Solution
2.3.11 Aerospace Vehicle Designations and Naming
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k k We “decode” a special version of the KC-135, designated as the NKC-135A. The first letter is the
status prefix symbol, designating a non-standard vehicle, that is a test, modification, experimental, or prototype design. The status prefix “N” designates a vehicle that is in a permanent, special test function. The second and third letters are the modified mission symbol and basic mission symbol, respectively. The basic mission symbol identifies the primary function or capability of the aircraft.
The modified mission symbol identifies modifications to the basic mission. For our example, the basic mission symbol “C” identifies the aircraft as a transport, and the symbol “K” shows it has a modified mission as a tanker. The number “135” in our designation is the design number, desig-nating the manufacturer’s 135th airplane design. Finally, the letter after the number is the series, identifying the first production model of a design and then advancing one letter for each later model.
In our case, the “A” indicates the first model of the 135 airplane design.
To summarize for the aircraft designation NKC-135A, we have
N status prefix permanently operating in special test capacity
K modified mission tanker
C basic mission transport
135 design number 135th design
A series 1st version of this design
Table 2.9 provides a complete list of US Military designator symbols and descriptions for air-craft. As shown in this table, some aircraft also have a vehicle type designation, required only for certain vehicles, such as glider, helicopter, vertical takeoff and landing (VTOL) vehicle, missile, or space vehicle. There is a vehicle type symbol “D” which applies to the ground control equipment for unmanned aerial vehicles, rather than an actual vehicle. An example of the use of a vehicle type designation is the Sikorsky VH-3D Sea King helicopter, as “decoded” below.
status prefix (none)
V modified mission staff
basic mission (none)
H vehicle type helicopter
3 design number 3rd design
D series 4th version of this design
The Sea King was designed as an antisubmarine warfare helicopter, with the “VH” model serving in its modified mission role as the US Presidential helicopter.
Two aircraft identifying numbers, which are not included in the MDS designator, are serial numbers and block numbers. Serial numbers uniquely identify a specific vehicle. The numbering system for serial numbers varies with the different military services. Block numbers identify a manufacturer’s production group of aircraft with the same configuration, within a specific design series. Block number assignments are usually in multiples of five: 1, 5, 10, 15, etc., but intermediate numbers are also sometimes used. For example, the US Air Force F-16 Fighting Falcon has been assigned quite a few block numbers in its modification history. The Block 1 F-16 was an early production model with a black nose cone. Changes for Block 5 aircraft included a low-visibility grey nose cone and the addition of fuselage and tail fin rain water drainage holes. Structural material changes from titanium to aluminum and new material bonding techniques were incorporated into F-16 Block 10 aircraft. Block 15 F-16s had 30% larger horizontal stabilizers, improved radar, and other improvements. The F-16 block numbers now reach 60, with its continuing evolution and improvements.
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Table 2.9 US Military designator symbols and descriptions for aircraft (from “Designating and Naming Military Aerospace Vehicles,” AFJI 16-401, NAVAIRINST 8800.3B, AR 70-50, 14 March 2005).
Status prefix Modified mission Basic mission Vehicle type
G – Permanently grounded
A – Attack A – Attack D – UAV control segment
J – Special test (temporary)
C – Transport B – Bomber G – Glider
N – Special test (permanent)
D – Director C – Transport H – Helicopter
X – Experimental Y – Prototype Z – Planning
E – Special electronic installation
E – Special electronic installation
Q – Unmanned aerial vehicle
F – Fighter F – Fighter S – Spaceplane
H – Search and rescue/medevac
L – Laser V – Vertical takeoff and landing (VTOL)/short takeoff and landing (STOL)
K – Tanker O – Observation Z – Lighter-than-air vehicle L – Cold weather P – Patrol
M – Multi-mission R – Reconnaissance O – Observation S – Antisubmarine
P – Patrol T – Trainer
Q – Drone U – Utility
R – Reconnaissance X – Research S – Antisubmarine
T – Trainer U – Utility V – Staff W – Weather
2.3.11.2 Designations for Missiles, Rockets, Space Probes, Boosters, and Satellites
Let us now look at the DoD designation system for aerospace vehicles other than aircraft, that is, for guided missiles, rockets, probes, boosters, and satellites. We “decode” the designation ASB-11A.
