Green Flight

Copyright 2009 by Paul Niquette. All rights reserved.

light is supposed to be fast -- faster, certainly, than other modes of transportation.  "Faster the better," we say.  Flight has been optimized for fast.  The Jet Age sure did give us faster ways to get from where we are to where we want to be.  The Jet Age did such a good job of it that for many journeys, flight has become the only practical mode of public transportation, displacing trains and buses and ships.  Fast has its costs, though...
Energy Consumption and Environmental Damage.
The world is gradually becoming sensitized to both of these matters in all realms of human activity.  Saving energy and protecting the environment have emerged as international priorities.   Whereas new technologies are needed -- hoped for! -- conservation appears to be the most practical mitigation for the near term and beyond.  One thing must be clear to everybody: Flight cannot benefit directly from many promising new technologies: fission and fusion, geothermal and solar-thermal, hydroelectricity and tides, hybrids and photovoltaics -- least of all wind.  Meanwhile, the wheels seem to be coming off of the biofuels bandwagon...
If it takes more than one unit of energy from either petrofuel or biofuel to make one unit of biofuel, what's the point?
-- Paul Niquette, Sophisticated: the Magazine

...a severe set-back for alternative aviation fuels.  Conservation, then, is key.  "Going green" means giving up what flight does best.  "Faster the better" won't -- well, fly.

After pushing back from the gate, taxiing to the runway, and waiting in line for departure, an aircraft must conduct three fundamental phases of flight: [1] take-off and ascend to cruising altitude, for terrain avoidance and favorable winds, [2] cruise in level flight, preferably along the most direct route, and [3] descend for the approach to landing. 

Flight routinely uses maximum allowable power -- pushing the envelope -- for all three phases, even flying in a shallow power-dive during descent top-of-the-green, all of which, of course, consumes the most fuel.  Flight will do all of that to optimize for fast.

What must Green Flight do to optimize instead for conservation