Manned Spaceflight Engineer Program The Manned Spaceflight Engineer Program was an effort by the United States Air Force ( USAF ) to train American military personnel as payload specialist s for Department of Defense ( DoD ) missions on the Space Shuttle program . Background . The USAF and the National Reconnaissance Office ( NRO ) of the DoD participated in the development of the Space Shuttle from its official inception in 1969 . To save money , the shuttle was intended to serve as the United States ' national launch system for all civilian , military , and classified payloads . The DoD influenced key aspects of the shuttle ' s design such as the size of its cargo bay , and Congress reportedly told DoD that it would not pay for satellites not designed to fit into the bay . The USAF in the 1970s hoped to buy up to three shuttles and fly them with all - military crews . As with the earlier X - 20 Dyna - Soar and Manned Orbiting Laboratory , budget concerns ended the " Blue Shuttle " program , but the USAF gained the use of up to one third of all launches and the right to requisition the next available launch for high - priority payloads . It renovated an existing launch site at Vandenberg Air Force Base in California to send shuttles into polar orbit s and established the Manned Spaceflight Control Squadron . Its personnel monitored military shuttle flights from a secret floor of NASA ' s Mission Control Center in Houston , ahead of a future DoD mission control center in Colorado that would monitor an expected 12 to 14 flights each year . MSE . Many active - duty USAF and other American military personnel have served ( about 60 % of the total in 1985 ) , and continue to serve , as NASA astronauts . Although with the end of " Blue Shuttle " DoD no longer needed its own shuttle pilots and mission specialists , it still desired specially - trained military astronauts to handle classified payloads on the about 100 or more shuttle flights it expected to use . While NASA offered to train the DoD astronauts the military wanted to control their training , as DoD astronauts who went to NASA rarely returned . In 1979 , the first 13 Manned Spaceflight Engineers ( MSEs ) were selected , chosen from all services and based at Los Angeles Air Force Base : In 1982 , another 14 were selected , chosen only from the USAF : In 1985 , five more were selected : Secrecy . As a civilian agency , NASA typically freely provides details on all aspects of its operations . The DoD shuttle missions required different procedures to maintain secrecy of the classified payloads . The government viewed the flights and their payloads as secret as troop movements , asked media organizations to avoid reporting details , and threatened to investigate even " speculation " as potential leaks of classified information . The press nonetheless reported in great detail on likely military payloads using open source intelligence , such as the direction of the shuttle after liftoff . Unlike all other flights , NASA only began public countdowns a few minutes before launch , did not distribute press kits , and did not permit reporters to attend countdowns or listen to shuttle - to - ground communications . A secret USAF - NRO mission control center in Sunnyvale , California monitored flights alongside Houston mission control . NASA announced civilian shuttle missions ' schedules and flight routes in advance , hundreds of civilians attended most landings , and loudspeakers played radio transmissions . Only a few reporters and NASA employees , by contrast , attended the classified flights ' silent landings . Difficulties . The MSE program faced internal and external challenges . NASA , which early on had a " sour " relationship with the MSEs , was reluctant to assign them to its flights given their lack of NASA training and the need for spots for other payload specialists . Internal USAF debates on the usefulness of manned spaceflight to the DoD caused uncertainty for MSE personnel . New regulations in 1984 that strongly encouraged USAF personnel to move to another assignment after four years caused many early MSEs to transfer out of the program , with only nine active by late 1985 . End . The DoD stated in December 1984 that it planned to use about 20 % of the 70 shuttle flights NASA planned over the following five years , with almost all military - related launches moving to the shuttle from unmanned rockets . Before the loss of " Challenger " in January 1986 , however , ongoing launch delays caused DoD to express concern about overdependance on the shuttle . Despite Congressional and NASA opposition , in 1984 DoD began procuring a new unmanned rocket capable of launching shuttle - sized payloads into geosynchronous orbit . In 1985 it won approval to buy ten such rockets , which became the Titan IV . " Challenger " accelerated these plans but several NRO payloads only the shuttle could launch were grounded until it flew again , a dilemma NRO had feared as early as the mid - 1970s . With DoD ' s return to unmanned rockets and less need for dedicated military astronauts , the MSE program ended in 1988 with only two MSEs having flown into space . The Houston squadron was dissolved , construction of the Colorado center ended , and the Vandenberg launch site used for unmanned rockets . Only active duty - military NASA astronauts flew on subsequent missions with DoD payloads , the only exceptions being former Marine Story Musgrave and former DoD scientist Kathryn C . Thornton on STS - 33 . Shuttle missions with classified payloads . In 1993 a " high - ranking intelligence official " awarded all crewmembers of the classified shuttle flights with the National Intelligence Achievement Medal . The astronauts were permitted to wear the medals in public and discuss details of their flights that appeared on the medals ' citations .