Tow Limits Exceeded

PatternBreak

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Having worked with and as line service and towed aircraft, I'm always surprised when pilots depart without preflight and just hope nothing has been broken while they were away.

My question is what would happen to a GA aircraft if the turn limits were exceeded, and if there are any generic items that can be checked on preflight to ensure that all is as it should be.

I know on Beachcrafts the pins you put the bar on will sheer, but besides that there seems to be no comprehensive way to know if damaged has occurred. For the vast majority of piston singles my company as well as many others are instructed that the turn limits are 15° per side. (10° in Mooney's)
 
Some have sacrificial stuff that breaks, but in the sub 300hp piston world think it’s mostly just if it looks bent or doesn’t handle right anymore, doubt many 172/PA28/SR folks would catch it unless you really fubared it.
 
The nose gear on my 182RG wouldn't lock down once. That was an expensive landing. Mechanic said that if the nose gear was turned to far it could break the collar which would prevent gear from extending far enough to lock. Or something along those lines (it was almost 15 years ago).

He did say it would have been very difficult to determine during pre-flight.
 
Mooney pilots are very conscious of this as unfortunately we hear every year several cases of line folks exceeding the turn limit and causing damage. In a Mooney it’s easy to tell if you take the time to look. There is a specific location where the landing gear makes contact and if there is a dent there then your are done! A new truss is required. My Mooney has an aftermarket nose strut that has built in stop bolts to prevent damage if turn limits are exceeded but there have been cases where even the stop bolts have been sheared off by line man using a tug and severely exceeding turn limits. ALWAYS CHECK!!!


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Mooney pilots are very conscious of this as unfortunately we hear every year several cases of line folks exceeding the turn limit and causing damage. In a Mooney it’s easy to tell if you take the time to look. There is a specific location where the landing gear makes contact and if there is a dent there then your are done! A new truss is required. My Mooney has an aftermarket nose strut that has built in stop bolts to prevent damage if turn limits are exceeded but there have been cases where even the stop bolts have been sheared off by line man using a tug and severely exceeding turn limits. ALWAYS CHECK!!!


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The newer Mooneys have a highly visible limit indicator and I believe the stops like you're talking about. We use the same tugs on the G550's as we do the pistons, so any mistake and it's conceivable that you'd rip the nose off. This 1996 M20Rs indicator would snap if you went past limits would it not?
 

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The newer Mooneys have a highly visible limit indicator and I believe the stops like you're talking about. We use the same tugs on the G550's as we do the pistons, so any mistake and it's conceivable that you'd rip the nose off. This 1996 M20Rs indicator would snap if you went past limits would it not?

No. You'd just bend the landing gear all up and likely never know it unless you got on your hands and knees and looked up in the nose gear well. Those indicators are just a little piece of flat steel clamped around a tube and are often loose and vague.
 
When line folks did that to my Piper it fractured a cast piece on the nose gear oleo that is part of the shimmy dampening system. Hairline fracture you would almost certainly not notice on a preflight. But as soon as I tried to taxi the airplane it would steer only in one direction. That was how I was able to prove conclusively to the FBO the airplane did not arrive in that condition. We had to crawl under the airplane with a bright flashlight to see the fresh hairline fracture.
 
I haven't asked line to tow my plane in years. Never found it relocated either. I do all hangar moves myself.
 
No. You'd just bend the landing gear all up and likely never know it unless you got on your hands and knees and looked up in the nose gear well. Those indicators are just a little piece of flat steel clamped around a tube and are often loose and vague.

You'll know it at annual time $$$$$ :cryin::cryin::cryin::cryin:
 
I've only let my airplane out of my sight once for tow, and yes I've got a dent (my mechanic says it's OK). Never again.
 
Yeah, I can tell you on the Navion. Exceeding the turn limit bends the nose gear scissor. Jackasses at IAD did that one day.
 
