UDMH is stable and can be kept loaded in rocket fuel systems for long periods, which makes it appealing for use in many liquid rocket engines, despite its cost. In some applications, such as the OMS in the Space Shuttle or maneuvering engines, monomethylhydrazine is used instead due to its slightly higher specific impulse. In some kerosene-fueled rockets, UDMH functions as a starter fuel to start combustion and warm the rocket engine prior to switching to kerosene.
UDMH is stable and can be kept loaded in rocket fuel systems for long periods which makes it appealing for use in many liquid rocket engines despite its cost In some applications such as the OMS in the Space Shuttle or maneuvering engines monomethylhydrazine is used instead due to its slightly higher specific impulse In some kerosene-fueled rockets UDMH functions as a starter fuel to start combustion and warm the rocket engine prior to switching to kerosene