diamondaviators.net

Yikes! Here's a report on the collision which severed the tail of G-CDEK. It's not clear whether the spinning prop did most of the damage, but I would expect so.

Lance Murray wrote:The glider towing kit is a good point. Has anyone ever seen one? How is it connected to the airplane?

Here's a link to the only image I could find of a DA40 with a tow attachment.

I'm thinking the only risk of using the tail fin as a tow point would be to the fin itself - particularly at the attach points. I can't see it causing the empennage to fail.

That is a very painful set of images to see! Ouch! You can see where the C-150's prop hit the tail in a downward motion, but still ...

If we assume that the prop was moving at an idle speed (as the accident report suggests) then the tip of the 70 pound propeller were moving at 300-400 MPH. I'm too tired to figure out the actual pounds given rotation, etc., but suffice it to say it is likely a lot more painful force vector than what a typical winch would produce.

Pretty much EVERY DA40 accident photo I have seen shows the tail snapped off. Not chopped off by a propeller. The tail empennage is a weak point. Strong enough for flight forces but doesn't survive the accidents.

Winch recommendations?

Are there any features that are helpful?

@soarer20

I made a YouTube video showing the winch that I used and how it's installed. You can see it at https://www.youtube.com/watch?v=5BShoqQG2G8

I responded there to a request for further information, as follows...
In order to install the winch (a Harbor Freight 2500# 12v winch that comes with a wireless remote), I first mounted the winch to a piece of 3/4" plywood. The dimensions of the plywood are not critical, as long as it is large enough to have some clearance around the winch. I also mounted a Harbor Freight ATV/Utility WInch Mounting Plate to the plywood in front of the winch. To mount the plate you will need to rout or chisel out the plywood, as the plate needs to be recessed relative to the winch. Then, mark and drill mounting holes through the plywood, and paint the plywood (top and bottom) to protect it from moisture, as it will be in contact with the cement floor. I used T-nuts on the bottom of the plywood, as they will allow removal of the winch after the plywood base is affixed to the cement floor. Next I located the rear center of the hangar, and I applied construction adhesive to the bottom of the plywood base. I used .22 caliber Ramset fasteners to attach the base to the floor of the hangar. The winch is powered by a Harbor Freight 12v Portable Power Pack that I turn on only when I use it. This configuration is totally portable, so no AC connection, and no wired remote are needed. To connect the clip on the winch to the plane I use a Harbor Freight 5" Jumbo Aluminum Hook. Altogether, on sale, the winch and Power Pack were $49.99 each, the Mounting Plate was $4.99, and the Aluminum Hook was $1.99. From Home Depot I got the 1/4" T-nuts and 1/4" bolts, the construction adhesive, and the Ramset fasteners.

It's also important to paint lines on your hangar floor corresponding to the main wheels, so that you can keep the plane aligned as you bring it into the hangar.

If you have any questions, feel free to contact me, but be assured that the specified HF winch, with remote, and the 12V power pack are all you need. There is absolutely no need for 120V.

Sandy

I just posted my solution for winching my DA40 in reverse from the nose gear. An easily homemade rig for attaching to the normal tow bar points and pulling from both sides. Works fantastic and no problems potentially damaging the tail tie down:

viewtopic.php?f=8&t=7098&start=30