Tail Post Damage

[clear_prop1961]

This past Saturday I flew in to the Hollister Airshow (10 miles from home base) and after taxiing over to the display area and shutting down the engine and moving the aircraft to where they wanted it... when they wanted me to move it back 10 feet the tail wheel chocked over to one side. Inspection showed that the front bolt that holds the spring to the fuselage was broken though. More inspection after removing some fabric showed tail post and lower longeron damage as well as the plate that attaches the front bolt for the spring.
I have now cut out the damaged tail post part and here are a few photos. I will do the repairs per AC43.13 but I would like to know more infor on the plate or U bracket that the front bolt attaches too. What thickness is it? .062"?

Well the aircraft is 73 years old so I guess one can expect some tail post corrosion. The good news is that the aircraft did not get more damaged on landing and that it happened only a few miles from home base. The other good news is the aircraft won best antique aircraft. As you can see I'm trying to look on the bright side..... it could have been much worse.
Jerry

[astjp2]

Re: Tail Post Damage

Those 3 dimples are a pain in the butt to put into steel that thick, its possible for a field repair but still a pain...Tim

[Hank Jarrett]

Re: Tail Post Damage

Jerry, Sent you an email with phone number. I have the tail at home in our sun room and can give you any measurements you need. Let me know when you want to connect up.
Hank

[N96337]

Re: Tail Post Damage

Personally, I'd be cutting a ways further than you have there. If it's that bad there, chances are that it's not that great for a ways away either. I like to use my "borescope" and go as far away from the problem as I can to make sure. I found spots on the lower longerons of a Bellanca that were just droplett sized and a few inches apart, all the way from the front to the back... I also like to do the splices a ways away, so there's more "working" room. Just my opinion.
John

PS...glad you found it the way you did!!

[clear_prop1961]

Re: Tail Post Damage

John, I did check the lower longerons and they look ok, I'm relieved to say. I cleaned the tubes with a wire bottle brush back in about 12 to 15" and looked inside. I also tapped on the longerons with a hammer. I have now made the splices in the tail post and longerons and ground out the material where the front bolt goes. From photos that Hank has send me of a 1946 tail section I can see that my 1941 model is different for the bolt attachment so I'll have to a change here. So now I have to make the parts to splice in.

The 3 dimples look to me to be the bucked end of rivets. I plan to use steel rivets for this. I'll post more photos in a day or so.
Jerry

[lfries]

Re: Tail Post Damage

I have added an item to my preflight. Yesterday helping removes wings on a Luscombe found another item to be more careful about. The lower rudder bracket had come lose from the bulkhead. . Lots of side mvmt. Thanks for sharing.

[N96337]

Re: Tail Post Damage

John, I did check the lower longerons and they look ok, I'm relieved to say. I cleaned the tubes with a wire bottle brush back in about 12 to 15" and looked inside. I also tapped on the longerons with a hammer..
Jerry

Good deal! It's tough not to come across as being a jerk about it, and I certainly wasn't trying to be...just want everyone safe. Sounds like it's all under control!

[clear_prop1961]

Re: Tail Post Damage

Well here is an up-date on the tail post repair. I decided to weld in a tube 3/4" high (3/4" dia.) for the front 3/8" bolt which I made from 4130 1" bar stock. I also made a fixture to hold the tube in place for welding. I spliced the lower longerons a few inches behind the rear cluster and fab the inner splice tubes from thick wall 3/4"od tubing (.095 wall) and machined them down to .670 od so they are .010 under size for a good fit per the request of my IA. The inner splice tube is 9 1/2" long and go from the tail post to in front of the rear cluster. The tail post inner splice goes down to the base of the post. I made the inner splice tubes go to the tail post to reinforce this area. I did not make a photo of the rear foot/plate with the two bolt holes but it is ready to weld in also. I'm now ready to weld ready thing.

More later,
Jerry

[woodmw]

Re: Tail Post Damage

Jerry,

Quality workmanship, IMHO.... Did you have to ream/file to get the inner splice tubes to pass through the rear cluster welds? Just curious if any of these welds penetrated thru the longerons. Could you post a picture showing how much fabric you removed to do this repair?

Thanks

[clear_prop1961]

Re: Tail Post Damage

Mike- Yes I did have to file the cluster welds some. I also removed another .010" on the dia. of the inner splice tubes in the area where it goes thur the cluster.... that did the trick. This photo gives you an idea about removing the fabric... I covered the area with alum foil in case sparks jump. I also covered the bottom of the horz. stabilizers. I plan to add heat sink material around the tubing before welding also.
Hope this helps.
Jerry

[Scott]

Re: Tail Post Damage

could also wrap the tubes with cloth (wool) and keep it wet during and after welding to help reduce the heat conducting up the tubes and damaging fabric.

[clear_prop1961]

Re: Tail Post Damage

Here is another up-date on the tail post repair. Yesterday my welder welded the repair joints and today I epoxy primed the tubing. Tomorrow we'll start on the fabric repair. Here are a few photos. Note the jig for positioning the rear bracket for welding. Also note the raised spots on the bottom of bracket was done by welding a bead and flattening them on the belt sander
Jerry

[mike lutz]

Re: Tail Post Damage

Nice looking job.

[Hank Jarrett]

Re: Tail Post Damage

Have you talked to your IA about maybe metalizing the "Terrible Taylorcraft Triangle"? I plan to do that on my next recover so the tail can be opened up on annual for inspection and removal of all the JUNK that seems to migrate back there.

Hank

[clear_prop1961]

Re: Tail Post Damage

Here are more photos. Jerry