About: Solid Rocket Motor Upgrade

The Solid Rocket Motor Upgrade (SRMU) was a solid rocket motor that was used as a booster on the Titan IVB launch vehicle. Developed by Hercules (later ATK), it was intended to be a high-performance, low-cost upgrade to the UA1207 boosters previously used on Titan IV. Wound from carbon-fibre-reinforced polymer and burning a hydroxyl-terminated polybutadiene-bound ammonium perchlorate composite propellant, it was an ambitious upgrade building on Hercules' experience developing a filament-wound case for the Space Shuttle SRB. Originally intended to fly in 1990, it instead first flew in 1997 due to a protracted development and lack of demand. The SRMU performed successfully on all of its flights.