High Power Rocketry: L2 Certification Flight

Officially level 2 certified!

rocket launching into the blue sky, with fire and smoke below
textbook flight

Fulfilling a 2020 goal

I really started getting into rocketry last fall, less than a year ago, and I had set some goals for 2020 when the year began. My goals included getting level 1 and level 2 certifications in high power rocketry (HPR) through the National Association of Rocketry (NAR).

I think 2020 threw some curveballs at just about everybody, myself included – but after a few false starts and delays, I was able to launch my first high power rocket in central Washington on a beautiful day in June, and as I wrote about previously, I got my L1 cert.

I deliberately chose and constructed a rocket that could be used for both L1 and L2 certification (i.e. it is capable of launching on a more powerful motor), and I built it to be dual deploy capable. I also had plenty of time to study for the written exam, which is required after the L1 certification but prior to the L2 flight. Timing is everything.

Because of this, I was able to do everything in a single day – L1 flight, L2 written exam (which I passed, of course), and L2 flight. I had more than six months to prepare for this day, so it’s not particularly impressive!

white rocket with orange and yellow parachutes lying on ground in green field
a safe landing

L1 vs. L2 flights

On the L1 flight – the maiden voyage – I didn’t want to take any unnecessary risks and decided to keep it as simple as possible, so I didn’t attempt using any electronics or dual deploy. The rocket separated through a simple motor ejection charge.

But for the L2 flight, I wanted to try the flight computer and dual deploy. I was a little nervous because while I checked and rechecked everything in advance, this was still the first actual attempt and there were a lot of firsts: first time using any flight computer or black powder charges, first time arming the electronics on the launch pad, first time using the ground station to communicate via radio with the rocket (using a laptop with the appropriate software and a connected Yagi antenna), etc.

Everything went smoothly, from the launch (see first photo above) to deployment of the drogue parachute at apogee and the main parachute closer to the ground. I recovered the rocket without any damage.

white rocket with text "improbable ventures" lying on ground in green field
mildly improbable

L2 flight data breakdown

What’s particularly cool is the flight computer not only fires multiple pyro charges (and therefore controls the rocket’s separation and deployment of two parachutes), but it also contains an altimeter and other sensors that record the rocket’s maximum height and its descent speed.

For my L2 flight, the rocket reached 3,506 ft, with a maximum speed of 599 ft/sec (Mach 0.5). In other words, the rocket’s max speed was about one-half the speed of sound.

The descent rate under the drogue parachute was 39 ft/sec, and under the main parachute it was 27 ft/sec. The HyperLOC 835 is a fairly lightweight cardboard rocket with a gross liftoff weight (that is, a weight including the motor, parachutes, and everything else inside) of only about 6 lbs, and this descent rate was more than sufficient for a safe landing.

All in all, this was a fantastic experience. A four hour drive each way made this a very long day, but it was absolutely worth making the trip. Inevitably, I also learned a tremendous amount – for example, how to set up a large rocket on the pad and launch rail, how to use the flight computer and ground station software, etc. I also learned what types of things that I could do better next time. Overall, I’m even more excited about future launches – trying out new techniques, flying on even more powerful motors, and capturing data with the flight computer to beat my own previous records!

2 thoughts on “High Power Rocketry: L2 Certification Flight

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