Why Not? I've been thinking about making my own instead of buying two panels for $700. The bulkhead closeout would be very simple to make. The floor may be a little trickier but certainly doable. The down side would be the approval basis. Have any of you guys went down this road?

Jered, I would expect this to fall firmly into the major alteration realm, despite how simple it may be.

FYI there are going to be a lot of people on here that will recite the FARs and tell you how bad of an idea it is, but in reality I would work with your IA on it and make it removable if you ever decide to sell it.

Well aware of the legality side of it but that doesn't mean it cant be done. I am my own IA

The FAA. Has policy which prohibits them from field approving anything that is already STCd.

So, you planning on getting your own STC?

MTV

mtv wrote:The FAA. Has policy which prohibits them from field approving anything that is already STCd.

So, you planning on getting your own STC?

MTV

I was not aware of that policy. Plan was field approval.

The two faa inspectors I've talked to said the same thing; if an STC exists then no field approval unless you can prove the STC is no longer supported.

Thats good to know. I guess that kind of kills my idea.

Not necessarily. Who produces an STC'd extended baggage? I think Selkirk does, don't know who else. What aircraft is it STCd for? If the 180/182 but not the 172, you're not trying to field-approve an already-STC'd mod. It also seems to me that if you configure your home-made extended baggage differenty in some way, in other words not copy the STC'd unit, you have a different item- and so again are not trying to field-approve an STC'd item.
I've seen people get field approvals for an odyssey battery on the firewall, when Dodge and others have an STC for a similar installation. The key word here is similar. I believe Bill Reid/182 STOL makes & sells a firewall battery set-up that is a field approval item.

Selkirk is STC'd for 180/182 and 172s. Airglas also has an STC'd extended baggage for 180/182/185s.

The STC'd kit I had was only 50% useful. I had to throw out the aluminum bits provided and fab my own because they didn't come close to fitting. I also had to throw out the battery box cover and fab my own. I had to do major surgery on the floor panel to make it fit. I think it was the fact my year model was an odd ball, because others installed kits easily from the same manufacturer, but if I had done it all myself from scratch I would have saved some time and a lot of money.

I'd look into it. Perhaps by adding a fishing pole tube or something substantively different from what the STC kits offer, you could go for a 337.

Being that you are an IA you must have some relationship with an inspector at the FSDO. It is worth a call to see what they say. When I was trying to put hydraulic brakes on the Luscombe I had I developed a relationship with the guy at the FSDO. I told him that there was an STC available to do the install but the STC holder only randomly supported it and when they did the paperwork alone cost $4K. He agreed that it was ridiculous and began the process to get a field approval. If I remember correctly he did tell me I couldn't copy the STC install exactly, something had to be different.

It can be done. We did it on my 170B and had it field approved just last spring. Not a simple process by any means, they put us through a lot of hoops such as a flight supplement like you find in later Cessnas showing the position of the extended baggage area and it CG station so you can accurately calculate a weight and balance. You'll also need proper tie down points for securing baggage. Other than that it just took tenacity and patience.

Bryan

I'm looking at needing to go this route before. Luckily I've got copies of 337s and successful installs so we won't be reinventing the wheel so to speak. No STC for the 205.

Remember that discussion about PNC category. Sure would eliminate a lot of the BS with the FAA and over priced STCs!

whee wrote: Being that you are an IA you must have some relationship with an inspector at the FSDO. It is worth a call to see what they say. ......

I agree, talk to your PMI about it. I think a lot of those guys are pretty reasonable, esp those with a GA mechanic background.
Grrass Strip Pilot, what's a PNC category?

There's also the DER route.

Seems like an awful lot of time and trouble to do something that's already been done. Why re-invent the wheel???

Not for nuthin... but the kit I installed from Hitchcock was the cats meow. At only 4ish lbs, it was not only light as hell, but the carbon fiber is super strong. No muss no fuss. Fit perfect out of the box and was worth every penny.

I agree with Bigrenna. I also agree that you may be able to work something out with your PMI by changing the design, though I think you'll have to come up with some change that's actually significant.

The reason for this policy to not field approve modifications that already are STCd is that manufacturers spend thousands of dollars or more and hundreds of hours of their time to create and get a mod approved with an STC. So, then every Joe Blow comes along, copies what these folks spent time and money to get approved, and submit for a field approval. If you don't believe that, you should have spent some quality time listening to Atlee Dodge "discussing" that subject. It's the reason he quit working toward STC's for many of his products.

Eventually, the FAA agreed that to field approve something that is essentially a knock off of a product that someone else spent a lot of money and engineering on to get approved should not be permitted. And, I thoroughly agree.

I would discuss with your PMI and see what he/she says. But, my experience with field approvals is that they can take a looooong time to get approved. Bear in mind also that all field approvals now must go through a committee process in the FSDO, so it isn't strictly up to one Inspector.

As Bigrenna says, it makes little sense to re-invent the wheel, when a couple of good products are out there. Since you're an IA, you can use the time you'd spend thrashing around with this to work on customer's airplanes, and let them pay for your baggage compartment....

MTV

Good points guys. The reason for doing it myself and 'reinventing the wheel' is simply because I like doing things for myself. I enjoy fabricating and would like to do it my way and possibly include a fishing pole/rifle tube and who knows what else. Is it worth the trouble??? Maybe not.

bigrenna wrote:Seems like an awful lot of time and trouble to do something that's already been done. Why re-invent the wheel???

Not for nuthin... but the kit I installed from Hitchcock was the cats meow. At only 4ish lbs, it was not only light as hell, but the carbon fiber is super strong. No muss no fuss. Fit perfect out of the box and was worth every penny.

It would be nice if that kit was approved for the 170/172. I would have choose it over the Selkirk for the weight savings alone, not to mention the fit/finish. It's about 6lbs lighter than the Selkirk.