ScrapDaddy
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- Jan 26, 2010
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I was wondering why propellant grains are the way they are in commercial motors sometimes:
1) Is there a reason the AT 29/40-120 F motors are a single ~32gram grain of propellant rather than say a pair of 16 gram grains that could be shipped USPS?
2) Is there a reason larger motors couldn't be broken down into multiples of 30 gram grains? (I know HAZMAT becomes a smaller part of the cost of larger motors, and people who fly these motors usually have access to an on site vendor, but this is just for hypothetical sake)
3) If there is a reason that propellant grains have to a certain length and this results in grains that have more than 30 grams, couldn't you make the c-slot bigger so there is less propellant to get it back under 30 grams if you were close (I'm inferring that this would increase burn rate, but I'd rather have an F30fj where i can buy without haz mat than an F22FJ where I do)
4) I get why Warp 9 motors like the H999 or I1299 don't have ejection charges(they will get snuffed out by the rapid burn), but why do the end burning ones (like an I59) not have it?
I only have a fairly basic understanding of motors(as you can tell from my questions), and was just curious about these things. If any of these questions are too specific and should be removed and belong in the research forum please let me know and I'll edit them out.
1) Is there a reason the AT 29/40-120 F motors are a single ~32gram grain of propellant rather than say a pair of 16 gram grains that could be shipped USPS?
2) Is there a reason larger motors couldn't be broken down into multiples of 30 gram grains? (I know HAZMAT becomes a smaller part of the cost of larger motors, and people who fly these motors usually have access to an on site vendor, but this is just for hypothetical sake)
3) If there is a reason that propellant grains have to a certain length and this results in grains that have more than 30 grams, couldn't you make the c-slot bigger so there is less propellant to get it back under 30 grams if you were close (I'm inferring that this would increase burn rate, but I'd rather have an F30fj where i can buy without haz mat than an F22FJ where I do)
4) I get why Warp 9 motors like the H999 or I1299 don't have ejection charges(they will get snuffed out by the rapid burn), but why do the end burning ones (like an I59) not have it?
I only have a fairly basic understanding of motors(as you can tell from my questions), and was just curious about these things. If any of these questions are too specific and should be removed and belong in the research forum please let me know and I'll edit them out.