Hey folks, running into a silly one. Wondering if anyone can point me to discussions about this, preferably with either an FAA decision implied...
45.29 talks about N numbering requirements. AC 45-2E gives clarification. By my reading of this (glad for corrections!), a typical fixed wing aircraft needs 12" N numbers these days. As a special case exception, E-ABs that cruise at 180 kts or less (TAS, I assume?) are permitted 3" registration numbers, except that this exception doesn't cover the ADIZ requirement, so if you plan to fly through an ADIZ you still need a (temporary or permanent) 12" N number. This number can be horizontal on the fuse between the wing and h-stab, or on the tail; or as a special exception for E-ABs < 180 kts, can be vertical on the tail, and this exception does apply in the ADIZ case.
Correct reading? Clear as mud?
Let's set aside how to read this for a flying wing with no horizontal stabilizer...
There's one more exception in this, which is 45.29(f), which basically says "try your best by the above rules, and if things still don't fit, use the biggest numbers that do fit." Particularly, this gives an escape hatch of smaller numbers, but doesn't allow an escape hatch of putting the numbers in a different location, or at a diagonal, or anything.
And then 45.29(h) comes in, after that last exception, to give the 12" ADIZ rule.
So... does the (f) exception not apply to the ADIZ rule? That's my basic reading...
But for an aircraft that needs the (f) exception, is there no option to make it ADIZ compliant? Is there a compliant approach to take your N-9M through an ADIZ?
My own case is much closer to the Dyke Delta, and for a while I thought I could just fit compliant 12" numbers on the tail as long as I had a three-digit N number with at least one 1 in it... but after system optimization, it's just not going to fit, and I'm not growing the tail to allow a longer N number!
Ideas?
45.29 talks about N numbering requirements. AC 45-2E gives clarification. By my reading of this (glad for corrections!), a typical fixed wing aircraft needs 12" N numbers these days. As a special case exception, E-ABs that cruise at 180 kts or less (TAS, I assume?) are permitted 3" registration numbers, except that this exception doesn't cover the ADIZ requirement, so if you plan to fly through an ADIZ you still need a (temporary or permanent) 12" N number. This number can be horizontal on the fuse between the wing and h-stab, or on the tail; or as a special exception for E-ABs < 180 kts, can be vertical on the tail, and this exception does apply in the ADIZ case.
Correct reading? Clear as mud?
Let's set aside how to read this for a flying wing with no horizontal stabilizer...
There's one more exception in this, which is 45.29(f), which basically says "try your best by the above rules, and if things still don't fit, use the biggest numbers that do fit." Particularly, this gives an escape hatch of smaller numbers, but doesn't allow an escape hatch of putting the numbers in a different location, or at a diagonal, or anything.
And then 45.29(h) comes in, after that last exception, to give the 12" ADIZ rule.
So... does the (f) exception not apply to the ADIZ rule? That's my basic reading...
But for an aircraft that needs the (f) exception, is there no option to make it ADIZ compliant? Is there a compliant approach to take your N-9M through an ADIZ?
My own case is much closer to the Dyke Delta, and for a while I thought I could just fit compliant 12" numbers on the tail as long as I had a three-digit N number with at least one 1 in it... but after system optimization, it's just not going to fit, and I'm not growing the tail to allow a longer N number!
Ideas?
