how is 51% compliance determined by FAA?

[Ernie]

I'm trying to understand what a legal kit is. Does a kit supplier use a Designee of some sort, or own judgement and hope for the best, or supply a kit to the FAA, or What?

[rwanttaja]

I'm trying to understand what a legal kit is. Does a kit supplier use a Designee of some sort, or own judgement and hope for the best, or supply a kit to the FAA, or What?

Here's the checklist the FAA uses to determine if an airplane built from a kit qualifies under the 51% rule:

https://www.faa.gov/sites/faa.gov/files/aircraft/gen_av/ultralights/amateur_built/Am_Blt_Chklist_Job_Aid.pdf

Here's the list of kits the FAA found eligible under the 51% rule.

https://www.faa.gov/aircraft/gen_av/ultralights/amateur_built/kits/amateur_built_kit_listing

Finally, here's the Advisory Circular covering certification of amateur-built aircraft:

https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_20-27G.pdf

Ron Wanttaja

[Ernie]

Thanks!

[CHICAGORANDY]

Kinda shows why there are so many RVs at AirVenture every year -lol