Sweet Vertical Jump

[rotorod]

Does anyone know about this sweet set up? This one makes a believer out of me
http://www.youtube.com/watch?v=CFNc1iY8wi0

[danmcgee]

That was done by Carter Copter, from what I understand the engine provides power to the blades and the prop at the same time and both the pitch of the blades and the prop can be changed to create a sharper angle of atack and then return for normal flight.

The one that know the most about this is TimChich.

[rotorod]

That's the way to do it, sounds so efficient. By the way, love the Hornet. I might go to that since the drop keel is a good idea. I have seen some go to the original tail design and pulled it off. Are you still going that way Dan?

[GyroRon]

Originally Posted by danmcgee

That was done by Carter Copter, from what I understand the engine provides power to the blades and the prop at the same time and both the pitch of the blades and the prop can be changed to create a sharper angle of atack and then return for normal flight.

The one that know the most about this is TimChich.

Hey Tim, What else could you tell me about this neat gyro?

[fiveboy]

Originally Posted by danmcgee

That was done by Carter Copter, from what I understand the engine provides power to the blades and the prop at the same time and both the pitch of the blades and the prop can be changed to create a sharper angle of atack and then return for normal flight.

The one that know the most about this is TimChich.

How is that not by definition a helicopter vs a gyro?

[Timchick]

I've never seen it in person so I definately don't know as much as the people who saw it at Mentone. Here's how I understand it:

The rotorblades and prop are variable pitch. Both the rotors and the prop are flattened out during prerotation. The power to the rotorblades is through a prerotator. They are not powered during flight. Once the blades are spun up the pilot disengages the prerotator and initiates the jump sequence which is controlled by some sort of device that increases the rotor pitch for the jump and then reduces the pitch to flight pitch. Somewhere along the way the prop pitch is also increased for normal flight. Rusty Nance was the pilot at Mentone. If you search the forum you can find more info and photos of it.

Carter Copter has no intentions on selling a single place gyro like this. It's just a platform to test their technology they plan to use on their larger gyros. I'd love to have a single place gyro like this.

http://www.cartercopters.com/

Fiveboy, helicopters power the rotorblades during flight, gyros do not.

[danmcgee]

Rotorod I do plan to keep the tail just as it is. We moved it home so I can finish it now. Still hopr to have it in the air this summer. Was a very fun build.

Dan

[Tex~N~Oz]

Hey Tim,
You forgot to mention the HUGE amounts of depleted uranium they use in the wing tips to store that energy. Apparently it made the disk too heavy and so unresponsive that it was sluggish to fly and not much fun as a gyro, though it climbed like a rocket once the collective was pitched.

[Chuck Roberg]

Here's the video I took during Oshkosh 2007. This was at Fond Du Lac Airport where Rusty was getting a little practice in before demoing it at Oshkosh.

The first jump take off Rusty actually had a ground roll of about 10-12 feet. Rusty later told us since he hadn't flown it for a while he wanted to take it easy the first time. His second try is what you see in the video.

From what I know. Timchick is correct in his explanation of the jump take off sequence. When the rotor is pitched so is the propeller. From my vague memory I believe it is one lever or switch that accomplishes both operations. When the rotor is up to speed flip the switch and hold on. And yes there is weights in the rotor tips.

Amazingly this is all accomplished with a Rotax 582 engine.

I was doing demo flights at Fond Du Lac so I was not able to see the actual jump demonstration at Oshkosh. But luckily I was not flying during the time of his jump take off at Fond Du Lac.


http://au.youtube.com/watch?v=KpvIgfwF9hU

[Passin' Thru]

Here's another video of same machine doing several different takeoffs and landings.
http://www.youtube.com/watch?v=Q3qPV...eature=related

[Vance]

What happened to the two place production one coming in 2008?

Thank you, Vance

[GyroCFI]

From these videos, it appears that there's some kind of extension at the trailing edge of the rotor blade near the tip. Is that a controlable surface, or a some kind of trim tab?

