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N Number Placement/Orientation

D

Dave S

Active Member
I'm getting lost on the orientation of the N Number.

AC-45-2E Table 2, states that Experimental Amateur Built aircraft with a cruise speed of less than 180kts with have the orientation of the N Number as "Horizontal(with exemptions as shown in table 3)

Table 3 states that 'Displaying a minimum-height N-number on exhibition, amateur-built, or light-sport aircraft with a maximum cruising speed of 180 knots or less'
(2) If you display N-numbers vertically, follow the requirements of § 45.25(b)(1), Location of marks on fixed-wing aircraft.

42.25(b)(1) states If displayed on the vertical tail surfaces, horizontally on both surfaces, horizontally on both surfaces of a single vertical tail or on the outer surfaces of a multivertical tail. However, on aircraft on which marks at least 3 inches high may be displayed in accordance with § 45.29(b)(1), the marks may be displayed vertically on the vertical tail surfaces.

Does that mean that on an RV-7 you can display 3 inch N number vertically on the tail, or does (2) from table 3, refers back to (1) which cites 30 year old aircraft.
 
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Dave S said:
I'm getting lost on the orientation of the N Number.

AC-45-2E Table 2, states that Experimental Amateur Built aircraft with a cruise speed of less than 180kts with have the orientation of the N Number as "Horizontal(with exemptions as shown in table 3)

Table 3 states that 'Displaying a minimum-height N-number on exhibition, amateur-built, or light-sport aircraft with a maximum cruising speed of 180 knots or less'
(2) If you display N-numbers vertically, follow the requirements of § 45.25(b)(1), Location of marks on fixed-wing aircraft.

42.25(b)(1) states If displayed on the vertical tail surfaces, horizontally on both surfaces, horizontally on both surfaces of a single vertical tail or on the outer surfaces of a multivertical tail. However, on aircraft on which marks at least 3 inches high may be displayed in accordance with § 45.29(b)(1), the marks may be displayed vertically on the vertical tail surfaces.

Does that mean that on an RV-7 you can display 3 inch N number vertically on the tail, or does (2) from table 3, refers back to (1) which cites 30 year old aircraft.
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That is the way I read it. If you are going to use paint, confirm first......:D
 
What they are trying to say is that when displayed on the vertical surfaces, 3" numbers may be placed one above the other but you cannot rotate the "number set" vertically.

In other words you cannot place the number set so that one would need to turn his/her head to read.
 
some drift...

I'm thinking that numbers larger than 3" but smaller than 12" on the fuselage sides might look best on my paint scheme. I realize this won't pass muster with Customs for entering the CONUS ADIZ. Is there any other reason say 8" numbers wouldn't serve just as we'll as the standard 3-inchers we typically use?
 
Bill Boyd said:
I'm thinking that numbers larger than 3" but smaller than 12" on the fuselage sides might look best on my paint scheme. I realize this won't pass muster with Customs for entering the CONUS ADIZ. Is there any other reason say 8" numbers wouldn't serve just as we'll as the standard 3-inchers we typically use?
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Number size requirements are minimum sizes. You may always use larger numbers.
 
Mel said:
What they are trying to say is that when displayed on the vertical surfaces, 3" numbers may be placed one above the other but you cannot rotate the "number set" vertically.

In other words you cannot place the number set so that one would need to turn his/her head to read.
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Meaning that my still in construction RV-7 could have the numbers on the tail;

N
7
4
7
X
S
 
Thank you Mel and David, I appreciate the clarifications!

Not sure how I missed the home builders week seminar, I always look and this is perfect timing.
 
N-number display

Recently I ran across a plane with the 3" N-numbers on the tail in a diagonal with the N down to the left running up the forward edge of the stabilizer. I told the owner I wasn't sure that was a legal way to display an N-number.

He said, basically, people tell him that but until the FAA does he isn't going to change it.

Any thoughts on if this is a legal way to display an N-number?
 
RRHall said:
Recently I ran across a plane with the 3" N-numbers on the tail in a diagonal with the N down to the left running up the forward edge of the stabilizer. I told the owner I wasn't sure that was a legal way to display an N-number.

He said, basically, people tell him that but until the FAA does he isn't going to change it.

Any thoughts on if this is a legal way to display an N-number?
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14 CFR 45.25 specifically uses the word "Horizontal" (with the exceptions for "Vertical" as noted in this thread). Nowhere does the word "diagonal" appear. (My old welding instructor used to call this "vertizontal" :) ) I have seen a few aircraft with N numbers displayed as you describe, and I (along with my FAA office) say "no", such does not meet the regulation.
 
