The Aug. 2, 1993, explosion marked the first failure of a Titan 4.

The accident occurred

a mere 101 seconds

following launch after a hole burned through one of its solid-rocket motors.

The loss cost the Navy three of its ocean surveillance satellites, according to a story first published in the

Aug. 4 edition of the New York Times

and later confirmed

by Space News.

It would not be the last failure for the Titan 4: four rockets failed in 1998 and 1999, three times in succession. The failures and high

cost of the

Titan 4


eventually spelled the end of the Titan line, which served the United States for five decades.

The heavy-lift rockets were used almost exclusively for launching the largest and costliest of

U.S. military payloads, including the National Reconnaissance Office’s (NRO) imaging and intelligence satellites and Air Force missile warning satellites.

The 60-meter tall Titan 4 was conceived in the 1980s as an alternative to using the space shuttle for launching military satellites. In 1985 Edward “Pete” Aldridge, the Air Force secretary and NRO director, who is credited as being the person largely responsible for the Titan 4, ordered 10 of the rockets. The decision proved fortuitous when

the Space Shuttle Challenger exploded soon after liftoff Jan. 28, 1986, which led to the suspension of

shuttle launches for the next 22 months.

The first Titan 4 was

launched June 14, 1989.

“The fact is, after the Challenger disaster occurred, were it not for Aldridge’s desire for 10 Titan 4s, our national security space program would have ground to a halt,” Peter B. Teets, former undersecretary of the Air Force and NRO director said in an interview published in the Oct. 24, 2005, issue of Space News.

Built by Martin Marietta – now Bethesda-based Lockheed Martin – the Titan family began as a two-stage ICBM. The Titan 2 made the transition from an ICBM to a rocket booster for the NASA Gemini manned spacecraft and weather satellites.

But the heavy-lift Titan 4 version of the rocket fell out of favor

after the end of the Cold War and amid concern in Congress and the Air Force about its



. Fewer launches meant even higher rocket production prices for what was by then

the most expensive of the United States’ expendable rockets.

Its high cost was a big reason the Air Force initiated the Evolved Expendable Launch Vehicle program, which uses common hardware parts to save costs especially for heavy launches.

The last Titan 4 – and the last in the Titan series – successfully launched Oct. 19, 2005, from Vandenberg Air Force Base, Calif.