G78-4 mojave green lift off max weight.

[John Taylor]

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]

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)

 

[tfish]

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)

https://www.aerotech-rocketry.com/c...uctions/MR-LMS_Loadable/g78g_lms_in_20206.pdf

Tony

 

[John Taylor]

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]

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)

https://www.aerotech-rocketry.com/c...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]

Did you mean g76?

 

[John Taylor]

Did you mean g76?

Yes G76, I'm sorry, so many motors.....brain fail....
Yes I did mean G67-4 Mojave Green.
Thanks!
jt

 

[dhbarr]

Behaviorally quite a lot of difference there.

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

 

[John Taylor]

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

 

[dhbarr]

https://www.thrustcurve.org/guidepage.jsp

Enjoy!

 

[John Taylor]

https://www.thrustcurve.org/guidepage.jsp

Enjoy!

Thanks Mucho!! I really appreciate your help!
jt

 

[DavidMcCann]

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

 

[STXFlyer]

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

 

[swatkat]

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.