Date
.
June 26, 1970
NASA awarded McDonnell Douglas a
contract to incorporate the new Delta inertial guidance
system into the Thor-Delta vehicle.
Oct. 13, 1971
Details of the improved 2000 series
Thor-Delta were discussed with representatives of potential
user organizations.
March 11, 1972
The first Thor-Delta with a Universal
Boat Tail was launched (TD-IA); the boat tail allowed the
addition of up to nine strap-on solid rocket motors.
July 23, 1972
The launch of Landsat I marked the
first use of nine strap-one and the new uprated second-stage
engine (AJ 10-118F). This Thor-Delta model was designated
the 904.
Sept. 22, 1972
With the launch of Explorer 47, the
first 1000 series Thor-Delta was proven successful.
Nov. 15, 1974
For the first time, a Thor-Delta
launched three satellites simultaneously (NOAA 4, Intesat,
and Amsat Oscar 7).
May 7, 1975
The launch of Anik 3 marked the 100th
successful Delta liftoff.
Spring 1976
NASA officials studied the
possibility of using a Delta-class (TE 364) stage instead of
the Air Force-sponsored Interim Upper Stage for use with
Shuttle payloads.
May 1976
The U.S. Aeronautics and Astronautics
Control Board, made up of NASA and Department of Defense
personnel, approved the Delta 3914 model for government
use.
Nov. 23, 1976
NASA Headquarters plans called for
Delta to be phased out at the Kennedy Space Center during
1980 in anticipation of the Space Transportation System
becoming operational.