Why Are No MFRs retrofitting Jump Start

Taken from the WTF thread

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BEN S BEN S is offline
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Join Date: Nov 2007
Location: YUMA,AZ
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Default People keep trying to re-invent something we already have made!
the perfect PAV is no/low emissions, cheap to buy and operate, easy to learn how to control,has the ability to decend safely without power,can take off from a driveway and land on one as well and has decent range.
How about an electric hybrid gyroplane with a good jump takeoff? I NEVER understood why manufacturers didn't attempt to come out with a simple retro fit kit for gyros to do jump take-offs. Seriously NASA, couldn't you find something a little more useful to waste our money on?
Ben S

I totally agree with Ben and his retro fit idea.

Carter set up a modified single seater to do just that, and now won't sell it; or even plans for it.
Its a damned shame. Thing demo'ed like a champ.

Yup sucked me into gyros with that thing though I can't grumble about that.

I believe that the drawback was that it then had seriously compromised agility.

The old saying is can't get something for nothing, you always pay for it somewhere.

Old saying is if you don't see it on an aircraft think two things. Cost. Weight.

All the jump schemes I've seen require controllable collective pitch (flat pitch to spin up, add pitch to jump). That would be a major modification to the typical simple teetering rotor system with fixed collective pitch that most gyros use, and not a simple retro-fit.

I am no expert but Wiley Coyote had these big springs...look it up.

WaspAir said:

All the jump schemes I've seen require controllable collective pitch (flat pitch to spin up, add pitch to jump). That would be a major modification to the typical simple teetering rotor system with fixed collective pitch that most gyros use, and not a simple retro-fit.

Click to expand...

This was a simple bolt-on conversion that would fit any Air Command head that I built back in the late 1980's. Worked very well, just pull down on the handle on the front of the rotor-head, which cocked the blades into a flat pitch, then after you spin it up, pull a trigger and POW!!, up you go.

The problem with the system was going with hydraulic power, which is too inefficient and heavy. If I were to do it again, I would use mechanical power.

The problem is not the technology, the problem is the training, or lack of, and thats why I never moved forward with it again... yet.

http://www.youtube.com/watch?v=e2AnpuX866Q

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I'm having trouble with the video (local network issues).

Did you have feathering hinges in the head?

WaspAir said:

I'm having trouble with the video (local network issues).

Did you have feathering hinges in the head?

Click to expand...

No, just pitch.

Dennis

That looks like a pretty good idea. Why didn't you run with it?

frankjhelms said:

Carter set up a modified single seater to do just that, and now won't sell it; or even plans for it.
Its a damned shame. Thing demo'ed like a champ.

Click to expand...

Carter is a technology development company which then licenses it's inventions to other companies, if no business has decided to manufacture their jump mechanism it's probably because there is not enough of a market to make it a profitable venture.

The other issue, especially here in the U.S., is that it's unlikely that any gyro with jump capability would be a true ultralight and since the Sport Pilot regs specifically prohibit a gyro with feathering hinges it would require a proper pilots license to fly such a machine.
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edypaul said:

Dennis

That looks like a pretty good idea. Why didn't you run with it?

Click to expand...

Some procurement company made me an offer I couldn't refuse for the only prototype aircraft and all the rights, including all pictures and videos of it flying, and had me sign a contact good for 10 years not to disclose information about it or to develop another during the time of that contract. After the contract was up, I had sold Air Command and was deep into helicopter development and manufacturing, and had no need to pursue it.

For those that want to know more about what Carter Aviation has done, are doing, or plan to do in the future, Jay Carter will be doing a presentation on the Internet on the Utah Rotorcraft Association's Webinar coming up on the 13th of this month. After his presentation attendees will be able to ask him questions so you can hear it from the man himself. For more details on how to log on a be a part of this Free Webinar, go to "utahrotorcraft.org".

That said, there is obviously more to making a Gyro Jump capable or everyone would be doing it. I know I have talked to Larry Neal about it and he said he could but he doesn't want to. He feels the cost and downsides that come with that capability are too high and instead has chosen to pursue very short takeoff capability. With a powerful pre-rotator and the right set up there is no reason why a Gyro can't take off in less than 100 feet and that is without the downsides that come with the jump capability. Everything in life comes with trade offs and before you can make a good decision about what you want, you need to know what it will cost you so you can decide if it is worth it.

