Thor-Delta

{{Short description|Expendable Rocket developed by USA during the Cold War to launch satellites}}

{{Use American English|date=November 2021}}

{{Use dmy dates|date=November 2021}}

{{Infobox Rocket

| image = 19620426 Delta 9-Ariel 1 LC-17A.jpg

| caption = Thor 320 Delta 9 rocket with UK first satellite Ariel 1, 26 April 1962

| upright = 1

| function = Expendable launch system

| country-origin = United States

| sites = Cape Canaveral, LC-17

| launches = 12

| success = 11

| fail = 1

| status = Retired

| first = 13 May 1960

| last = 18 September 1962

|stage1engines=DM-18A / MB-3-I|stage2engines=AJ-10-142|stage3aengines=X-248A-7|stage1name=Thor DM-19|stage2name=Delta|stage3name=Altair|LEO-payload=270 kg}}

The Thor-Delta, also known as Delta DM-19 or just Delta was an early American expendable launch system used for 12 orbital launches in the early 1960s. A derivative of the Thor-Able, it was a member of the Thor family of rockets, and the first member of the Delta family.{{cite web|url=http://www.astronautix.com/lvs/delta.htm |title=Delta|last=Wade|first=Mark|publisher=Encyclopedia Astronautica|access-date=2009-02-09|url-status=dead|archive-url=https://web.archive.org/web/20130817180906/http://astronautix.com/lvs/delta.htm |archive-date=2013-08-17}}

The first stage was a Thor missile in the DM-19 configuration (DM-18A / MB-3-I engine). The second stage was the Delta (AJ-10-142 engine), which had been derived from the earlier Able stage. An Altair solid rocket motor (X-248A-7) was used as a third stage.{{cite web|url=http://space.skyrocket.de/doc_lau_fam/thor.htm|title=Thor family|publisher=Gunter's Space Page |access-date=2009-02-09}}{{Cite web |title=Delta |url=https://space.skyrocket.de/doc_lau_det/delta.htm |access-date=2024-11-29 |website=Gunter's Space Page |language=en}}

The basic design of the original Vanguard upper stages, featuring a pressure-fed nitric acid/UDMH, regeneratively cooled engine, was kept in place, but with an improved AJ10-118 engine. More significantly, the Delta stage featured cold gas attitude control jets allowing it to be stabilized in orbit for restart and more precise burns.

The Thor-Delta was the first rocket to use the combination of a Thor missile and a Delta upper stage. This configuration was reused for many later rockets, and a derivative, the Delta II, remained in service until 2018.

Thor-Delta launches

The Thor-Delta launched a number of significant payloads, including the first communications satellite, Echo 1A; the first British satellite, Ariel 1; and the first active direct-relay communications satellite, Telstar 1. All 12 launches occurred from Cape Canaveral Air Force Station Launch Complex 17. The launch of Telstar 1 used pad B, while all other launches were from pad A. All launches were successful except the maiden flight, which failed to place Echo 1 into orbit due to a problem with the second stage.

= Launch list =

{{see also|List of Thor and Delta launches (1960–1969)}}{{transcluded section|source=List of Delta DM-19 launches}}

{{#section-h:List of Delta DM-19 launches|Launch history}}

Gallery

File:Launch of TIROS II Spac0047-repair.jpg|Thor 245 Delta 3 launching TIROS-2

File:Thor-Delta TIROS III launch.jpg|Thor 286 Delta 5 launching TIROS-3

File:Thor Delta with Explorer 10 (Mar. 25, 1961).gif|Thor 295 Delta 4 launching Explorer 10

File:Thor Delta with Telstar 1 Jul 10 1962.jpg|Thor 316 Delta 11 launching Telstar 1

File:Thor Delta with Tiros 4 (Feb. 8 1962)-repair.jpg|Thor 317 Delta 7 launching TIROS-4

File:Thor Delta with Ariel 1 (Apr. 26, 1962).jpg|Thor 320 Delta 9 launching Ariel 1

See also

{{Portal|Spaceflight}}

References

{{Reflist}}

{{Expendable launch systems}}

{{US launch systems}}

{{Thor and Delta rockets}}

Category:Thor (rocket family)