The Delta A used the MB-3 Block II engine, with of thrust versus for the Block I.[1] [2]
13. 2 October 1962 – Explorer 14 (EPE-B).
14. 27 October 1962 – Explorer 15 (EPE-C).
The Delta B introduced the upgraded AJ10-118D upper stage, a three-foot propellant tank extension, higher-energy oxidizer, and solid-state guidance system. With the Delta B the Delta program went from "interim" to "operational" status. Delta B could launch to GTO.[2]
15. 13 December 1962. Relay 1, second NASA communications satellite, the NASA communications satellite first active one.
16. 13 February 1963. Pad 17B. Syncom 1; Thiokol Corporation Star-13B solid rocket as apogee motor.
20. 26 July 1963. Syncom 2; geosynchronous orbit, but inclined 33.0° due to the limited performance of the Delta rocket.
For Delta C, the third stage Altair was replaced with Altair 2. The Altair 2 had been developed as the ABL X-258 for the Scout vehicle and was longer, 10% heavier, and with 65% more total thrust. OSO 4 is an example of a Delta C launch.
Delta D, also known as Thrust Augmented Delta, was a Delta C with the Thrust Augmented Thor core plus three Castor 1 boosters.
25. 19 August 1964. Syncom 3, the first geostationary communications satellite.
30. 6 April 1965. Intelsat I.
First Delta E: 6 November 1965; launched GEOS 1
This launch vehicle was not built.
The Delta G was a Delta E without the third stage. The two-stage vehicle was used for two launches: Biosatellite 1 on 14 December 1966 and Biosatellite 2 on 7 September 1967.[1]
The Delta J used a larger Thiokol Star 37D motor as the third stage and was launched once on 4 July 1968 with Explorer 38.[1]
This launch vehicle was not built.[3]
The Delta L introduced the Extended Long Tank first stage with a uniform diameter and used the United Technologies FW-4D motor as a third stage.
The Delta M first stage consisted of a Long Tank Thor with MB-3-3 engine augmented with three Castor 2 boosters. The Delta E was the second stage, with a Star 37D (Burner 2) third stage/apogee kick motor. There were 12 successful Delta M launches from 1968 until 1971.[4]
The Delta N combined a Long Tank Thor (MB-3-3 engine) first stage augmented with three Castor 2 boosters and a Delta E second stage. There were six successful Delta N launches from 1968 until 1972.[5]
The "Super Six" was a Delta M or Delta N with three additional Castor 2 boosters for a total of six, which was the maximum that could be accommodated. These were respectively designated Delta M6 or Delta N6. The first and only launch of the M6 configuration was Explorer 43 (IMP-H, Magnetospheric research) on 13 March 1971.[6] Three launches of the N6 between 1970 and 1971 resulted in one failure.[7]
The Delta 0100 series was the first stage of the initial numbered Delta was the Long Tank Thor, a version of the Thor missile with extended propellant tanks. Up to nine strap-on solid rocket boosters (SRBs) could be fitted. With three SRBs, the Delta was designated a 300 series, while the nine SRB variant was designated the 900 series. A new and improved Delta F second stage using the higher-thrust Aerojet AJ 10-118F engine was also introduced. The first 900 series launch was the fourth Delta 0100. On 23 July 1972, Thor-Delta 904 launched Landsat 1.[8] A license-built version of the Long Tank Thor stage with the MB-3 engine was also used for the Japanese N-I launch vehicle.
The Delta 1000 series was nicknamed the Straight-Eight and combined an Extended Long Tank first stage with an payload fairing, up to nine Castor 2 SRBs, and the new McDonnell Douglas Delta P second stage using the TRW TR-201 engine. Payload capacity increased to to LEO or to GTO. The first successful 1000 series Thor-Delta launched Explorer 47 on 22 September 1972.[8] The Extended Long Tank Thor stage was also used in the Japanese N-II and H-I launch vehicles.
The Delta 2000 introduced the new Rocketdyne RS-27 main engine on an Extended Long Tank first stage with the same constant 8-foot diameter. A Delta 2310 was the vehicle for the first three-satellite launch of NOAA-4, Intasat, and AMSAT-OSCAR 7 on 15 November 1974. Delta 2910 boosters were used to launch both Landsat 2 in 1975 and Landsat 3 in 1978. On 7 April 1978, a Delta 2914 launched "Yuri 1", the first Japanese BSE Broadcasting Satellite.[9]
The Delta 3000 combined the same first stage as 1000-series and 2000-series with upgraded Castor 4 solid boosters and was the last Delta series to use the McDonnell Douglas Delta P second stage with TRW TR-201 engine. Delta 3000 introduced the PAM (Payload Assist Module) / Star 48B solid-fueled kick motor, which was later used as Delta II third stage. The Delta 3914 model was approved for launching United States government payloads in May 1976[8] and was launched 13 times between 1975 and 1987.
The Delta 4000-series and 5000-series were developed in the aftermath of the Challenger disaster and consisted of a combination of 3000-era and Delta II-era components. The first stage had the MB-3 main engine and Extended Long Tank of the 3000-series and mounted upgraded Castor 4A motors. The new Delta K second stage was also included. A total of three were launched in 1989 and 1990, carrying two operational payloads.
