solid rockets on it, is hard to rationalize. In retrospect it is clear this was a disaster waiting to On 28 January, 1986 the Challenger took off with a teacher on board and exploded 73 seconds later. The immediate cause of the explosion was a burn through of one of the O-rings on one of the solid rocket boosters causing the shuttle Challenger to be ripped apart at altitude. In the investigation that followed a number of contributing factors were identified. First, NASA managers under pressure to show the STS was reliable had authorized a launch even though the temperature criteria were outside of the known operational range of the STS. In a sense the operational mindset had overtaken them. They overruled the engineers who warned of possible danger. Second, NASA engineers had known for some time that there were problems with gas blowby through the O-rings. However, the NASa system ignored these signs and did not calculate the consequences of a blowby Third the nasa communication system by this time was so poor that senior managers did not know of these potential issues and the nasa administrator for the first time ever did not go to the Cape for the launch. Thus the r&d agency which had done Apollo in a few short years was reduced to an operational agency which could not even do this job well The Challenger disaster struck the national psyche like Sputnik. It was made all the more visible by the fact that so many school children were watching. It plunged the space program and space policy into a huge crisis. Unhappily, there were several other launch failures that occurred at about the same time. These included in April 1986, a Titan 34D at Vandenberg and in May,a NASA Delta rocket that was launched into a thunderstorm Could NASa do nothing right! The result was that all launch activity was grounded for several years while the technical issues were fixed while the space policy was adjusted. The consequences of putting all the nation's eggs in only one major basket now meant that the US had no reliable means to get to space. The StS was grounded for 31 months and in that time space policy was transformed and the Air Force commercial, international and NASA communities repositioned themselves. Since no launches were available on US rockets, many commercial satellite contractors turned to Arianespace. The US market shares of commercial launch plummeted and Ariane took significantly more than 50% of the free world market. In a sense, the space policy of not allowing the French to use American rockets which pushed them to develop their own and putting all the Us eggs in the Shuttle basket led directly to Ariane capturing most of the commercial market. Fortunately, many satellites had been designed to fly on the Shuttle and on the Ariane. After much debate in the space policy community, it was decided that the Shuttle would only be used for national security missions and for scientific missions where human presence was essential. All commercial communication satellites were pushed off the Shuttle and told to find other rides. This caused chaos in the commercial community and pushed them into the arms of Ariane. Of course this policy of using the Shuttle only when essential is a testament to the fact that it will never be an economic proposition. The dod decided that it wanted to move away from the Shuttle and return to a mixed fleet of ELV's for assured access to space. Thus it cancelled the development of SlC6 at Vandenberg and restarted the Delta, Centaur and Titan lines. It agreed to buy 20 Deltas, 11 Centaurs and 24 Titans as a deliberate attempt by government policy to kickstart a dying industry It also agreed to provide range support for all launches at the etR and WTR for only direct costs Thus the dod deliberately agreed to subsidize the commercial space industrsolid rockets on it, is hard to rationalize. In retrospect it is clear this was a disaster waiting to happen. On 28 January, 1986 the Challenger took off with a teacher on board and exploded 73 seconds later. The immediate cause of the explosion was a burn through of one of the O-rings on one of the solid rocket boosters causing the shuttle Challenger to be ripped apart at altitude. In the investigation that followed a number of contributing factors were identified. First, NASA managers under pressure to show the STS was reliable had authorized a launch even though the temperature criteria were outside of the known operational range of the STS. In a sense the operational mindset had overtaken them. They overruled the engineers who warned of possible danger. Second, NASA engineers had known for some time that there were problems with gas blowby through the O-rings. However, the NASA system ignored these signs and did not calculate the consequences of a blowby. Third, the NASA communication system by this time was so poor that senior managers did not know of these potential issues and the NASA administrator for the first time ever did not go to the Cape for the launch. Thus the R&D agency which had done Apollo in a few short years was reduced to an operational agency which could not even do this job well. The Challenger disaster struck the national psyche like Sputnik. It was made all the more visible by the fact that so many school children were watching. It plunged the space program and space policy into a huge crisis. Unhappily, there were several other launch failures that occurred at about the same time. These included in April 1986, a Titan 34D at Vandenberg and in May, a NASA Delta rocket that was launched into a thunderstorm. Could NASA do nothing right! The result was that all launch activity was grounded for several years while the technical issues were fixed & while the space policy was adjusted. The consequences of putting all the nation’s eggs in only one major basket now meant that the US had no reliable means to get to space. The STS was grounded for 31 months and in that time space policy was transformed and the Air Force, commercial, international and NASA communities repositioned themselves. Since no launches were available on US rockets, many commercial satellite contractors turned to Arianespace. The US market shares of commercial launch plummeted and Ariane took significantly more than 50% of the free world market. In a sense, the space policy of not allowing the French to use American rockets which pushed them to develop their own and putting all the US eggs in the Shuttle basket led directly to Ariane capturing most of the commercial market. Fortunately, many satellites had been designed to fly on the Shuttle and on the Ariane. After much debate in the space policy community, it was decided that the Shuttle would only be used for national security missions and for scientific missions where human presence was essential. All commercial communication satellites were pushed off the Shuttle and told to find other rides. This caused chaos in the commercial community and pushed them into the arms of Ariane. Of course this policy of using the Shuttle only when essential is a testament to the fact that it will never be an economic proposition. The DOD decided that it wanted to move away from the Shuttle and return to a mixed fleet of ELV’s for assured access to space. Thus it cancelled the development of SLC6 at Vandenberg and restarted the Delta, Centaur and Titan lines. It agreed to buy 20 Deltas, 11 Centaurs and 24 Titans as a deliberate attempt by government policy to kickstart a dying industry. It also agreed to provide range support for all launches at the ETR and WTR for only direct costs. Thus the DoD deliberately agreed to subsidize the commercial space industry. 3