The first letter specifies the launch environment, that is, where the vehicle is launched from, where the “A” designation specifies an air launched vehicle. The second letter specifies the basic mission or the primary function or capability of the vehicle. Space support is the basic mission for our example, indicated by the second letter designation “S”. The vehicle type is specified by the third letter, where “B” signifies a booster in our example. Similar to the aircraft designation, the design number and series number are given by the number “11” and the final letter “A”, respectively. To summarize, the ASB-11A “decodes” as follows.
status prefix (none)
A launch environment air launched
S basic mission space support
B vehicle type booster
11 design number 11th design
A series 1st version of this design
k k Table 2.10 US Military designator symbols and descriptions for guided missiles, rockets, probes, boosters,
and satellites (from “Designating and Naming Military Aerospace Vehicles,” AFJI 16-401, NAVAIRINST 8800.3B, AR 70-50, 14 March 2005).
Status prefix Launch environment Basic mission Vehicle type
C – Captive A – Air C – Transport B – Booster
D – Dummy B – Multiple D – Decoy M – Guided Missile
J – Special test (temporary) C – Container E – Electronic/communication N – Probe N – Special test (permanent) F – Individual G – Surface attack R – Rocket X – Experimental G – Surface I – Aerial/space intercept S – Satellite Y – Prototype
Z – Planning
H – Silo stored L – Launch
detection/surveillance L – Silo launched M – Scientific/calibration M – Mobile N – Navigation
P – Soft pad Q – Drone R – Ship S – Space support
S – Space T – Training
U – Underwater U – Underwater attack W – Weather
ASB-11A is the designation of the Orbital Sciences Pegasus air-launched, space support booster, previously described in Section 1.3.5.6 (Figure 1.80).
Table 2.10 provides a complete list of US Military designator symbols and descriptions for guided missiles, rockets, probes, and satellites. Similar to the aircraft designations, there is an optional status prefix first letter. (The ASB-11A Pegasus launch vehicle example does not have a status prefix.).
2.3.11.3 Designations for Non-Military Aircraft
Designation and naming for non-military aircraft, including commercial and general aviation air-craft, is less standardized, at least among all the different US and international aircraft manu-facturers. In the past, there were some regulated two-letter codes that were used by US aircraft manufacturers for non-military aircraft, but this is no longer necessarily in use. Today, each indi-vidual aircraft manufacturer seems to have its own type of designation and numbering system.
For many, if not most, non-military aircraft, the designation is usually a letter followed by a number. The letter often indicates the aircraft manufacturer, such as “A” for Airbus, “B” for Boe-ing, “C” for Cessna, etc., and the number usually indicates a model number. For example, “B747”
signifies a Boeing model 747 aircraft, a wide-body commercial jet airliner and cargo transport.
Some companies use a two-letter code, which may be a vestige of the old, regulated two-letter des-ignation system, an example being the “PA-31” for the Piper model 31, a cabin-class, twin-engine, general aviation aircraft.
The model number is often followed by a dash and a series number for the specified model, for example “B747-400” being the 400 series of the Boeing 747 model. There is sometimes a suffix letter added to the model or series number to signify a different version. For example, the “F”
in the B747-400F designation is the freighter version of the Boeing B747-400 and the “P” in the PA-31P-350 designation is the pressurized verison of the Piper PA-31-350.
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The non-military aircraft designation should not be confused with the international aircraft registration prefix code. These codes are unique letters and numbers that precede the aircraft reg-istration number. All civil aircraft in the world must be registered in accordance with regulations established by the International Civil Aviation Organization (ICAO). The aircraft registration pre-fix code for the US is “N”, so that a US registered civil aircraft might have a registration number N1234. In the US, the aircraft registration number is commonly called an N number, because of the prefix code, or a tail number, because the registration number is often displayed near the tail of the aircraft.