G78-4 mojave green lift off max weight.

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John Taylor

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Hello all,
I cant seem to find information on the maximum lift off weight regarding the G78-4 mojave green 29mm reload using the 29mm 40/120 hobby casing. I found the thrust curve data, total impulse and average thrust, but no info on the max lift off weight

Thanks for your help!

John Taylor
 

CzTeacherMan

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3.5 lbs is a 5:1 ratio at liftoff. Definitely no lower than that. Anything 2.5 lbs or lower is even better (7:1)
 

John Taylor

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Thanks for writing back,
It is a 4" diameter simple rocket with mid frame separation. Empty weight is 1100 grams, or about 2.2 lbs empty.
I know a G 64-4 weighs 151 grams, using that my lift off weight would be about 1251 grams,or about 2.8 lbs.
Thanks much for your help!
jt
 

John Taylor

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The below info is for 29/120 LMS G78G Im not sure if it's the same as you have!

Maximum recommended lift-off weights: G78-4G/L = 52 oz. (1474 grams), G78-7G/L = 32 oz. (907 grams), G78-10G/L = 20 oz (567 grams)

http://www.aerotech-rocketry.com/cu...uctions/MR-LMS_Loadable/g78g_lms_in_20206.pdf

Tony
Tony, I believe that motor might be different. I am using the 29-40/120 reloadable casing. I have flown many G64-4 reloads in that casing. The reload I'm talking about will fit that casing.

Thank you very much for responding!
jt
 

dhbarr

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Behaviorally quite a lot of difference there.

g76 has more zip up front and a bit more total impulse.

simfile1326_650x350n.jpg
simfile1298_650x350n.jpg
 

John Taylor

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Behaviorally quite a lot of difference there.

g76 has more zip up front and a bit more total impulse.

View attachment 391374View attachment 391375
Thank you very much. Looks like the G67 has a big hammer at the start, even more than the SU G80-4.
It looks like it would easily lift my rocket weight at 1251 grams at lift off.
Sorry to keep asking for information, I just bought a Google notebook, with a Google operating system that is incompatible with any rocket simulation program.

Thanks again,
jt
 

DavidMcCann

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I've flown 3.3 pounds in a 5.5" mini magg on a G76G.

It's about as far as I'd take the motor, but never had an issue with the setup.

G76G at 20 seconds

 
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STXFlyer

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I have flown my 2.2 pound vega on a G76, it left the pad in a hurry.
 

swatkat

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G76G is the hobbyline reload. It has lifted my 58 Oz. 3" FG kit no issues, 4 second delay. Rocksim says 52 ft/sec of a 72" rail. So it's a good lifter.
 
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