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propellant weight?

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Rex R

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during my studies and elsewhen I keep running into the statement about a propellant weight of 125g...the question I pose is, does that include the delay grain and/or ejection charges? I suppose that depends on your definition of propellant. I know what I was taught by the AF many moons ago.
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Bat-mite

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No, propellant weight is just the weight of the ... propellant.
 

Rex R

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thank you. I also ran across a thread that stated that the all important NFPA excludes delay train elements(of course the DOT has different definition for propellant).
Rex
 

markkoelsch

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Rex, I thought 125 grams was the break point in defining a class 1 versus class 2 rocket. Hence one that requires an FAA waiver ( I think it is no longer referred to as a waiver) and one that does not.
 
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Rex R

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correct, the rocket exceeds the definition of model rocket if it contains more than 125g of propellant according to NFPA 1127(there are other conditions that also must be met to remain defined as a model rocket), one bit I noticed on the NAR website referenced FAR 101.22 was that if the rocket massed over 1500g then you needed FAA clearance (think waiver).
Rex
 
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