Okay, I get it will burn faster if it has more surface area to start with. But doesn't it also have to have more propellant to have higher total thrust? I figgered that was why the delay was limited to 3 seconds, cuz with propellant, 3 second delay, ejection charge, and clay cap the 18 mm casing was full, no room for larger delay. But a beautiful option for a ZERO delay booster (fingers crossed!)According to something I read a while ago, it is a "partial cored" motor.
It is old data. Unfortunately I'm having no luck bringing up the new data right now (link on NAR page is broken).
Theorizing, I'd say the volume (and associated mass) of the propellant is the same. The core at the beginning wastes some case volume, thus not leaving room for -5 or -7 delays that the C6 haveAlso interesting is the propellant weight is almost identical. ???More efficient??
Makes sense, particularly volume-wiseTheorizing, I'd say the volume (and associated mass) of the propellant is the same. The core at the beginning wastes some case volume, thus not leaving room for -5 or -7 delays that the C6 have
My understanding was that the B8 was essentially just a C5 with a shorter burn due to a shorter propellant grain. There used to be a small insert in the package and on that insert, along with instructions would usually be a graph showing the thrust curves of various Estes motors. Anyway, according to that graph, the thrust curves for the B8 and C5 were identical until of course the B8 burn out and the C5 continued.It has a slightly deeper core and slightly larger nozzle. The B8 was the same dimensions. Also a slightly lower sustain thrust due to the larger nozzle.
I was concerned something like that might happen. Reportedly today's Estes PB just is not as as good as was in the good old days. Still, the NEW C5 is welcome, and I amwaiting to see the official assay report from NAR S&T.The latest version of the C5-3 tested had a total impulse was 7.79 N-s
I suspect it occurred when Estes started producing rockets like Saturn and Redstone that needed a More modest engine but didn’t want to call it the C4 for marketing reasons.This is cool, but begs a question: if the "new" C5 has an average thrust of 5.3N, should't the "old" C6, with its average thrust of 4.7N, had been called C4 or C5?
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I don't mind doing a little mental back flip with Estes C5 being all around more powerful than C6.
But what's the history behind C6's "stretch" naming designation?
Sorry about that.Note that afadeev's comparison of time-thrust curves uses the 1995 C5 data, not whatever the current one looks like. I pinged a couple of contacts at NAR, they are aware of the broken link. Hopefully the right file will get uploaded soon.
I went to the link above. Says updated 3/14. And says MARCH 2014. So did they retest the new one or just saying it is the same as the old one?
Look again. The form is dated 2014. The testing date is December 15, 2019. These are not the same data as the older C5. I'm kicking myself for not saving the 1995 data while it was accessible on the NAR web site. I thought I had, but apparently not....I went to the link above. Says updated 3/14. And says MARCH 2014. So did they retest the new one or just saying it is the same as the old one?