Pawnee Tow Release

It's an "R" model and I can forward you the FAA form 337 paperwork they have on file for the engine if you want. Thanks for the useful tips; we'll follow up.
Mike

Not necessary I was just curious. Give me a call if you have any questions. Your local IA should be able to approve the install.

On Sunday, September 15, 2019 at 3:36:07 PM UTC-7, Duster wrote:
We are looking to purchase a Pawnee PA-25 that had a Continental engine installed (230hp?). It is approved for aerial towing (Schweizer hook) and we are trying to decide if it's worth the time/money to seek an FAA conversion to towing gliders with a TOST. Have read through several of the RAS discussions on this and talked with a couple clubs that completed STC's/FDSO field inspections. I get the feeling it's a real headache, some people concluded they wouldn't do it again. Anyone have a better experience or advice?
Thanks
D

See if the Pawnee is certified as "Normal" vs. "Restricted". If it is in the "Restricted" category, the "special purpose" will be on the Airworthiness Certificate and it needs to say "glider towing" - not "banner towing" - in order to legally tow gliders.

On Monday, September 16, 2019 at 11:22:06 AM UTC-4, Charles Longley wrote:
Interesting that someone put an O-470 on a Pawnee. Do you know which model it is?

To answer your question the TOST tow release comes with an STC. W&W does a pretty good job supporting them.
Here’s the standard one-
https://wingsandwheels.com/aircraft-...-for-pa25.html
If your club wants to spend a lot more money and go to a retractable one here’s the link-
https://wingsandwheels.com/aircraft-...-for-pa25.html
Pros and cons for each. Depends on how your club operates.

I would put the release in front of the throttle where the pilot can easily see it. One of the Pawnee’s I fly is set up that way. The other two use the stock dump lever. Which is acceptable but not as convenient to reach.

Any IA can sign off the FAA form 337 to document the conversion. The approved data will come from the STC and AC 43.13.

Hope this helps.
Charlie

The TOST DOES NOT come with a STC. It comes with an EASA1 European form not a STC. Read 43-13-2A Chapter8, page 73-75, Circular adv. This is not as difficult as one might think. Bob

On Monday, September 16, 2019 at 2:43:06 PM UTC-4, Walt Connelly wrote:
'Duster[_2_ Wrote:
;1000607']We are looking to purchase a Pawnee PA-25 that had a
Continental engine installed (230hp?). It is approved for aerial towing
(Schweizer hook) and we are trying to decide if it's worth the
time/money to seek an FAA conversion to towing gliders with a TOST. Have
read through several of the RAS discussions on this and talked with a
couple clubs that completed STC's/FDSO field inspections. I get the
feeling it's a real headache, some people concluded they wouldn't do it
again. Anyone have a better experience or advice?
Thanks
D

"Trying to decide if it's worth the time/money?" Time and money should
not enter into the equation when the life of your tow pilot may depend
on the TOST release. If you don't care about the life of your tow pilot
then by all means keep the Schweizer hook. While you're at it you might
give consideration to placing the release handle where the pilot can
quickly access it in the upright, seated position. JMHO

Walt Connelly
Former Tow Pilot




--
Walt Connelly

I think that Walt has pretty much summed up the situation. Walt has see my towplane release arrangement and commented on what he saw on the Yellow Gorilla, simply put, it is SAFE, but not fool proof. Get that release handle where it is within easy reach of the pilot.

On Monday, September 16, 2019 at 10:51:07 AM UTC-7, Bob Youngblood wrote:
On Monday, September 16, 2019 at 11:22:06 AM UTC-4, Charles Longley wrote:
Interesting that someone put an O-470 on a Pawnee. Do you know which model it is?

To answer your question the TOST tow release comes with an STC. W&W does a pretty good job supporting them.
Here’s the standard one-
https://wingsandwheels.com/aircraft-...-for-pa25.html
If your club wants to spend a lot more money and go to a retractable one here’s the link-
https://wingsandwheels.com/aircraft-...-for-pa25.html
Pros and cons for each. Depends on how your club operates.

I would put the release in front of the throttle where the pilot can easily see it. One of the Pawnee’s I fly is set up that way. The other two use the stock dump lever. Which is acceptable but not as convenient to reach.

Any IA can sign off the FAA form 337 to document the conversion. The approved data will come from the STC and AC 43.13.

Hope this helps.
Charlie

The TOST DOES NOT come with a STC. It comes with an EASA1 European form not a STC. Read 43-13-2A Chapter8, page 73-75, Circular adv. This is not as difficult as one might think. Bob

I've only put one on and it was a couple of years ago. I thought it had an STC. Call W&W to check. My memory isn't perfect. I do remember it being a relatively easy install and 337. Correct on AC 43-13-2A. That's the data I used. Not a big deal.

I 100% agree on getting rid of the Schweizer hook! I wont tow with one. The sense I got from the Mike (duster) is they want to put one on but need to research cost. With a club it needs to be approved by their board typically.. I am more than happy to provide info to make it safer.