The Delta 5000 series featured upgraded Castor 4A motors on an Extended Long Tank first stage with the new RS-27 main engine and only launched one mission.
Statistics are up-to-date .
| Number | Date/time (UTC) | Rocket | S/N | Launch site | Payload | Function | Orbit | Outcome | Remarks |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 1962-10-02 22:11:30 | Delta A | Thor 345 Delta 13 | CCAFS LC-17B | Explorer 14 | Magnetospheric | HEO | Maiden flight of Delta A | |
| 2 | 1962-10-27 23:15:01 | Delta A | Thor 346 Delta 14 | CCAFS LC-17B | Explorer 15 | Radiation | MEO | Final flight of Delta A | |
| 3 | 1962-12-13 23:30:01 | Delta B | Thor 355 Delta 15 | CCAFS LC-17A | Relay 1 | Communications | MEO | Maiden flight of Delta B | |
| 4 | 1963-02-14 05:35:08 | Delta B | Thor 358 Delta 16 | CCAFS LC-17B | Syncom 1 | Communications | GTO | Electronics failure on payload | |
| 5 | 1963-04-03 02:00:02 | Delta B | Thor 357 Delta 17 | CCAFS LC-17A | Explorer 17 | Atmospheric | LEO | ||
| 6 | 1963-05-07 11:38:03 | Delta B | Thor 366 Delta 18 | CCAFS LC-17B | Telstar 2 | Communications | MEO | ||
| 7 | 1963-06-19 09:50:01 | Delta B | Thor 359 Delta 19 | CCAFS LC-17B | TIROS-7 | Weather | SSO | ||
| 8 | 1963-07-26 14:33:00 | Delta B | Thor 370 Delta 20 | CCAFS LC-17A | Syncom 2 | Communications | GTO | ||
| 9 | 1963-11-27 02:30:01 | Delta C | Thor 387 Delta 21 | CCAFS LC-17B | Explorer 18 | Magnetospheric | HEO | Maiden flight of Delta C | |
| 10 | 1963-12-21 09:30:00 | Delta B | Thor 371 Delta 22 | CCAFS LC-17B | TIROS-8 | Weather | SSO | ||
| 11 | 1964-01-21 21:14:59 | Delta B | Thor 373 Delta 23 | CCAFS LC-17B | Relay 2 | Communications | MEO | ||
| 12 | 1964-03-19 11:13:41 | Delta B | Thor 391 Delta 24 | CCAFS LC-17A | BE-A | Ionospheric | LEO | Third stage underperformed | |
| 13 | 1964-08-19 12:15:02 | Delta D | Thor 417 Delta 25 | CCAFS LC-17A | Syncom 3 | Communications | GTO | ||
| 14 | 1964-10-04 03:45:00 | Delta C | Thor 392 Delta 26 | CCAFS LC-17A | Explorer 21 | Magnetospheric | HEO | Reached lower than planned orbit | |
| 15 | 1964-12-21 09:00:03 | Delta C | Thor 393 Delta 27 | CCAFS LC-17A | Explorer 26 | Magnetospheric | MEO | ||
| 16 | 1965-01-22 07:55 | Delta C | Thor 374 Delta 28 | CCAFS LC-17A | TIROS-9 | Weather Satellite | LEO / SSO | ||
| 17 | 1965-02-03 16:33 | Delta C | Thor 411 Delta 29 | CCAFS LC-17B | OSO-2 | Solar observation satellite | LEO | ||
| 18 | 1965-04-06 23:45 | Delta D | Thor 426 Delta 30 | CCAFS LC-17A | Intelsat I (Intelsat-1-1 / Early Bird) | Communication satellite | GTO | Performed first transcontinental satellite TV broadcast. | |
| 19 | 1965-05-29 12:00 | Delta C | Thor 441 Delta 31 | CCAFS LC-17B | Explorer 28 (IMP-C) | Interplanetary space research satellite | HEO | ||
| 20 | 1965-07-02 04:04 | Delta C | Thor 415 Delta 32 | CCAFS LC-17B | TIROS-10 | Weather Satellite | LEO / SSO | ||
| 21 | 1965-08-25 15:17 | Delta C | Thor 434 Delta 33 | CCAFS LC-17B | OSO-C | Solar observation satellite | planned: LEO | Third stage ignited while still attached to the second stage. | |
| 22 | 1965-11-06 18:43 | Delta E | Thor 457 Delta 34 | CCAFS LC-17A | Explorer 29 (GEOS-A) | Geodetic research satellite | MEO | ||
| 23 | 1965-12-16 07:31 | Delta E | Thor 460 Delta 35 | CCAFS LC-17A | Pioneer 6 | Interplanetary space research probe | Heliocentric | Probe continues to work as of late 2000. | |
| 24 | 1966-02-03 07:41 | Delta C | Thor 445 Delta 36 | CCAFS LC-17A | ESSA-1 | Weather Satellite | LEO / SSO | ||
| 25 | 1966-02-28 13:58 | Delta E | Thor 461 Delta 37 | CCAFS LC-17B | ESSA-2 | Weather Satellite | LEO / SSO | ||
| 26 | 1966-05-25 14:00 | Delta C1 | Thor 436 Delta 38 | CCAFS LC-17B | Explorer 32 (AE-B) | Atmospheric research Satellite | LEO | ||