The dream of an inexpensive, simple bolt on upgrade, that will make any Gyro jump capable, is just that, a dream. The issue is more complicated that that and when someone does come out with it, you can bet it is going to cost some money and they will want to be paid for what they have developed, not just donate it to all the Gyro enthusiasts in the world.

Reasons jump kits are not available:

(1) Once committed, no way to abort safely.
(2) Guaranteed to be in the height-velocity danger area on every launch.
(3) Need for a reliable, durable way to get power to the rotor.
(4) Cost, weight, complexity.

And the biggie...

(5) Lots of dreamers, few actual buyers!

Too bad a device like this couldn't fall under the "ground-adjustable prop" rule. That would allow sport pilots to use jumpers, and would vastly expand the potential market.

Well guys since it was my origional post ...

Well guys since it was my origional post ...

That started this thread, it was not meant as idle daydreaming but more of a cost benefit analysis of the ridiculous money NASA would be prepared to waste on an essentially useless program.
Having said that, I believe the future of light gyro planes could get a huge boost in sales if you could take off from your backyard and land there as well.
The complexity of a helicopter is directly related to the ability and desire to hover. Vertical take off and landings were solved a long time ago during the cierva/pitcairn days as evidenced by the cool videos you can watch on youtube.
What is the answer? I was under the impression that in order to jump you needed to be able pre-rotate to 150 %of the cruise speed. Although this might seem like a difficult task imagine a small spun cylinder that contains compressed air and fed to tip jets as a prerotator booster. heck somebody could even come up with an in air compressor to re-jam the tank while flying. As for the pitch control, just sell the whole kit and caboodle ...the rotors, rotor head and tip jets as one unit for a certain size gyro.
As for being in the Height velocity curve, you are of course right, but with the rotors up to speed you would have way more than enough retained energy to settle back down safely if something was not right.
Heck since I'm on the roll here, how about a ring of staggered rare earth magnets that have thair polarities reversed on a central ring on the mast to repel a matching ring on the botom of the rotors to increase efficiency of the rotors spinning. Some of you will probably just start spewing that ridiculous alphabet math to show me why these things won't work, but thats the same math NASA was using to prove the need for their little puffin idea to congress!
I gots lotsa ideas like these, but in the end, I'm pretty content with my sportcopter and don't have to much ability to conjure up these things which would just eat up my flying time.
As for the Carter team I can't say because I'm just a simple guy, but if they have an idea good enough to work and build it and test it, why in hell would anyone in the company think its a good idea to just sell off the rights to these ideas? That is stone cold government thinking in my book, and I oughta know, worked in military testing for years and you could see it..pencil protected slide ruled jerk-offs whose main thrust in testing new weapons systems WASN'T providing our soldiers with the latest and greatest weapons systems, it was to get to the next level of Gov't dole out grant money to just keep it going. That WAS their job. And let me tell you some of those guys were PRO's! (can anyone say crusader? hell we used to call it the EOD kids college fund!)
Sorry...where was I..oh yeah so are jumps necessary? I say hell yes if you want to appeal to the masses. With some new developments in hybrid engine efficiency (and my magnet idea) you could probably make it an electric hybrid in 10 years, and I don't think we need NASA to cook it up for us we need ourselves the hobbyist to invent it. When I used to train spec-ops guys I would always tell them if you want to learn how to do something right, don't go to the government sponsored instructor, seek out the dude who is paying his OWN hard earned money to do it, he will be up on all the latest gear. Look at mixed gas diving for instance Yeah NavDivSalTraCen in Panama City is the mecca for that kind of training, but go outside the fence and that guy who LIVES to make his next nitrox dive can probably tell you exactly why your mix is wrong.
Dang it see you got me rambling again. Sorry
I'm done:yo:
Ben S

I am absolutely for jump start ability on a gyro.

This is something that would really make it a useful machine, able to
operate out of helipads.

The problem is certification and training.

Although Osprey made a breakthrough for "transitional" aircraft,
it probably will take a lot of time. before you can include any jump start
to any existing LSA or experimental category.

PTKay said:

I am absolutely for jump start ability on a gyro.

This is something that would really make it a useful machine, able to
operate out of helipads.

The problem is certification and training.

