A friend of mine just bought a Stinson 108.
He's got it torn apart some, just checking everything over and getting things squared away for it's first annual inspection in quite a while.
He found something that doesn't look right at all--
the aileron cables are crossed where they go up from under the floor to above the headliner, behind the baggage compartment.
Crossed to the point of rubbing- in fact, there's some plastic tubing over the cables & turnbuckles to prevent abrasion.
That tubing looks like it's been on there for a long time.
.Everything else looks right -- under the floor, and up the control column--
per the Univair-produced Stinson 108 manual that came with the airplane.
It specifically says that the aileron "idler" (carry-through) cable connects to the AFT arm of the aileron bellcranks.
However, we googled up an online manual (also produced by Univair)
http://jasonblair.net/wp-content/upload ... Manual.pdf
and it says they connect to the forward arm-- which would solve the goofy crossed-cable situation.

The carry-through cables were connected to the rear arm of the bellcranks before the wings were covered,
as there is no access to them now.
They're located aft of the aft spar, in the aileron cove, covered by fabric over metal.
Not an insurmountable problem to cut a hole to get to them, and make a cover,
we just want to make sure that this is the problem.
Can any Stinson guys out there confirm that the carry-through attaches to the forward arm of the bellcrank?
Thanks.

From the SM pics on pp. 43 and 48 it looks to me like the idler connects the rear bell crank arms.

For example if turning right the left yoke turns right and pulls on the column cable that passes to the right side going aft in the fuselage. That same cable then connects to the front of the right wing bellcrank to pull that aileron up. The idler cable is pulled to the right and then connects to the aft of the left bellcrank to push the left aileron down.

How you fix what's there now is another matter. Draw out a pic and post it for comments?

Gary

The first paragraph on page 47 in the online manual says the forward arms of the wing bellcranks are connected to the idler cable.
Pretty sure the online manual is correct, and the hard copy my friend has is a misprint.
Looking at the diagram....keep in mind that the bellcrank pushrod is connected to the bottom of the aileron--
a pull on the control cable will make the aft arm of the bellcrank go toward the fuselage,
the pushrod pushes the bottom of the aileron back, resulting in the aileron going up.

OK if the pic on p. 48 is FU then so am I. Not the first or last time.

Gary

The drawing does indeed seem to show that,
but the text says otherwise.
And the crossed cables on this airplane seem to bear out what the text says.

best thing would to be post on the yahoo stinson forum or the ISC site for information. There are many there that would be able to help.

Any observations to offer from your own Stinson?
KInda what I was hoping for with this thread.

http://www.hangar9aeroworks.com/Stinson ... atalog.pdf

There's pictures and part #'s here of the rigging. See pp. 6 and 44 plus P/N's. I don't see any crossed cabling. The idler cable #23 goes to the rear of the aileron horn

Gary

Any observations to offer from your own Stinson?
KInda what I was hoping for with this thread.

I am not in town this week and the plane is in the hangar. I will have look as soon as I can.

The stinson folk have a lot of knowledge and are helpful until i can get there.

Hardtailjohn, where for art thou?

MTV

PA1195 wrote:http://www.hangar9aeroworks.com/Stinson%20Tech%20Info/Univairpartscatalog.pdf
There's pictures and part #'s here of the rigging. See pp. 6 and 44 plus P/N's. I don't see any crossed cabling. The idler cable #23 goes to the rear of the aileron horn. Gary

You're definitely correct.

Well if I had the problem, and because I'm a visual guy, I'd draw out what's there now. Then I'd replicate the parts and maintenance pics and see which is the best and correct. Post them here....the diagrams, so maybe we can benefit from all this speculation as well.

I can do this in my head but that's above my current pay scale.

Gary

mtv wrote:Hardtailjohn, where for art thou?

MTV

It's been a few years, since I had to do one from scratch, but I sure don't remember them ever being crossed.
John

hotrod180 wrote:The first paragraph on page 47 in the online manual says the forward arms of the wing bellcranks are connected to the idler cable.
Pretty sure the online manual is correct, and the hard copy my friend has is a misprint.
Looking at the diagram....keep in mind that the bellcrank pushrod is connected to the bottom of the aileron--
a pull on the control cable will make the aft arm of the bellcrank go toward the fuselage,
the pushrod pushes the bottom of the aileron back, resulting in the aileron going up.

I went and looked at three Stinsons today because I like them and would own. Plus I didn't know how the ailerons were displaced from neutral as the pictures on pages 6 and 44 of the pushrod > aileron noted in the parts manual linked above are not very clear.

It appears to me that the pushrod for each aileron attaches above the aileron's hinge line which is lower in the aileron. As a result an extension of the pushrod rearward would deflect the surface down; a retraction of the pushrod would raise the aileron.

Maybe the service and parts info shown here is correct. If so, crossed cables are likely a fix for an earlier FU. Hopefully there are available cable connections that can be undone and the problem corrected.

Gary

I've been away from my 108 for months, and won't see it again soon; however, Univair has pretty good tech support for this type of stuff. Give them a call, I bet they can sort it out for you over the phone, or at least email you some clearer drawings.

PA1195 wrote:….Maybe the service and parts info shown here is correct. If so, crossed cables are likely a fix for an earlier FU......

I'm sure that was the case.
The owner decided to cut into the wing & switch cable connections at the aileron bellcranks.
Then uncrossed the cables on their vertical run.
All good now.

That's good news he was able to identify and rectify the problem. I've been around but never flew a Stinson. Wish I had now as they are available for reasonable prices and seem comparatively well supported. One local has an O-470 I believe in one with a long prop. It sits on EDO 2425's but never flys. I watched it a few times when it did and wow! nothing wrong with that conversion. Others locally periodically sit and change owners (for example: https://fairbanks.craigslist.org/avo/d/ ... 71634.html) plus there's a 108-1 with a 150 Franklin that's been sound asleep for years. The owner's in his '90's by now but it does get snow removed. Sad to see it parked.

They can have extended wings and tips, VG's, power added, and would make a fine airplane if the engine and prop were right.

Gary

I've done a few of the O-470's and they're an awesome aircraft!!!
John

Maybe Stinson will become the latest find for value like the Pacer/Tri-Pacer and Aeronca Sedan. Seems everything else with a low profile has been mined and when reported the rush is on. I'd own one if the engine can still be maintained.

Not sure about engines tho. Is Franklin still available? (http://www.franklinengines.com) It takes power to propel weight and pounds per wing area is a reality unless enhanced lift devices are available. If the engine is toast then again there's the cost of an overhaul or changeout versus aircraft value when done.

Here's some specs to consider:

Stinson: https://en.wikipedia.org/wiki/Stinson_108
Pacer: https://en.wikipedia.org/wiki/Piper_PA-20_Pacer
Sedan: https://en.wikipedia.org/wiki/Aeronca_Sedan

Gary

Lotsa engine upgrades possibilities for a Stinson 108--
220 Franklin (not well supported, I think), 360 Lycoming, IO360 Continental, O470 Continental...
there's also a few around sporting a 540 Lycoming and fixed pitch prop (maybe off a Pawnee?).
The 470 and c/s prop seems to me to be the way to go--
it's no Cessna 180 (had to say that, brand loyalty you know!) but it comes pretty darn close!