On Sunday, March 7, 2021 at 3:44:34 PM UTC-5, barrflyr wrote:
On Tuesday, March 6, 2018 at 12:46:11 PM UTC-6, Dan Daly wrote:
On Tuesday, March 6, 2018 at 10:55:02 AM UTC-5, Roy B. wrote:
On the subject of Pawnee landing gear - be very careful of the Hutch conversion 2 piece slab type gear that is fixed with 3 vertical bolts. If the centermost bolt fails (as it can from vibration over the years) the gear collapses, the prop strikes the ground, and you have a totaled plane from a situation that really can't be detected/inspected before the failure. We lost a towplane that way in a very light landing on grass when the bolt snapped.
The bungee system has some redundancy and the Cessna one piece gear slab is good - but the 2 piece Hutch gear is a problem.
ROY
The PA-25 SB 25/32/04 dated 01/03/2008 describes a Main Landing Gear Shock Absorption System modification adding a cable to restrict lateral movement of the landing gear leg should a piece of the Hydrasorb shock absorber crack and fail (which they do). We had a Pawnee mod'd (bungee gear system) and had the failure of one support on landing. The down wingtip didn't touch, and neither did the prop. Laviasa had a kit (KIT LA-K-005) with support fittings, a security cable, and longer bolts. Money well spent. I have a soft copy of the SB (2 pages text, 3 pages drawings) if anyone wants one. Also pics of the cable having done its job, a closeup of the installation, and a pic of an unluckier Pawnee without the mod kit.

For light reading, I attach a link to a Canadian Civil Aviation Safety Alert showing the fatigue cracking of the part. https://www.tc.gc.ca/eng/civilaviati...11-02-1344.htm

Dan
Dan
Please send the Laviasa PA-25 SB 25/32/04.
John
Love to, but "reply to author" which allows attachments is not available. If you'd like it, you'll have to send me an e-mail or your e-mail address.

Dan