N number size requirements

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KG
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N number size requirements

Post by KG »

I split this off from the other thread so as to avoid hijacking.... hope this helps someone.


I did a lot of research on the N number size requirements a couple of years ago. It is confusing. What I found was that 2 inch numbers are ok for airplanes 30 years and older.

The pertinent paragraph is:
14 CFR Part 45
Identification and Registration Markings
Subpart C--Nationality and Registration Marks
Sec. 45.22 Exhibition, antique, and other aircraft: Special rules.

(b) A small U.S.-registered aircraft built at least 30 years ago or a
U.S.- registered aircraft for which an experimental certificate has been
issued under Sec. 21.191(d) or 21.191(g) for operation as an exhibition
aircraft or as an amateur-built aircraft and which has the same external
configuration as an aircraft built at least 30 years ago may be operated without displaying
marks in accordance with Secs. 45.21 and 45.23 through 45.33 if:
(1) It displays in accordance with Sec. 45.21(c) marks at least 2 inches
high on each side of the fuselage or vertical tail surface consisting of
the Roman capital letter "N" followed by:
(i) The U.S. registration number of the aircraft;
..... (note: 45.21(c) refers to contrast, legibility, etc.)

Then there is the question of repainting... Section 45.29 appears to say that if you repaint your numbers they have to be big... but ... it refers "antique" airplanes back to 45.22, which describes antique airplanes as being built at least 30 years ago.

Sec. 45.29 Size of marks.
(a) Except as provided in paragraph (f) of this section, each operator
of an aircraft shall display marks on the aircraft meeting the size
requirements of this section.
(b) Height. Except as provided in paragraph (h) of this part, the
nationality and registration marks must be of equal height and on--
(1) Fixed-wing aircraft, must be at least 12 inches high, except that:
(i) An aircraft displaying marks at least 2 inches high before November
1, 1981 and an aircraft manufactured after November 2, 1981, but before
January 1, 1983, may display those marks until the aircraft is repainted or the marks are repainted, restored, or changed;
(ii) Marks at least 3 inches high may be displayed on a glider;
(iii) Marks at least 3 inches high may be displayed on an aircraft for
which an experimental certificate has been issued under Sec. 21.191(d)
or 21.191(g) for operating as an exhibition aircraft or as an amateur-built
aircraft when the maximum cruising speed of the aircraft does not exceed
180 knots CAS; and
(iv) Marks may be displayed on an exhibition, antique, or other aircraft
in accordance with Sec. 45.22.



12 inch numbers are required to cross an ADIZ and there is no ADIZ on our border with Canada. There is also no ADIZ between most of mainland Alaska and Canada so if you fly up the highway to Alaska, you are ok with 2 inch numbers. There is an ADIZ in Southeast Alaska, so if you go up the coast to Alaska you might cross an ADIZ, depending on your route.

Sec. 45.29 Size of marks.
(h) After March 7, 1988, each operator of an aircraft penetrating an
ADIZ
or DEWIZ shall display on that aircraft temporary or permanent
nationality and registration marks at least 12 inches high.
us-adiz.jpg
photo (1).PNG
If you do cross an ADIZ, temporary 12 inch numbers are ok (so you can use tape)
14 CFR Part 45
Identification and Registration Markings
Subpart C--Nationality and Registration Marks
Sec. 45.21 General.
(c) Aircraft nationality and registration marks must--
((3) It is marked temporarily to meet the requirements of Sec.
45.22(c)(1)

Sec.45.22
(c) No person may operate an aircraft under paragraph (a) or (b) of this
section--
(1) In an ADIZ or DEWIZ described in Part 99 of this chapter unless it
temporarily bears marks in accordance with Secs. 45.21 and 45.23 through
45.33;


And you can pass through Canada in a US registered airplane with 2 inch numbers. Their regs say that if it is a foreign registered aircraft it has to meet the rules of the foreign state.

Here is their rule:
Canadian Aviation Regulations (CARs) 2011-2
Subpart 2 - Aircraft Marking and Registration
Content last revised: 2003/12/01
DIVISION I - AIRCRAFT MARKS
Requirements for Marks on Aircraft
202.01 (1) Subject to subsection (2), no person shall operate an aircraft in Canada unless its marks are visible and are displayed
(a) in the case of a Canadian aircraft, in accordance with the requirements of the Aircraft Marking and Registration Standards; and
(b)in the case of an aircraft registered in a foreign state, in accordance with the laws of that foreign state.
Last edited by KG on Wed Apr 24, 2013 11:26 am, edited 7 times in total.
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bigrenna
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delete

Post by bigrenna »

delete
Last edited by bigrenna on Mon Jun 29, 2015 1:41 pm, edited 1 time in total.
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canav8
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Re: N number size requirements

Post by canav8 »

bigrenna wrote:Yes, but I thought if you repainted, than you were required to go to standard size.
Thats what I thought. If you just touched up the paint then you could get away with it.Like Keith said, it is confusing!
52' C-170B N2713D Ser #25255
Doug
bagarre
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Re: N number size requirements

Post by bagarre »

14 CFR 45.29(b)(i) wrote:(An aircraft displaying marks at least 2 inches high before November 1, 1981 and an aircraft manufactured after November 2, 1981, but before January 1, 1983, may display those marks until the aircraft is repainted or the marks are repainted, restored, or changed;
Nope.