| 27 | 1966-07-01 16:04 | Delta E1 | Thor 467 Delta 39 | CCAFS LC-17A | Explorer 33 (IMP-D) | Magnetosphere research Satellite | HEO | ||
| 28 | 1966-08-17 15:20 | Delta E1 | Thor 462 Delta 40 | CCAFS LC-17A | Pioneer 7 | Interplanetary space research probe | Heliocentric | ||
| 29 | 1966-10-02 10:34 | Delta E | Thor 463 Delta 41 | VAFB SLC-2E | ESSA-3 | Weather Satellite | LEO / SSO | First Delta launch from VAFB | |
| 30 | 1966-10-26 23:05 | Delta E1 | Thor 464 Delta 42 | CCAFS SLC-17B | Intelsat 2-1 | Communication Satellite | GTO | ||
| 31 | 1966-12-14 19:26 | Delta G | Thor 471 Delta 43 | CCAFS LC-17A | Biosatellite 1 | Life science research satellite | LEO | ||
| 32 | 1967-01-11 10:55 | Delta E1 | Thor 468 Delta 44 | CCAFS SLC-17B | Intelsat 2-2 | Communication Satellite | GTO | ||
| 33 | 1967-01-26 17:31 | Delta E | Thor 472 Delta 45 | VAFB SLC-2E | ESSA-4 | Weather Satellite | LEO / SSO | ||
| 34 | 1967-03-08 16:19 | Delta C | Thor 431 Delta 46 | CCAFS LC-17A | OSO-3 | Solar observation satellite | LEO | ||
| 35 | 1967-03-23 01:30 | Delta E1 | Thor 470 Delta 47 | CCAFS SLC-17B | Intelsat 2-3 | Communication Satellite | GTO | ||
| 36 | 1967-04-20 11:17 | Delta E | Thor 484 Delta 48 | VAFB SLC-2E | ESSA-5 | Weather Satellite | LEO / SSO | ||
| 37 | 1967-05-24 14:06 | Delta E1 | Thor 486 Delta 49 | VAFB SLC-2E | Explorer 34 (IMP-F) | Interplanetary space research satellite | HEO | ||
| 38 | 1967-07-19 14:19 | Delta E1 | Thor 488 Delta 50 | CCAFS SLC-17B | Explorer 35 (IMP-E) | Interplanetary space research satellite | Lunar Orbit | ||
| 39 | 1967-09-07 22:04 | Delta G | Thor 475 Delta 51 | CCAFS LC-17B | Biosatellite 2 | Life science research satellite | LEO | ||
| 40 | 1967-09-28 00:45 | Delta E1 | Thor 442 Delta 52 | CCAFS SLC-17B | Intelsat 2-4 | Communication Satellite | GTO | ||
| 41 | 1967-10-18 16:04 | Delta C | Thor 490 Delta 53 | CCAFS LC-17B | OSO-4 | Solar observation satellite | LEO | ||
| 42 | 1967-11-10 18:00 | Delta E1 | Thor 480 Delta 54 | VAFB SLC-2E | ESSA-6 | Weather Satellite | LEO / SSO | ||
| 43 | 1967-12-13 14:08 | Delta E1 | Thor 489 Delta 55 | CCAFS LC-17B | Pioneer 8 / TTS-1 | Interplanetary space research probe / Technology demonstration satellite | Heliocentric | ||
| 44 | 1968-01-11 16:19 | Delta E1 | Thor 454 Delta 56 | VAFB SLC-2E | Explorer 36 (GEOS-B) | Geodetic research satellite | LEO / SSO | ||
| 45 | 1968-07-04 17:31 | Delta J | Thor 476 Delta 57 | VAFB SLC-2E | Explorer 38 (RAE-A) | Radio astronomy satellite | MEO | ||
| 46 | 1968-08-16 11:31 | Delta N | Thor 528 Delta 58 | VAFB SLC-2E | ESSA-7 | Weather Satellite | LEO / SSO | Maiden Flight of the Long Tank Thor-Delta | |
| 47 | 1968-09-19 00:09 | Delta M | Thor 529 Delta 59 | CCAFS SLC-17A | Intelsat 3-1 | Communication Satellite | planned: GTO | Pitch gyroscope failure led to loss of control starting at T+20 seconds. RSO T+110 seconds. | |
| 48 | 1968-11-08 09:46 | Delta E1 | Thor 479 Delta 60 | CCAFS LC-17B | Pioneer 9 / TTS-2 | Interplanetary space research probe / Technology demonstration satellite | Heliocentric | ||
| 49 | 1968-12-05 18:55 | Delta E1 | Thor 481 Delta 61 | CCAFS LC-17B | HEOS-A | Magnetosphere research satellite | HEO | ||
| 50 | 1968-12-15 17:17 | Delta N | Thor 532 Delta 62 | VAFB SLC-2E | ESSA-8 | Weather Satellite | LEO / SSO | ||
| 51 | 1968-12-19 00:32 | Delta M | Thor 536 Delta 63 | CCAFS SLC-17A | Intelsat 3-2 | Communication Satellite | GTO | ||
| 52 | 1969-01-22 16:48 | Delta C1 | Thor 487 Delta 64 | CCAFS LC-17B | OSO-5 | Solar observation satellite | LEO | ||
| 53 | 1969-01-30 06:43 | Delta E1 | Thor 485 Delta 65 | VAFB SLC-2E | ISIS-I | Ionosphere research satellite | MEO | ||
