Summary

After we failed to recover Furiosity. I was offered to build and launch anothere capsule that we called “Revenge”. The sponsor had a really short deadline. I needed to make it happen in less than two weeks.

Simpler, the capsule contained 3 trackers, 2 cameras and one experiment. Jarrod Poston from Valley Christian High School gave us another experiment to fly and helped us during the launch.

The capsule was launched from Livermore, CA and reached an altitude of almost 103,000ft before landing 30 miles north. Though it didn’t follow the predicted route, the flight went by the book. We retrieved the capsule almost immediately.

While previous flights had taken weeks of preparation; Revenge was built, launched and recovered within 24 hours.

Actual flightpath

Maximum altitude reached

Hardware

Cameras	Canon PowerShot SD1200IS + 4Gb SD Card (photo script w/CHDK) GoPro2 + Battery BackPack + 32Gb SD Card (Class 10)
Power	Lithium Ion Polymer Battery & Energyzer Lithim ultimate batteries
Trackers	Byonics Micro-Trak RTG + Byonics GPS4 Spot Messenger Motorola  i296
Parachute	6ft Parachute

Flight Data

Launch Date	5/13/2012
Launch Point	37.235842,-122.416068 near Robertson Park, CA
Retrieval Date	5/13/2012
Landing Point	38.133379,-121.743536 near Rio Vista, CA
Balloon Lift	~48000g
Total weight	~4.0 lbs
Highest Altitude	102,959ft (31,382m)
Distance traveled	~32miles (52km)
Flight Duration	2h06min (Ascent took 1:27 hour)
Average ascent rate	1183ft/min
Average descent rate	2609ft/min
Landing speed	15 mph

The ascent rate is a bit too fast. It should be about 1000ft/min.
Two possible reasons for that:
-We put about 4800g of lift: 2000g (Capsule) + 1600g (balloon) + 1200g (free lift)
But it’s hard to gauge, we may have simply added too much helium.

-When we spread the balloon before inflating it, it seemed smaller than the previous 1600g we used. If so, a 1500g or 1200g would have required a lot less helium.

Sensor data

The only sensor data retrieved was sent by radio during the flight. (Time is in UTC)

The capsule was insulated with a 1inch Styrofoam wall. But due to the cameras access holes, the wall was thinner on many parts of the capsule. The temperatures recorded inside Revenge were colder than inside Furiosity.

Pictures

Both cameras were still running when we found the capsule.

Conclusions

• Attaching the parachute to the top of the capsule and not the sides made it a lot more stable.
• Attaching the parachute directly to the balloon is not the way to go. The weather balloon remains were found completely wrapped around the parachute lines.
• A simple 4400mA Lithium Ion Polymer Battery powered the GoPro video camera through the 2h flight without a hitch. The camera’s battery was still at 70% when found.
• Building a high altitude capsule and launching it within one weekend has successfully been demonstrated!