337 precedence

D

Donny Hughes

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If an aircraft with the same type certificate as my plane has had a field approval granted with a 337 for a major modification . What if any leg up does that give me to do the same thing to my aircraft ?
 
Depends on the mood of the FSDO the day you ask, especially so if the precedent aircraft had that field approval done at a different FDSO than the one you're attempting to submit work for approval. It's a total crapshoot. I prefer the word sh-tshow but who's counting....100% chance on not getting what you want if you don't ask I suppose, but I prefer to have more solid assurances before I commit AMUs to a major purchase or modification in certified land.

That's why I when they killed primary non-commercial, I forever stopped pining over pipedreams like -540 installations in my arrow or high compression pistons in a pathfinder, and decided to go EAB for my "hopes and dreams". :D
 
Donny Hughes said:
What if any leg up does that give me to do the same thing to my aircraft ?
Click to expand...
Prior to the early 2000s, "duplicate" 337s were widely used. If one like aircraft had a major repair/alteration approved you could extend that approval to other like aircraft administratively through the GADO/FSDO. After about 2002, the "duplicate" 337 went to the wayside and each aircraft required it's own separate field approval. It was also the time the issues of "major change" and STCs came about with certain aircraft alterations. Can you still use a previously approved 337 as part of your data package for a major repair/alteration? Sure. But it is no longer an automatic approval. Your A&P/IA can give you more specific info to your aircraft.
 
I would try.
Make the field approval request.
see what happens.

AC 43-210 is your guide.
The prior Approved 337 is your engineering data
Be certain that this isn't now a STC.
 
Thank Tom .
I had the good fortune of talking with some at my local FSDO that is pro GA .
He was supportive of my proposed mod .
What I am wanting to do was used on Champs and all the mechanical drawing are available from American Champion .

The conversation was very informative and he stated a well planed proposal with good documentation stood a better chance with the engineers who will have to approve the plan .

It was not until about an hour after my conversation with the FAA that one of my feelers yielded an N number that had this mod approved .

Right now until I learn other wise will . My guess I will still have to compile all of the same data and submit for approval with the previously approved 337 as an additional reason to consider my request favorably ?
 
Donny Hughes said:
Right now until I learn other wise will . My guess I will still have to compile all of the same data and submit for approval with the previously approved 337 as an additional reason to consider my request favorably ?
Click to expand...
Actually you should explain in the cover letter that your aircraft will be modified in the same way, using the same engineering.
plus put a statement that the A/C from which the approved 337 was taken, has operated XXX number of hours with this mod installed with no problems.
I would use my PMI at FSDO on a conference call with my A&P-IA to break the ice and discuss what the FAA wants to see.
 
Thanks again Tom that was a very helpful lead to FAA AC 43-210 . It is going to help navigate me through this process . One thing I would like to know is if the previous 337 is public domain and if so how do I attain it . From what I under stand from my first of what I am sure will be many readings of AC 43 is that it would be in my best interest to have all the documents involved in previous 337 so that I can parallel there engineering data so the FAA would be comparing apples to apples .
 
Tom-D said:
Actually you should explain in the cover letter that your aircraft will be modified in the same way, using the same engineering.
plus put a statement that the A/C from which the approved 337 was taken, has operated XXX number of hours with this mod installed with no problems.
I would use my PMI at FSDO on a conference call with my A&P-IA to break the ice and discuss what the FAA wants to see.
Click to expand...
At this point all I have is an N number .
I found the owners name doing a google search an was able get a phone number .
I got an answering machine I am in hopes that he will return my call . I be sure to ask about hours since mod .
Even if I can piggy back previous 337 I will need the approved drawings so I can adhere to them .
 
Bell206 said:
Prior to the early 2000s, "duplicate" 337s were widely used. If one like aircraft had a major repair/alteration approved you could extend that approval to other like aircraft administratively through the GADO/FSDO. After about 2002, the "duplicate" 337 went to the wayside and each aircraft required it's own separate field approval. It was also the time the issues of "major change" and STCs came about with certain aircraft alterations. Can you still use a previously approved 337 as part of your data package for a major repair/alteration? Sure. But it is no longer an automatic approval. Your A&P/IA can give you more specific info to your aircraft.
Click to expand...
I have always been a day late an a dollar short .
 
Well it looks like this is all over . I got info from the DAR/test pilot at American Champion they are now on Type Certificate
 
Donny Hughes said:
At this point all I have is an N number .
I found the owners name doing a google search an was able get a phone number .
I got an answering machine I am in hopes that he will return my call . I be sure to ask about hours since mod .
Even if I can piggy back previous 337 I will need the approved drawings so I can adhere to them .
Click to expand...
pay the $10 and get a copy of his 337's from the FAA....
 
I don't know if any of this helps now. here's a link to a Champion 7CCM with some photos of a landing light in the LE. The N number is N83964.
http://airplanesusa.com/?planes=aeronca-champ

Looking at my copy of Aeronca factory drawings, Here's one showing a Grimes light mounted on the bottom of the wing and folding out and forward. The drawings are number 4-889 and 4-888.
 
Donny Hughes said:
Well it looks like this is all over . I got info from the DAR/test pilot at American Champion they are now on Type Certificate
Click to expand...
Then all you need is a major alteration to retro-fit the light to your model.
 
Donny Hughes said:
Well it looks like this is all over . I got info from the DAR/test pilot at American Champion they are now on Type Certificate
Click to expand...
Amazing what you can find if you talk to the right person ...I ran across a guy one time whose company had already spent tens of thousands of dollars trying to get a gross weight increase on their older Hawker. I happened to have a copy of the factory service bulletin in my bag that we were in process of applying to our airplane that gave more than twice the increase that they were trying to engineer.
 
Donny Hughes said:
At this point all I have is an N number .
I found the owners name doing a google search an was able get a phone number .
I got an answering machine I am in hopes that he will return my call . I be sure to ask about hours since mod .
Even if I can piggy back previous 337 I will need the approved drawings so I can adhere to them .
Click to expand...

The N number, and $10 to OKC will get you a CD with all the records on file with the FAA for that particular aircraft. Including, (but not limited to) leins, 337s, and registration changes.
 
bluerooster said:
The N number, and $10 to OKC will get you a CD with all the records on file with the FAA for that particular aircraft. Including, (but not limited to) leins, 337s, and registration changes.
Click to expand...
thank you....thought no one would think of that. ;)
 
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