TheNewGuy
Well-Known Member
- Joined
- Apr 24, 2017
- Messages
- 48
- Reaction score
- 1
Hello everyone,
I am an Electrical Engineering student who started getting into rocketry last year, and I am absolutely addicted. I've been trying to learn as much as I can from wherever I can, and I am really enjoying it.
I built my first rocket a couple months ago, which is an LOC Hi-Tech I purchased on Apogee Components. I got Level-1 certified by flying it on an Aerotech H123W-14, and I can't wait to fly my rocket again. I have a lot of questions though, and I was hoping you guys could help answer them for me. I'm confused on the motor selection process:
1.) Simulations
Apogee Components has on their website the RockSim file for the Hi-Tech, and when I run simulations on it, I can't seem to get the same numbers for altitude that they list on their website. For example:
According to Apogee Components they say that it should reach a maximum altitude of 3,266 feet (Link here), but when I run RockSim it gives me 1,100 feet. I've tried different motors, and I always get drastically lower numbers in the simulations than what's listed. Is there something I'm doing wrong?
2.) Choosing Delay
After running the simulation, the software suggests an "optimal delay" to use with the motor. On the Aerotech H123W and various other motors, it suggests a delay of 1 second. Does that mean, using the delay drilling tool, I keep drilling until I'm down to 1 second? Also, does the delay burn immediately after the rocket is launched or after the propellant grain finishes burning?
3.) Level-2 Flight on the Hi-Tech
On the on Apogee's website, they say that for a level-2 flight you should use a slow burning J motor (specifically the J90). If you want to use a quick burning J, they suggest laying fiberglass the body and fins. I notice that the J90 isn't sold anymore, are there alternatives to the J90 or should I just go ahead and fiberglass the rocket when I want to do Level-2?
4.) Endburn-Style Forward Closure
For the Aerotech I49 and I59, they require a different forward closure than regular reloads. From what I understand, this forward closure doesn't have the small hole at the top that is usually where the black powder gets ignited. How does the black powder get ignited for these motors? Electronics only?
Thank you in advance for any help, and sorry for the barrage of questions in my first post.
Regards,
TNG
I am an Electrical Engineering student who started getting into rocketry last year, and I am absolutely addicted. I've been trying to learn as much as I can from wherever I can, and I am really enjoying it.
I built my first rocket a couple months ago, which is an LOC Hi-Tech I purchased on Apogee Components. I got Level-1 certified by flying it on an Aerotech H123W-14, and I can't wait to fly my rocket again. I have a lot of questions though, and I was hoping you guys could help answer them for me. I'm confused on the motor selection process:
1.) Simulations
Apogee Components has on their website the RockSim file for the Hi-Tech, and when I run simulations on it, I can't seem to get the same numbers for altitude that they list on their website. For example:
According to Apogee Components they say that it should reach a maximum altitude of 3,266 feet (Link here), but when I run RockSim it gives me 1,100 feet. I've tried different motors, and I always get drastically lower numbers in the simulations than what's listed. Is there something I'm doing wrong?
2.) Choosing Delay
After running the simulation, the software suggests an "optimal delay" to use with the motor. On the Aerotech H123W and various other motors, it suggests a delay of 1 second. Does that mean, using the delay drilling tool, I keep drilling until I'm down to 1 second? Also, does the delay burn immediately after the rocket is launched or after the propellant grain finishes burning?
3.) Level-2 Flight on the Hi-Tech
On the on Apogee's website, they say that for a level-2 flight you should use a slow burning J motor (specifically the J90). If you want to use a quick burning J, they suggest laying fiberglass the body and fins. I notice that the J90 isn't sold anymore, are there alternatives to the J90 or should I just go ahead and fiberglass the rocket when I want to do Level-2?
4.) Endburn-Style Forward Closure
For the Aerotech I49 and I59, they require a different forward closure than regular reloads. From what I understand, this forward closure doesn't have the small hole at the top that is usually where the black powder gets ignited. How does the black powder get ignited for these motors? Electronics only?
Thank you in advance for any help, and sorry for the barrage of questions in my first post.
Regards,
TNG