Delta

Delta LV Family
From left: Thor-Delta, Delta A, Delta B, Delta E, Delta M, Delta 2000, Delta 6000, Delta 7000 Heavy, Delta 3, Delta IV, Delta Heavy.
Credit - © Mark Wade

The Delta space launch family had its roots in the Thor IRBM. Thor was a 2400 km range missile with essentially the same characteristics as the Army's Jupiter. It was developed by Douglas Aircraft in one of the most accelerated crash programs in history. 'Chief Designer' of the Thor was Jack Bromberg. He was not educated formally as an engineer, but was smart and dynamic. Company owner Donald Douglas had hired him back in the 1930's. He was a major influence in Douglas' winning response to the USAF request for proposal, which emanated from USAF Missile Czar General Bernard Schriever.

The Air Force requirement was to build an IRBM around a discarded rocket motor design. The engine had been developed as the sustainer engine for the Atlas missile when the requirement was to launch a 2700 kg thermonuclear warhead over an intercontinental range. When it became apparent that the warhead could be reduced to less than half that weight, the Atlas was downsized, and the 68 tonne thrust sustainer motor was no longer required.

Douglas flew a first prototype only thirteen months after go-ahead. Sixty Thors were deployed to missile sites in Great Britain under Project Emily. After a few years the Thors were withdrawn from Britain (and the Jupiters from Turkey) as part of the secret codicil of Kennedy's deal to end the Cuban Missile Crisis. A few continued in an offensive military role as a nuclear-tipped anti-satellite system, based on Johnson Atoll in the Pacific, until the end of the early 1970's. Surplus Thors were used for a variety of suborbital re-entry vehicle tests.

After the Sputnik shock, all available assets were pressed into service. Thor was developed into a workhorse for the space programme. A fundamental problem was that the thrust to weight ratio of the basic vehicle left little margin for growth or larger upper stages. This was solved by using Castor solid rockets strapped to the base of the vehicle to increase the lift-off thrust. Thor developed into the standard American medium-lift launcher, continually evolving through the use of more and larger strap-on boosters, a cylindrical and stretched core, and enlarged upper stages. After going through a bewildering myriad of military versions it emerged as the standardised, reliable and economical Delta commercial satellite launch vehicle by the mid-1960's. Improved Delta versions continued in production into the next millennium, with over 700 airframes completed, and no end of production in sight.

This incredible evolution resulted in the payload into a geosynchronous transfer orbit increasing from 68 kg in 1962 to 3810 kg by 2002. The Delta 3 introduced a new cryogenic upper stage in 1998. However the vehicle began tests just as the satellite market collapsed. It was flown only three times, two of the launches being failures. Meanwhile the most numerous and successful version, the Delta 7000 series, continued in service. The Delta-4, the winner of the bulk of the orders for the USAF EELV requirement, introduced a new Lox/LH2 cryogenic core vehicle. This could be used with existing Delta upper stages. It could be flown without augmentation, or use 2-4 large GEM-60 solid rocket boosters. The heavy lift version uses two core vehicles as a first stage, flanking the single core vehicle second stage.

The configuration of Delta vehicles has been encoded for thirty years as follows:

  • First digit: basic vehicle configuration:

    This was defined up to 2004 as follows:

    • 0 = Castor 2 solid propellant strap-ons, Long Tank Thor core with MB-3 engine
    • 1 = Castor 2 strap-ons, Extended Long Tank core with MB-3 engine
    • 2 = Castor 2 strap-ons, Extended Long Tank core with RS-27 engine (derived from surplus H-1 engines of the Saturn IB).
    • 3 = Castor 4 solid propellant strap-ons, Extended Long Tank core with RS-27 engine
    • 4 = Castor 4A strap-ons, Extended Long Tank core with MB-3 engine
    • 5 = Castor 4A strap-ons, Extended Long Tank core with RS-27 engine
    • 6 = Castor 4A strap-ons, Extra Extended Long Tank core with RS-27 engine
    • 7 = GEM-40 solid propellant strap-ons, Extra Extended Long Tank core with RS-27A engine
    • 8 = GEM-46 solid propellant strap-ons, Delta-3 strengthened Extra Extended Long Tank core with RS-27A engine
    • 9 = GEM-60 solid propellant strap-ons, Delta-4 Lox/LH2 cryogenic core with RS-68 engine.

