aircraft CO2 emissions

[excess_3]

the easiest way to decrease CO2 emissions
is to design aircraft to fly at a slower speed,
for example, to cruise at Mach 0.75 instead of the more
typical M 0.85 to 0.89.

there would be many benefits,
fuel savings, weight savings, lower landing speeds,
etc, etc.

another thing to look at, turboprops instead of jets.
there would be many benefits, among them
would be more noise and vibration in the cabin.
.....................................................

of course, the jet-set greenies would complain
about wasting a few minutes of there time

[obliviously]

1. Crickets

Cheer up! There will be other Ideas!

[Nihil]

2. Disagree.

> the easiest way to decrease CO2 emissions
> is to design aircraft to fly at a slower speed

Having had a lot of contact with the aircraft design cycle in the past,
that is probably one of the hardest ways to do it. If you realised quite
how long it takes to go from the initial design idea through to the sale
of the first plane, you wouldn't even have suggested that.

On the other hand, the *really* easy way to decrease the aircraft
contribution to global CO2 output is to stop flying so damn many of
them every day. As seen just over 8 years ago, this decision can be
implemented by a country to a draconian level in a single day so taking
a more moderate approach (say cutting 15% or so per year) would still
have achieved far more of a reduction before any modified design would
even be submitted for certification (never mind be available for use).

:hi:

[phantom power]

3. What fraction of total GHG emissions do airplanes represent?

[GliderGuider]

4. Aircraft use about 1.3% of all petroleum consumed.

According to my calculation derived from data here: http://www.airlines.org/economics/energy/MonthlyJetFuel.htm

It's not exactly low-hanging fruit.

[excess_3]

6. closer to 7 percent of US petroleum used

keep in mind that the vast amount of
air travel/freight is unnecessary

[kristopher]

5. They represent a class of energy users that require the energy density of liquid fuel

Solve the problem for airplanes and you will quite possibly solve the problem for ships, heavy equipment (including farming), etc.

IIRC the entire class represents about 30-40% of fossil fuel consumption.