Backcountry Pilot • STC Development

STC Development

Have problems with your aircraft? Maybe just questions about how best to tune or adjust something? Regs or maintenance? Need to know the best way to do something?
16 postsPage 1 of 1

STC Development

Does anyone on here have experience developing STCs? I'm a young engineer and motivated, just don't know where to start. Not a lot of info available online.
hamer offline
User avatar
Posts: 231
Joined: Tue Sep 25, 2018 10:30 pm
Location: Huntington Beach

Re: STC Development

There’s a bunch of info online. The FAA even has a manual that gives step by step instructions.

When I was a young and motivated engineer I wanted to get an STC, several actually. I went through the manual, talked to the FSDO and then a DER. That’s when I learned the DER would cost me so much money that I’d likely never break even on my particular STC. Hopefully you have a better, more profitable idea than mine was.

Good luck!
whee offline
User avatar
Posts: 3386
Joined: Fri Jan 20, 2006 1:59 pm
Location: SE Idaho

Re: STC Development

whee wrote:There’s a bunch of info online. The FAA even has a manual that gives step by step instructions.

When I was a young and motivated engineer I wanted to get an STC, several actually. I went through the manual, talked to the FSDO and then a DER. That’s when I learned the DER would cost me so much money that I’d likely never break even on my particular STC. Hopefully you have a better, more profitable idea than mine was.

Good luck!


How does one become a DER? I've known a few but never inquired how they got the designation.
Zzz offline
Janitorial Staff
User avatar
Posts: 2854
Joined: Fri Oct 08, 2004 11:09 pm
Location: northern
Aircraft: Swiveling desk chair
Half a century spent proving “it is better to be thought a fool than to open your mouth and remove all doubt.”

Re: STC Development

Zzz wrote:
whee wrote:There’s a bunch of info online. The FAA even has a manual that gives step by step instructions.

When I was a young and motivated engineer I wanted to get an STC, several actually. I went through the manual, talked to the FSDO and then a DER. That’s when I learned the DER would cost me so much money that I’d likely never break even on my particular STC. Hopefully you have a better, more profitable idea than mine was.

Good luck!


How does one become a DER? I've known a few but never inquired how they got the designation.


https://www.faa.gov/other_visit/aviation_industry/designees_delegations/individual_designees/der/become/

DAR's are a whole different matter.. I started the application since I am a DMIR for my company, just haven't finished it yet.. Really not sure I want that responsibility.

STC development can be hard or easy, just depends on what you are trying to do. I have abandoned several so far because of development cost versus potential sales. It gets to the point where you are just throwing money down the drain.

Brian
Brian-StevesAircraft offline
KB and Supporter
User avatar
Posts: 759
Joined: Tue Dec 13, 2005 1:13 pm
Location: Beagle (White City) Oregon
Pavement scares me..........

Dad's SPOT page

Re: STC Development

whee wrote:There’s a bunch of info online. The FAA even has a manual that gives step by step instructions.

When I was a young and motivated engineer I wanted to get an STC, several actually. I went through the manual, talked to the FSDO and then a DER. That’s when I learned the DER would cost me so much money that I’d likely never break even on my particular STC. Hopefully you have a better, more profitable idea than mine was.

Good luck!


Yea, like most FAA manuals that one isn't entirely useful. Was hoping someone has successfully been through the process and willing to share some tips. Seems like everywhere I turn people just say it isn't worth it.
hamer offline
User avatar
Posts: 231
Joined: Tue Sep 25, 2018 10:30 pm
Location: Huntington Beach

Re: STC Development

We’ll have disagree there. I thought the manual was good and provided all the info I needed. I knew what design details were required and what paperwork needed filled out. The FSDO thought the design was good and all the paperwork was correct. I did it all without any guidence other than the manual and a couple emails to the FSDO. The FSDO guy was almost as disappointed as I was when the DER told me how much it would cost to review and stamp the analysis I proved him.
whee offline
User avatar
Posts: 3386
Joined: Fri Jan 20, 2006 1:59 pm
Location: SE Idaho

Re: STC Development

whee wrote:We’ll have disagree there. I thought the manual was good and provided all the info I needed. I knew what design details were required and what paperwork needed filled out. The FSDO thought the design was good and all the paperwork was correct. I did it all without any guidence other than the manual and a couple emails to the FSDO. The FSDO guy was almost as disappointed as I was when the DER told me how much it would cost to review and stamp the analysis I proved him.