    After 2004 this was revised to:

    • 2 = Delta II first stage (previously Delta 7000 series)
    • 3 = Delta III first stage (previously Delta 8000 series)
    • 4 = Delta IV first stage (previously Delta 9000 series)

  • Second digit: Number of solid propellant strap-ons (0, 3, or 9 prior to Delta IV. 0, 2, or 4 for Delta-4).

  • Third digit: Second stage

    • 0 = Delta storable propellant stage with AJ10-118 series engines
    • 1 = Delta storable propellant stage with TR-201 engines (surplus TRW Apollo Lunar Module upper stage engines)
    • 2 = Delta K storable propellant stage with AJ10-118K engine
    • 3 = Delta-3 Lox/LH2 cryogenic upper stage with RL10B-2 engine
    • 4 = Delta-4 Lox/LH2 cryogenic upper stage with 4 m diameter
    • 5 = Delta-4 Lox/LH2 cryogenic upper stage with 5 m diameter

  • Fourth digit: Third stage

    • 0 = No third stage
    • 1 = Not used
    • 2 = Not used
    • 3 = Star 37D / TE-364-3 solid propellant kick stage
    • 4 = Star 37E / TE-364-4 solid propellant kick stage
    • 5 = Star-48B / PAM-D solid propellant kick stage (often listed as '0' upper stage with a PAM-D due to the modular nature of the PAM configuration).
    • 6 = Star 37FM solid propellant kick stage
  • Optional letter after fourth digit: An 'H' here indicates a 'Heavy' configuration. For Delta II, this is use of 46 inch diameter GEM solid strap-on motors in place of the standard Castor motors. For Delta IV, it indicates use of two strap-on Common Booster Cores (CBC) to supplement the CBC on the core stage.
  • Dash number: Payload fairing. For Delta II, this indicates the diameter of the fairing in feet. For Delta III or Delta IV, it indicates the length of the fairing in metres.

