Can a Modified Helicopter Double as an Airboat?

[Overlimit]

Hello everybody!

Let me share one of my ideas with you!

This is a modified helicopter. It has raft instead of wheels. Its screw axis can tilt. So may be this machine can both fly and travel on the water surface.

Please comment.

 

[Burnerjack]

Suggest you search the term "airboat".

 

[Overlimit]

TYVM, Burnerjack. I edited my post.
http://en.wikipedia.org/wiki/Airboat

Sorry for rough scetch.

 

[Overlimit]

Upper screw vanes can rotate 180 deg. in order to force air to go other side.
Watercopter is a name I invented for this transformer.

Please vote!

 

[Burnerjack]

Couldn't give a qualitative comment based on the drawing/description provided. However, you may wish to research the development of the modern helicopter design. I kind of remember something about a grave, inherent instability issue until the rotors were allowed to pivot in relation to the shaft.
One added point: if you were to use this kind of like a helicopter but in contact with water, the source of thrust will not be on the same plane as the drag (if I understand your drawing correctly). The result would be an induced pitching moment that would push the nose downward. Imagine someone on a skateboard with a fan on their back. All but small amounts of thrust would most likely result in a 'faceplant'.
For surface craft, the aforementioned airboat is good because it will glide over most surface level obstacles.
For aircraft, remember "That which goes up, will come down at 9.9m/sec^2, or faster." You may think about leaving such designs up to the 'Big Guys'. Getting hurt is no fun (ask me how I know...), hurting someone else is far worse.

 

[Overlimit]

Many thanks for your comments, Burnerjack. I think I understood pitching moment problem. This hybrid might be very unstable.

 

[Burnerjack]

You're very welcome. BTW, while not new nor a helicopter, for near surface travel you may want to investigate the Russian Ekranoplan. This is a ground effect vehicle that has been scaled down to something like 4m wingspan with small gas engine. While not new, you may find it educational and exciting. Good luck and stay safe.

 

[Overlimit]

WC

Watercopter V. 2.1

2BJ: I don't think pitching moment is a problem because friction force is small.
Please, criticize next version.

http://en.wikipedia.org/wiki/Ground_effect_vehicle

 

[berkeman]

Welcome to the PF, Overlimit.

We do not generally allow polls in the technical forums, so I've closed your poll. Keep on thinking up creative ideas!

 

[Burnerjack]

Looks like an airboat to me. I guess all I can add is "if the drawing board shows no significant flaws, time to move to the scale model design phase." Good luck. Remember, if knowledge is gained, there are no 'failed' experiments.