But we fall under 14 CFR 45.22(b) anyway.

Also, the Washington DC SFRA does not require 12" numbers as it is not an ADIZ or DEWIZ described in Part 99.
It is a Special Flight Rules Area described under 14 CFR 93.339 that everyone thinks of as an ADIZ.

I went thru this exercise last year and almost had to write out CFR 14 in disjunctive normal form to be sure.
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KG
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Re: N number size requirements

Post by KG »

Yes, you need a lot of patience to sort through all this. I've highlighted the important paragraph from 45.29 below. I'll go back and edit my original post so this is all in one place. 45.29 para. (b)1(iv) refers us back to 45.22, which in turn describes antique aircraft as being at least 30 years old.

Sec. 45.29 Size of marks.

(a) Except as provided in paragraph (f) of this section, each operator
of an aircraft shall display marks on the aircraft meeting the size
requirements of this section.
(b) Height. Except as provided in paragraph (h) of this part, the
nationality and registration marks must be of equal height and on--
(1) Fixed-wing aircraft, must be at least 12 inches high, except that:
(i) An aircraft displaying marks at least 2 inches high before November
1, 1981 and an aircraft manufactured after November 2, 1981, but before
January 1, 1983, may display those marks until the aircraft is repainted or the marks are repainted, restored, or changed;
(ii) Marks at least 3 inches high may be displayed on a glider;
(iii) Marks at least 3 inches high may be displayed on an aircraft for
which an experimental certificate has been issued under Sec. 21.191(d)
or
21.191(g) for operating as an exhibition aircraft or as an amateur-built
aircraft when the maximum cruising speed of the aircraft does not exceed
180 knots CAS; and
(iv) Marks may be displayed on an exhibition, antique, or other aircraft
in accordance with Sec. 45.22.

(2) Airships, spherical balloons, and nonspherical balloons, must be at
least 3 inches high; and
(3) Rotorcraft, must be at least 12 inches high, except that rotorcraft
displaying before April 18, 1983, marks required by Sec. 45.29(b)(3) in
effect on April 17, 1983, and rotorcraft manufactured on or after April
18,
1983, but before December 31, 1983, may display those marks until the
aircraft is repainted or the marks are repainted, restored, or changed.
(c) Width. Characters must be two-thirds as wide as they are high,
except
the number "1", which must be one-sixth as wide as it is high, and the
letters "M" and "W" which may be as wide as they are high.
(d) Thickness. Characters must be formed by solid lines one-sixth as
thick as the character is high.
(e) Spacing. The space between each character may not be less than one-
fourth of the character width.
(f) If either one of the surfaces authorized for displaying required
marks under Sec. 45.25 is large enough for display of marks meeting the size
requirements of this section and the other is not, full-size marks shall
be placed on the larger surface. If neither surface is large enough for
full-size marks, marks as large as practicable shall be displayed on the
larger of the two surfaces. If any surface authorized to be marked by Sec. 45.27 is not large enough for full-size marks, marks as large as practicable shall be placed on the largest of the authorized surfaces.
(g) Uniformity. The marks required by this part for fixed-wing aircraft
must have the same height, width, thickness, and spacing on both sides
of the aircraft.
(h) After March 7, 1988, each operator of an aircraft penetrating an
ADIZ or DEWIZ shall display on that aircraft temporary or permanent
nationality and registration marks at least 12 inches high.
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Bruce Fenstermacher
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Re: N number size requirements

Post by Bruce Fenstermacher »

bigrenna wrote:Yes, but I thought if you repainted, than you were required to go to standard size.
There was a time when this was the case as the regulation evolved. But it is no longer the case.
CAUTION - My forum posts may be worth what you paid for them!

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Email: brucefenster at gmail.com
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KG
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Re: N number size requirements

Post by KG »

Bruce Fenstermacher wrote:
bigrenna wrote:Yes, but I thought if you repainted, than you were required to go to standard size.
There was a time when this was the case as the regulation evolved. But it is no longer the case.
That's the way I interpret it..... if you painted a 1956 Cessna 170 in 1985 you would have had to use 12 inch numbers... but if you repainted that same airplane again today you could 2 inch numbers. I think.

