Just a note. I sent back 2 sets of mains to Robart yesterday. These are the springdown type. The problem is that when these are mounted the slightest bit of pressure on the flanges (ie mounting them) causes them to drag and not lock in the down position. I will report to the community on what they do.

Andy

sorry to say that you will find that the boomer mounting rails are not all flat and equal with each other - the cure to your problem is to put a washer or some shim stock under the offending low spot - it is trail and error - but i bet your retracts were fine . i even had to due this to the high quality jet a1 retracts and struts that would sometimes hang up even with air down!!!!!

now that is impossible....
ours can not deform by any chance .
robarts cosinst of frames bolted together ,where the jet-1a have cnc machined body,s impossible to deform.
the only thing that woud deform is the model..
as for them to get locked in a up position , is due to the oleo or wheel gets stuck somewhere in the fuselage.

This particular set of Robart gear has known problems that they (Robart) are working on solving. When I last spoke to them about this in July, they could not forecast a date when the problem would be fixed. These gear would not stay locked in the down position, even when you manually pushed everything into the "locked" position.

So, while waiting for a fix for this set of gear, I have a $300+ set of retracts that are unusable.

Update: 10/4/07: Just got off the phone with Robart. They at present, are replacing the cylinders on all Boomerang XL II spring down retracts with air up/down cylinders. They told me that Boomerang has returned ALL of their spring down retracts that they had in stock and that Boomerang is now only selling air up/down type retracts. This has also been independently confirmed with Boomerang by Neal Newell.

Apparently there is a design flaw that their engineers are working on. They did not get into specifics but I believe it has to do with the spacing issue and something internal to the cylinder.

They are changing out all of the cylinders on the retracts that I sent them. Along with that they are sending ample air tubing and valves to each of their customers who send these gears back for warranty repair. I don't use their air tubing because I have heard that it will leak over time, but I will use the valve to get me by.

Andy

did you gave them our number?
cant imagine sending out a gear that doesnt work..

They lock fine in the up position - its the locking in the down position that is the problem. Once the wheel is already DOWN, they will only lock randomly. After repairing wing tips and flap tips a half dozen times I got tired of it. At one point I was just flying with them down all the time. Because once you do get them to lock they stay locked. But hey, why have retracts if you can use them?

In all of my flights on the BXL I have not had one instance where the digitech gear did not extend.

Gary Szetlak

Good send them to me and MY problem will be solved.

My thanks to Robart for the great & fast service on converting my air up & springdown retracts to air up & down.
( One week )

Jimbo

Just a note to anyone sending parts back to Robart. Be sure you get delivery confirmation of your shipment to them and keep the receipt no matter what. I sent some hardware back to have a replacement completed. I did not get delivery confirmation but I did get a phone confirmation the shipment was received. After some delay I called to check on my status and it was denied the parts were received. It was a simple mistake but I ended up paying for it. This was two years ago but unfortunately something like this just sticks with you, so be sure to get the tracking and keep the info.

Back to the retract issue. I have a pair of 700 series air up, spring down. I bought the units last summer and they work like a charm. Does anyone know if this particular issue is restricted to the boomerang gear or is it effecting all of the air up, pring down gear made by Robart? Just wondering if I should be looking for anything in particular. Is the problem there from the start or does it get worse over time, etc.

As far as I know, this only applies to the special series of gear that they made for Boomerang.

It applies to the 700 robart spring down series, as Robart told me. I have a 737 robart retract, that of course, doesn´t work. As I live in Spain, ask robart to send me the new air up air down cilynders, to change for myself. ( I blocked the secure pin with a plastic tie, and I can fly as a fixed gear while they send the spare parts).