RRHall said:
Recently I ran across a plane with the 3" N-numbers on the tail in a diagonal with the N down to the left running up the forward edge of the stabilizer. I told the owner I wasn't sure that was a legal way to display an N-number.

He said, basically, people tell him that but until the FAA does he isn't going to change it.

Any thoughts on if this is a legal way to display an N-number?
Click to expand...

A good rule to go by....... Only break one law at a time....

If the FAA is out ramp checking, this may just be all he needs to draw his attention.
 
There’s Legal and Then

RRHall’s story is not uncommon. I’ve seen a few instances where folks put markings on airplanes that blatantly flout the rules. 2” numbers tucked under the horizontal stabilizer, letters and numbers in colors that are not contrasting, characters that were so stylized they were all but unreadable. We had an airplane the airport that flew for months with no tail number at all. A Fed finally wandered by and told the owner to please put the number on. The guy wrote it on the vertical with a Magic Marker. It was crude but stayed like that for a very long time. Point is, while of course markings should be in accordance with rules and regulations, it doesn’t seem to be rigorously enforced.
 
Another thing about N numbers that I don’t think has been discussed in this post is the use of the letter X as the leading letter in your N number. In other words: XN286HS vs N286HS. If you register with a leading X on an experimental airplane, then you don’t have to have the EXPERIMENTAL placard anywhere on the airplane. At least that’s the way I read it, and the way it was explained to me. I didn’t do it that way because I had already registered my N number and didn’t want to go through the paper work to change it.
 
A Little Clarification.......

Scott Hersha said:
Another thing about N numbers that I don’t think has been discussed in this post is the use of the letter X as the leading letter in your N number. In other words: XN286HS vs N286HS. If you register with a leading X on an experimental airplane, then you don’t have to have the EXPERIMENTAL placard anywhere on the airplane. At least that’s the way I read it, and the way it was explained to me. I didn’t do it that way because I had already registered my N number and didn’t want to go through the paper work to change it.
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The "X" when used within the "N" number is NOT within the registration! It is NOT used in communication or anywhere else. The "X" simply replaced the "EXPERIMENTAL" placard on experimental aircraft more than 30 years old or an experimental replica of an aircraft more than 30 years old.

And BTW, the "X" comes after the "N", not before (NX286HS). And the same FAR allows for a minimum size of 2" on these aircraft. ref: Part 45.22(b)
 
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Mel said:
The "X" when used within the "N" number is NOT within the registration! It is NOT used in communication or anywhere else. The "X" simply replaced the "EXPERIMENTAL" placard on experimental aircraft more than 30 years old or an experimental replica of an aircraft more than 30 years old.

And BTW, the "X" comes after the "N", not before (NX286HS). And the same FAR allows for a minimum size of 2" on these aircraft. ref: Part 45.22(b)
Click to expand...

This is very timely for me because I just saw a few planes with NX... this weekend at the STOL competitions.

I don't plan to change any decals but just to expand my knowledge, for my 1969 N52VM:

I can legally just replace the registration on my plane (without telling the FAA) with NX52VM & remove the EXPERIMENTAL sticker?
Then when talking with ATC just say N52VM ?
 
Mel said:
The "X" when used within the "N" number is NOT within the registration! It is NOT used in communication or anywhere else. The "X" simply replaced the "EXPERIMENTAL" placard on experimental aircraft more than 30 years old or an experimental replica of an aircraft more than 30 years old.

And BTW, the "X" comes after the "N", not before (NX286HS). And the same FAR allows for a minimum size of 2" on these aircraft. ref: Part 45.22(b)
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Thanks for the clarification Mel….. I guess my memory has been found “wanting”. Good thing I didn’t try to go that direction (wouldn’t have worked). My friend that told me about this, and showed me in the Regs - which I clearly didn’t read very thoroughly - has a Bucker Jungman replica, so maybe that works for him. I still think it’s interesting that was an option at one time.
 
N-number prefix

It works for antique aircraft that are certified as well. Occasionally you see one with a number starting NC12345, on them it just gives a sort of old timey look. I thought the diagonal was incorrect and when I see him again will show him the regs.
 
Mel said:
The "X" when used within the "N" number is NOT within the registration! It is NOT used in communication or anywhere else. The "X" simply replaced the "EXPERIMENTAL" placard on experimental aircraft more than 30 years old or an experimental replica of an aircraft more than 30 years old.

