ebruce1361
The man with the plan. And some duct tape.
Keep It Simple, Stupid. That's what they tell me, but I take a certain pleasure in complicated challenges.
Back in April last year, I had the crazy idea to jump on the bandwagon and buy one of the Apollo 11 commemorative Saturn V kits and modify it fly on a cluster of five D12 motors. It took my family and I several months to assemble this behemoth, but we did it and almost had it ready in time for the 50th anniversary. Unfortunately, schedule changes happened over and over and we didn't get to fly it until December 21st.
Now, the way I designed the cluster arrangement was very specific. The center tube was to be loaded with a D12-5 as a backup ejection, then the two outboard tubes that ran all the way through to the parachute bay were to be loaded with D12-3s for the primary ejections, and then the two shorter tubes (which had been sealed off with JB Weld bulkheads) were to have D12-0s to only offer additional thrust.
I ran this thing through Openrocket at least fifty times with minor variations to the motor arrangement to get the ideal delay time, and I was satisfied with the results. I knew I wouldn't break any altitude records with it, (it weighed 998 grams loaded), but it was stable. I spent the second half of the summer just working on the paint and details. I know a lot of people use the ten-foot rule when it comes to rockets intended to fly, but I wanted to put in the work. I wanted this to look just as good from a foot away as it would atop a column of smoke from 30 feet away.
When we went to the club meet, we started out flying our smaller stuff because it was pretty gusty, and to use up some old motors. Well, we had a few far drifters making recovery take longer than expected, so I was startled when the LCO announced they were wanting to wrap up for the day and wanted the last couple of racks set up.
Here's where I messed up. Honestly I think my design was good, albeit complex, but a momentary lapse in attention to detail made for a critical error. I inserted the D12-5 where it belonged, but I transposed the D12-0s and D12-3s by mistake. I didn't notice the error until after recovery.
Ignition of all five motors and liftoff was PERFECT! It was so beautiful and offered a healthy roar for the first two seconds or so.
Then things went weird. The nose section separated much earlier than it should have with the rocket still traveling at nearly full speed.
This of course tangled up the parachutes, and instead of the booster coming down under three chutes and the nose under one, the booster came under only two while the nose came in ballistic and buried itself eight inches in the soil. (Luckily the ground was soft and the only damage is the nose was dirty and the escape tower broke off the command module)
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Back in April last year, I had the crazy idea to jump on the bandwagon and buy one of the Apollo 11 commemorative Saturn V kits and modify it fly on a cluster of five D12 motors. It took my family and I several months to assemble this behemoth, but we did it and almost had it ready in time for the 50th anniversary. Unfortunately, schedule changes happened over and over and we didn't get to fly it until December 21st.
Now, the way I designed the cluster arrangement was very specific. The center tube was to be loaded with a D12-5 as a backup ejection, then the two outboard tubes that ran all the way through to the parachute bay were to be loaded with D12-3s for the primary ejections, and then the two shorter tubes (which had been sealed off with JB Weld bulkheads) were to have D12-0s to only offer additional thrust.
I ran this thing through Openrocket at least fifty times with minor variations to the motor arrangement to get the ideal delay time, and I was satisfied with the results. I knew I wouldn't break any altitude records with it, (it weighed 998 grams loaded), but it was stable. I spent the second half of the summer just working on the paint and details. I know a lot of people use the ten-foot rule when it comes to rockets intended to fly, but I wanted to put in the work. I wanted this to look just as good from a foot away as it would atop a column of smoke from 30 feet away.
When we went to the club meet, we started out flying our smaller stuff because it was pretty gusty, and to use up some old motors. Well, we had a few far drifters making recovery take longer than expected, so I was startled when the LCO announced they were wanting to wrap up for the day and wanted the last couple of racks set up.
Here's where I messed up. Honestly I think my design was good, albeit complex, but a momentary lapse in attention to detail made for a critical error. I inserted the D12-5 where it belonged, but I transposed the D12-0s and D12-3s by mistake. I didn't notice the error until after recovery.
Ignition of all five motors and liftoff was PERFECT! It was so beautiful and offered a healthy roar for the first two seconds or so.
Then things went weird. The nose section separated much earlier than it should have with the rocket still traveling at nearly full speed.
This of course tangled up the parachutes, and instead of the booster coming down under three chutes and the nose under one, the booster came under only two while the nose came in ballistic and buried itself eight inches in the soil. (Luckily the ground was soft and the only damage is the nose was dirty and the escape tower broke off the command module)
{STORY CONTINUES IN COMMENTS IN ORDER TO LOAD ADDITIONAL PICTURES}
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