Tractor gyro landing gear

[cluttonfred]

The vast majority of tractor gyros are taildraggers, while a few modern examples have tricycle gear. Most tractor gyros date from a time when most fixed-wing aircraft were taildraggers, but then again there are a number of modern helicopters that use a taildragger arrangement as well. Are there any particular pros or cons to taildragger vs. tricycle gear for a tractor gyro?

 

[Steve_UK]

Gyrocopters are a small niche within general aviation. Tractor gyros are a tiny sub niche within this. Question how many tractor gyros are currently airworthy on planet earth today. I've no idea but would guess at 25 maybe less.

 

[cluttonfred]

And that answers the question how...? ;-). My point is that there was a time when there were hundreds of general aviation gyros flying, almost all of them tractor taildraggers. Is there any reason why taildragger gear is better for a tractor configuration gyro or is it just a historical artifact?

 

[Steve_UK]

""And that answers the question how...? ;""

Today they are not common, they rare. Their hay day was pre WW2.
Tail wheel aircraft of all types were the norm.

"The vast majority of tractor gyros are taildraggers,...."

Can you quantify this - how many - approx - do you think they are common and manyfold?


Tractor gyro developement has been even sleepier than gyro development.

The designs we know are nostalgia timewarp designs from yesteryear.

Meanwhile back in 2016 Phenix are trying to bring a Nose Wheel tractor gyro to market - long slow process but they are moving forward with German certificate in progress.

Bulldog also have a new modern tractor gyro which is a taildragger - prototype yet to fly.......

The modern gyro market is small - how big will the modern Nose Wheel Tractor gyro slice of this small market be - I hope Phenix do well but it's going be hard to be viable.

 

[cluttonfred]

Thanks, Steve, all valid points. That the vast majority of tractor gyros, and I mean all tractor gyros ever made, are taildraggers is a given as the tractor configuration was by far the most common until the 1950s and almost all of those had taildragger gear.

As you said, when we think of tractor gyros we mostly think of antiques, but I am not looking to build a replica, I am trying to understand the design issues involved. I am not too concerned about market as I am not planning a business, just exploring what interests me personally.

That said, I do think that some folks, especially fixed-wing pilots used to flying tractor designs, would be attracted to an affordable and relatively easy to build one- or two-seat tractor gyro. If so, great, if not, no worries.

 

[rickloon]

I am NOT a gyro designer , but it may be easyer to pre-rotate for take off and flare for landing with a tail dragger set up as the aoa of the disc can be more rearward with out hitting the tail.
Rick

 

[WaspAir]

From a slightly different perspective, taildragger ("conventional") gear on airplanes was wonderful for rough surfaces, but added challenges for the pilot on landing because of the speed involved, with risk of ground-looping, loss of directional control and so forth, and is uncommon today in airplanes for that reason. Gyros don't ever need to move as fast on the ground as an airplane; they can land with very, very, little speed, and the issues that bedevil airplanes don't loom so large. Managing a taildragger is not such a big deal if you don't exceed taxi speeds, and gyro landings should be done at no more than taxi speeds.

 

[phantom]

Here is the main reason I don't like taildragger gyros, the rotor with the stick forward is zero degrees so it will stop in any wind condition, with the stick full back the rotor is about twenty degrees and with a stick set up normally this range is about as far as you can reach, if a machine sits at ten degrees nose up on the ground you would need to get the extra travel at the head by making the stick more sensitive or find room to make more travel at the stick, on wheels you can live with this because if you land dead stick the wind will move it backward and with a peddle pushed you can get it side to the wind and stop the rotor , on skis in snow the tail ski will dig in and there will be no way to stop the rotor, if there is enough wind it would flip over backward.
Norm

 

[PW_Plack]

My point is that there was a time when there were hundreds of general aviation gyros flying, almost all of them tractor taildraggers. Is there any reason why taildragger gear is better for a tractor configuration gyro or is it just a historical artifact?

