Major portion

[Eric Brown]

I've been in the small airplane business a long time. Now I am thinking of building my first experimental airplane. Trouble is, I'm thinking of starting with a junked out Cessna 150. No records, no data plate. I've been thru FAR 21.191(g), AC20-27G section 8(d)(1)(2), and FAA Order 8130.2J chptr 15-2(f). This process seems to be discouraged. I would be making a mini Cessna L-19. Major fuselage, cowl, landing gear, and tail redesign.
What would be the odds of getting this accepted by the FAA ?

[rwanttaja]

I've been in the small airplane business a long time. Now I am thinking of building my first experimental airplane. Trouble is, I'm thinking of starting with a junked out Cessna 150. No records, no data plate. I've been thru FAR 21.191(g), AC20-27G section 8(d)(1)(2), and FAA Order 8130.2J chptr 15-2(f). This process seems to be discouraged. I would be making a mini Cessna L-19. Major fuselage, cowl, landing gear, and tail redesign.
What would be the odds of getting this accepted by the FAA ?
Probably pretty good, *if* it's a brand-new fuselage design. The FAA has been good with re-using wings for a long time.

Your odds are better if the fuselage is distinctly different from a standard 150. A good example is the "Defunky Cub," the V-6 STOL. You start with a stock Piper fuselage, and extend it (among other things). If your L-19/150 is tandem seating, I don't really see a problem.

Ron Wanttaja

[Joda]

The current guidance as well as the general atmosphere around FAA aircraft certification offices strongly discourage using salvaged components from previously-certificated airframes in the construction of a new amateur-built aircraft. Most FAA inspectors I have talked to consider ANY work done on pre-existing components to be "repair" that will not count toward the major portion requirement. This includes major modification to the components. It would be VERY difficult to get an aircraft such as you describe certificated as amateur-built under the current certification guidance. You may be able to get it certificated in experimental-exhibition category, but amateur-built is going to be a stretch.

I would suggest you talk to the FAA inspector or DAR in your area about the project BEFORE you spend any time or money working on it. If they think it will work, get their opinions IN WRITING, with as much detail as possible. You wouldn't want to get a verbal OK from an inspector, only to have that inspector retire or move to another office and have the next person have a completely different analysis of your project.

[Eric Brown]

Probably pretty good, *if* it's a brand-new fuselage design. The FAA has been good with re-using wings for a long time.

Your odds are better if the fuselage is distinctly different from a standard 150. A good example is the "Defunky Cub," the V-6 STOL. You start with a stock Piper fuselage, and extend it (among other things). If your L-19/150 is tandem seating, I don't really see a problem.

Ron Wanttaja


The fuselage would be narrowed toward the bottom and changed to tandem seating.

[Frank Giger]

WacoJoe has the heart of it.

While I usually go along with the "beg forgiveness rather than permission" theory of doing things, in this case I'd have a sit down with the local FDSO and talk about it.

From my discussions with our FAA guy, if you take it down to zero, rebuild and re-fabricate parts, it's okay. Plus it's only one part of the process - there's a whole checklist that determines if something is 51% or not.

[martymayes]

I've been in the small airplane business a long time. Now I am thinking of building my first experimental airplane. Trouble is, I'm thinking of starting with a junked out Cessna 150. What would be the odds of getting this accepted by the FAA ?

You can certainly build an experimental airplane the way you describe and the FAA will accept what you did but the plane might not pass the sniff test for
experimental, amateur-built which is probably what you are shooting for.