KH-4B 10 (Corona 138) & Tripos 4

Launch Success

Liftoff Time (GMT)

21:35:00

Wednesday May 20, 1970

Mission Details

KH-4B 10 (Corona 138)

The KH-4B (Keyhole-4B) marked the sixth iteration within the Corona program for optical reconnaissance satellites. It was equipped with two J-3 panoramic cameras, each with a focal length of 61 cm, providing a ground resolution of 1.8 meters and a ground swath of 16 km × 217 km. Additionally, the KH-4B featured the DISIC (Dual Improved Stellar Index) camera, offering superior mapping capabilities compared to the KH-5 Argon system. The DISIC camera had a focal length of 91 cm, providing a ground resolution of 30 meters, with a frame coverage of 260 km × 260 km.

Tripos 4

The Tripos Sousea satellites were part of a series of so called Program 11 or P-11 "Subsatellite Ferrets", low orbit ELINT/SIGINT satellites to pinpoint and characterize different Radar emitters in the Soviet Union and Warsaw pact states.

Rocket

Retired
Thorad SLV-2G Agena-D

Active 1966 to 1972


Rocket

Height: 31m

Liftoff Thrust

1,571 Kilonewtons

Stages

2

Strap-ons

3

Launch Site

SLC-3W

Vandenberg SFB, California, USA

Fastest Turnaround

17 days 21 hours

Stats

Thor-Agena


174th

Mission

4th

Mission of 1970

1970


42nd

Orbital launch attempt