I'm sure someone would interpret it differently.... heck, I think it's ok to fly around without a back seat.. so take my opinion and apply your own logic.

Here is the link if you want to pick through it yourself. To tell the truth, the hardest part was finding a map (or is that a chart?) of the ADIZ.

http://www.ecfr.gov/cgi-bin/text-idx?c= ... 22&idno=14

Happy Flying,
Keith
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hilltop170
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Re: N number size requirements

Post by hilltop170 »

It plainly says if the airplane displayed 2" numbers before 1981 it is exempt. All 170s displayed 2" numbers before 1981.
Richard Pulley
2014-2016 TIC170A Past President
1951 170A, N1715D, s/n 20158, O-300D
2023 Best Original 170A at Sault Ste. Marie
Owned from 1973 to 1984.
Bought again in 2006 after 22 years.
It's not for sale!
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blueldr
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Re: N number size requirements

Post by blueldr »

Richard,
For crisake, stop simplifying it for these guys! Can't you understand that they have a good thing going now and don't want to spoil it.
BL
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falco
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Re: N number size requirements

Post by falco »

dang. this is sillier than the backseat discussion. the rules are abundantly clear on this one.
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KG
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Re: N number size requirements

Post by KG »

Yep, abundantly clear, until it's repainted. Then it gets muddy.

I nominate Richard for FAA Administrator. bluelder can be his deputy. Let's put some common sense up there...... :D
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falco
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Re: N number size requirements

Post by falco »

Sec 45.22(b) as quoted above negates the need to comply with 45.21, 45.23 thru 45.53 for small US registered AC built at least 30 years ago if you have the 2 inch numbers properly displayed. The stuff about repainting is thus irrelevant to AC that comply with 45.22(b), because it is contained in one of the sections with which you need not comply.

Sec 45.29 (b) (iv) even refers you back to sec 45.22(b)


I find this quite clear, thanks.
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KG
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Re: N number size requirements

Post by KG »

Sorry if I bored you falco. Several participants of this forum had expressed some confusion over the regs. I was confused about the details a couple of years ago until I did some research. When I was trying to figure out the rules, I got some bad information from otherwise reputable sources so I thought I might save someone else some trouble.

More than a few people have read:

(i) An aircraft displaying marks at least 2 inches high before November
1, 1981 and an aircraft manufactured after November 2, 1981, but before
January 1, 1983, may display those marks until the aircraft is repainted or the marks are repainted, restored, or changed;

and thought that meant that they had to change to 12 inch numbers when the plane was repainted.

Obviously, you already knew the correct answer. I simply tried to clarify it with references so the next time somebody asks..."do I need 12 inch numbers?" or "is it ok to fly into Canada with 2 inch numbers?".... .maybe they could find the answers all in one place. I thought somebody might find the information helpful.

Besides, I had been drinking a lot of coffee and didn't have much else to do today. :D

I'll be more careful with my posting in the future. Happy Flying
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falco
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Re: N number size requirements

Post by falco »

No Ken, no need for you to apologize. I appreciate your posting the regs and adding to your original post, you have made this clearer for all.

It seems, however, that there are a number of things posted of late that are either debates about someones extremely rigid or incorrect interpretations of the regs. ( the idea that letter on 8.50 tires requires goodyear wheels , major alterations and 337s required to remove nonessential equipment like a rear seat, size of numbers on old airplanes, etc.) I think the discussions on this forum usually come to the right conclusion, but sometimes the process is difficult to read.

If my posts today sounded annoyed, I apologize.
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Re: N number size requirements

Post by bagarre »

Part 45.421(c)(1) wrote:Except as provided in paragraph (d) of this section, be painted on the aircraft or affixed by any other means insuring a similar degree of permanence;
Part 54.21(d) wrote: The aircraft nationality and registration marks may be affixed to an aircraft with readily removable material if—

(1) It is intended for immediate delivery to a foreign purchaser;
(2) It is bearing a temporary registration number; or
(3) It is marked temporarily to meet the requirements of § 45.22(c)(1) or § 45.29(h) of this part, or both.
Part 54.22(c)(1) wrote: In an ADIZ or DEWIZ described in Part 99 of this chapter unless it temporarily bears marks in accordance with §§ 45.21 and 45.23 through 45.33;
Part 45.29(h) wrote:After March 7, 1988, each operator of an aircraft penetrating an ADIZ or DEWIZ must display on that aircraft temporary or permanent nationality and registration marks at least 12 inches high.
So yes, your registration numbers need to be painted.

In the other thread, I was referring to ornamental stripes and not registration numbers.
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