And BTW, the "X" comes after the "N", not before (NX286HS). And the same FAR allows for a minimum size of 2" on these aircraft. ref: Part 45.22(b)
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Mel, do you know if there are any gotchas with the interpretation of 45.22's clause: "and which has the same external configuration as an aircraft built at least 30 years ago"? I'm building an RV-8 and assume that 30 years starts from when the first RV-8 prototype was built. But I'm sure the feds could have some different ideas about what "same external configuration" means if they wanted to (e.g., antenna placement, cowling type, canopy type, prop type).
 
bmellis11 said:
Mel, do you know if there are any gotchas with the interpretation of 45.22's clause: "and which has the same external configuration as an aircraft built at least 30 years ago"? I'm building an RV-8 and assume that 30 years starts from when the first RV-8 prototype was built. But I'm sure the feds could have some different ideas about what "same external configuration" means if they wanted to (e.g., antenna placement, cowling type, canopy type, prop type).
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FWIW, the RV-8 first flew in 1995. Note that the RV-8 flew before both the RV-9 (1997) and the RV-7 (2001).


i-hDWWdJW-XL.jpg
 
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YEP!

Pilot135pd said:
This is very timely for me because I just saw a few planes with NX... this weekend at the STOL competitions.
I don't plan to change any decals but just to expand my knowledge, for my 1969 N52VM:
I can legally just replace the registration on my plane (without telling the FAA) with NX52VM & remove the EXPERIMENTAL sticker?
Then when talking with ATC just say N52VM ?
Click to expand...

Your Wilga shows to be licensed in Experimental Exhibition under 21.191(d) so; part 45.22(b) covers part 21.191(d) and 21.191(g), so yes, it looks like it will qualify.

No notification necessary.

Many FAA Guys don't understand "Experimental" rules in their entirety so I always recommend that anyone using this reg to make a copy of 45.22 and keep it in the aircraft to explain if necessary.
 
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Nope!

bmellis11 said:
Mel, do you know if there are any gotchas with the interpretation of 45.22's clause: "and which has the same external configuration as an aircraft built at least 30 years ago"? I'm building an RV-8 and assume that 30 years starts from when the first RV-8 prototype was built. But I'm sure the feds could have some different ideas about what "same external configuration" means if they wanted to (e.g., antenna placement, cowling type, canopy type, prop type).
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The RV-8 won't be 30 until 2025. Currently the only RVs that qualify are the -1, -3, -4, and -6.
 
Mel said:
Your Wilga shows to be licensed in Experimental Exhibition under 21.191(d) so; part 45.22(b) covers part 21.191(d) and 21.191(g), so yes, it looks like it will qualify.

No notification necessary.

Many FAA Guys don't understand "Experimental" rules in their entirety so I always recommend that anyone using this reg to make a copy of 45.22 and keep it in the aircraft to explain if necessary.
Click to expand...

Thank you .
 
Mel said:
Many FAA Guys don't understand "Experimental" rules in their entirety so I always recommend that anyone using this reg to make a copy of 45.22 and keep it in the aircraft to explain if necessary.
Click to expand...

I totally agree with that advice, even then, I know of at least one instance where showing that to the FAA guys calling it into question wasn’t enough to convince them.
 
Check your operating limitations

Pilot135pd said:
I can legally just replace the registration on my plane (without telling the FAA) with NX52VM & remove the EXPERIMENTAL sticker?
Then when talking with ATC just say N52VM ?
Click to expand...

I have NX??? on my plane. My Operating Limotations say that "EXPERIMENTAL" must be displayed. So the " EXPERIMENTAL" stayed when I went to 2" numbers.

ATC gets N???.
 
koupster said:
I have NX??? on my plane. My Operating Limotations say that "EXPERIMENTAL" must be displayed. So the " EXPERIMENTAL" stayed when I went to 2" numbers.

ATC gets N???.
Click to expand...

As I stated, my question was a hypothetical only to expand my knowledge of the mentioned Regulation because some of what was stated does not apply to my registration. for example my Ops Limits don't mandate the word EXPERIMENTAL anywhere on the plane and I also don't need to install an ELT in my plane.
 
JDeanda said:
Point is, while of course markings should be in accordance with rules and regulations, it doesn’t seem to be rigorously enforced.
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The N number regulations are quite often bent if not broken, and as you have observed, there doesn't seem to be a lot of enforcement.

Several years ago, in preparation for a class I was teaching at FAA, I went around the grounds at the EAA convention with the idea of taking photos of any illegal N numbers I came across. Well, before I was halfway through the grounds my SD card in my camera was full! There were dozens, if not hundreds, of N numbers that didn't meet the regulations. Some were subtle, but many were not so subtle. This included several factory-new aircraft from major manufacturers. I still use some of these photos in my webinar presentations to this day. it was crazy how many illegal numbers there were, and I keep seeing them all the time.
 
A lot of the past Airventure award winners (with their typically very custom paint jobs) have registration numbers that don’t meet the requirements.
 
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