I think you just have a friendlier FSDO. I'm still waiting on a response from almost 2 years ago from my FSDO, have emailed and called multiple times. I saw "FSDO" and balled up lol.
hamer offline
User avatar
Posts: 231
Joined: Tue Sep 25, 2018 10:30 pm
Location: Huntington Beach

Re: STC Development

I know a guy who developed a replacement cowl for the Grumman 4-seat AA-5/5A/5B line. The entire effort cost him well over $500,000 about 10 years ago. The new cowl makes the plane about 8 knots faster, and cools the O-360 engine MUCH better than the factory cowl. He thought the entire fleet would beat a path to his door, since the Grumman Cheetah/Tiger line is all about "speed"... So far, he's sold maybe 20 of them... And lost about -$495,000 in the process... Tough gig!

The irony to me is that his cowl with the STC costs less than the PMA'ed cowls that you have to wait 6 months to get from the current TC holder, and only slightly more than the salvage cowls available from aircraft boneyards... We pilots are a cheapskates!
JP256 offline
Supporter
User avatar
Posts: 629
Joined: Mon Aug 31, 2015 1:52 pm
Location: Cedar Park
Aircraft: Rans S-6ES

Re: STC Development

Yikes. I would have guessed $5-10k for something like that, but not $500k. Sounds like the same issue everywhere else in GA, bloated bureaucracy pricing out the regular guy.

None of my ideas are money makers. I just like to design and make things and I figured I could help keep GA moving forward.
hamer offline
User avatar
Posts: 231
Joined: Tue Sep 25, 2018 10:30 pm
Location: Huntington Beach

Re: STC Development

hamer wrote:
whee wrote:We’ll have disagree there. I thought the manual was good and provided all the info I needed. I knew what design details were required and what paperwork needed filled out. The FSDO thought the design was good and all the paperwork was correct. I did it all without any guidence other than the manual and a couple emails to the FSDO. The FSDO guy was almost as disappointed as I was when the DER told me how much it would cost to review and stamp the analysis I proved him.


I think you just have a friendlier FSDO. I'm still waiting on a response from almost 2 years ago from my FSDO, have emailed and called multiple times. I saw "FSDO" and balled up lol.


Probly so.
whee offline
User avatar
Posts: 3386
Joined: Fri Jan 20, 2006 1:59 pm
Location: SE Idaho

Re: STC Development

hamer wrote:Yikes. I would have guessed $5-10k for something like that, but not $500k. Sounds like the same issue everywhere else in GA, bloated bureaucracy pricing out the regular guy.

None of my ideas are money makers. I just like to design and make things and I figured I could help keep GA moving forward.

Part of the issue with his cowling was that there are actually three different models in that group, and the FAA required flight testing on all three models. Very detailed flight testing. It was ridiculous, because the only real difference is that the -5 and -5A have O-320s, whereas the -5B uses an O-360. But the new cowling affected not just cooling air, but required new baffling, different air intake (therefore different filtration) and a bunch of other small changes that just kept adding up. By the time he realized what it would cost to finish up the flight testing, he was already in so deep that it just didn't matter.

What's that old saying? Oh yeah: "If you want to make a small fortune in aviation, start with a large fortune!"
JP256 offline
Supporter
User avatar
Posts: 629
Joined: Mon Aug 31, 2015 1:52 pm
Location: Cedar Park
Aircraft: Rans S-6ES

Re: STC Development

JP256 wrote:
hamer wrote:Yikes. I would have guessed $5-10k for something like that, but not $500k. Sounds like the same issue everywhere else in GA, bloated bureaucracy pricing out the regular guy.

None of my ideas are money makers. I just like to design and make things and I figured I could help keep GA moving forward.

