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This is the flight motor for Hermes Flight 1. The motor is almost identical to the second 4G 152mm OW static, but uses 8.5" long grains to increase propellant mass slightly. It was decided that this was reasonable deviation from the tested motor as it was only 3% more propellant. Another modification was the addition of a thrust ring to the nozzle carrier, but this was also a safe move change as it did not modify how the motor functioned internally. The burn was perfect and propelled Hermes 1 to around 32,000', RT's highest flight yet and our first use of custom propellant in a rocket.
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