| 54 | 1969-02-06 00:39 | Delta M | Thor 530 Delta 66 | CCAFS SLC-17A | Intelsat 3-3 | Communication Satellite | GTO | ||
| 55 | 1969-02-26 07:47 | Delta E1 | Thor 483 Delta 67 | CCAFS SLC-17B | ESSA-9 | Weather Satellite | LEO / SSO | ||
| 56 | 1969-05-22 02:00 | Delta M | Thor 533 Delta 68 | CCAFS SLC-17A | Intelsat 3-4 | Communication Satellite | GTO | ||
| 57 | 1969-06-21 08:53 | Delta E1 | Thor 482 Delta 69 | VAFB SLC-2W | Explorer 41 (IMP-G) | Interplanetary space research satellite | HEO | ||
| 58 | 1969-06-29 13:26 | Delta N | Thor 539 Delta 70 | CCAFS SLC-17A | Biosatellite 3 | Life science research satellite | LEO | ||
| 59 | 1969-07-26 02:06 | Delta M | Thor 547 Delta 71 | CCAFS SLC-17A | Intelsat 3-5 | Communication Satellite | planned: GTO | Stage 3 motor case ruptured, leaving spacecraft in unusable orbit | |
| 60 | 1969-08-09 07:32 | Delta N | Thor 548 Delta 72 | CCAFS LC-17A | OSO-6 / PAC-1 | Solar observation satellite / Technology test | GTO | ||
| 61 | 1969-08-27 21:59 | Delta L | Thor 540 Delta 73 | CCAFS LC-17A | Pioneer E / TTS-3 | Interplanetary space research probe / Technology demonstration satellite | planned: Heliocentric | Defective valve in Stage 1 caused a hydraulic fluid leak and loss of engine gimbaling at T+220 seconds, making it impossible for the second stage to reach orbit. RSO T+480 seconds. | |
| 62 | 1969-11-22 00:37 | Delta M | Thor 554 Delta 74 | CCAFS SLC-17A | Skynet 1A | Military communication Satellite | GTO | ||
| 63 | 1970-01-15 00:16 | Delta M | Delta 75 Thor 557 | CCAFS SLC-17A | Intelsat 3-6 | Communication satellite | GTO | ||
| 64 | 1970-01-23 11:52 | Delta N6 | Delta 76 Thor 542 | VAFB SLC-2W | ITOS 1 / Oscar 5 | Weather Satellite / Amateur radio satellite | LEO / SSO | ||
| 65 | 1970-03-20 23:46 | Delta M | Delta 77 Thor 558 | CCAFS SLC-17A | NATO 1 | Military communication satellite | GTO | ||
| 66 | 1970-04-23 00:46 | Delta M | Delta 78 Thor 559 | CCAFS SLC-17A | Intelsat 3-7 | Communication satellite | GTO | ||
| 67 | 1970-07-23 23:23 | Delta M | Delta 79 Thor 563 | CCAFS SLC-17A | Intelsat 3-8 | Communication satellite | GTO | ||
| 68 | 1970-08-19 12:11 | Delta M | Delta 80 Thor 561 | CCAFS SLC-17A | Skynet-1B | Military communication satellite | GTO | ||
| 69 | 1970-12-11 11:35 | Delta N6 | Delta 81 Thor 546 | VAFB SLC-2W | NOAA-1 | Weather Satellite | LEO / SSO | ||
| 80 | 1971-02-03 01:41 | Delta M | Delta 82 Thor 560 | CCAFS SLC-17A | NATO 2 | Military communication satellite | GTO | ||
| 71 | 1971-03-13 16:15 | Delta M6 | Delta 83 Thor 562 | CCAFS SLC-17A | Explorer 43 (IMP-H) | Magnetosphere research satellite | HEO | ||
| 72 | 1971-04-01 02:53 | Delta E1 | Delta 84 Thor 491 | VAFB SLC-2E | ISIS-II | Ionosphere research satellite | LEO / SSO | ||
| 73 | 1971-09-29 09:50 | Delta N | Delta 85 Thor 565 | CCAFS SLC-17A | OSO 7 / TTS-4 | Solar observation satellite / Technology demonstration | LEO, 321×572 km, 93.2 min, i=33.1°, e=0.0184 | 2nd stage suffered a failure of the attitude control system, however the satellite reached orbit and ground controllers were able to correct its flight path.[10] | |
| 74 | 1971-10-21 11:32 | Delta N6 | Delta 86 Thor 572 | VAFB SLC-2E | ITOS-B | Weather Satellite | planned: LEO / SSO | 2nd stage oxidizer leak starting at T+20 seconds. The attitude control system ran out of propellant trying to correct the stage's flight path and the launch vehicle reentered the atmosphere and broke up above the Arctic Circle. | |
| 75 | 1972-01-31 17:20 | Delta L | Delta 87 Thor 564 | VAFB SLC-2E | HEOS-2 | Magnetosphere research satellite | HEO | ||
| 76 | 1972-03-12 00:00 | Delta N | Delta 88 Thor 573 | VAFB SLC-2E | TD-1A | Astronomical research satellite | LEO / SSO | ||