On Monday, September 16, 2019 at 4:41:58 PM UTC-4, Charles Longley wrote:
On Monday, September 16, 2019 at 10:51:07 AM UTC-7, Bob Youngblood wrote:
On Monday, September 16, 2019 at 11:22:06 AM UTC-4, Charles Longley wrote:
Interesting that someone put an O-470 on a Pawnee. Do you know which model it is?

To answer your question the TOST tow release comes with an STC. W&W does a pretty good job supporting them.
Here’s the standard one-
https://wingsandwheels.com/aircraft-...-for-pa25.html
If your club wants to spend a lot more money and go to a retractable one here’s the link-
https://wingsandwheels.com/aircraft-...-for-pa25.html
Pros and cons for each. Depends on how your club operates.

I would put the release in front of the throttle where the pilot can easily see it. One of the Pawnee’s I fly is set up that way. The other two use the stock dump lever. Which is acceptable but not as convenient to reach.

Any IA can sign off the FAA form 337 to document the conversion. The approved data will come from the STC and AC 43.13.

Hope this helps.
Charlie

The TOST DOES NOT come with a STC. It comes with an EASA1 European form not a STC. Read 43-13-2A Chapter8, page 73-75, Circular adv. This is not as difficult as one might think. Bob

I've only put one on and it was a couple of years ago. I thought it had an STC. Call W&W to check. My memory isn't perfect. I do remember it being a relatively easy install and 337. Correct on AC 43-13-2A. That's the data I used. Not a big deal.

I 100% agree on getting rid of the Schweizer hook! I wont tow with one. The sense I got from the Mike (duster) is they want to put one on but need to research cost. With a club it needs to be approved by their board typically. I am more than happy to provide info to make it safer.

I do recall that the Pacific Aero tow hook does have an STC for some models, but not the PA25. They do have it on the PA18 and a couple of others. I recently purchased a Pacific Aero unit that I plan on doing considerable testing to determine the integrity of the hook. My first observation is that it is a redesign of the old Schweizer hook but is much improved and the ring cannot slide for ward on the assembly. This along with the hopper dump handle as the release arm should prove to be an excellent assembly, but only time and results will come into the conclusion.

Good point; the one of interest to us had earlier been incorrectly categorized as "Normal" which the FAA since corrected to read "Restricted; aerial advertising, Other- Banner Tow, Glider Tow". The "Time and Cost" concern regarded converting this Pawnee from banner towing with Schweizer release to glider towing w/Tost release. We love our tow pilots.

.....though sometimes that's not so obvious. This summer a misplaced tow rope got sucked into our tow plane's prop. Only one tow after the engine was replaced and prop overhauled; and while towing a twin Grob (single pilot), rear canopy started to raise @ 2,500', glider nose pulls up, tow plane's tail goes vertical, rope breaks, tow plane enters spin, spin recovery but becomes inverted, tow pilot recovers at 500' AGL. Finally the tow plane and glider land safely but both front and rear glider canopies have departed (front one broke loose possibly when cockpit items shattered it when in negative g. We are so thankful the tow pilot's vast experience got him out of that mess!

Wow good job on the tow pilots part!

Originally Posted by Bob Youngblood

On Monday, September 16, 2019 at 2:43:06 PM UTC-4, Walt Connelly wrote:
'Duster[_2_ Wrote:
;1000607']We are looking to purchase a Pawnee PA-25 that had a
Continental engine installed (230hp?). It is approved for aerial towing
(Schweizer hook) and we are trying to decide if it's worth the
time/money to seek an FAA conversion to towing gliders with a TOST. Have
read through several of the RAS discussions on this and talked with a
couple clubs that completed STC's/FDSO field inspections. I get the
feeling it's a real headache, some people concluded they wouldn't do it
again. Anyone have a better experience or advice?
Thanks
D

"Trying to decide if it's worth the time/money?" Time and money should
not enter into the equation when the life of your tow pilot may depend
on the TOST release. If you don't care about the life of your tow pilot
then by all means keep the Schweizer hook. While you're at it you might
give consideration to placing the release handle where the pilot can
quickly access it in the upright, seated position. JMHO

Walt Connelly
Former Tow Pilot




--
Walt Connelly

I think that Walt has pretty much summed up the situation. Walt has see my towplane release arrangement and commented on what he saw on the Yellow Gorilla, simply put, it is SAFE, but not fool proof. Get that release handle where it is within easy reach of the pilot.

There is NO foolproof system, if the glider kites suddenly at a low enough altitude the tow plane will go in with potentially catastrophic results. I'm not talking about the slow, annoying type of kite, I'm talking the tow plane going from staight and level to nose steeply down in the wink of an eye, it happens. My concern is that a known deficiency in both the Schweizer hook and the position of the release continue to prevail. IF the Schweizer hook is to be used it must be inverted and the release handle needs to be such that it is immediately available to the pilot in the upright, seated position. If your IA can't figure out how to do this get another IA.

Walt Connelly
Former tow pilot
Now happy helicopter pilot.