- Joined
- Sep 16, 2010
- Messages
- 77
- Reaction score
- 7
To all:
I designed and built my own twin engine cluster rocket using rocksim. I originally wanted to fly it with Estes E9's for the "low and slow" effect. I then realized I was pushing my luck weight wise and asked for advice. See https://www.rocketryforum.com/showthread.php?25756-Maximum-safe-lift-off-weight-velocity-using-E9-s
Fast forward to now when I can fly it and the results have been odd. I have flown it four times. All four have had similar flight profiles. The flight starts off vertical and then goes horizontal and results in crashes or near crashes
1) Twin Aerotech D15-4T's. Up...horizontal..down...parachute deploys just above ground..broken fin
2) Twin Estes E9-4 Up higher...horizontal..down...parachute deploys just above ground
3) Twin Estes E12-4 Up even higher to about 300 feet...horizontal..down...parachute deploys at 200'
4) Twin Aerotech E18-4W Results similar to 3 BUT I almost take out a dog on the landing to the horizontal flight of about 400 yards.
The other odd thing is I used the Estes Sonic igniters on the Aerotech clusters. Both times the igniters went along for the ride!
Here are the launch photos of the E18's. Note the awesome flame and launch wire traveling upward.
I would like to know why my rocket likes to fly this way. I can not reproduce a near horizontal flight in Rocksim. I have accurately weighed the rocket when loaded and inputted that info to rocksim and it has around 1.5 calibers of stability.
I really like my launch field but want to protect innocent civilians and dogs. You can see my rocket almost landing on the dog at the 0:58 second mark.
[video=youtube_share;JtXm10yCDGI]https://youtu.be/JtXm10yCDGI[/video]
thanks
Jim
I designed and built my own twin engine cluster rocket using rocksim. I originally wanted to fly it with Estes E9's for the "low and slow" effect. I then realized I was pushing my luck weight wise and asked for advice. See https://www.rocketryforum.com/showthread.php?25756-Maximum-safe-lift-off-weight-velocity-using-E9-s
Fast forward to now when I can fly it and the results have been odd. I have flown it four times. All four have had similar flight profiles. The flight starts off vertical and then goes horizontal and results in crashes or near crashes
1) Twin Aerotech D15-4T's. Up...horizontal..down...parachute deploys just above ground..broken fin
2) Twin Estes E9-4 Up higher...horizontal..down...parachute deploys just above ground
3) Twin Estes E12-4 Up even higher to about 300 feet...horizontal..down...parachute deploys at 200'
4) Twin Aerotech E18-4W Results similar to 3 BUT I almost take out a dog on the landing to the horizontal flight of about 400 yards.
The other odd thing is I used the Estes Sonic igniters on the Aerotech clusters. Both times the igniters went along for the ride!
Here are the launch photos of the E18's. Note the awesome flame and launch wire traveling upward.
I would like to know why my rocket likes to fly this way. I can not reproduce a near horizontal flight in Rocksim. I have accurately weighed the rocket when loaded and inputted that info to rocksim and it has around 1.5 calibers of stability.
I really like my launch field but want to protect innocent civilians and dogs. You can see my rocket almost landing on the dog at the 0:58 second mark.
[video=youtube_share;JtXm10yCDGI]https://youtu.be/JtXm10yCDGI[/video]
thanks
Jim