1. Critical Design Review Presentation
Submitted by:
Boy Scout Troop 143
382 N. Grimes
Giddings, Texas 78942

2. Agenda
Team Introduction
Vehicle Design
Questions

3. Team Introduction Members
- Preston Pruitt, Cody Alexander, Corbin Dillow, Skyler Newman, Taylor Blakney
Members are from the same Scout Troop and high school
Other activities include band, soccer, basketball & track

4. Rocket Flight Specifications & 2D Diagram
Length: 63 inches
Diameter: 6.17 inches
Span Diameter: inches
Mass (Empty): Oz
Mass with Engine: Oz

5. Stability Margin
With an additional 4 pounds of ballast in the nose, the stability margin reaches .51 calibers
Any and all construction measures to lighten the airframe will be considered

6. Thrust to Weight Motor Selection in Flight Simulation
Motor Selected – Aerotech K1050W
Calculations:
- Motor impulse in Newtons / 4.45 = avg. thrust in pounds
1050 / 4.45 =
- Thrust (lbs) / total vehicle weight (lbs) = Thrust to Weight ratio
/ 24.4 = Thrust Ratio
- Generally accepted minimum 5:1
Rail Exit Velocity : fps

7. Parachute Sizes & Descent Rates
Recovery system data
Drogue
Size – 30”
Altitude at deployment – 2862 ft
Time of deployment – seconds after launch
Velocity at deployment fps
Predicted descent rate fps
Main
Size – 84”
Altitude at deployment –400 ft
Time of deployment – 45 seconds after launch
Velocity at deployment - 74 fps
Predicted descent rate fps

8. Test Plans & Procedures
Ground test (vacuum jar) of complete avionics sled (4 altimeters).
Launch prep and sequence will be reviewed and finalized during ground tests.
Verification of reliability in both data collection and recovery deployment during ground tests.
Ejection charge ground tests will be performed.
Our launch and safety procedures will follow NAR guidelines.

9. Scale Model Flight Test
Rocket design performed well
Powerful, straight flights in windy conditions
Successful recovery deployment
Initial altitude readings: 1,100 and 1,800 feet

10. Scale Model Flight Test
Electronics Issues
Second flight data stream incomplete due to poorly charged battery
Data examination revealed severe pressure spike at ejection
Additional experience needed with data retrieval and manipulation

11. Dual Deployment Avionics Test
Our final ground test plans will merge the pre-flight procedures from both brands of altimeters.
Simple “vacuum jar” tests will be performed.
Both simple circuit tests (LED) and charge tests will be performed.

12. Ejection Charge Amount Test
Ejection charge testing will be conducted.
Current estimates for black powder charge
For a 6” airframe, 5.3 psi is desirable (150 lbs force)
C * D * D * L = grams of BP
.002 * 6*6*12 = .86 g Main
.002 * 6*6*8 = .58 g Drogue

13. Payload Integration Feasibility
The payload is essentially a double-redundant dual deployment system employing high-rate altitude and G-force data recording
Integration appears to be no more complex than a standard dual-deploy avionics configuration

14. Questions?