Helicopter Design - Idea Discussion

[Dennis15221]

As Eric Hunt pointed out above, if you have sufficient fixed angle of attack to generate lift, then an engine failure will result in a rapid decay of rotor RPM. Free-wheeling clutches will let the blades continue to turn, but drag will slow them down until they stall. The helicopter will fall from the sky like a brick.

 

And if the angle of attack is minimal enough to somehow maintain sufficient RRPM for a "controlled descent," you still lack the means to steer during descent or cushion the landing.

 

I can't think of a way that a fixed-pitch helicopter can survive an engine failure at altitude.

Thank you for this input. I will spend some time studying this issue. I will either find a way to effectively deal with it or may scrap this design idea.

[WolftalonID]

Dennis...as an engineer, how much of it has been in aeronautical fields? It is an important part of why we fly the way we do, and this area of expertise has some of the worlds brightest minds working to change the way we fly everyday. I would sugest taking the time to at least invest in a private pilot ground for helicopters and get to know them more intimatly. Then maybe your concepts will have roots from which to grow vs ignoring basic concepts of earths atmosphere and how flight within it is achieved.

 

Flight contols, AI integration, etc comes second. I am sure your idea is good, as many peoples have been in this field, bu some of the ideas you have posted seem to show ignorance towards aviation. Part of what we are taught in flight school is why the machines do fly, and what can make them stop flying and how to avoid that happening.

[Dennis15221]

WolftalonID,

Since I am not a pilot or aeronautical engineer, my information is limited on this subject matter. I do understand some of the subject matter. I got into this forum to learn some things and to discuss some design ideas. If any of my ideas sound stupid, I want to know why. I do not want to build a vehicle that is not considered safe. Please note that most vehicles(by air, water or land) still have accidents, mechanical malfunctions and pilot/driver errors. Even the vehicles that are considered to be very safe, still crash.

 

After looking into the Auto-Rotation issue, I discovered that my intended design will not allow for a safe landing when power is removed. Now I understand why the throttle and collective are separate controls.

 

I would like to go through helicopter flight school, but lack the funds for it. So for now, I am happy to discuss some of these issue with the experts.

[WolftalonID]

The discusions here can be helpful for sure, however, not always informative. There are several here that can be very informative, and knowledgable. I am a CFI, but lack engineering or A&P experience. Several guys here do have that to help with.

 

I mentioned a ground class as they are less expensive, but very informative. Your engeneer mind would/should grasp a deeper understanding of the material, especially the science part of it all.

 

Who knows....the ground class could be a step towards further flight too!

 

If a formal class is out of the question, grab a few of the books used and do a home study approach.

[aeroscout]

Any dream worth having, is worth pursuing. Keep after it Dennis.

[Dennis15221]

Is the "Auto-Rotation" ability a mandatory requirement by FAA? Does the Osprey have the "Auto-Rotation" ability?

[Nearly Retired]

Osprey...autorotate? Well...yes and no. But first we must understand that the V-22 Osprey is not yet certified by the FAA. So it need not be able to autorotate in a conventional sense (meaning that it cannot flare to a zero ground-run landing).

 

However with the rotors in helicopter mode, the V-22 can indeed autorotate although the rate of descent is quite high and it *will* be a fast run-on landing at the bottom and probably a pretty solid vertical hit unless the timing of the flare is exquisite. Preferable would be to "glide" down in airplane mode and take advantage of the sacrificial proprotors upon landing - theoretically they'll absorb and dissipate some of the energy. And it's all theoretical because no V-22 has yet had to land with zero power. Hopefully that'll never happen.

 

The V-22's lack of genuine autorotative capability is a sore-point for some. Me, I just look at the instances of complete power failure in multi-engine aircraft - for me it's not an issue. It does happen, admittedly, but rarely.

[Wally]

Is the "Auto-Rotation" ability a mandatory requirement by FAA? Does the Osprey have the "Auto-Rotation" ability?

 

Yes, autorotative capability is mandatory for helicopters.

Fighters have ejections seats, Cirrus has a whole-aircraft parachute, but they can still glide, and that's all an autorotation is.

Engine failures occur so infrequently that brief exposures in scenarios where a power failure would be an issue can be a profitable assumption of calculated risk, but hanging by an engine or two for the whole flight would be acceptable to very few rational people.

There are long lists of issues where a power chop is the first step to survival, most eliminated by the proposed inability to glide (autorotate). I would not hover, much less fly in a helo that wouldn't autorotate.