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> Wow, that’s a hilarious stat. How is that even… possible? There's nothing magical about flight. Take-off takes a bunch of energy. Maintaining that energy, n

> Wow, that’s a hilarious stat. How is that even… possible? There's nothing magical about flight. Take-off takes a bunch of energy. Maintaining that energy, not so much. Planes are pretty aerodynamic, imagine that :) Some are much lighter than cars since every pound counts. To the point that people often opt to not have AC (if it's even an option) to save a few pounds. They will cover a lot of ground in the same amount of time. That helps even more. Not all planes are that economical, of course. But some are indeed hilarious. Check ultralights (or microlights as they are known in Europe).

bombcar 4y ago
A/C is amusing because it’s only needed on the ground - once you’re at cruise you can just open the window if it’s too hot - the outside air temp will almost always be pretty Low.
midoridensha 4y ago
>There's nothing magical about flight. Take-off takes a bunch of energy. Maintaining that energy, not so much. Yep, take-off and ascent burns a lot of fuel, much more for the time duration than cruising. It's too bad there isn't a way of recovering some of that energy when descending, similar to how electric cars recover energy when braking.
- ryandrake 4y ago
  > It's too bad there isn't a way of recovering some of that energy when descending, similar to how electric cars recover energy when braking. A descent is a pretty efficient conversion between potential energy (altitude) and kinetic energy (speed/horizontal distance) so you get it back. Your RPM difference between cruise and descent is a proxy for your recovered energy. An engine out glide/landing is the extreme demonstration of this.
- weberer 4y ago
  >It's too bad there isn't a way of recovering some of that energy when descending But that's exactly what happens already. Point the aircraft down and it will pick up speed.
  - thfuran 4y ago
    But you don't tend to want to land at enormous speed.
    - sokoloff 4y ago
      That’s not an issue. My typical cruise descent profile on a VFR flight is to roll in a small amount of nose down trim and fly at full cruise power around 300 feet per minute for most of the descent, using the stored potential energy to increase speed. Nearer the airport, I’ll make a power reduction and continue to convert that potential energy to forward travel, eventually putting out gear and flaps. There’s more than enough drag for any reasonable descent profile to allow the potential energy to be used to move forward without gathering excessive speed. Power off, I can glide around 1.5 nautical mile for every 1000’ of elevation I have to use.

bombcar 4y ago

A/C is amusing because it’s only needed on the ground - once you’re at cruise you can just open the window if it’s too hot - the outside air temp will almost always be pretty Low.

midoridensha 4y ago

>There's nothing magical about flight. Take-off takes a bunch of energy. Maintaining that energy, not so much. Yep, take-off and ascent burns a lot of fuel, much more for the time duration than cruising. It's too bad there isn't a way of recovering some of that energy when descending, similar to how electric cars recover energy when braking.

ryandrake 4y ago
> It's too bad there isn't a way of recovering some of that energy when descending, similar to how electric cars recover energy when braking. A descent is a pretty efficient conversion between potential energy (altitude) and kinetic energy (speed/horizontal distance) so you get it back. Your RPM difference between cruise and descent is a proxy for your recovered energy. An engine out glide/landing is the extreme demonstration of this.
weberer 4y ago
>It's too bad there isn't a way of recovering some of that energy when descending But that's exactly what happens already. Point the aircraft down and it will pick up speed.
- thfuran 4y ago
  But you don't tend to want to land at enormous speed.
  - sokoloff 4y ago
    That’s not an issue. My typical cruise descent profile on a VFR flight is to roll in a small amount of nose down trim and fly at full cruise power around 300 feet per minute for most of the descent, using the stored potential energy to increase speed. Nearer the airport, I’ll make a power reduction and continue to convert that potential energy to forward travel, eventually putting out gear and flaps. There’s more than enough drag for any reasonable descent profile to allow the potential energy to be used to move forward without gathering excessive speed. Power off, I can glide around 1.5 nautical mile for every 1000’ of elevation I have to use.