| 77 | 1972-07-23 18:06 | Delta 904[11] | Delta 89 Thor 574 | VAFB SLC-2W | Landsat 1 | Earth Resource Technology Satellite | 917 km LEO, near polar, Sun synchronous. | First use of 9 strap-on SRBs. Discovered Landsat Island. | |
| 78 | 1972-09-23 13:20 | Delta 1604 | Delta 90 Thor 579 | CCAFS SLC-17B | Explorer 47 (IMP-I) | Magnetospheric research satellite | HEO | First successful flight of Delta-1000 series. | |
| 79 | 15 October 1972 17:17 | Delta 300 | Delta 91 Thor 575 | VAFB, SLC-2W | NOAA-2 / AMSAT-OSCAR 6 | Weather satellite / Amateur radio satellite | LEO / SSO | ||
| 80 | 1972-11-10 01:14 | Delta 1914 | Delta 92 Thor 580 | CCAFS SLC-17B | Anik-A1 | Communication Satellite | GTO | ||
| 81 | 1972-12-11 07:56 | Delta 900 | Delta 93 Thor 577 | VAFB SLC-2W | Nimbus-5 | Weather Satellite | LEO / SSO | ||
| 82 | 1973-04-20 23:47 | Delta 1914 | Delta 94 Thor 583 | CCAFS SLC-17B | Anik-A2 | Communication Satellite | GTO | ||
| 83 | 1973-06-10 14:13 | Delta 1913 | Delta 95 Thor 581 | CCAFS SLC-17B | Explorer 49 (RAE-B) | Radio astronomy satellite | Lunar Orbit | ||
| 84 | 1973-07-16 17:10 | Delta 300 | Delta 96 Thor 578 | VAFB SLC-2W | ITOS-E | Weather Satellite | planned: LEO / SSO | Hydraulic pump malfunction led to failure of the 2nd stage attitude control system. The booster and payload reentered the atmosphere and broke up. | |
| 85 | 1973-10-26 02:26 | Delta 1604 | Delta 97 Thor 582 | CCAFS SLC-17B | Explorer 50 (IMP-J) | Magnetospheric research satellite | HEO | ||
| 86 | 1973-11-06 14:02 | Delta 300 | Delta 98 Thor 576 | VAFB SLC-2W | NOAA-3 | Weather Satellite | LEO / SSO | ||
| 87 | 1973-12-16 06:18 | Delta 1900 | Delta 99 Thor 585 | VAFB SLC-2W | Explorer 51 (AE-C) | Atmospheric research satellite | MEO | ||
| 88 | 1974-01-19 01:38 | Delta 2313 | Delta 100 Thor 587 | CCAFS SLC-17B | Skynet-2A | Military communication satellite | planned: GTO | First flight of the Delta 2000 series. Stage 2 electronics package short circuited (induced by a piece of conductive contaminant shaken loose during launch), leading to loss of control. | |
| 89 | 1974-04-13 21:33 | Delta 2914 | Delta 101 Thor 588 | CCAFS SLC-17B | Westar-1 | Communication satellite | GTO | ||
| 90 | 1974-05-17 10:31 | Delta 2914 | Delta 102 Thor 590 | CCAFS SLC-17B | SMS-1 | Weather satellite | GTO | ||
| 91 | 1974-10-10 22:53 | Delta 2914 | Delta 103 Thor 589 | CCAFS SLC-17B | Westar-2 | Communication satellite | GTO | ||
| 92 | 1974-11-15 17:11 | Delta 2310 | Delta 104 Thor 592 | VAFB SLC-2W | NOAA-4 / Oscar 7 / Intasat | Weather Satellite / Amateur radio satellite / Ionosphere research | LEO / SSO | ||
| 93 | 1974-11-23 00:28 | Delta 2313 | Delta 105 Thor 591 | CCAFS SLC-17B | Skynet-2B | Military communication satellite | GTO | ||
| 94 | 1974-12-19 02:39 | Delta 2914 | Delta 106 Thor 599 | CCAFS SLC-17B | Symphonie-1 | Communication satellite | GTO | ||
| 95 | 1975-01-22 17:56 | Delta 2910 | Delta 107 Thor 598 | VAFB SLC-2W | Landsat 2 | Earth Resource Technology Satellite | 917 km LEO, near polar, Sun synchronous. | Satellite operated until Feb 25, 1982. | |
| 96 | 1975-02-06 22:04 | Delta 2914 | Delta 108 Thor 593 | CCAFS SLC-17B | SMS-2 | Weather satellite | GTO | ||
| 97 | 1975-04-10 23:50 | Delta 1410 | Delta 109 Thor 584 | VAFB SLC-2W | GEOS-C | Geodetic research satellite | LEO | ||
| 98 | 1975-05-07 23:35 | Delta 2914 | Delta 110 Thor 596 | CCAFS SLC-17B | Anik-A3 | Communication Satellite | GTO | ||
| 99 | 1975-06-12 08:12 | Delta 2910 | Delta 111 Thor 595 | VAFB SLC-2W | Nimbus-6 | Weather Satellite | LEO / SSO | ||
| 100 | 1975-06-21 11:43 | Delta 1910 | Delta 112 Thor 586 | CCAFS SLC-17B | OSO-8 | Solar observation satellite | LEO | ||
