This flight was originally scheduled for June of 2018. It is now scheduled for March 2019. In the interim the team has moved the expected launch site to Black Rock.
Goals
Team:
1. Fly to 80,000 ft
2. Recover to reflyable condition
3. Collect data: Nose cone heating throughout flight, load data from parachutes, visual data of parachutes, altitude, acceleration, vibration (NC and lower electronics)Recovery:
Add desired landing velocity, landing radius, other expectations
Structures:
All structures survive flight, nothing breaks, materials survive temperature changes
Avionics:
Measure altitude & acceleration and actuate necessary flight events
Payload:
Collect data on nose cone heating throughout flight
Propulsion:
Fly to 80,000 ft, motor performs nominally (no CATO, thrust curve within 5%)
Flight Data Files
Pyxida:
StratoLogger:
TeleMetrum:
Weather
https://weatherspark.com/y/3193/Average-Weather-in-Truth-or-Consequences-New-Mexico-United-States-Year-Round
Parameters | Nominal Value |
Launch Tower Ht. | |
Launch Site Altitude | 1406m |
Landing Site Altitude | |
Temperature | 68-95 |
Baro Pressure | 29.68 Hg |
Latitude | 32.9904 |
Longitude | 106.9750 |
Time | Windspeed |
7AM | NNW Wind:3.728 mph |
4PM | N Wind:6.836 mph |
CAD
Video
Simulator Files:
12-17-2017
I've spent a few hours digging through RASAero, Open Rocket, BurnSim, the Mass Budget, and hitting all of the above with healthy doses of common sense. Andrew gave me a few good ideas on where to start sanity checking our numbers. I know these values still sound on the high side, but I'm inclined to believe them pending flaws inthesimfiles. I would be very happy to hit 80% of these values though, knowing how these kinds of flights go.
In case anyone was curious,therocksimfilethepreviousrasaeronumberswerebasedoffofstillwas usinganoffaxispistonand was almost 2 feet longer than the current design. This has led to some stability problems with the current design. At Burnout we hit a stability margin of 1.11. As this happens at Mach 3.35 I think we should increase the fin size to compensate.
These files are now correct to the design, as I understand it.
Motor file: 70kNs Rev 6
Composite Fin Can, OD of fin collar 6.25 in, 1/4 thick fins. .75 in edge chamfer .05 in rounding on edges.
Surface Finish: Rough Camouflage Pain
Rocket Length 11 feet 8 inches
GLOW is 158 lbs according to Mass Budget
Aft Closure include Boat Tail to 5.6 in aft diameter
Here are the relevant quantities.
GLOW: 158 lbs, +/- 14 lbs
Burnout Altitude: 12,200 ft AGL
Burnout Velocity 3,700 ft/s (Mach 3.35)
Maximum Altitude: 125,600 ft +/- 23,100 ft (from mass deltas)
These values came from some hand runsofRasAero
The next set of values came from OpenRocket on a dataset of 500 runs through Cassandra (Thanks Josh!). The raw values are quite different than the Open Rocket values, but with a healthy fudge factor (screwing with finishes and fin thicknesses) to get supersonic cd's to matchthoseofRasAero, the numbers were similar.Secondsemesterwe should improve Cassandra's aerodynamics. Anyways, Cassandra gives the following
GLOW = 158 lbs
Apogee 131,529 +/- 6,443 ft
Median Apogee = 133,142 (An average flight is pretty close to the average of the flights, which is good)
3-Sigma Altitude = 138,870 ft
Landing Zone = 4.3 miles east of base camp +/- 1.4 miles
Attached are the sim results that I ran on RASAero. Included are the files that I ran the sim with. The total mass and CG were taken from my (Maddie's) latest local OpenRocket file (attached here). The loaded mass is a little different that the latest mass budget suggests, but I have widened the tolerance from 7% to 10% to account for this. -Maddie
