On Apr 15, 12:08 pm, Le Chaud Lapin wrote:

I'm already spending too much time thinking about this, but if I were
to have a go at it, right now, I would aim for:

1. One seat-only, initially.

Mm. Utility.

2. Structural symmetry throughout, whenever feasible.

Symmetry often means simple which in turn often means heavy.
Bridges are complex affairs to save weight so they don't collapse
under their own mass. The lightest and most useful airplanes are
usually rather complex structurally.

3. Inexpensive USB-based COTS sensors everywhere.
4. Inexpensive USB-based COTS controls everywhere.
5. Elimination of conventional ICE and prop. [Biggest impediment to
flying car, in my not-sufficiently-educated opinion].

So, electric, which is really heavy and has short range, or a
turbine, which makes the money saved using COTS sensors look tiny
indeed. Or were you maybe thinking nuclear?

6. Even weight distribution. Ideally, the aircraft would have a box-
like structure.

Drag, big time. Corners, even corners aligned with the flight
path, create drag. Even weight distrubution will mean CG problems, or
spin recovery issues.

7. Glass-cockpit everything with marginal cost of $1000 for
commodity CPU. *No more* Garmin.
8. Pressurized cabin.

Weight. Lots of weight. The systems to control it weigh more,
too. A fuselage strong enough for pressure is considerably heavier
than its non-pressurized counterpart.

9. Computer assisted take-off, computer assisted approach, computer-
assisted stabilization, computer-assisted tracking.

Might as well leave the pilot on the ground. Why bother
learning to fly? Besides, there are already too many people driving
airplanes that know too little about flying.

10. Ultralight components (no pun intended). I see no fundamental
reason that a 100kg man should ride in 1000kg vehicle. Use plastic and
other frilly components if doing so does not compromise structural
integrity or pilot safety.

Already been done. Leeon Davis designed a single-seat airplane
that weighed 177 lb and was powered by an 18 HP Briggs industrial
engine. Clocked well over 100 mph.

12. Abnormally-scary dependence on fly-by-wire. If it can me made
electronic instead of mechanical, make it so.

What are you saying? Fly-by-wire is scary but we'll make it so
anyway?

13. Basic safety features (parachute, auto-oxgen, auto-extinguisher,
auto-pilot when computer senses that pilot is incoherent)

Parachutes weigh something and take up considerable room.
Oxygen tanks are heavy, too and take up more room. Where is the pilot
supposed to go in this little airplane? And what is he doing in it
when he's incoherent? And what happens if the computer incorrectly
decides he's incoherent and takes over just when the pilot, who sees a
danger approaching, decides to avoid that danger and the computer
decides NO?
The Piper Arrow had an automatic gear-extension system to
prevent the pilot from landing gear-up. It sensed pitot pressure and
dropped the gear below a certain airspeed. Trouble was that this
"safety feature" killed a few folks when the pitot tube iced up and
the system thought airspeed had dropped, so it lowered the gear,
adding drag and another ice-catcher just when the pilot was struggling
to stay airborne long enough to get out of the ice. These automatic
systems sound nice until the unforeseen occurs. Those unforeseen
things are why it's harder to get a pilot's license than a driver's
license. You have to know what's going on.

14. Convenient means of entry an exit. Grandma should not have to
mount the wing.


Good luck. Structural nightmare. The Cessna Cardinal successfully
addressed this back in 1968, but the weight penalty was significant.

15. Efficiency - all that heat lost by ICE, plus 20% loss due to prop
twisting air, plus unnecessary weight from all those mechanical
components that could just as well be made of plastic actuators.

Fantasy. Like I said, find those new technologies. As far as
plastic goes, the Boeing 787 is mostly plastic but its control are
metal. Plastic does not do well handling hot hydraulic fluid.

15. Leather seats.

Weight.

16. Luxury sound system including digital radio.

More weight. And a distraction. Stay at home in your living room.

17. Video-games (including Microsoft Flight Sim).

Now there's an intelligent thing. Flying while pretending to
fly.

18. Inter-aircraft communication using WiMax (or something similar).
Proximity detectors, etc.

Weight. Complexity. Expense.

19. Pre-heating and pre-cooling of cabin.

With what? Heaters and air conditioners weigh a lot.
Especially air conditioners.

20. Three-liter water tank with spigot on dash.

Another eight or nine pounds.

21. Air conditioner.

See above.

22. Integration of all instruments into computer monitors with few
exceptions (backup compass, backup altimeter, backup etc.)

Been done.

23. USB camera mounts around the aircraft
24. Electronic megaphone for voice communication to those in immediate
vicinity of aircraft.
25. Real-time capture of all flight data in minutest detail onto
sealed hard disk for when it crashes.
26. Elimination of rudder control with foot pedals. Computers should
make this unnecessary, right?

Someone is lazy.

27. Significant reduction in sound pollution.

Mufflers. More weight.

28. Rear-mounted fuel-tank.

So fuel splashes forward over everything when the airplane
ccrashes, and so that the CG wanders all over the place as fuel is
burned.

29. Trash bin.

The whole design should go into this trash bin.

30. Order of magnitude more control over the orientation of
aerodynamic surfaces. [IMO, this represents and *enormous* opportunity
reduce requisite skill in flying aircraft].

OK. Design an "airplane" with all those goodies, and see
just how heavy it will be. It'll have a stall speed in the range of
120 MPH. Even the 1000 kg airplane that carries the 100 kg man, the
airplane you think is inefficient, already exists and has some of the
above goodies. That's why it weighs so much and can carry so little.

You forgot de-icing systems.

Dan