Yesterday I had a fun flight at Tripoli Colorado in Hartsel that tied or maybe broke my personal record for highest-G boost at 120.1Gs.
TBH, there's not a lot to see in this video below, though I think one frame did catch the rocket. The sound is kind of fun.
View attachment 20230723_111032~2.mp4
Some fun facts from the Blue Raven data:
The nosecone is an Apogee 29mm plastic cone that I turned into a VK nosecone by molding some filled epoxy around it, in a silicone mold I made around 2011. The main chute compartment is a standard FG tube, and the aft end is built of some leftover tubes I had from way back when, joined by a coupler that also serves as the motor thrust ring. The av-bay shown in front is from 2 pre-production Blue Raven 29mm altimeters, and two 110 mAhr batteries. The batteries held up without a recharge for 2 flights yesterday. The av-bay, including some sealing bulkheads, harness attachment bulkheads, and charge holders that aren't shown, weighs 32 grams.
Unfortunately, the fins aren't nearly straight enough, which I saw as soon as I looked at the Blue Raven flight summary that was available on my phone as soon as I walked up to the rocket. Note the time to gyro overload and the number of ascent rolls:
After downloading the data, indeed the gyro got pegged at 2294 deg/seconds right away:
Despite that, it had reasonable results for the tilt angle, with the GPS flight angle and the tilt passing through 90 degrees at close to the same time:
The short-duration oscillations are the rocket coning. Each little bump represents another rotation. (Those fins were really not on very straight). The future tilt is what the Blue Raven calculates during the ascent for the predicted tilt 3 seconds into the future. This is useful for triggering airstarts that have some ignition delay.
Here's the altitude data, zoomed out. The Baro sensor has the expected under-prediction of altitude due to using the standard atmosphere model when it's hot out.
Zooming in on the first part of the flight you can see baro altitude artifacts from going above and below Mach 1:
The rocket took less than 1 second to get the first 1000 feet.
The GPS took a little while to figure out that someone hit it with a near-instant impulse to Mach 1.28. I was happy with the GPS performance, though. This is the updated Featherweight GPS tracker with the latest UBlox M10 receiver, which tracks an impressive number of satellites from all 4 constellations:
Here are the accelerations during the boost:
While I'll claim this as a 120G boost, mostly it's around 100 Gs. You can see the rocket bouncing within the rails of the 12' tower in the X and Y axes in the first 0.12 seconds.
I'll post more data in a minute, with a fresh allocation of images
TBH, there's not a lot to see in this video below, though I think one frame did catch the rocket. The sound is kind of fun.
View attachment 20230723_111032~2.mp4
Some fun facts from the Blue Raven data:
- The boost was 0.50 seconds long, but in the video it sounds longer because it broke Mach 1.0 at 0.38 seconds, so the sounds got stretched out.
- It broke Mach 1 just 200 feet above the pad.
- The coast time was 97.8% of the total time to apogee.
- It cleared the12 foot tower in 0.112 seconds, at 239 feet/second (163 mph)
The nosecone is an Apogee 29mm plastic cone that I turned into a VK nosecone by molding some filled epoxy around it, in a silicone mold I made around 2011. The main chute compartment is a standard FG tube, and the aft end is built of some leftover tubes I had from way back when, joined by a coupler that also serves as the motor thrust ring. The av-bay shown in front is from 2 pre-production Blue Raven 29mm altimeters, and two 110 mAhr batteries. The batteries held up without a recharge for 2 flights yesterday. The av-bay, including some sealing bulkheads, harness attachment bulkheads, and charge holders that aren't shown, weighs 32 grams.
Unfortunately, the fins aren't nearly straight enough, which I saw as soon as I looked at the Blue Raven flight summary that was available on my phone as soon as I walked up to the rocket. Note the time to gyro overload and the number of ascent rolls:
After downloading the data, indeed the gyro got pegged at 2294 deg/seconds right away:
Despite that, it had reasonable results for the tilt angle, with the GPS flight angle and the tilt passing through 90 degrees at close to the same time:
The short-duration oscillations are the rocket coning. Each little bump represents another rotation. (Those fins were really not on very straight). The future tilt is what the Blue Raven calculates during the ascent for the predicted tilt 3 seconds into the future. This is useful for triggering airstarts that have some ignition delay.
Here's the altitude data, zoomed out. The Baro sensor has the expected under-prediction of altitude due to using the standard atmosphere model when it's hot out.
Zooming in on the first part of the flight you can see baro altitude artifacts from going above and below Mach 1:
The rocket took less than 1 second to get the first 1000 feet.
The GPS took a little while to figure out that someone hit it with a near-instant impulse to Mach 1.28. I was happy with the GPS performance, though. This is the updated Featherweight GPS tracker with the latest UBlox M10 receiver, which tracks an impressive number of satellites from all 4 constellations:
Here are the accelerations during the boost:
While I'll claim this as a 120G boost, mostly it's around 100 Gs. You can see the rocket bouncing within the rails of the 12' tower in the X and Y axes in the first 0.12 seconds.
I'll post more data in a minute, with a fresh allocation of images
that's screaming.
