In early 1995, the US Air Force made a secret trip to Poitiers’ small airport to collect batteries for the Centaur launcher.
In the early 1980s, Saft worked on a lithium-thionyl chloride battery for Boeing’s Inertial Upper Stage (IUS) vehicle, built for the US Air Force. The IUS vehicle was carried into space either by a rocket or the Space Shuttle and would then transport satellites from low Earth orbit into geostationary orbit. However, budget cuts ended the initiative in February 1988.
At that time, General Dynamics Space Systems (GDSS) issued a call for tenders to improve the launcher and Centaur stage of the Titan IV rocket, which was supposed to launch military payloads for the US Air Force. Thanks to technological advances achieved through the IUS program as well as earlier space projects, Saft won the contract.
This project involved developing a 30-volt, 250-ampere hour lithium-thionyl chloride battery weighing a maximum of 33.5kg, to replace the 70kg silver oxide-zinc battery.
This amounted to significant weight savings for the US Air Force.
Work began on August 16, 1988, but problems quickly piled up for GDSS: there were technical issues, cost overruns and missed deadlines. Meanwhile, the global political environment was changing. The fall of the Berlin Wall and the subsequent economic crisis hit military budgets hard.
Eventually, in February 1992, Saft received an order to manufacture 10 batteries. With one battery left to deliver, the USAF wanted to jettison the program as a cost-cutting measure. Work ceased with the project at an impasse.
One year later, GDSS and Martin Marietta Space Systems persuaded the US Air Force to fund a demonstration of the batteries in flight. That led to a July 1994 order for Saft to produce four batteries for delivery in early 1995.
With little time, Saft worked hard to fill the order and a US Air Force plane made an incognito trip to Poitiers to collect the batteries. Flight 23 of the Titan IV-Centaur launcher ultimately took off successfully from the Cape Canaveral base in Florida on May 14, 1995.