Fiberglass rod gear legs?

[choppergabor]

Originally Posted by Vance

Hello Gabor,

It is my understanding that the tire scrub system of dampening the energy doesn’t work well on wet grass or other slippery surfaces.

Most of us don’t land or take off on slippery surfaces so it may not be an important consideration.

Thank you, Vance

Hello Vance my friend. You are absolutely correct about that. The less friction between the tire and the landing surface, the less effectiveness of this simple system.

[Penguin]

Originally Posted by choppergabor

Larry you could not be more incorrect! As the landing gear stretches out due to its spring like nature the energy is being absorbed by the rubbing and dragging of the tires on the surface. It is not the most elegant way but very effective!!! Lots of airplanes use the same system very successfully. There is no such thing as coming back off the ground I have never seen a gyro do that, which had composite landing gear. I have seen rigid axles bounce as you had described though! So yes there is the built in damper by the outward motion of the tires.

Oops! My bad, Gab. Sorry I touched a nerve.
Based on your advise, I am removing the dampers from my 911 this weekend.
Relying on tire scrub, I'm gonna whip up on those boys at the track next weekend!

Coincidentally, another thread points to some thoughts by C. Beaty, in which he summarizes ... "A gyro ought to have a static deflection of ~4 inches which provides a ride rate of ~94 CPM; neither too harsh nor too mushy. Proper damping is a must." He further said "Springs by themselves are only a half measure; they need to be used in conjunction with hydraulic dampers to be fully effective. Otherwise, recoil (rebound) rears its ugly head." (emphasis added.)

http://www.rotaryforum.com/forum/new...reply&p=448676

OTOH, Mike (MissFit) corrects me that the Dom air shocks DO indeed have damping effect. One learns something most every day on this forum, which is why we like it.

[choppergabor]

Originally Posted by Penguin

Oops! My bad, Gab. Sorry I touched a nerve.
Based on your advise, I am removing the dampers from my 911 this weekend.
Relying on tire scrub, I'm gonna whip up on those boys at the track next weekend!

Now Larry Larry Larry.... I did not want to start a war here honestly and it is not about touching a nerve at all. It is simply about understanding the forces of gyrocopter during landing. I would not even be able to get into the same state let alone the same building with Mr.Beaty if the admission depended on smarts and knowledge. So please understand that this theory comes from a guy who speculates a lot and analyzes everything to the point where it becomes disgusting to some . Hard landing on a single spring loaded gyrocopter has the built in damper factor having the blades flap down at the very bottom of the bending action of the landing springs. The flap down action starts out delayed due to inertia and lasts longer for the blades to fully flap down than the landing springs. Therefore on the way up as the landing springs return to the original position you still have the downward force from your blades and that is right there your harmonic damper Voila! I might be wrong about a lot of other things but I do know that all the ELAs, MTOs, Magnis that have the single composite NO SHOCK system I YET have to hear a complaint about bouncing back into the air after a rough landing. Kai? Would you mind to chime in on this? Thank you. So take this with a grain of salt Larry since I know nuttin' and claim nuttin' mo than speculating. Airplanes bounce back because they don't have the flapping damper like gyros having the blade's inertia helping us during hard landing. DISCLAIMER: This is strictly my own speculation and it has no scientific value!

[Penguin]

Not every disagreement in approach need be a war, my friend.
Mike is as adamant that a rigid axle is sufficient as you are that a sprung mass is enough.
I'd be afraid to use anything without real suspension damping.
Yet each works in practice, some better than others in specific circumstances.
There will be advocates of each approach, each with a religious zeal.
My point is simply to think about the inherent advantages and disadvantages of each.

BTW, the 911 bounced out of the parking lot and into a ditch so no damping didn't work out for me. I'm going to try putting a rigid suspension on it next to satisfy Mike ...

[RotoPlane]

I claim the same DISCLAIMER as Gabi….and I have not tried this gear yet.

I have chosen a different way for my main gear because I don't like to use tire scuffing for dampening.
The S2 fiberglass spring is a ½" X 3" bar that is laid up on a mold to give it the radius shown in the No-Load section.
The dampener is a motorcycle type rear shock with adjustable spring rate.
The wheel assembly has a pivot bearing near the axle to allow angled one gear landings and plant both wheels to the ground, sharing the gear load.

[choppergabor]

LOL Larry that is because Lee had Mike under his spell! It all originates from Lee I just know it! Hahahaaaaaaaaaaaaaaaa. But you are right. They all work one way or another they all have their advantages and disadvantages. Some goes for weight some for simplicity and some will follow what Lee says ROFL Sorry Mike Love ya like a brotha. And you know Lee had a good point when he told Mike if he was not going to use the Missfit off road he should be saving weight and not bother with suspension. And it works just fine for him so Lee wasmore than right about it! We on the other hand have no choice. We are wussies and like the feeling of granny's Buick. At least I do! I'll let ya test mine though if I ever get the friggin thing finished......ok ok I am working on it I am on beer break right now ok? Going back right now....sheeeeshhhh
Ed your solution is just way elegant and out of my league. I am not even near that level of thinking! But I am a good lurker I'll be interested to see how it works though. Nothing beats the feeling of a new "working" solution

[scottessex]

Wow! Lots of good concepts! I am just kicking around some ideas, I have flown both rigid and 2 different types of suspended gear off my strip, and a gyro with suspension actually gets off the ground quicker, and it much easier on the rotor head and blades.
Keep the ideas coming!

[WHY]

The main problem with fiberglass rod main gear is "THEY FLEX FORWARD AND BACKWARD AS WELL AS UP AND DOWN", now that can make a rolling take off or landing very interesting if you happen to hit a clump of dirt on a grass strip or a heavy seam or crack in asphalt.

Tony

[scottessex]

Brent I found some pictures of your machine, do you have a drag cable on the gear?

[choppergabor]

Originally Posted by WHY

The main problem with fiberglass rod main gear is "THEY FLEX FORWARD AND BACKWARD AS WELL AS UP AND DOWN", now that can make a rolling take off or landing very interesting if you happen to hit a clump of dirt on a grass strip or a heavy seam or crack in asphalt.

Tony

Not mine! I do have a drag link attached and should make things a bit more controlled.

[WHY]

Hi Chop

Your right, you will have none of the yaw flexing on your gear, it's not a rod design. When a rod flexes front to back, for a very brief moment that wheel is out of track alignment and can set up some funny motions.

Tony

[Brent_Brown]

No and I fly off grass with holes and have no trouble. Thank for the photo of the two place. most of the parts from the two place are on that 670 moster with one seat.

[gyroplanes]

The Honeybee fiberglass rods on my friend's gyro were way too long and caused toe angle changes with every bump. Worst ground handling gyro I ever saw. Shortening the rods made it useable.

[GyroRon]

Originally Posted by Brent_Brown

No and I fly off grass with holes and have no trouble. Thank for the photo of the two place. most of the parts from the two place are on that 670 moster with one seat.

I see my old RF150 parked besides Brents monster gyro..... Sold that gyro to Chuck Irby, and he rolled it over trying to learn to fly it.

I never really liked the fiberglass rod gear legs, the ones I have used felt too flexible if there is such a thing. They do work though. I think my Titan plane has em. I am a much bigger fan of spring aluminum gear such as grove gear. They are more expensive than fiberglass, but I like the way they ride and I feel they are very strong and worry free. Carl S. makes his own aluminum gear out of plain aluminum flat stock. Not too expensive that way

[StanFoster]

Gabors fiberglass landing gear is very solid and securely mounted. It wont be like the fiberglass shovel handles I have seen. They have a nice feel to them.

Stan