I doubt there were even a hundred flying at their historical peak, but I could be misinformed.

One reason the pushers are so much more common in small gyros is because the moment of inertia is much smaller. With the pilot and the engine as the two main masses, a tractor spreads them out farther apart, while a pusher has them both quite close to the mast. If you watch a tractor gyro in flight, it is much more serene and experience. Pusher gyros are better for the "yank-&-bank" crowd.

For the same reason, the tractor is harder to get into trouble by accident.

The point made above about the rotor's range of movement in pitch is significant. Getting the rotor stopped using forward stick, or even to have the capability to arrest destructive flapping if needed, would require care in design.

 

[cluttonfred]

Thanks, guys. IIUC, Norm's point is that the nose-up attitude of a taildragger gyro at rest is more susceptible to issues on the ground in high winds? Was that a problem historically and would it be solved with a rotor brake for ground use?

One possible compromise might be reverse tricycle gear in which the tailwheel is actually closer to mid-fuselage and the fuselage therefore sits in a much more level attitude.

I suppose the other part of the question is whether or not taildragger gear avoids or reduces any issues with tricycle gear for a tractor gyro in terms of nosing over, damaging the nosewheel strut, etc.

I do believe that when you add up all the Cierva-companies around the world plus other manufactures you would get up to hundreds of gyros flying in the 1930s but that's just a guess.

About the more stable and serene nature of tractor gryo flying, well, personally that sounds great to me. Different strokes.... ;-)

 

[cluttonfred]

Here is an earlier thread with some examples of tractor gyros with tricycle gear.

http://www.rotaryforum.com/forum/showpost.php?p=283429&postcount=7

 

[Richard Anderson]

According to what I've read, Arliss Riggs built both types and greatly preferred the tricycle gear type.

 

[cluttonfred]

Thanks, I looked up and read the old PRA Arliss Riggs articles posted in this forum, sounds like someone I would have liked to meet!

It does occur to me that the ideal tractor gyro tricycle gear might have a more nose-up stance on the ground than for a pusher in order to allow some shock-absorbing distance in a steep, short landing without pranging the prop.

 

[Richard Anderson]

Again, based on what I've read, the placement of the main gear on a taildragger gyro is critical to prevent nosing over/prop strikes when the rotor is leveled after landing. Unfortunately, just holding the rotor back until it slows down can result in the gyro rolling backwards- not fun in a taildragger. Additionally, gyros of the "Golden Age" had the advantage of operating from grass airfields so they could always takeoff and land directly into the wind.

 

[cluttonfred]

Thanks, Richard, that complements what Norm (phantom) said earlier about a ground stance that is too nose high making it difficult to level the rotor to stop it in the wind. So that makes two key considerations, both being able to level the rotor on the ground and avoiding a nose-over in the process. It sounds like the ground stance should be similar whether tricycle or taildragger. It also makes we wonder about the typical high angle landing that gyros make when trying to land in a short distance. While that last point might seem to favor tricycle gear, I think a tractor gyro would require especially rugged and heavy nose gear to avoid prop strike in extreme landings. The reverse tricycle arrangement, perhaps with that third wheel just a big as the mains and with plenty of shock-absorbing travel, might work well.

 

[GSobo]

I'm late to this conversation, but I'll add the response I've read from Ron Herron, the designer of the Little Wing gyro. Ron points out that a major advantage of a tractor gyro is the opportunity to install a larger diameter propeller than can be used on a pusher gyro. A pusher configuration is seriously limited in propeller diameter, due to center of thrust being sandwiched between the rotor and the ground, not to mention tail attachment points.

The larger diameter prop will offer quieter ride and superior performance. If you put tricycle gear on a tractor gyro, you've lost that asset.

I also notice that people interested in tractor gyros seem to like the resemblance to historical autogyros and STOL aircraft like the Piper Cub, so that market force may also be in play.