iahcsr wrote:FlightLevel360 wrote:iahcsr wrote:39M
N37508 all bright and shiny in new paint VCVBFI 1Nov. Wouldn’t be surprised if UA has the keys and driving it off the lot by the 5th.

According to UA staff it will be delivered some time within the next two weeks.
Also, I noticed that a lot of the B39Ms have registrations beginning with "37." Is that a nod to the 737?
They’re going to wait two weeks? Probably because of the 78J delivery to pay for first.
Nx75yy is the overall pattern, ‘x’ being essentially random and ‘yy’ In numerical sequence. However ‘N37’ does appear six times in the first 11 registrations so there could very well be something to nodding.
You are onto something. We know the last 3 numbers in the sCO scheme mean the equipment number, but the first two are variable. This probably is because the letter "O" can't be used so "CO" couldn't use their code anywhere in their scheme. The 39M is the first aircraft where the second digit means something.
Here's probably more than anyone cares to know about sCO N numbers. There is a pattern to the numbers, understanding some numbers are not available. There are definitely favorite numbers to start with and if not available, they move on to other starting pairs of numbers.
sCO units first and second numbers of each N number:
73G: (700) All except 4 units start with a 1 or 2
738: (201-250), Most start with 1,2,or 3 (favorite starting numbers 13/14/24/26/27/33/34)
738: (251-299), All start with 3 or 7 (favorite starting numbers 73/37/33)
738: (501-542), All but 1 start with 7 or 8 (favorite starting numbers 76/77/78/87) - this scheme does interfere with 39M scheme listed below. Of course, they can't be a dupe, but you do have numbers like N87507 and N37507 with different types. 738's start with a 7 or 8 and 39Ms start with 6 or under
739 (400 range): Vast majority start with 3 or 7, (favorite starting numbers 37/38/39/75/77)
739 (800 range): all start with 6, (favorite numbers 68/63/69)
39M: (7500 range) Different scheme, second number starts with 7, (Note that 16 738 units have a second number starting with 7 and also in 500 range)
752: (100) Most start with a 1, (favorite starting number is 14 and 17)
753: (800) 10 start with 5, 11 start with 7, (favorite starting numbers 75 and 57)
764: (060/070) 15 of 16 start with 6 or 7 (favorite starting numbers 66/67/69/76/77)
772 (001-022) 18 of 22 start with a 7, (favorite starting numbers are 78/77), (those that don't start with 7 - 3 of 4 have 7 as second digit)
77W: (different scheme, but all start with 2, (favorite starting numbers 23/21/26)
788: (901-913) 10 of 12 start with 2, (favorite starting numbers are 27 & 26)
789: (950-999) 16 start with a 2, others with 1,3 or 4, (favorite starting numbers 24/27/26)
7810: (001-099) All start with a 1, (favorite starting numbers 12/13/16)