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Old 11-04-2009, 09:18 AM   #9 (permalink)
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Airplanes can choose their speed and altitude, so they can adjust their situation to their best BFSC map and get great mileage, if they are designed for that purpose and can climb high enough.

Much of this same technology can be used in cars, as long as you disconnect the engine from the wheels. While the airplane can use altitude to store energy, cars can use hills for the same purpose, but with cars you have to be lucky enough to find the right hill.

The motor gliders are superb examples of P&G in airplanes, especially if they can find a thermal, which is similar to a draft in a car.

I have thought about a hydraulic power boost for takeoff in an airplane, so the engine size could be reduced,

We used to catch Mallards in a jon boat with a crab net. If you chased them, they would take off and land a few hundred yards away. After 3 or 4 chases they were too exhausted to get off the water and they would go underwater, and we would scoop they up with the crab net.

The point is they used so much more energy taking off than it took to maintain flight it was easy to take them alive.

I believe the same applies to vehicles, and the practice of having giant engines to allow acceleration. Short term energy high capacity energy storage for the seldom encountered surges of power necessary to drive, would allow much smaller engines to do the job. If steep grades were an issue the some form of pressurized induction would allow speed to be maintained on steep grades.

regards
Mech
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