So last week was the HiFive to 5K launch at the Midland Rocketry “Midland Sky” weekend.  The weather was perfect and everything was set for a perfect launch. 

Cameras were mounted, motors installed and ready for the pad.

However!!!

When mounted on the pad and waiting for launch – igniter in but flight computers not armed (HiFive was on) the was an Unexpected Launch Event. The ULE happened when there was a mix up between the low power and high power pads and the launch controller was remotely armed and fired. Luckily the flight crew heard the Aerotech J415 (a 1280NS motor) come up to pressure and where able to dive for cover. No one was harmed but the rocket did launch without the recovery systems or cameras powered up.

An MRC investigation is underway to determine how the incident happened and as this was a ULE now video or still images were taken of the launch.

The rocket was very loud – well I was quite close and came back towards the ground ballistically due the RDAS flight computer not being armed.  The redundant motor ejection fired at 14sec and spilt the rocket into 2 at ~200m above the ground and the rocket came in hard to 8′ high corn/maize in the field behind the launch site.

The rocket took two days to find in the maze of maize but was recovered

As can be seen in the image below there was some significant damage to the launch vehicle but considering the lack of parachute deployment its certainly recoverable.

Finally…

On inspection of the electronics it was clear that all devices survived impact. The heavy separation caused the SD card holder to come apart and eject the SD card into the payload bay which amazingly was found next to the rocket.

Inspection of the data we can see that a peak altitude of 695.4m was achieved which is 2281.49′ Certainly short of the 4900+ simulations but this could be partly due to the rocket not being fully readied and not perfectly vertical at point of the ULE.

The HiFive also logged a peak acceleration of +2.8g at 0.73 seconds after ignition and the rocket was about 2g+ for 2.63 seconds (stated burn time of the motor is 3 seconds)

Data acquisition was lost at 223.65m or 733.75′ at a flight time of t+55.6 seconds.

What can we say about the HiFive

This device is one tough cookie. No we didn’t get it to 5000′ but hell the damn thing survived a near ballistic impact and is still fully functional.
It will fly again!