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I see Roscoe got the Pre- ’77 AA-5 series Parts Manual posted here. This answered a couple of things I was wondering about.
Here is the list of nose struts by SN for the AA-5s.
702057-505 Strut – AA5-0001 thru AA5-0376, 0381, 0382, 0383, 0384, 0386, 0387, 0388.–506 Strut – AA5-0377 thru AA5-0380. AA5-0385. AA5-0389 and on.
-507 Strut – AA5B-0001 and on. AA5A-0001 and on.
Also as I expected, the nose torque tube bolts at the side of the fuselage show the AN176-7A bolt that I have had issues with on my AA-1s. I think going forward anyone installing a nose strut torque tube should install AN176-10A bolts here, as used on the ’77 and later AA-1C and AA-5s. The -7 bolts do not have the proper grip length and on both of my planes the plate on the end of the torque tube is resting on the threaded section of the bolt. I had one of these shear on my AA-1B, and on both planes all 4 bolts show wear.
The bolts in the attached picture show the four bolts (-7As) I removed from my AA-1 project (with just over 3,000 hours in service), a -10 bolt, and the last one is a bolt I removed from my ’76 AA-1B some 10+ years ago (also about 3,000 hours in service when removed after another bolt had sheared). if you look at the 5 shorter bolts you can see the wear on the threads, that compared to the -10A bolt it would resting on the solid part of the close tolerance bolt, not the threads.
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Hi,
Interesting post. I have also a torque tube issue. There are a lot of AA5 (AA5A, AA5B also later years of production) out there with no bolt on the outside brackets! I think this is a big risk and wonder why nobody is talking about.
I saw there are different modified torque tubes out there. One with taper pin, other with one bolt and another with two bolts 90 degrees offset on to bracket where it is mounted to the fuselage. Perhaps two bolts also reduce the material durability?
Which one is the preferred torque tube modification?Does anyone know which adhesive is used for the cold bonding on tube jointing sleeves and which size of bots should be used?
Regards
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If any of the side bolts are missing on the outside brackets this would definitely weaken the nose strut and could lead to a failure. It should be noticeable with the plane having less prop clearance.
Checking the log books on my AA-1B it was actualy 20 years ago I found the sheared bolt. This led me to pull the nose strut torque tube out of the plane for a close inspection. I found no issues, so I cleaned it up, repainted and reinstalled new hardware. I remember I purchased new hardware from Fletchair. Not knowing what bolts I had installed back then I pulled one out during the last annual and found it was a -10A bolt.
Attached is a picture of the center of the torque tube out of my Yankee project (before I cleaned it up and painted it). In the early production (this is a ’69) they installed two bolts on each side at 90 deg. angles. This was later reduced to 1. I understand the shop that does rebuilds on these install 2 bolts.
Roscoe should have the name of the shop that rebuilds them. I have not heard of an approved field repair of them. -
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