My Bonanza has pin, about 3/16 diameter that the tow bar hooks onto. If you turn to0 tightly this pin will shear. I have had it happen 3 times or so in 15 years, and in the latest case the line men apologized and replaced the pin, doesn't take much. Ive never had any damage to the gear.
 
Beech uses tow pins that snap....they're like $20 to replace. Most other planes just break. As a former line guy, Mooney's are by far the biggest PITA to tow
 
Makes me appreciate the design on the Grumman and the Cirrus

PS I had a Delta flight delayed once about 2 hours when we were backing out of the gate.. the turn seemed sharp, almost like we started moving forward again and there was a tremendous bang inside the cabin, the whole plane shook, and we stopped moving and the ground crew's faces were priceless..

after half an hour of not moving they towed us over to a maintenance hangar only to be told that yes the plane cannot fly and we had to get towed all the way back to the gate and find a replacement plane
 
Put the wheel on the back of the airplane where it belongs and you have no problem!
Believe me if that was an option then some of the guys I read about would do it. Atleast at my work you can break anything and as long as you report it you won't be fired. You lie about something as small as a static wick and you'd best pack up your stuff. Still sometimes people wont report going past barron tow limits :/
 
Makes me appreciate the design on the Grumman and the Cirrus

PS I had a Delta flight delayed once about 2 hours when we were backing out of the gate.. the turn seemed sharp, almost like we started moving forward again and there was a tremendous bang inside the cabin, the whole plane shook, and we stopped moving and the ground crew's faces were priceless..

after half an hour of not moving they towed us over to a maintenance hangar only to be told that yes the plane cannot fly and we had to get towed all the way back to the gate and find a replacement plane

Cirrus are awefuly annoying to push back with that castering nose wheel. Our book lists the limits as 15° but does anyone know what they really are? Also the old Grumman's have magnesium(?) brakes and in between the old timers at my work 5 have been burnt to the ground. So everything's a compromise I suppose
 
Put the wheel on the back of the airplane where it belongs and you have no problem!
We don't have towbars for small GA tail wheels (just large fighters) so either taxi to the hanger and I'll help push it in like you're an old RAF fighter or enjoy the element's. (Hopefully no frost or hail forecasted)
 
Cirrus are awefuly annoying to push back with that castering nose wheel. Our book lists the limits as 15° but does anyone know what they really are? Also the old Grumman's have magnesium(?) brakes and in between the old timers at my work 5 have been burnt to the ground. So everything's a compromise I suppose
15* left and right? There is no way that is correct. If you step on the left or right brake you can pivot the plane pretty much around

people riding the brakes in the Grumman and free castering nose wheel planes are just poorly trained and like taxing at 1500 RPM with their feet on the brakes

pushing the plane back is not that difficult, you just have to have a firm grip on the tow handle and not get carried away sprinting the plane backwards.. I find it easier to maneuver into a tight spot

But as with most things in life, there are compromises everywhere
 
I see so many passenger jets with the tailwheel mod.

800px-Concorde_-_Tail_bumper_wheel_and_the_four_Olympus_engine_nozzles_%287181579366%29.jpg

 

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15* left and right? There is no way that is correct. If you step on the left or right brake you can pivot the plane pretty much around

people riding the brakes in the Grumman and free castering nose wheel planes are just poorly trained and like taxing at 1500 RPM with their feet on the brakes

pushing the plane back is not that difficult, you just have to have a firm grip on the tow handle and not get carried away sprinting the plane backwards.. I find it easier to maneuver into a tight spot

But as with most things in life, there are compromises everywhere
I know the sr22's and 20's can caster greater than that but thats just what out tow guide says :/ we use tugs for everything. You get good at fitting a 38' wingspan airplane into a 40' hanger with no room to backup after you do it scores of times. Across all types I tow ~10-30 aircraft per day

At my airport we routinely tow aircraft 1-2 miles so its partially set breaks that cause fires. Theyll roll with no resistance right until they start smoking sadly. Thats the problem when using 8000lbs tugs
 
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