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The Hermes 2 vehicle was 138.2 inches long and weighed 167.4 lbs at liftoff. For the second year in a row the FAR ignition system experienced difficulties on the first launch attempt. A quick recycle of the count and a hot-swap to FAR's wireless system yielded positive results and the motor lit successfully. A timeline of flight events is presented below. The onboard video is considered the timing master for all events.
| Event | Time [s] | Altitude [m] | Velocity [m/s] | Notes | ||||
|---|---|---|---|---|---|---|---|---|
| Ignition | -0.80 | 0 | 0 | Audio transient used. Flames not visible for another .14s | ||||
| Liftoff | 00:.00 | 0m0 | 0 m/s | Absolute time reference at first vehicle motion | ||||
| Tower Clear | 00.33 | 6 | 47 | |||||
| Pitch Event | ||||||||
| Start of Constant Roll Acceleration | Continued until end of powered flight | |||||||
| Start of Constant Roll Increase | 03.37 | 749 | 516 |
| ||||
| Pitch Event | 03.69 | 886 | 569 | |||||
| High-G Event | 06.07 | 2849 | 918 | This event likely saturated the on board accelerator for .02s at a reading of 32 G | ||||
| Vehicle Disintegration | 06.35 | 3011 | 920 | Body rates jump from <10 degrees/s to >300 degrees/s. Tilt angle exceeds 45 degrees (previously 16 degrees) | ||||
| Piston Actuates | 11.67 | 3679 | Unknown | Velocity measurements likely inaccurate | ||||
| Mission Package Impact | 70.40 | 0 | 70 | Interpolated. Last data point logged at 34m altitude and -28 m/s, which is almost certainly inaccurate. Previous recorded value used. | ||||
| Booster Impact | 108.60 | 0 | 46.5 | Booster impact velocity estimated from kinematic model with estimated terminal velocity. |
The exact cause of the anomaly is unlikely to be conclusively determined, but we have several open fault trees which provide a path forward to resolve high-risk items prior to flying again.
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