Heresy and VTOL

[Rotor Rooter]

This forum is about low-cost rotary wing aircraft.

However, for the fun of looking outside the box, here is a concept for consideration;

Airplane with Near VTOL (http://www.unicopter.com/1492.html)

Dave


Should a discussion about fixed-wings be considered as heresy, the following will be understood. :)


http://www.unicopter.com/Closed.gif

[rtfm]

Nothing wrong with discussing fixed wings on a gyro forum, mate. As I see it, fixed wings on gyros are going to make a major comeback, when it becomes more widely recognised that gyros can transition from autorotative flight to fixed wing flight (eg: Carter Copter) without too much fuss.

Regards,
Duncan

[Ga6riel]

Bartini's VVA 14 and its successor the MIP were intended to use VTOL but only in ground effect. This is a simpler/safer solution as, it requires less power and implies less technical and practical risk.

His machines would lift off verticly, transition into ground effect, and then transition into free flight, and could do the same on landing. There are a few secrets however in the location of the CG to CL relationship that Bartini cleverly overcame with the VVA planform.

pictured is an impression of MIP inflight, and a VVA hull at Monino near Moscow, sans the wings and PAR engines

[Rotor Rooter]

Rtfm,

A thousand people ~ a thousand opinions, however, IMO the incorporation of wings and rotors in the same craft will never become viable. Higher speeds dictate stronger rotors. By adding sufficient strength to the rotors, you eliminate the need for fixed wings.

The revitalization of Sikorsky's Advancing Blade Concept (http://www.synchrolite.com/0890.html) is a step in the right direction.

This concept (http://www.unicopter.com/1093.html), by the aerodynamist Stepniewsk, is even better.


Ga6riel,

Anougther interesting concept. http://www.unicopter.com/ThumbsUp.gif

Dave

[Ga6riel]

yeah, in the cloistered world of soviet design bureaus I have an enduring respect for Bartinis work. Aware that ground effect machines are most suitable for over water use, therefore logicaly amphibians or flying boats. He neatly avoids consuming 20% of the AUW with hull strengthening by going VTOL in the smallest way he could manage.

While other bureaus managed 6ft in ground effect, Bartinis vastly smaller rig could manage a much more usefull 30ft. It is not until you closely examine closely VVA-14 that its vertues become apparent, this ofcourse alluded the ARPA mission to investigate ground effect technology with ease.

[Rotor Rooter]

Then there was the Russian Igor Beaver. He replaced the leading edge weights with magnets on the helicopters that were working around Chernobyl.

This increased their lift by 20%. The magnets forced the heavily ionized air to go below the blades.


http://www.unicopter.com/Chairshot.gif

OK. I lied. But it seemed like a good idea last night. :)

[Luc De Keyser]

How would the MIP do a vertical lift off - deflection of jet flow? Luc

[Ga6riel]

it uses 2 rows of verticaly mounted lift engines in the main hull
(see the access doors at centre on the attached image)
and also uses PAR (Power Augmented Ram)
PAR engines adjacent the cockpit blow air beneath the wing hull and virtually blow the hull off the surface, the combined component is both lift and thrust. In flight more conventional D30 series engines on the upper hull provide thrust

[Ga6riel]

Dave
A craft adequately in ground effect, will pump the Clmax from a usual 1.2 to 1.4 clean to a fraction above 2.0, no flap. Considering AUW 550lb, Cl 1.3, 148 sq ft,
a calculated stall of 49 ft sec (33mph) becomes a stall of 26 ft sec (26.5mph)
you can get more with flaps and boundary layer control.

Why is this a good thing to do?
It 'safely' closes the gap to the tipping point moving stall closer to the zero speed end of the regime.

It adds little weight its just a mode operational and configuration planform issue.

It universally expands the areas of operation from paved or grass strip to anything satisfactorily flat. Be it rock strewn or sand or whatever

Edit to add: VTOL is such a tall order both technicly and practicly you really need to have everything working for you at once. The crude days of blowing something off the deck via thrust alone have come but are passing. Even STOL has proven somewhat prohibitive because the hull insurance costs are not competitive with simpler forms.

[Rotor Rooter]

Ga6riel,

Now you have done it. You've used logic, knowledge and common sense to destroy a plausibly ludicrous idea.

Going off topic for a moment:
If you insist on having some forward velocity, then how about this idea. :D XSTOL & Airpad (http://www.unicopter.com/1366.html)

Staying off topic for another moment.
I lived in Adelaide for about 6 months many, many years ago. When leaving, I stood at the side of the road all day, trying to thumb a ride across the Nullarbor Plains. Finally, I went to the train station a bought a train ticket. What a surprise to see the train with flatdecks, all loaded with semi-trailers and tractors. Even the truckers did not drive across the Nullarbor plains.

Dave

[Ga6riel]

Ga6riel,

Now you have done it. You've used logic, knowledge and common sense to destroy a plausibly ludicrous idea.

Going off topic for a moment:
If you insist on having some forward velocity, then how about this idea. :D XSTOL & Airpad (http://www.unicopter.com/1366.html)

Staying off topic for another moment.
I lived in Adelaide for about 6 months many, many years ago. When leaving, I stood at the side of the road all day, trying to thumb a ride across the Nullarbor Plains. Finally, I went to the train station a bought a train ticket. What a surprise to see the train with flatdecks, all loaded with semi-trailers and tractors. Even the truckers did not drive across the Nullarbor plains.

Dave


Dave
what can I say....its a skill :)

yes its a good (or rather bad) 30 hour drive across to the west, and anyone with any sense should try to avoid it. Actually I am fortunate enough to live in the Adelaide Hills somewhat east of the city.

[gyrodes]

Bloody tipical statement from a crow eater, look at who kicked ya ass's this year:D :D :D :D :D both the Eagles and the Dockers:rolleyes: :D . Have a nice year. Ah I'm not even a football fan.:D :D Des Garvin