About the Delta DM-19 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.
The first stage was a Thor missile in the DM-19 configuration. The second stage was the Delta, which had been derived from the earlier Able stage. An Altair solid rocket motor was used as a third stage.
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.
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 statistics Launch outcome
Launchpad
Orbit
Function
Launch history Date/time(UTC)RocketS/NLaunch sitePayloadFunctionOrbitOutcomeRemarks1960-05-1309:16:05Thor DM-19 DeltaThor 144Delta 1CCAFS LC-17AEcho 1CommunicationMEO Maiden flight of Thor-Delta, upper-stage attitude control system malfunctioned1960-08-1209:39:43Thor DM-19 DeltaThor 270Delta 2CCAFS LC-17AEcho 1ACommunicationsMEO 1960-11-2311:13:03Thor DM-19 DeltaThor 245Delta 3CCAFS LC-17ATIROS-2WeatherSSO 1961-03-2515:17:04Thor DM-19 DeltaThor 295Delta 4CCAFS LC-17AExplorer 10MagnetosphericHEO 1961-07-1210:25:06Thor DM-19 DeltaThor 286Delta 5CCAFS LC-17ATIROS-3WeatherSSO 1961-08-1603:21:05Thor DM-19 DeltaThor 312Delta 6CCAFS LC-17AExplorer 12MagnetosphericHEO 1962-02-0812:43:45Thor DM-19 DeltaThor 317Delta 7CCAFS LC-17ATIROS-4WeatherSSO 1962-03-0716:06:18Thor DM-19 DeltaThor 301Delta 8CCAFS LC-17AOSO-1SolarLEO 1962-04-2618:00:16Thor DM-19 DeltaThor 320Delta 9CCAFS LC-17AAriel 1IonosphericLEO 1962-06-1912:19:01Thor DM-19 DeltaThor 321Delta 10CCAFS LC-17ATIROS-5WeatherSSO 1962-07-1008:35:05Thor DM-19 DeltaThor 316Delta 11CCAFS LC-17BTelstar 1CommunicationMEO 1962-09-1808:53:08Thor DM-19 DeltaThor 318Delta 12CCAFS LC-17ATIROS-6WeatherSSO Final flight of Thor-Delta
See also List of Delta 4 launches List of Thor and Delta launches List of Thor and Delta launches (1960–1969) List of Delta IV Heavy launches List of Delta IV Medium launches Thor-Delta
References