When the Space Shuttle Discovery (STS-114) returns to flight, it will have a special escort, but the pair of NASA WB-57 chase jets won't just be along for the ride. 

Thanks to an engineering team that includes NASA's Marshall Space Flight Center in Huntsville, Ala. and key industry partners, these high-flying chase planes will provide NASA with extra "eyes in the sky" to watch Discovery's flight and help safeguard its crew.

Approximately 4” Diameter