Thor DM-18 Single stage vehicle adapted from Thor IRBM with no upper stage....more.
Thor Also PTM-17A, USM-75...more.
Thor Able Thor with Able stage derived from Vanguard second stage, consisting of 1 x Thor DM-18A + 1 x AJ10-40....more.
Thor Agena A 2 stage vehicle consisting of 1 x Thor DM-18A + 1 x Agena A...more.
Delta Commercial name for the military's Thor-Delta. The name of the Delta second stage eventually was applied to subsequent commercial follow-ons....more.
Thor Able-Star As Thor Able but with enlarged second Ablestar second stage with 2 1/2 x greater burn time....more.
Thor Agena B 2 stage vehicle consisting of 1 x Thor DM-21 + 1 x Agena B...more.
  Thor Hydra Thor with Hydra liquid oxygen/hydrogen pressure-fed upper stage. Never went beyond initial hardware testing. However such a stage would have vastly increased Thor-Ablestar...more.
Delta A 3 stage vehicle consisting of 1 x Thor DM-21 + 1 x AJ10-118 + 1 x Altair...more.
Delta B 3 stage vehicle consisting of 1 x Thor DM-21 + 1 x AJ10-118A + 1 x Altair...more.
Thor Agena D 2 stage vehicle consisting of 1 x Thor DM-21 + 1 x Agena D...more.
  Thor DSV-2D Single stage vehicle consisting of 1 x Thor DM-21...more.
Thor DSV-2E Single stage vehicle consisting of 1 x Thor DM-18A...more.
Delta C Unaugmented Thor with Delta D and solid propellant upper stages....more.
  Thor DSV-2F Single stage vehicle consisting of 1 x Thor DM-18A...more.
Delta D 4 stage vehicle consisting of 3 x Castor + 1 x Thor DSV-2C + 1 x Delta D + 1 x Altair 2...more.
  Thor DSV-2G 2 stage vehicle consisting of 1 x Thor DM-18A + 1 x AJ10-118...more.
Thor DSV-2J Single stage vehicle consisting of 1 x Thor DM-18A...more.
Delta E Thor augmented with 3 x Castor 2 motors with Delta E and FW-4D or other upper stages....more.
Thor Burner Thor DM-18A with 'Burner' upper stage solid rocket packages for launch of classified payloads....more.
Delta G 3 stage vehicle consisting of 3 x Castor + 1 x Thor DSV-2C + 1 x Delta E...more.
Thorad Agena D SLV-2G 3 stage vehicle consisting of 3 x Castor 2 + 1 x LT Thor + 1 x Agena D...more.
  Thorad Agena Thor Agena upgraded with Extended Length Tank Thor stage,...more.
Delta J 4 stage vehicle consisting of 3 x Castor + 1 x Thor DSV-2C + 1 x Delta E + 1 x Star 37D...more.
Delta M Long Tank Thor augmented with 3-6 Castor 2 boosters and Delta E / Burner 2 upper stages....more.
Delta N Long Tank Thor augmented with 3-6 Castor 2 boosters and Delta E upper stage....more.
  Delta L 4 stage vehicle consisting of 3 x Castor 2 + 1 x LT Thor DSV-2L-1B + 1 x Delta E + 1 x FW4D...more.
Thorad Agena D SLV-2H Thor Agena upgraded with Long Tank Thor stage. Variant with straight tank from Delta was Thorad (Long Tank Augmented Thrust Thor Delta)...more.
Delta 0100 The military Thor-Delta vehicles were developed into the first of a series of commercial satellite launch vehicles. The Delta 0100 series featured Castor 2 solid...more.
Delta 1000 The Delta 1000 series used Castor 2 strap-ons and the Extended Long Tank core with MB-3 engine....more.
Delta 2000 The Delta 2000 series used Castor 2 strap-ons together with an Extended Long Tank core equipped with the more powerful RS-27 engine. This engine was derived from...more.
Delta 3000 The Delta 3000 series upgraded the boosters to Castor 4 solid propellant strap-ons, while retaining the Extended Long Tank core with RS-27 engine. The 3910 series...more.
N Licensed version of Delta built in Japan using both US and Japanese components. 4 stage vehicle consisting of 3 x Castor 2 + 1 x LT Thor N + 1 x LE-3 + 1 x Star 37N...more.
  Thor DSV-2U Single stage vehicle consisting of 1 x Thor DM-18A...more.
N-2 Licensed version of Delta built in Japan using both US and Japanese components. 4 stage vehicle consisting of 9 x Castor 2 + 1 x ELT Thor N + 1 x AJ10-118FJ + 1 x Star 37E....more.
H-1 Japanese license-built version of Delta launch vehicle, with Japanese-developed upper stages....more.
  Barbarian MDD Proposed launch vehicle for large SDI 'Star Wars' payloads. Expected to cost $ 400-500 million, the Barbarian could place the Zenith-Star chemical laser into low...more.
Delta 4000 The Delta 4000 series used more powerful Castor 4A strap-ons, but the old Extended Long Tank core with MB-3 engine. Only two of these were launched....more.
Delta 5000 The Delta 5000 series used the more powerful Castor 4A strap-ons but with the Extended Long Tank core with RS-27 engine. Only one was launched....more.
Delta 6000 The Delta 6000 series used the Castor 4A strap-ons with the ultimate Extra Extended Long Tank core with RS-27 engine....more.
