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Glider Tow Hook Installation
Posted: Thu Feb 15, 2007 7:49 pm
by GAHorn
I have received a question from a Cessna 170A owner regarding installation of tow hooks. Does anyone have an approved installation or know of a source?
Posted: Fri Feb 16, 2007 4:00 am
by blueldr
The only one I've ever seen was fastened to the tail wheel mounting bolt with the release lever connected to a long Bowden control terminating in a lever at the rear of the tunnel in the cockpit.
The owner claimed it was designed to tie the tail for emergency starting by hand propping.
Aside, he admitted it was for glider towing. It probably did not have any official approval.
He claimed the installation was copied from one used for banner towing.
Posted: Fri Feb 16, 2007 4:44 am
by pdb
I have an approved installation and use it a few times a year for light gliders. My 170B with the O-300 is not an ideal glider tug although its adequate for light, single seat gliders if you are patient. If you are towing 2 place gliders or water ballasted gliders I would suggest you are nuts.
I am towing from near sea level, in generally cool conditions, with the rear seat removed, half tanks, and an 80-42 prop to boost climb.
I have a good picture of the installation but have never been able to figure out how to post photos here. I also have a gorgeous picture of the 170 towing a Russia AC-5M near Mt. McKinley to prove we have done it. If someone will volunteer to post the photos, I will email them along. I do not have but I could easily make a photo of the release handle installtion which uses the flap tunnel. Its a very nice installtion.
The towhook is not a bad mod for other purposes as well. Its extremely useful for floatplanes operating on rivers as well as anyone who has to hand prop.
I would be happy to provide the details of the installation for anyone who has serious intentions of installing one but I don't want to go to the hassle of and expense of copying and sending then out to tirekickers. BTDT. The photos however would be very helpful to folks considering the mod.
Pete
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Posted: Fri Feb 16, 2007 5:23 am
by hilltop170
Pete-
Email them to me and I will post them.
Posted: Fri Feb 16, 2007 7:31 am
by GAHorn
Thanks Pete!
I have an inquiry from one of our International friends who originated the discussion. If you can email me I'd appreciate it. I also need any copies of approval basis you may provide. (My email address is on the cover of the flypaper and in the directory...or you can send it to ghorn (at) cessna170 (dot) org.)
Posted: Fri Feb 16, 2007 2:12 pm
by N1478D
pdb wrote: . . . I also have a gorgeous picture of the 170 towing a Russia AC-5M near Mt. McKinley . . .
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Doug . . .
Posted: Fri Feb 16, 2007 4:43 pm
by doug8082a
N1478D wrote:pdb wrote: . . . I also have a gorgeous picture of the 170 towing a Russia AC-5M near Mt. McKinley . . .
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Doug . . .
Email me a hi-res copy! Sounds like a great candidate for the 2008 calendar! my email address is on my profile or click the email button below.
thanks for catching that Joe

Posted: Fri Feb 16, 2007 8:08 pm
by lowNslow
Years ago I flew several 170s with tow hook installations. I don't remember the approval basis, but I am pretty sure it was on a 337 field approval. I think Schweitzer only had STCs for PA-18s. You might want to check with
AirRepair or some of the other L-19 operators, far more of these are equiped with tow hooks then 170s, but the installation should be very similar. By the way, I notice
McFarlane is selling a improved Schweitzer type hook.
Posted: Thu Feb 22, 2007 4:31 am
by hilltop170
I tried to post the photos for Pete but could not. They came up as .bmp instead of the .jpg I'm used to posting. Is that the reason they won't post?
Posted: Thu Feb 22, 2007 12:42 pm
by Bruce Fenstermacher
Richard most likely the problem. If you can't convert them send them my way and I will do it and post them.
Posted: Fri Feb 23, 2007 2:37 am
by Bruce Fenstermacher
Here are the photos Richard tried to post for Pete.
Doug I think you might have a winner for the back of the calendar. It's high res to.
Posted: Fri Feb 23, 2007 3:42 am
by blueldr
It seems to me that the U bolts used to mount the tow hook attaching plate would take out any possible flexing ot the tail gear spring assembly.
The installation I've seen had the tow hook attaching piece fastened under the tail wheel mounting bolt which in the above picture happens to be a ring bolt for tie down.
Posted: Sat Feb 24, 2007 2:15 pm
by doug8082a
Already got a hi-res copy of the pic Bruce! It's in the mix for 2008!
Here are some photos from Andrew Dunlap of his installation.

Posted: Sat Feb 24, 2007 5:38 pm
by blueldr
The photos above by Dunlap are ,by far, the best I've ever seen on my screen, bar none. (Detail, Resolution, Color, Etc.) Congratulations.
Posted: Sat Feb 24, 2007 7:04 pm
by iowa
i agree w/BL
very, very nice pics!!
when i was a med resident
i flew out of CLOW airport.
they flew a lot of gliders there.
i never did.
iowa