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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 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.
Statistic | Value |
|---|---|
| Propellant Weight | Sam add this |
| Impulse | 32900 Ns |
| Max Pressure | Unknown |
| Classification | O-4300 |
| Delivered ISP | Sam add this |
| Grains | OW-152 #25-28 |
Media
Data
To determine data about the motor, the acceleration graph from the telemetrum was exported and combined with velocity data, estimated rocket mass at the time of each datapoint, and the CD from Ras Aero to calculate the thrust of the motor at each sample. The result matched the expected value based on the previous test, so this method seems to work well.
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