datapoint: the plane I am training in, a Piper Tomahawk, burns 6.5
gallons of 100LL fuel per hour, holds two people, and cruises around
110mph. So that is roughly 17mpg. There are more efficient planes
(for example, I think the Diamond Katana burns less gas), and there
are less efficient ones (to overgeneralize, faster == more gas, and
older plane == more gas).

I justify my flying to myself by arguing that I fly many fewer hours
per year than most people drive (I use my bicycle as my main form of
transportation). But it is somewhat hard to make a solid
environmental argument for any form of recreation which burns gas.

Chris