BillHarris

Years ago, Ernst marketed an aiplane restrainer that consisted of a flat plate staked to the ground with retractable to bear against the stab. Much the same device as the J and L Products "Tail Trap" http://jlproducts.net/ .

This Tail Trap looks well-designed and the cost is not to bad, but in the spirit of aeromodeling I wonder if I ought not to build a plane restrainer. I have a design floating aroubd in my head, based on the J&L and the Ernst devices.

With my 40-60 size planes I'm using a piece of 3/4" nylon webbing clipped to a 12" landscape spike hammered into the ground and looped around the tailfeathers, but I'd like something fancier...

Mustang Man-RCU

Bill, We have a fellow who builds the set up I think you have in mind. It is for restraining your plane on the ground and consists of a spike that goes into the ground and when you pull the plane back 10" or so the upright restraints fall back to release the stab. The price is reasonable and if you are interested in one e-mail me and I'll put you in touch with him.
Steve

beepee

Bill,

I have got one of my own design, very simple and cheap. It is constructed of 3/4" PVC pipe and made in a "U" pattern with a T fitting at the bottom center of the U. The T is threaded for 3/4" pipe in the center. In that is a 1/8" x 3/4" bushing with a 1/8" nipple about 6" long. In that nipple is a 3/16" steel rod spike. The PVC pipe is covered in insulation. Harder to describe than to build. It is fixed though (does not lay down), but is lay down really necessary? I think you would be hard pressed to spend $5 on the parts to build it.

Bedford

BillHarris

I've seen (and have considered making) one of those "U" restrainers, but I've been interested in making a lay-down style restrainer.

For a larger scale bird, it is more convenient to run the engine up and the quickly release the plane to fly.

Just looking for a different do-dad, I guess...

crossed thumbs-delete

Bill check this web site. They have a good one. Look under specials. Will ship to you.
www.flyingzhobbies.com

rcpilot44

My Feedback: (1)

Here is one that Midwest makes, check out link from Tower Hobby.
Has anyone used one of these on a 1/4 scale plane? I am not sure if I would trust one of these to hold back my plane.

http://www2.towerhobbies.com/cgi-bin...?&I=LXAR03&P=0

crossed thumbs-delete

RCPILOT44

I have a 1/4 scale cub with a YS 120 and the one at the web site I mentioned hold mine with no problem what so ever. Also it will fold down by just pulling the aircraft back a little.

Mustang Man-RCU

rcpilot44,
As the ad states on the Tower Hobbies link, these restraints are intended for starting your plane. When you want to run it up, release it from the restraint and have a buddy hold it back. I have seen guys run their engines to max while the plane was still in the restraint and although I've never seen one come loose, I've seen quite a few dented stabs as a result. BE SAFE!!!!

crossed thumbs-delete

Mustang Man

This piticular restraint has foam insulation covering the vertical posts. No dents.

Mustang Man-RCU

crossed thumbs,
All the restraints I've seen have the foam covering but if you have a big enough engine you will still get dents in the leading edge of the stab. I've seen it happen on a half dozen planes. And although as I said I've never seen a plane break loose from the restraint, it's still not safe.

BillHarris

I tend to agree. The 20-40 pounds of thrust from a big engine is a lot to ask of tailfeathers to withstand.

Although it would be convenient to restrain a plane with a 4-stroke for setting the high-speed mixture at the field, it is safer to get a flyin' buddy to hold the plane.

I'll play around with the lay-down restrainer and a u-restrainer. I like to putter, so there....

Mustang Man-RCU

Bill,
Further to our discussion. I'm not familiar with the safety rules at AMA sanctioned events as I don't fly down there that often but up here in the great white north at MAAC sanctioned events you may start your plane while it is held by a restraining device but you may NOT run the engine up without it being held back by either another person or restrained by the back of the pilots legs. The second person then acts as your spotter. This rule applies to Big Bird or Giant Scale events.

Grampaw

I remember one club field that had sturdy pipes in the ground in front of the Pit area. These pipes were padded and spaced at approx. 24 inches apart all the way across in front of the Pits. When you were ready to start your plane, you took it out and set the fuselage between a pair of these restrainer pipes, with the wings against the pipes. No helper was necessary, and once you were ready to fly, you pulled it back out, turned it around and taxied out to the runway. Upon landing, you could taxi back in toward the pits, driving the plane between two pipes and shut it down. A runaway plane could run through these pipes after maybe breaking its wings off, but a hurricane fence was the next obstacle. It worked for all size planes, and was the best set up I've seen to date.

DBCherry

My Feedback: (4)

I have one that I bought on eBay a while back. It's similar to the one Crossed Thumbs posted a link to.

Cost me $18 shipped IIRC. I like it a lot, but the old really big screwdriver and piece of rope worked just as well.
Dennis-