Construction number locations (M)

From Scramble - The Aviation Magazine

Introduction

Construction numbers (c/n), also called Manufacturer Serial Numbers (MSN), are the prime way to identify a specific airframe. In contrast to the registration (or tail number), the c/n does not change, even when owner changes occur.

(note: all 'left' and 'right' indications are as you look from tail to nose).

Construction number locations

Manufacturers A to B

Manufacturers C to D

Manufacturers E to G

Manufacturers H to L

Manufacturers N to R

Manufacturers S

Manufacturers T to Z

National regulations

Contents 1 Introduction 2 McDonnell Douglas 2.1 MD-11 3 Messerschmitt-Bölkow-Blohm 3.1 Bö105 4 Messerschmitt-Bölkow-Blohm/Kawasaki 4.1 BK117 5 Mikoyan Gurevich (MiG) 5.1 MiG-17 5.2 MiG-21 5.3 MiG-23 5.4 MiG-25 5.5 Mikoyan Gurevich MiG-27 5.6 MiG-29 5.7 MiG-31 6 Mil 6.1 Mi-1 6.2 Mi-2 6.3 Mi-4 6.4 Mi-6 6.5 Mi-8 6.6 Mi-24 6.7 Mi-26 6.8 Mi-34 7 Mooney 7.1 Mooney M20R 8 Myasishchev 8.1 M-101T

McDonnell Douglas

MD-11

The Manufacturers Serial Number plate can be found on the top frame of door 11, the door on the left-hand side, just behind the cockpit. So you need to look up when you enter the aircraft.

Messerschmitt-Bölkow-Blohm

Bö105

This helicopter reveals its details on the outside of the airframe, pity that it is seldom checked as it also contains the exact subtype. The plate is on the right-hand side, left of the cabin door.

The plate on the right-hand side of a Spanish Bö105ATH.

Even when the door is opened, the plate can be checked.

Messerschmitt-Bölkow-Blohm/Kawasaki

BK117

For the EC145, see Eurocopter

The construction number plate can be found on the right side of the aircraft, below the rearmost window, just behind the sliding door.

Mikoyan Gurevich (MiG)

MiG-17

One of the locations were a number can be found is the left-hand side main wheel bay.

The c/n plate as worn in the left-hand side main wheel bay on this MiG-17.

MiG-21

Very much depending on the sub-type, the factory where the aircraft was build and other factors, a plethora of locations are known were some sort of identification can be found. And to make things worse, those locations come in even more combinations, so if possible all should be checked.

1. Looking forward inside the nose wheel bay, on the foremost strut on the left hand side a small plate can be found. Usually a four or five digit number.
2. In the main wheel bays, the same plates can be found, but as those are part of the wing sections, which can be changed!, they should not be regarded as correct unless the nose wheel bay is also checked.
3. A four-digit number, again in the nose wheel bay, punched at the top of the cavity where the wheel itself is stored.
4. Again the nose wheel bay, but this time on the forward bulkhead, a small plate with a four digit number can be found.
5. A longer number, painted on both side panels in the nose wheel bay.

When you are able to check any of these locations, please also note the exact location where you found it, when you send your log to your favourite magazine, which would very much appreciated because a lot is still unknown.

1) The c/n plate on the strut in the nose wheel bay of a MiG-21PFM.

3) The punched in 4-digit number high in the nosewheel bay of a MiG-21SMT.

4) The forward bulkhead in the nose wheel bay of a MiG-21SPS.

MiG-23

As with the MiG-21, several positions are known where construction numbers, line numbers, customer numbers etc can be found. When given the opportunity, as many locations should be checked as possible, where besides the the number itself also the location should be written down. Taking images is even better!

• Usually a five digit number is painted inside the left main wheel bay with single seat variants, which can be easily read of when the covers are open. These are the last five of a longer serial (mostly 10 digits) which also indicates the exact sub type.
• Often a plate can be found in the nose wheel bay, looking backwards, on the aft bulkhead, which shows a four or five digit number.
• Sometimes one or two plates can also be found punched on the forward bulkhead in the left main wheel bay. But those are notoriously known for showing the wrong ID; during the final assembly the wrong set of wings was simply attached to the fuselage in those cases. This is shown by one of the images below.
• Dual seats have a seven digit number painted on the front bulkhead inside the main wheel bay. Officially this number is preceded by the letter A.
• Sometimes dual seats also have a plate in the main landing-wheel bay on the left side.

The usual place for the "famous last five" in the main wheel bay, in this case a MiG-23BN with Luftwaffe serial 20+51.	The same 20+51 also has this small plate in the nose wheel bay.	The c/n plate inside the nose wheel bay of a MiG-23ML.	C/n A1037902 is a former East German MiG-23UB.
Plate inside the left main wheel bay of a MiG-23UB	An example of 'how to send an aviation enthusiast on a wild goose chase' when trying to identify a MiG-23.

MiG-25

Probably depending on the factory, the c/n is either painted in the nose-wheel bay or with an actual plate on the forward bulkhead in the same nose-wheel bay. Sometimes it is also painted in the main wheel bays.