Although Osprey made a breakthrough for "transitional" aircraft,
it probably will take a lot of time. before you can include any jump start
to any existing LSA or experimental category.

Click to expand...

If people will remember. Gyroplanes almost got left out of Sport Pilot because it was thought they were too complex by the FAA.

Adding jump capability to a Gyroplane would almost certainly take it out of the Light Sport category. This would limit it's market value to those pilots only holding a Sport Pilot Gyroplane rating.

Gyroplane's are already a rather small market. I'm not sure if a U.S. manufacture would be willing to spend money on designing, testing and marketing something that would have an even smaller market potential.

I would really like to see a Gyroplane with jump capabilities. I think the first one for sale will come from the European market. When it does I see a lot of Sport Pilots going for their Private rating.

Jump takeoff has already been done by several different people or groups. It's not that we don't have the technology or that it can't be done. The problems are: It is more complex, It is more expensive, It takes greater flying skill and takes us further away from being safe and simple flying machines and there is not enough of a market to get the big guys (who are only interested in business projects that have a high probability of being financially profitable) interested in pursuing it.

So for now it is up to us to do it our self and several people that really wanted it and were willing to pay the price to develop it, have done just that. Just don't look for it to be a simple, inexpensive, bolt on upgrade to your current machine that won't take much effort on your part. Any change to the design of a flying machine can have dramatic changes to how it flies or how stable it is. So if you are going to make these kind of changes you need to be ready to compensate for the changes you make and make sure the complete package is safe to fly. I believe those that choose to take this journey will learn a lot, and be greatly rewarded for their efforts and that is what the experimental category was designed for, but be prepared for a long journey as it won't turn out to be a Sunday afternoon stroll.

BEN S said:

I believe the future of light gyro planes could get a huge boost in sales if you could take off from your backyard and land there as well.

Click to expand...

The problem with taking off in your back yard for most of us, isn't aircraft's ability its zoning and neighbors.

I live on a bona fide FAA designated airstrip and we have a neighbor who calls the county regularly because, in her opinion there it too many airplanes. Yeah shocking, airplanes at an airport, whoda thunk it.

PW_Plack said:

Reasons jump kits are not available:
(1) Once committed, no way to abort safely.
(2) Guaranteed to be in the height-velocity danger area on every launch.
(3) Need for a reliable, durable way to get power to the rotor.
(4) Cost, weight, complexity.

Click to expand...

PTKay said:

The problem is certification and training.

Click to expand...

I do jump take-offs all the time in the A&S 18A (o.k., I'll admit that often I roll eight or ten feet before I jump off, but I don't think that little difference really matters here).

The extra training needed is trivial compared to all the effort people put into rotor management, and would save many, many hours in net. You must be trained to do a jump, but it's not terribly difficult to do. It only adds an hour or two to the training syllabus, but more importantly, having a 150% pre-spin capability eliminates the enormous amount of time people spend running up and down the runway balancing on the mains, trying crow hops, and worrying about rotor rpm vs. forward speed. When you start out with 150% of flight rpm before you've rolled an inch, none of that is necessary.

Aborted jumps have always been a normal part of the training. With all the extra energy stored in the rotor system, it isn't the big h-v problem you might think. Consider also that the moment you release the clutch, you've got full thrust available to gain forward airspeed as you climb and as rpm decays down to 100%.

Reliable drive isn't that hard to engineer - A&S did it in 1965 with a belt drive from the engine, a multi-plate clutch, and a simple transmission.

Cost and weight are valid concerns. Besides the drive system, you need feathering hinges so that you can get flat collective pitch for spin up while allowing rapid shift to flight pitch for take-off.

Heavy blades also help to store enough energy. My J-2 would do a half-baked jump if I was lightly loaded and had a bit of wind, but with a light rotor system and only 125% pre-spin, there wasn't enough energy stored to lift the whole ship routinely. Spinning big ones really fast will do the trick.

I got my Gyro add on rating in the A/S 18A. Hitting that jump switch is like being pulled heavenward by a long stretchy rubber band. Like no other experience, a different feel from a helicopter vertical assent .

And while we are discussing gyro's with jump, let's not forget those demonstrated by Dick DeGraw at the PRA national convention.

Video Link > http://www.youtube.com/watch?v=9gfBYARn-T8

Karols new Jumpin Gyro > http://www.youtube.com/watch?v=9ISIlgMcb-U