Exhaust holes: E12-0 vs E12-0

[shockie]

This video shows 2 E12-0 with exhaust hole vents versus 1 E16-6 with exhaust hole venting.

I want you to notice how the E12 exhaust vent streams are of a much shorter duration and intensity versus the longer duration and more explosive E12-6 exhaust vent stream is.
Also notice the sparks flying from the 2 E12-0 ie flaming particles.....@ 2:21.

compare 2:21 to about 2:45

 

[SharkWhisperer]

This video shows 2 E12-0 with exhaust hole vents versus 1 E16-6 with exhaust hole venting.

I want you to notice how the E12 exhaust vent streams are of a much shorter duration and intensity versus the longer duration and more explosive E12-6 exhaust vent stream is.
Also notice the sparks flying from the 2 E12-0 ie flaming particles.....@ 2:21.

compare 2:21 to about 2:45

Just to clarify, those boosters on either side are D12-0s, not E12-0s, though the burn time seems only slightly longer for the E12-6 in the center. He states that they are D-motors if you listen clearly in the video above, and it's stated (and also written in comments) in their longer video available at: .

This is only a technicality, however, because they're both 24-mm motors and an E12-0 flame-forward would look similar to a D12-0. Very clear that a lot of flame flows from the unrestricted/uncapped forward end of the booster at propellant burn-through. It would have been really nice if they had done these static tests mounted horizontally so you could see the actual shape and size of the booster flame envelope coming out of the pipe! Might need to video one finally...

 

[shockie]

Just to clarify, those boosters on either side are D12-0s, not E12-0s, though the burn time seems only slightly longer for the E12-6 in the center. He states that they are D-motors if you listen clearly in the video above, and it's stated (and also written in comments) in their longer video available at: .

This is only a technicality, however, because they're both 24-mm motors and an E12-0 flame-forward would look similar to a D12-0. Very clear that a lot of flame flows from the unrestricted/uncapped forward end of the booster at propellant burn-through. It would have been really nice if they had done these static tests mounted horizontally so you could see the actual shape and size of the booster flame envelope coming out of the pipe! Might need to video one finally...

I must have mishear him say E12 instead of D12 because I am hard of hearing. Thanks for pointing that out. Nevertheless, did you notice the puffing behavior on the D12 on the right hand side? It appeared to puff 4 or 5 times ......

 

[SharkWhisperer]

I must have mishear him say E12 instead of D12 because I am hard of hearing. Thanks for pointing that out. Nevertheless, did you notice the puffing behavior on the D12 on the right hand side? It appeared to puff 4 or 5 times ......

D, E, both sound a lot alike. Good eyes, though. And the motor burn times weren't all that different across all 3 motors, even though the D12 should thrust for only1.6 seconds and the E12 for 2.7s--it sure didn't look like a full second difference in burn time to me, or even close. But you can see the D's are 2-3/4" long if you pay close attention chubsters when he's loading them.

Good call on that right D12-0 chuffing--some type of grain imperfection because that sure wasn't a smooth burn--you'd never be able to see that on a rocket in flight. I've seen similar on ground tests with a new research design ("research", tsk tsk; they're just stankin' BP motors, ffs...) that had suspected poor integration of grain intervals.

 

[shockie]

D, E, both sound a lot alike. Good eyes, though. And the motor burn times weren't all that different across all 3 motors, even though the D12 should thrust for only1.6 seconds and the E12 for 2.7s--it sure didn't look like a full second difference in burn time to me, or even close. But you can see the D's are 2-3/4" long if you pay close attention chubsters when he's loading them.

Good call on that right D12-0 chuffing--some type of grain imperfection because that sure wasn't a smooth burn--you'd never be able to see that on a rocket in flight. I've seen similar on ground tests with a new research design ("research", tsk tsk; they're just stankin' BP motors, ffs...) that had suspected poor integration of grain intervals.

Poor integration means to me, poor consolidation of the grain during pressing each increment of powder.

I once saw a thrust-time curve of another manufacturers D motor that had a distinct saw tooth shape in the sustainer part of the t-t curve.

 

[SharkWhisperer]

Poor integration means to me, poor consolidation of the grain during pressing each increment of powder.

I once saw a thrust-time curve of another manufacturers D motor that had a distinct saw tooth shape in the sustainer part of the t-t curve.

Exactly what I meant. Integration=consolidation.

Estes does what it does pretty well, usually, but it doesn't build 'em to NASA specs, ha ha!