High-Power Rocketry Certification
L1 & L2 Certification Rocket
OpenRocket Model - Kamino V1.1 airframe for L1 & L2 certification flights
Flight Parameters
Mass without motors
1603 g
Mass with motors
2410 g
Length & Diameter
112 cm | 8 cm
Stability margin
1.45 cal (10.4%) at M = 0.3
CG & CP
73.4 cm | 85 cm (at M = 0.3)
Predicted apogee
1435 m
Max velocity
158 m/s (Mach 0.468)
Max acceleration
126 m/s²
Mission
Design and launch a rocket that can safely carry an I-class L1 certification flight and a J-class L2 certification flight in one single rocket, within a single day, with adequate stability margin for both flights.
Design Approach
Flight tests revealed a stability margin of 1.45 calibers (10.4%) at a center of gravity of 73.4 cm and center of pressure of 85 cm from the nose for Mach 0.3. This margin should have been maintained through both the I-motor L1 flight and the J-motor L2 flight because both flights share the same airframe and fin design.
Certification Path
Step 01 — Level 1
I Motor
The first certification flight will use the I motor and will act as the L1 certification flight and the test of the simulation flight profile.
Step 02 — Level 2
J Motor
My plan is to take the L2 written test right after passing the L1 flight test and then to fly the same airframe using the J motor for L2 certification.
OpenRocket Simulation - Altitude, velocity, and acceleration vs. time for L1 & L2 flights
Manufacturing
However, from the outset, the airframe had been dimensioned and designed to be able to withstand the greater impulses as well as masses that result from the use of the J engine, despite the fact that the initial flight uses an I engine for L1.
Reflection
"Because the airframe was designed to carry out both the certification flights, the margin of stability and structural design had to be made taking into account the heavier weight of J-motor, rather than designing L1 and L2 separately."
Skills Learned