A shot of the long c/n painted in the nosewheel bay of a MiG-25PD. The last digit is missing!

A plate in the nosewheel bay of an MiG-25RB.

Mikoyan Gurevich MiG-27

As with its sister, the MiG-23, MSN plates can be found several locations.

Left hand main landing-gear bay.

MiG-29

When looking forward/up/to your right inside the nose wheel well, you will find the metal plate which contains a four digit number. Both main wheel wells also have a plate, but in order to be sure the plate inside the nose wheel well needs to be checked.

On the bulkhead behind the ejection seat another (five-digit) number is often painted, which are the last five of the Russian serial.

MiG-31

The full c/n is painted in the nose wheel bay and main wheel bay on most occasions.

the full c/n is painted in the main wheel bay on this MiG-31B.

Also on the MiG-31E the full c/n is painted in the main wheel bay.

Mil

Mi-1

At least the later models (including Polish built SM-1s) have the plate on the back of the bulkhead separating the engine room and a luggage compartment at the rear of the fuselage. This compartment can be accessed through a hatch on the left side of the fuselage.

The hatch of a SM-1W, a Polish built Mi-1.

Mi-2

The construction number plate is in the cockpit on the right hand side control panel. It is visible through the lower glass surface of the cockpit. It also painted on both sides of the tail in most cases, but mispaints are known.

Mi-2 plate with PZL plate beneath.

A neat c/n paint job on this Mi-2-tail.

Mi-4

The construction number to be found on the rear side of cockpit bulkhead ??

Mi-6

The construction number is usually painted on the left side of the tail boom.

Mi-8

As with a lot of Soviet & Russian built aircraft, the manufacturer serial number can be found on several places, (partly) depending on the exact type and the factory it was built.

• Military Mi-8s of the first generation often have the c/n painted on both sides of the tailboom or on the fin.
• The second generation Mi-8s (Mi-8M/Mi-17) usually have the c/n painted on the inside of the lid covering the pneumatic system access at the left side of the fuselage, just behind the last window.
• The c/n can often be found inside the cargo bay, e.g. on a cover close to the last window.
• Present probably on all Mi-8s but not normally accessible are the c/n plates in the radio compartment at the rear end of the cargo bay. You have to stand close to the clam-shell doors and look up. There is a ‘hatch’ made of cloth on the ceiling. You need to open it (it is fastened with push buttons) and look into the well which opens up. Looking forward (in the direction of flight) you will see a frame consisting of a left and a right part. Both parts carry a c/n plate (one plate carries just the c/n and the other one the c/n and possibly a date).
• Some (Kazan built) Mi-8MTV-1's are known to have an additional plate on the right side of the fuselage, near the tail boom, which also includes the full type. Those include civil registered Mi-8MTV-1's used by the USAF's 6th SOS (for Special Operations Command) - but this may be due to FAR45 regulations, and not the default.

The lid for the pneumatic system on a Mi-8MTV-1.

Another sample of the lid, c/n 96643.

The plate on the right side for the same c/n 96643.

Mi-24

The construction number plate can be found when you open the radiohatch at the rear of the fuselage. The actual plate than can be found at the side which is closest to the cockpit.
On Russian Mi-24's the c/n is usually also stencilled on the sides of the wingstubs and on the fuselage below those stubs.
On export versions (as far as known) the construction number plate can also be found in the front canopy. On an Hungarian Mi-24P the construction number was also stencilled on the launching rail which is located at the end of the wingstubs. Sometimes plates al also attached to the main doors opening upwards, on both sides of the helicopter. But as those doors are removable any plates found here should be treated with some caution.

Opening the hatch below the tail, which gives access to the radio compartment, also reveals the c/n plate.

The right hand door, looking upwards, of Mi-35 c/n 280854.

Mi-26

The construction number can be found painted on the left hand cockpit wall and can be read off from outside if the right hand cockpit windows are open.
Other places are the cabin doors (two to port and one to starboard) the plate is always found on the left-hand side (in other words, on the leading edge of the port doors and on the trailing edge of the starboard door). Apart from these doors, similar metal plates with the construction number can be found on the forward bulkhead of the freight hold (near the maintenance hatch in the roof on the port side), plus the rear end of the cargo ramp and the two vehicle loading ramps hinged to the latter as well as on some equipment items on the walls of the cargo hold. Finally the construction number can also be found stencilled on the right-hand side of the vertical tunnel in the middle of the freight hold floor where the external sling lock is located. This, however, is usually closed by a hinged door. It is worth checking the construction number in many places as there have indeed been cases where Mi-26s have doors and other items 'borrowed' from other machines.

Mi-34

The c/n plate is located on the right hand side of the central console in the cockpit, and can be easily checked through the lower glass.

Mooney

Mooney M20R

The plate is situated on the fuselage below the lefthandside stabilizer.

Myasishchev

M-101T

The construction number is stencilled on the left side of the fin and the upper surface of the port wing. It is also embossed on a small metal plate found on the tip of the port stabilizer (beneath the elevator horn balance).