History of the Delta Launch Vehicle
Frequently Asked Questions
Programs and Links
To Reach the High Frontier: A History of U.S. Launch Vehicles
Many other excellent books about spaceflight are recommended here.
Vehicle DescriptionLetter Designations....Number Designations....Delta Evolution....Current Family....Payload Fairings
Vehicle Intro Stage Modification Delta 1960 1 Modified Thor, MB-3 Blk I engine 2 AJ10-118 (Vanguard-derived propulsion system) 3 Vanguard X-248 motor (Altair) Delta A 1962 1 MB-3 Blk II engine Delta B 1962 2 AJ10-118D - tanks lengthened, higher energy oxidizer used Delta C 1964 3 Scout X-258 motor (Altair 2) or FW-4D [Delta C1] Delta D 1964 0 3 Thor-developed Castor I motors Delta E 1965 0 Castor II motors 1 MB-3 Blk III engine 2 DSV-3E-3 (AJ10-118E) - propellant tanks widened 3 Scout X-258 motor (Altair 2) or FW-4D [Delta E1] (Delta F) Delta E1 without augmentation motors - never flown Delta G 1966 3 none - used a special reentry vehicle for biological recovery (flights 43 & 51 only) (Delta H) Delta G without augmentation motors - never flown Delta J 1968 3 TE-364-3 (Star 37D) (Delta K) Cryogenic upper stage design study - never flown Delta L,M,N 1968 1 Long Tank Thor - tanks lengthened, cylindrical RP-1 tank 3 L: FW-4 M: TE-364-3 N: none M-6,N-6 1970 0 6 Castor II Four Digit Designator (introduced 1972) First digit - Type of First Stage & Augmentation 0 - Long Tank, MB-3 engine, Castor II motors [1968 baseline] 1 - Extended Long Tank, MB-3 engine, Castor II motors  2 - Extended Long Tank, RS-27 engine, Castor II motors  3 - Extended Long Tank, RS-27 engine, Castor IV motors  4 - Extended Long Tank, MB-3 engine, Castor IVA motors [1989-90] (2 missions) 5 - Extended Long Tank, RS-27 engine, Castor IVA motors  (1 mission) 6 - Extra Extended Long Tank, RS-27 engine, Castor IVA motors  7 - Extra Extended Long Tank, RS-27A engine, GEM 40 motors  8 - Delta III Tank, RS-27A engine, GEM 46 motors, 4-meter fairing  Second digit - Number of Augmentation Motors 3, 4, 6, or 9 solid rocket motors Third digit - Type of Second Stage 0 - AJ10-118F (Aerojet) (DSV-3N-4) (Titan 3C Transtage derivative)  1 - TR-201 (TRW) *  2 - AJ10-118K (Aerojet)  3 - RL10B-2 (Pratt & Whitney)  Fourth digit - Type of Third Stage 0 - No Third Stage 2 - FW-4  (digit never used) 3 - Star 37D (TE-364-3)  4 - Star 37E (TE-364-4)  5 - Star 48B (TE-M-799) (PAM-D Derivative)  6 - Star 37FM (TE-M-783)  Dash numbers - Fairing Size -8 - 8-foot cylindrical (standard on 2000- and 3000-series)  -9.5 - 9.5-foot (standard on Delta II, thus omitted from the Flight Log)  -10 - 10-foot metal skin-and-stringer  -10C - 10-foot composite  -10L - lengthened 10-foot composite  Example: Delta 7925-10 Extra Extended Long Tank, RS-27A engine, nine GEM 40 motors, AJ10-118K second stage, Star 48B third stage, 10-foot diameter fairing. Four Digit Designator (unused revision) A new Four Digit Designator system was proposed in 2002, revised to handle the current variety of configurations while also allowing the first digit to match the overall vehicle type. It was expected to begin use around 2008. However with the cancellation of Delta III and a different descriptor system for Delta IV, this revision does not appear to have ever been put into use. First digit - Type of First Stage 2 - Delta II booster 3 - Delta III booster 4 - Delta IV booster Second digit - Number of Augmentation Motors 0, 2, 3, 4, or 9 solid rocket motors Third digit - Type of Second Stage 2 - AJ10-118K (Aerojet) 4 - RL10B-2 (Pratt & Whitney) with 4-meter tankage 5 - RL10B-2 (Pratt & Whitney) with 5-meter tankage Fourth digit - Type of Third Stage 0 - No Third Stage 5 - Star 48B (TE-M-799) (PAM-D Derivative) 6 - Star 37FM (TE-M-783) Auxiliary letter - Alternate Configurations blank - Standard H - Heavy Configuration Delta II - GEM 46 booster motors Delta IV - 2 CBC [Common Booster Core] strap-ons Dash numbers - Fairing Size Delta II - diameter in feet 9.5 standard, metal skin-and-stringer 10C composite 10L lengthened composite Delta III, IV - length in meters
The Delta Family of Launch Vehicles
The Delta Family of Launch Vehicles
Delta Payload Fairings
Compiled by Kevin S. Forsyth. Last update 27 November 2017.
Visits since 04-Dec-97