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Zeus-cat
05-16-2007, 11:59 PM
The NAR website has the max lift weights for all of the Estes engines with the exception of the E9 series. Anyone have any idea what these might be?

dwmzmm
05-17-2007, 09:17 AM
The NAR website has the max lift weights for all of the Estes engines with the exception of the E9 series. Anyone have any idea what these might be?

From the 2007 catalog:

E9-4 is 15 oz or 425 g

E9-6 is 12 oz or 340 g

E9-8 is 10 oz or 283 g

ghrocketman
05-17-2007, 03:35 PM
These posted weights are ridiculously optimistic.
One can lift those weights with a D12 with the appropriate delay easily (but not very high).
Unless you want to use a 6' long 1/4" diameter rod in ZERO wind, I would reduce those weights by about 30%.
According to those quoted weights you should be able to launch a 12-14 oz. Saturn V on an E9-4, yet Estes never reccommended it.
I'd never try it because it would most likely result in nearly horizontal flight with a corresponding prang.
The old discontinued E15's would lift these amounts when they did not CATO.

Zeus-cat
05-17-2007, 07:16 PM
Thanks guys. I've always thought Estes estimated a bit high, but it gets me in the ballpark.

dwmzmm
05-17-2007, 08:54 PM
I've flown the FSI 1/8 scale Black Brant - II using the E9-4 back in 2005, and it flew just fine.
Some thought the E9 wouldn't be able to do the job, but the liftoff was excellent and it reached about 700 feet altitude (eyeball estimate) with the nylon chute ejecting shortly
after apogee.

ghrocketman
05-17-2007, 10:40 PM
In regards to the FSI Black Brant Flight on an E9:
How long was the rod/rail and what were the winds like ?
I'd imagine a long and large dia. launch rod with little wind.
An E9 may do the job under optimum conditions in rockets that are not light, but throw in even a moderate wind and an extreme VEER usually results.
The E9 is a good motor that would be a great motor if they would drill a port in the grain to make it say an E25.
One can always fly light rockets with high thrust motors, but the vice-versa cannot be said; low thrust motors and high weight usually end in less than desirable results.

dwmzmm
05-17-2007, 10:54 PM
In regards to the FSI Black Brant Flight on an E9:
How long was the rod/rail and what were the winds like ?
I'd imagine a long and large dia. launch rod with little wind.
An E9 may do the job under optimum conditions in rockets that are not light, but throw in even a moderate wind and an extreme VEER usually results.
The E9 is a good motor that would be a great motor if they would drill a port in the grain to make it say an E25.
One can always fly light rockets with high thrust motors, but the vice-versa cannot be said; low thrust motors and high weight usually end in less than desirable results.

The launch rod was a standard 3/16" with 36" length. Launch took place at JSC during the
Gulf Coast Regional Meet hosted by the NASA/Houston Rocket Club (Section # 365). Winds
were pretty moderate (usually so at JSC, except in rare cases). Model was entered in the
Sport Scale event (won first!). Only issue I had with the flight was a partial zipper of the
upper bodytube after ejection due to using the thin elastic shockcord that came with the
FSI kit. I have 35 mm photos of this event, but did not have the CD disk made with the
development of the film :( :mad: as I was not "literate" in posting pics on the web at the
time. Even with the rather slow shutter speed my 35 mm camera had, I was still able to get
a good liftoff pic of the BB-II and got several shots of it returning with the nylon parachute.