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Kruegon

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To be completely honest, I got tired of reading threads with no luck. Simple question.

Does the Jolly Logic Chute Release require a vent hole like altimeters?

My gut says yes. How else can it measure its altitude? But confirmation would be appreciated.
 

jrkennedy2

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Nope, it measures on the pad (or before when you power it on) which will equalize even without holes, unless you have a wicked-tight assembly. After ejection at apogee it is out in the open and can read alt there.

Then again, maybe I'm misunderstanding the question...
 

smarra01

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I would think you would want a vent hole to keep the pressure equalized so that the rocket does not separate prematurely before apogee.

.
 

cerving

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It's almost impossible to make a payload bay so airtight that an apogee-only detection device won't work. You DO need the vent holes for recording altimeters to get an accurate flight profile, and you DO need a vent in your payload bay if you're flying near Mach, especially with VMax or ST motors, because the high acceleration can cause a premature deployment due to the pressure difference between the inside and outside if the trapped air can't vent out fast enough.
 

John Beans

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All correct. Strictly speaking, no vent needed just for Chute Release. But if you also have a recording altimeter, it will need vents. And any vents you need to maintain fuselage pressure equilibrium, as noted.
 

r66astro

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I have two love them! Going to get two more. Let a guy use one last weekend (Tripoli Ft. Myers) with some great looking Estes kit bash. With G80. First flight without 1/2 mile + landing. Second flight < 50 yards.
Bill
 
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