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Solomoriah
03-10-2007, 02:10 PM
I can't find a reference for this rocket... what engines did Estes recommend for it? The plans I've found online don't have a high enough resolution scan of the packaging for me to read the list of engines, and as far as I can find they weren't listed in the instructional text.

CPMcGraw
03-10-2007, 03:40 PM
I can't find a reference for this rocket... what engines did Estes recommend for it? The plans I've found online don't have a high enough resolution scan of the packaging for me to read the list of engines, and as far as I can find they weren't listed in the instructional text.

From the 1970 catalog, page 49...

1/2A6-2
A8-3
A5-2
B4-6
B6-6
C6-7
B14-5

(Attachment from the Ninfinger files...)

Royatl
03-10-2007, 03:40 PM
I can't find a reference for this rocket... what engines did Estes recommend for it? The plans I've found online don't have a high enough resolution scan of the packaging for me to read the list of engines, and as far as I can find they weren't listed in the instructional text.


1/2a 6-2
A 8-3
B 6-6
C 6-7


OOP motors
A 5-2
B 4-6
B 14-5

A Fish Named Wallyum
03-10-2007, 03:44 PM
I flew mine on a C6-7 once.
Once. :(

sandman
03-10-2007, 04:11 PM
I flew mine on a C6-7 once.
Once. :(

If you flew it at VOA it hopfully found an mated with my BT-20 downscale version I flew at NARAM.

Maybe there will be more of them in the spring. :rolleyes:

Mine flew once on a 13mm A3-4.

Gone! :(

Phred
03-10-2007, 05:04 PM
I flew my BT-56 sized Sandman Special upscale version of teh SPRINT on an E9-8 once... even with a streamer, I had to walk FOREVER to get it back.....

This is a great model. It is perhaps one of the most drag efficient of the major mass market kits.

Phred

sandman
03-10-2007, 06:11 PM
I LOVE the Astron Sprint!

I do need to make a Micro Maxx size yet.

And a Goony Sprint! Hey, maybe I can make that tonight!

dwmzmm
03-10-2007, 06:49 PM
The CMR Paratrooper kit looks almost like an 13 mm version of the Estes Sprint. I've used
the Paratrooper recently for NAR contest events, such as the parachute duration events and
even for the 1/2A flexwing duration (my flexie fits perfectly inside the main airframe). Some
pics below:

The first pic is the Paratrooper ready for launch in the A Parachute Duration event with the
original CMR piston launcher. The piston worked, but the model suffered severe tipoff and
didn't get a good time. Second flight was done without the piston.

The second pic is the Paratrooper on the pad with the flexie fully enclosed ready for launch
in the 1/2A Flexwing Duration. Got a nice, high boost on the 1/2A3-4T and good deployment
of the flexie's wings to get a good glide for first place. The last pic is the flexie as it was found on the pavement downrange after the flight.

The Sprint & Paratrooper design is definitely one that maximizes performace with the ogive
nosecone and corresponding boattailing. Maybe these kits should be brought back...

Solomoriah
03-11-2007, 12:40 PM
Wow, thanks for the assistance!

ghrocketman
03-11-2007, 10:08 PM
I have flown mine on a C6-7 SEVERAL times in large fields....never lost it either.
The B14-7 (or B8-7) is a much better choice than the B14-5 (or B8-5) unless you like longer recovery walks. With a streamer the chances of recovery failure due to ejection past apogee are very small.
Trust me on this one....use UPPER stage (old purple label) engines ONLY unless you like extended walks to get it back.

Solomoriah
03-11-2007, 10:56 PM
After suffering a nasty fin-break, I re-rigged my Sprint with a chute, so I go easy on the engines. It's over 20 years old, after all.

Didn't launch it today. Forgot to take masking tape to the field. Gah.

jflis
03-11-2007, 11:12 PM
Oh man, I love the Sprint. If you check out our Cougar 660 it resembles the Sprint, only in 13mm. We provide 3 different fin patterns to choose from and one is a downscale of the Sprint type of fin.

The great thing about the Sprint is that, assuming you can keep getting it back, it is good for at least 500 flights! :D

jim

Chas Russell
03-12-2007, 06:20 PM
FWIW, at NARCON NAR President Mark Bundick gave a session on kit bashing. He referenced the Estes TR-11 written by Dr. Jerry Gregorek. Dr. G had some of his aero students at The Ohio State University build Estes Alphas (the balsa fin and nose cone versions) with various degrees of streamlining. The fourth and last iteration had a different nose cone and fin planform, plus a boat-tail as designed by George Pantalos.
I pointed out at the Q&A that that design was the basis of the Estes Sprint.


And now you know the rest of the story...

Enjoyed Narcon!

Chas