| 101 | 1975-08-09 01:47 | Delta 2913 | Delta 113 Thor 602 | VAFB SLC-2W | COS-B | High-energy astronomy research satellite | HEO | ||
| 102 | 1975-08-27 01:42 | Delta 2914 | Delta 114 Thor 594 | CCAFS SLC-17A | Symphonie-2 | Communication satellite | GTO | ||
| 103 | 1975-10-06 09:01 | Delta 2910 | Delta 115 Thor 600 | VAFB SLC-2W | Explorer 54 (AE-D) | Atmospheric research satellite | MEO | ||
| 104 | 1975-10-16 22:40 | Delta 2914 | Delta 116 Thor 597 | CCAFS SLC-17B | GOES-A (GOES-1) | Weather satellite | GTO | ||
| 105 | 1975-11-20 02:06 | Delta 2910 | Delta 117 Thor 604 | CCAFS SLC-17B | Explorer 55 (AE-E) | Atmospheric research satellite | MEO | ||
| 106 | 1975-12-13 01:56 | Delta 3914 | Delta 118 Thor 607 | CCAFS SLC-17A | Satcom-1 | Communication satellite | GTO | First flight of the Delta 3000 series. | |
| 107 | 1976-01-17 23:28 | Delta 2914 | Delta 119 Thor 606 | CCAFS SLC-17B | CTS 1 Hermes | Experimental communication satellite | GTO | ||
| 108 | 1976-02-19 22:32 | Delta 2914 | Delta 120 Thor 603 | CCAFS SLC-17B | Marisat-1 | Communication satellite | GTO | ||
| 109 | 1976-03-26 22:42 | Delta 3914 | Delta 121 Thor 610 | CCAFS SLC-17A | Satcom-2 | Communication satellite | GTO | ||
| 110 | 1976-04-22 20:46 | Delta 2914 | Delta 122 Thor 608 | CCAFS SLC-17B | NATO 3A | Military communication satellite | GTO | ||
| 111 | 1976-05-04 08:00 | Delta 2913 | Delta 123 Thor 609 | VAFB SLC-2W | LAGEOS-1 | Geodesic research satellite | MEO | ||
| 112 | 1976-06-10 00:09 | Delta 2914 | Delta 124 Thor 601 | CCAFS SLC-17A | Marisat-2 | Communication satellite | GTO | ||
| 113 | 1976-07-08 23:31 | Delta 2914 | Delta 125 Thor 611 | CCAFS SLC-17A | Palapa-A1 | Communication satellite | GTO | ||
| 114 | 1976-07-29 17:07 | Delta 2310 | Delta 126 Thor 605 | VAFB SLC-2W | NOAA-5 | Weather satellite | LEO / SSO | ||
| 115 | 1976-10-14 22:44 | Delta 2914 | Delta 127 Thor 614 | CCAFS SLC-17A | Marisat-3 | Communication satellite | GTO | ||
| 116 | 1977-01-28 00:49 | Delta 2914 | Delta 128 Thor 613 | CCAFS SLC-17A | NATO 3B | Military communication satellite | GTO | ||
| 117 | 1977-03-10 23:16 | Delta 2914 | Delta 129 Thor 612 | CCAFS SLC-17A | Palapa-A2 | Communication satellite | GTO | ||
| 118 | 1977-04-20 10:15 | Delta 2914 | Delta 130 Thor 617 | CCAFS SLC-17B | ESA-GEOS-1 | Magnetosphere research satellite | planned: GTO | Premature separation of second and third stages led to failure of Stage 3 spin up. | |
| 119 | 1977-06-16 10:51 | Delta 2914 | Delta 131 Thor 616 | CCAFS SLC-17B | GOES-B (GOES-2) | Weather satellite | GTO | ||
| 120 | 1977-07-14 14:56 | Delta 2914 | Delta 132 Thor 618 | CCAFS SLC-17B | GMS-1 | Weather satellite | GTO | ||
| 121 | 1977-08-25 23:50 | Delta 2313 | Delta 133 Thor 615 | CCAFS SLC-17B | Sirio-1 | Experimental communication satellite | GTO | ||
| 122 | 1977-09-13 23:21 | Delta 3914 | Delta 134 Thor 619 | CCAFS SLC-17A | OTS-1 | Experimental communication satellite | planned: GTO | Launch vehicle exploded at T+52 seconds due to a rupture of the SRM #1 casing. | |
| 123 | 1977-10-22 13:53 | Delta 2914 | Delta 135 Thor 623 | CCAFS SLC-17B | Explorer 56 (ISEE-A / B) | Magnetospheric research satellites | HEO | ||
| 124 | 1977-11-23 01:35 | Delta 2914 | Delta 136 Thor 620 | CCAFS SLC-17A | Meteosat-1 | Weather satellite | GTO | ||
| 125 | 1977-12-15 00:47 | Delta 2914 | Delta 137 Thor 624 | CCAFS SLC-17B | CS-1 | Experimental communication satellite | GTO | ||
| 126 | 1978-01-26 17:36 | Delta 2914 | Delta 138 Thor 613 | CCAFS SLC-17A | Explorer 57 (International Ultraviolet Explorer) | Astronomical observatory satellite | HEO | Satellite operational until 1996. | |
