Alcor (rocket engine)

Alcor (also known as Zebra or 30-KS-8000) was a solid rocket engine, originally developed by Aerojet for the US Air Force as the third stage of the Athena test vehicle.

[1][2][3] Its main appeal was a high mass fraction due to the Aerowrap chamber fabrication process.

However, production issues with joint sections limited its use.

[1] Initially produced with polyurethane propellant, it transitioned to polybutadiene, leading to the Alcor 1A (23KS-11000) variant.

[1][4][5] This variant featured improved nozzle, chamber insulation, and expansion ratio, increasing the mass fraction from 0.886 to 0.906.

Alcor is the third stage of the Athena sounding rocket
Alcor 1A was used on the Athena H sounding rocket