Delta 7000 The Delta 7000 series used GEM-40 strap-ons with the Extra Extended Long Tank core, further upgraded with the RS-27A engine....more.
Delta 3 Delta 3 was an attempt by the manufacturer to provide the ultimate development of the original Delta booster. The core vehicle was beefed-up to accomodate much...more.
Delta IV Heavy Heavy lift all-cryogenic launch vehicle using two Delta-4 core vehicles as first stage flanking a single core vehicle as second stage. A heavy upper stage is carried...more.
Delta IV Medium Basic Delta-4 vehicle with no strap-ons, the core vehicle, and RL10B-1 upper stage with a 4 m diameter payload fairing. World's first all-cryogenic launch vehicle....more.
Delta IV Medium+ (5.2) As Delta 4 medium but with 2 x GEM-60 solid rocket boosters and a 5 m diameter payload fairing....more.
  Delta IV Medium+ (5.4) As Delta 4 medium but with 4 x GEM-60 solid rocket boosters and a 5 m diameter payload fairing....more.
  Delta IV Small Light launch vehicle using the Delta-4 core with the traditional Delta K and PAM-D upper stages. 2 m diameter payload fairing....more.
Delta IV Medium+ (4.2) As Delta 4 medium but with 2 x GEM-60 solid rocket boosters and a 4 m diameter payload fairing....more.
Delta 7000H Version of Delta 7000 using much larger GEM 46 solid rocket motors originally developed for the Delta 3....more.
  Delta IV Heavy Upgrade 30 t Upgrade to Delta IV Heavy by adding 4 GEM-60 solid rocket boosters. 6.5 m diameter payload fairing. Introduction would require modifications to existing launch pads....more.
  Delta IV Heavy Upgrade 35 t Upgrade to Delta IV Heavy by adding RS-68B upgraded engines to the core vehicles and an AUS-60 upper stage powered by 2 MB-45 or RL-45 20 tonne thrust Lox/LH2 engines....more.
  Delta IV Heavy Upgrade 40 t Upgrade to Delta IV Heavy by adding 4 GEM-60 solid rocket boosters, RS-68 Regen upgraded engines with regeneratively-cooled nozzles to the core vehicles, and cryogenic...more.
  Delta IV Heavy Upgrade 42 t Upgrade to Delta IV Heavy by adding new RS-800 engines to the core vehicles, an AUS-60 upper stage powered by 2 MB-60 or RL-60 27 tonne thrust Lox/LH2 engines,...more.
  Delta IV Heavy Upgrade 43 t Upgrade to Delta IV Heavy by adding 4 GEM-60 solid rocket boosters, RS-68 Regen upgraded engines with regeneratively-cooled nozzles to the core vehicles, cryogenic...more.
  Delta IV Heavy Upgrade 45 t Upgrade to Delta IV Heavy by adding 6 GEM-60 solid rocket boosters, RS-68B upgraded engines to the core vehicles, and an AUS-60 upper stage powered by 1 MB-60 or...more.
  Delta IV Heavy Upgrade 48 t Upgrade to Delta IV Heavy by adding 4 GEM-60 solid rocket boosters, RS-68 Regen upgraded engines with regeneratively-cooled nozzles to the core vehicles, cryogenic...more.
  Delta IV Heavy Upgrade 53 t Upgrade to Delta IV Heavy by clustering five common booster modules, using an AUS-60 upper stage powered by 2 MB-60 or RL-60 27 tonne thrust Lox/LH2 engines, and...more.
  Delta IV Heavy Upgrade 67 t Upgrade to Delta IV Heavy by clustering seven common booster modules, and using an AUS-60 upper stage powered by 2 MB-60 or RL-60 27 tonne thrust Lox/LH2 engines....more.
  Delta IV Heavy Upgrade 70 t Upgrade to Delta IV Heavy by clustering seven common booster modules, using an AUS-60 upper stage powered by 3 MB-60 or RL-60 27 tonne thrust Lox/LH2 engines. A...more.
  Delta IV Heavy Upgrade 76 t Upgrade to Delta IV Heavy by clustering seven common booster modules, using an AUS-60 upper stage powered by 3 MB-60 or RL-60 27 tonne thrust Lox/LH2 engines, and...more.
  Delta IV Heavy Upgrade 87 t Upgrade to Delta IV Heavy by clustering seven common booster modules, using a new RS-800K engine in the booster stages, and an AUS-60 27 tonne thrust Lox/LH2 upper...more.
  Delta IV Heavy Upgrade 94 t Upgrade to Delta IV Heavy by clustering seven common booster modules, using a new RS-800K engine in the booster stages, an AUS-60 upper stage powered by 4 MB-60...more.
  Next Genertion Delta 100 t Conceptual next generation Delta booster beyond Delta IV Heavy, equalling Saturn V of the 1960's in payload capability. The booster would use two parallel 7-m-diameter...more.
 
 
 
 
 
 
 
 
 

Contact us with any corrections, additions, or comments.
Conditions for use of drawings, pictures, or other materials from this site..
To contact astronauts or cosmonauts.

© Mark Wade, 1997 - 2007 except where otherwise noted.

 
Encyclopedia Astronautica
topic index
0 - A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - Ra - Re - Sa - Sf - Sp - T - U - V - W - X - Y - Z