| 127 | 1978-03-05 17:54 | Delta 2910 | Delta 139 Thor 621 | VAFB SLC-2W | Landsat 3 OSCAR 8 | Earth Resource Technology Satellite | 917 km LEO, near polar, Sun synchronous. | Satellite decommissioned on March 21, 1983. | |
| 128 | 7 April 1978 22:01 | Delta 2914 | Delta 140 Thor 626 | CCAFS, SLC-17B | BSE-1[12] | Direct-broadcast satellite | GTO | First of Japanese BSE series, also known as "Yuri 1". | |
| 129 | 1978-05-11 22:59 | Delta 3914 | Delta 141 Thor 627 | CCAFS SLC-17A | OTS-2 | Experimental communication satellite | GTO | ||
| 130 | 1978-06-16 10:49 | Delta 2914 | Delta 142 Thor 625 | CCAFS SLC-17B | GOES-C (GOES-3) | Weather satellite | GTO | ||
| 131 | 1978-07-14 10:43 | Delta 2914 | Delta 143 Thor 631 | CCAFS SLC-17A | ESA-GEOS-2 | Magnetosphere research satellite | GTO | ||
| 132 | 1978-08-12 15:12 | Delta 2914 | Delta 144 Thor 633 | CCAFS SLC-17B | Explorer 59 (ISEE-3) | Magnetospheric research satellite | HEO to Sun-Earth L1 halo orbit Eventually shifted to heliocentric | First satellite to use Lagrangian point and halo orbit Later re-classified as the International Cometary Explorer. Satellite still operational as of 2014.[13] | |
| 133 | 1978-10-24 08:14 | Delta 2910 | Delta 145 Thor 630 | VAFB SLC-2W | Nimbus-7 / CAMEO | Weather Satellite / Ionosphere research | LEO / SSO | ||
| 134 | 1978-11-19 00:46 | Delta 2914 | Delta 146 Thor 634 | CCAFS SLC-17B | NATO 3C | Military communication satellite | GTO | ||
| 135 | 1978-12-16 00:21 | Delta 3914 | Delta 147 Thor 632 | CCAFS SLC-17A | Anik-B1 | Communication Satellite | GTO | ||
| 136 | 1979-01-30 21:42 | Delta 2914 | Delta 148 Thor 629 | CCAFS SLC-17B | SCATHA (P78-2) | Military technological research satellite | HEO | ||
| 137 | 1979-08-10 00:20 | Delta 2914 | Delta 149 Thor 638 | CCAFS SLC-17A | Westar-3 | Communication Satellite | GTO | ||
| 138 | 1979-12-07 01:35 | Delta 3914 | Delta 150 Thor 622 | CCAFS SLC-17A | Satcom-3 | Communication satellite | GTO | ||
| 139 | 1980-02-14 15:57 | Delta 3910 | 151 (Thor 635) | CCAFS LC-17A | Solar observation satellite | LEO | |||
| 140 | 1980-09-09 22:27 | Delta 3914 | 152 (Thor 637) | CCAFS LC-17A | GOES-D (GOES-4) | Weather satellite | GTO | ||
| 141 | 1980-11-15 22:49 | Delta 3910 | 153 (Thor 636) | CCAFS LC-17A | SBS-1 | Communications satellite | GTO | ||
| 142 | 1981-05-22 22:29 | Delta 3914 | 154 (Thor 645) | CCAFS LC-17A | GOES-E (GOES-5) | Weather Satellite | GTO | ||
| 143 | 1981-08-03 09:56 | Delta 3913 | 155 (Thor 642) | VAFB LC-2W | Explorer 62 / 63 (Dynamics Explorer-A/B) | Magnetosphere research satellites | MEO | ||
| 144 | 1981-09-24 23:09 | Delta 3910 | 156 (Thor 641) | CCAFS LC-17A | SBS-2 | Communications satellite | GTO | ||
| 145 | 1981-10-06 11:27 | Delta 2310 | 157 (Thor 639) | CCAFS LC-17A | Explorer 64 (Solar Mesosphere Explorer) / Oscar-9 | Atmospheric research satellite / amateur radio satellite | LEO | ||
| 146 | 1981-11-20 01:37 | Delta 3910 | 158 (Thor 640) | CCAFS LC-17A | Satcom 3R | Communications satellite | GTO | ||
| 147 | 1982-01-16 01:54 | Delta 3910 | 159 (Thor 643) | CCAFS LC-17A | Satcom 4 | Communications satellite | GTO | ||
| 148 | 1982-02-26 00:04 | Delta 3910 | 160 (Thor 644) | CCAFS LC-17A | Westar 4 | Communications satellite | GTO | ||
| 149 | 1982-04-10 06:47 | Delta 3910 | 161 (Thor 647) | CCAFS LC-17A | Insat 1A | Communications satellite | GTO | ||
| 150 | 1982-06-09 00:24 | Delta 3910 | 162 (Thor 649) | CCAFS LC-17A | Westar 5 | Communications satellite | GTO | ||
| 151 | 1982-07-16 17:59 | Delta 3920 | 163 (Thor 648) | VAFB LC-2W | Landsat 4 | Earth observation satellite | LEO | ||
| 152 | 1982-08-26 23:10 | Delta 3920 | 164 (Thor 651) | CCAFS LC-17B | Anik D1 | Communications satellite | GTO | ||
| 153 | 1982-10-28 01:27 | Delta 3924 | 165 (Thor 652) | CCAFS LC-17B | Satcom 5 | Communications satellite | GTO | ||
