How did they do that?

[hangarb7]

This was the name of an old television show, but I find myself asking the same question.

My '46 BC12D is annualled, mechanically but not paperworkwise. So, here I am going thru all the log entries looking for AD compliances previous to my inspection. Interesting stories thru out the logs. For example, there are log entries for 1972 at annual, then next page, a sign off annual by the same guy in 1989. Whoa! 17 years? And the airframe time went up by 100 hours?
Pass on thinking about that one...

But early on in N44057's career, there are several annual inspections by different inspectors (or relicense inspections as they called them back then) where they "lifted the airplane to check the gear..." So, what's the procedure and what were they checking? Around 1949, they replaced the main front gear pivot bolts, but no replacement since then. What did they see to need replacement?

Here's another one. Many entries where inspectors checked the wing attach bolts, and in the '60s, they replaced a couple. What were they looking for and what did they see that made replacement necessary?

One last question.... what's the quickest way to get a 337 approved for a new Brackett Airfilter assembly? (assuming I can't fly until I get the paperwork done...)

Thanks for any and all responses,

Jack D.

[Garry Crookham]

Re: How did they do that?

Jack
In my opinion the entries in your logbook indicate the aircraft was receiving quality annual inspections. The airplane was lifted to see if there was any play in the gear at the attach points. That is probably how they found that the gear pivot bolts were worn and needed replacement. Same holds true with the wing attach bolts . Movement was probably detected at the attach points.
The procedure for 337 approval is:
1. A&P installs Brackett air filter assembly, makes logbook entry, and fills out form 337 in duplicate.
2. IA inspects installation and if finds that install conforms to STC,, approves
337.
3. A&P places one copy of 337 in aircraft records and sends other copy to local FSDO.


Garry Crookham
N5112M
Tulsa

[hangarb7]

Re: How did they do that?

Thanks, Garry.

So the 337 is just sent, you don't have to wait for approval, etc.

Back to lifting the TC for inspection of the gear.... how do you do that? Maybe lift one side at a time?

And how do you check for movement in the wing attach bolts? Have someone lift the wingtip while you watch?

Jack

[Robert Lees]

Re: How did they do that?

My understanding is that if you buy the Brackett assembly, it comes with the STC paperwork.

You can lift the gear from the engine mount at the firewall (both legs off the ground), or from the opposite strut/spar fitting (one leg at a time).

Wings: rock fore-and-aft..not up and down. You will hear any knocking that implies loose bolts/elongated holes.

Rob

[Garry Crookham]

Re: How did they do that?

Jack
That is correct...for the Brackett air filter assembly. Brackett has an STC for the air filter assembly (think of it as being pre approved by the FAA) and provides the paper work with the kit. The IA approving the install uses the STC for approved data and can sign it off on the spot....no need to wait for FAA approval. The wording on the 337 should be something like this:
installed Brackett air filter assembly, p/n xxxxxx, rev D, in accordance with STC SA17GL, using Brackett installation instructions p/n yyyyy, dated zz/zz/zz. The FAA considers installing a Brackett air filter assembly a major alteration, and that is why a 337 is necessary.
One point to note..the Brackett filter has instructions for continued airworthiness (ICA) and to be legal the ICA should be complied with (no flames guys, just pointing out a legality that if ignored could void your insurance or cause you to have an appointment with your friendly FSDO airworthiness inspector).
I think Rob answered your questions on how to lift your airplane and on how to check the wing attach bolts/fittings.
Good luck.

Garry