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It’s my understanding the factory recommends a winch should not be used on the tail strake to pull a DA40 into a hanger. The tail strake is attached to the hull with 6 bolts and was not designed for that purpose. My personal experience is that we used a winch for 9+ years on our 2007 DA40 and never had any problems. However, it’s clear that one could damage the strake if it is yanked sideways with a lot of force in the process of pulling the plan into the hanger.

To address this, I created a simple harness that attaches the winch to the landing gear instead of the tail strake. The amazon.com parts list for this harness is pretty simple:

• 2” x 10 yards webbing (https://www.amazon.com/gp/product/B01KT ... UTF8&psc=1)
• three 5.5” carabiners https://www.amazon.com/gp/product/B07GQ ... UTF8&psc=1

As shown in the pictures below, two loops were sewn into the webbing on each end and a third loop was sewn in at the center point. The harness is attached by looping each end over one of the landing gear struts (from behind the wing) and connecting the two sewn-in loops with a carabiner. A third carabiner attaches the winch to the webbing midpoint loop. The midpoint loop is used to make sure the winch pulling point always stays centered.

Press down on the tail to lift the nose wheel off the ground slightly (since it never seems to be aligned straight) as the plane is pulled into the hangar by its landing gear.

See the youtube video (https://www.youtube.com/watch?v=ukcsFxnyigQ) to see the harness and winch in action .

If you had a longer control cord you could use you tow bar to steer the airplane and not have to push down on the tail.

Shouldn't those yellow straps be higher on the struts so that there is less leverage on the connection to the fuselage?

Colin wrote: ↑Wed Nov 27, 2019 6:45 pm Shouldn't those yellow straps be higher on the struts so that there is less leverage on the connection to the fuselage?

Colin:

Negligible, compared to the loading when landing. Also, remember that the tow bar (or tug) connects to the nosegear at the roughly same lever arm, and moves the entire mass of the aircraft.

Steve

I thought about moving the straps up higher but decided it would be better to keep them low to make sure they don't bump the antennas on the bottom if you happen to pull from the side when the plane isn't lined up straight. Since the winch is right on the hangar floor, it pulls pretty much straight back on the landing gear where the wheels attach.

@MarkA

I have been using a winch attached to the tail tie down of my DA40 for three years. While I have not had any issues with doing so, the question of whether the tail tie down should be used that way has come up, repeatedly. Interestingly, my own YouTube video at https://www.youtube.com/watch?v=5BShoqQG2G8 looks a lot like yours, although it appears that you are using a heavier duty AC powered winch.

You have definitely given me an idea of how to create a harness similar to yours using braided yacht line, rather than the nylon straps you used, as I have a lot of the braided line, and I like to make eye splices in it. I will look into that approach when I have some time.

Thanks for sharing your own innovative approach.

Sandy

The nose gear is designed to tow the airplane. They have attachment points for towing and give you a tow bar. They don't do that for the main gear. And I agree that the load of a (bad) landing is much more than pulling the plane backwards into a hangar, it is also a force that is applied in a differently direction on that connection. Antoine?

Colin wrote: ↑Sat Nov 30, 2019 3:10 am The nose gear is designed to tow the airplane. They have attachment points for towing and give you a tow bar. They don't do that for the main gear. And I agree that the load of a (bad) landing is much more than pulling the plane backwards into a hangar, it is also a force that is applied in a differently direction on that connection. Antoine?

Many (particularly tailwheel aircraft) are towed by their main gear (my friend's P51D Mustang comes immediately to mind). I would restate that the rearward load on the main gear is more than the load imparted by the tow cable even in a good landing, or even normal braking.

If you have ever looked at the main gear attach points on a DA40, they are quite robust.

Steve

Steve wrote: ↑Sat Nov 30, 2019 3:37 am Many (particularly tailwheel aircraft) are towed by their main gear (my friend's P51D Mustang comes immediately to mind). I would restate that the rearward load on the main gear is more than the load imparted by the tow cable even in a good landing, or even normal braking.
Steve

And the substantial form drag on the main gear in normal flight, to say nothing about redline. It just doesn't take that much fore-aft force to move the plane on the ground. Think how little you're actually exerting with the towbar.

I did have my skid plate mount come loose (presumably from lateral force) in the few years it was tied down outside. At KPAE, when we would get substantial winds, they were almost always yanking hard against the left side of the airplane, pulling laterally against the tail tiedown. And often had a strong gusting action.

I have been using an AC powered Harbor Freight winch tied to the tails kid for about 4 years. I added an extra length of cable and an extension to the wired controller. I have the controller with me in the front of the airplane and use the towbar to steer the nosewheel. So far no problems with the tail skid.