| 154 | 1983-01-25 02:17 | Delta 3910 | 166 (Thor 650) | VAFB LC-2W | IRAS / PIX-2 | Infrared Space telescope / Technological research | LEO | ||
| 155 | 1983-04-11 22:39 | Delta 3924 | 167 (Thor 653) | CCAFS LC-17B | Satcom 6 | Communications satellite | GTO | ||
| 156 | 1983-04-28 22:26 | Delta 3914 | 168 | CCAFS LC-17A | GOES-F (GOES-6) | Weather Satellite | GTO | ||
| 157 | 1983-05-26 15:18 | Delta 3914 | 169 | VAFB LC-2W | EXOSAT | X-ray Space telescope | HEO | ||
| 158 | 1983-06-28 23:08 | Delta 3920 | 170 | CCAFS LC-17B | Galaxy 1 | Communications satellite | GTO | ||
| 159 | 1983-07-28 22:49 | Delta 3920 | 171 | CCAFS LC-17A | Telstar-3A | Communications satellite | GTO | ||
| 160 | 1983-09-08 22:52 | Delta 3920 | 172 | CCAFS LC-17B | Satcom 7 | Communications satellite | GTO | ||
| 161 | 1983-09-22 22:16 | Delta 3920 | 173 | CCAFS LC-17A | Galaxy 2 | Communications satellite | GTO | ||
| 162 | 1984-03-01 17:59 | Delta 3920 | 174 | VAFB LC-2W | Landsat 5 / Oscar-11 | Earth observation satellite / Amateur radio satellite | LEO | ||
| 163 | 1984-08-16 14:30 | Delta 3924 | 175 | CCAFS LC-17A | Explorer 65 (Active Magnetospheric Particle Tracer Explorers-1/2/3) | Magnetosphere research satellites | HEO | ||
| 164 | 1984-09-21 22:18 | Delta 3920 | 176 | CCAFS LC-17B | Galaxy-3 | Communications satellite | GTO | ||
| 165 | 1984-11-14 00:34 | Delta 3914 | 177 | CCAFS LC-17A | NATO-3D | Military communications satellite | GTO | ||
| 166 | 1986-05-03 22:18 | Delta 3914 | 178 | CCAFS LC-17A | GOES-G | Weather Satellite | planned: GTO | Electric failure in first stage caused the rocket to lose control and was destroyed 90 seconds into flight | |
| 167 | 1986-09-05 15:08 | Delta 3920 | 180 | CCAFS LC-17B | Vector Sum Experiment (USA-19) | Experimental on-orbit ASAT test satellite | LEO | ||
| 168 | 1987-02-26 23:05 | Delta 3914 | 179 | CCAFS LC-17A | GOES-H (GOES-7) | Weather Satellite | GTO | ||
| 169 | 1987-03-20 22:22 | Delta 3920 | 182 | CCAFS LC-17B | Palapa B2P | Communications satellite | GTO | ||
| 170 | 1988-02-08 22:07 | Delta 3910 | 181 | CCAFS LC-17B | Thrusted Vector Experiment (USA-30) | Experimental on-orbit ASAT test satellite | LEO | ||
| 171 | 1989-03-24 21:50 | Delta 3920-8 | 183 | CCAFS LC-17B | Delta Star (USA-36) | Experimental on-orbit ASAT test satellite | LEO | ||
| 172 | 1989-08-27 22:59 | Delta 4925-8 http://www.boeing.com/defense-space/space/bls/missions/index.html | 187 | CCAFS LC-17B | BSB-R1 (Marcopolo 1) | Communications satellite | GTO | ||
| 173 | 1989-11-18 14:34 | Delta 5920-8 http://www.boeing.com/defense-space/space/bls/missions/index.html | 189 | VAFB LC-2W | COBE | Cosmology observation satellite | LEO[14] | ||
| 174 | June 12, 1990 05:52 | Delta 4925-8 | CCAFS LC-17B | INSAT 1D | Comsat | GTO | Comsat, Last Delta I launch | ||
At least eight Delta rockets have contributed orbital debris in the Sun-synchronous low Earth orbit environment. The variant of the Delta upper stage that was used in the 1970s was found to be prone to in-orbit explosions. Starting in 1981, depletion burns to get rid of excess propellant became standard, and no Delta Rocket Bodies launched after 1981 experience severe fragmentations afterward, but some of those launched prior to 1981 continued to explode. In 1991, the Delta 1975-052B fragmented, 16 years after launch, demonstrating the resilience of the propellant.
In 2017, Delta 1 Rocket Body 1968-114B, using an earlier less fragmentation-prone upper stage, fragmented into 17 pieces, nearly 50 years after launch. Though one possibility is that this rocket body exploded, the signature of the debris cloud is more indicative of a low-energy collision.[15]