[Hognose]

I did see this ship (CGD/T) fly at Osh a couple years ago and both attended the presser and hung out at the CC tent a bit. As stated, this is strictly a technology demonstrator and development aircraft.

The original CCTD was a great idea. But:

• a bad choice of powerplant (actually several serial bad choices, unsorted auto conversions);
• the usual development teething;
• Jay Carter's extremely fertile mind and able collaborators, and the constant changes and improvements this produced;
• post-crash rebuilds (see "development teething"); and...
• trying to revolutionize airframe, rotor and propeller all at once...

...meant that having only a single machine, and doing all R&D on the one tech demonstrator, meant lots of downtime and very slow-moving development. So Jay wanted a simpler demonstrator airframe and one of Larry Neal's Butterflys was selected. It got Carter rotors and prop, which have a unique kind of skeleton-driven pitch-change mechanism (that works like your radius and ulna in your forearm), and a sort of push-button jump takeoff mechanism which, as I understand it, auto-sequences the takeoff transition from power to the rotor to power to the prop.

In answer to some of the specific questions:

[Vance] I presume that any kit production is delayed by the financial tsunami we've all been through. Their website shows that production of the 2+2 prototype continues, and they're taking deposits on kits of that specific aircraft at this time. From Carter I've come to expect eye-popping genius, not schedule discipline.

[Don] The tips are not a movable surface, they're part of Carter's patented rotor design and seem to have some of the properties of BERP tips. They also do hold the tip weights. That said, the rotor is often subject to change or replacement. Here's the mold for the 2+2 PAV rotor:
http://www.cartercopters.com/images/...blade_skin.jpg

[Tex-n-Oz] There are DU tip weights but I dunno how that affects handling, compared to the rotor's higher aspect ratio vis-a-vis common state-of-the-art rotors like Dragon Wings, Sport Rotors, or for the guys down under, Patroneys. (Meaning, the Carter rotor has less chord and more span. I am not sure what the MAC of the rotor is but I believe that this rotor spans 26').

Rusty sometimes posts here. I don't know if anyone but George Mitchell and Rusty has flown this machine.

[Rob Fiveson] The reason this is not a helicopter (nor are other jump gyros like the A&S 18 or Dick DeGraw's partially-powered-rotor machines), is that while it can jump take-off it can't use its collective pitch to hover. It also can't fly in non-forward translation, unlike a helicopter. Dick's machines can use their collective on landing -- I'm not sure the CGT/D can do that in its current iteration. Of course, most civil helicopter uses DO need VTOL but DON'T need hover. (Powerline maintenance, search and rescue, logging and firefighting might be the only exceptions).

Photos and video here:

http://www.cartercopters.com/ctd-t.html

Now, these answers are not official in any way -- I have no connection to the program, except admiration and having previously used my now-forsaken media status to pump them for information.

cheers

-=K=-

[fiveboy]

Dear Tim

Yes of course I know a helo has a powered rotor (I read the same books you do!). What I meant was that based on what Dan wrote

from what I understand the engine provides power to the blades and the prop at the same time and both the pitch of the blades and the prop can be changed to create a sharper angle of atack and then return for normal flight.

It sounded like the power was on the blades during liftoff. That combined with the variable everything made it sound like for that period of jump, it was a helo.

Mr. Nose thanks for the clarification. I see now that once the power is let go of on the jump, its a gyro (albeit one with a variable pitch rotor).

So is it a helo for those few moments leading into jump? Powered rotor, variable pitch. Im guessing maybe if they stayed engaged and played with the pitch they could perhaps even hover?????

[Timchick]

Fiveboy,
There is no collective to adjust the rotor pitch during flight. The controller adjusts the pitch of the rotors during the jump takeoff sequence and after that if flies in a fixed pitch state. If the rotor stayed engaged during flight it would need a tail rotor.