Part of the issue with his cowling was that there are actually three different models in that group, and the FAA required flight testing on all three models. Very detailed flight testing. It was ridiculous, because the only real difference is that the -5 and -5A have O-320s, whereas the -5B uses an O-360. But the new cowling affected not just cooling air, but required new baffling, different air intake (therefore different filtration) and a bunch of other small changes that just kept adding up. By the time he realized what it would cost to finish up the flight testing, he was already in so deep that it just didn't matter.

What's that old saying? Oh yeah: "If you want to make a small fortune in aviation, start with a large fortune!"


So did the flight testing have to be done by a specifically qualified person? Or could he have done the flight testing on his own to save a few dollars?
hamer offline
User avatar
Posts: 231
Joined: Tue Sep 25, 2018 10:30 pm
Location: Huntington Beach

Re: STC Development

hamer wrote:
JP256 wrote:
hamer wrote:Yikes. I would have guessed $5-10k for something like that, but not $500k. Sounds like the same issue everywhere else in GA, bloated bureaucracy pricing out the regular guy.

None of my ideas are money makers. I just like to design and make things and I figured I could help keep GA moving forward.

Part of the issue with his cowling was that there are actually three different models in that group, and the FAA required flight testing on all three models. Very detailed flight testing. It was ridiculous, because the only real difference is that the -5 and -5A have O-320s, whereas the -5B uses an O-360. But the new cowling affected not just cooling air, but required new baffling, different air intake (therefore different filtration) and a bunch of other small changes that just kept adding up. By the time he realized what it would cost to finish up the flight testing, he was already in so deep that it just didn't matter.

What's that old saying? Oh yeah: "If you want to make a small fortune in aviation, start with a large fortune!"


So did the flight testing have to be done by a specifically qualified person? Or could he have done the flight testing on his own to save a few dollars?


Unless something has changed in the last 10 years, flight testing is by an FAA representative. At least that what happened when we certified the 0-360 A1P with a constant speed prop on the Pacer. That's another one of those STC's that has not sold enough to brake even on the development costs.

I do not have time today but give me a call sometime next week and I can try to lead you down the right path.

Brian.
Brian-StevesAircraft offline
KB and Supporter
User avatar
Posts: 759
Joined: Tue Dec 13, 2005 1:13 pm
Location: Beagle (White City) Oregon
Pavement scares me..........

Dad's SPOT page

Re: STC Development

Yep - what Brian said... FAA rep had to be in the plane for all the flights.
JP256 offline
Supporter
User avatar
Posts: 629
Joined: Mon Aug 31, 2015 1:52 pm
Location: Cedar Park
Aircraft: Rans S-6ES

Re: STC Development

But you get your name in lights, and you're an overnight celebrity as well as millionaire!!!! :D Yeah....well, maybe not quite. Like said above, the DER is money....lots of it....and on their own schedule. I'd LOVE to break even on my STC, but in reality, I don't foresee that ever happening.
John
hardtailjohn offline
User avatar
Posts: 924
Joined: Thu Mar 16, 2006 7:06 pm
Location: Marion, Montana
God put me here to accomplish a certain amount of things...right now I'm so far behind, I'll never die!!

Re: STC Development

My dad did our pod STC back in the early 90s. We did the inspection panel kit together and got approved in 2017. I can talk about the process if you want.

It's cumbersome and frustrating, and I think that's deliberate. They don't want to review a bunch of justification for an STC that will sell 5 copies, which is ridiculous. It's not their job to determine the marketability of a mod, just the airworthiness of the idea. We spent 4 years on the inspection panel STC, but to be fair, 3 of them were with an engineer that acted like we were working on the space shuttle. Find a good engineer, preferably an ODA, and it's all dependent on your idea. Simple changes are simple if you can sell them on it, complex changes are dependent on what you can sell them on.

I'm happy to talk about it if you want to PM me.
AEROPOD offline
Posts: 479
Joined: Sun Jul 22, 2012 11:02 pm
Location: Aurora, CO

DISPLAY OPTIONS

16 postsPage 1 of 1

Who is online

Users browsing this forum: No registered users and 0 guests

Latest Features

Latest Knowledge Base