According to NAR's website, the altitude record for a C motor is 756m.

C Altitude 756 m 8/7/90 J Sexton

This comes out to 2343 ft. This seems extraordinarily high given that most high performance kits claim a max. alt. of 1600-1700' with a C motor. Does anyone know what this record design looked like? Any plans for it?

I don't know what the rocket was, but you can fly multi-stage rockets that add up to a C for the competitions. An example would be a B6-0 to a B4-6. I'd imagine his record was done similarly.

There is also the possibility that the long burn Apogee composite C motors were used (were they 10 mm?) instead of the black powder C's

Apogee used to sell a composite C6-4/7/10 in 13mm. I flew one once for a science fair project in fourth grade (nice, loud White Lightning motor). These were nice motors, and capable of pushing a lightweight, minimum diameter rocket to right around Mach 1.

They also used to sell black powder 10.5mm micro motors (which may very well have been the ones used in this particular altitude record). They had a full 'B' motor, a B2, which was also available as a booster. Apogee had a rocket (the Centrix) designed for this motor, as well as an optional booster stage. I think they said that flights over 3000' were possible with it in 2 stage B2-0 --> B2-9 configuration.

Also, figuring out the right optimum mass, using a piston and a tower (if necessary) can help out as well.

__________________
David Hash
NAR#77967
http://www.Semroc.com

And then there are the Eastern Block motors that could have been used. IIRC, our competitors have used their motors in competition when over there because of shipping problems with our own motors.

You should see the altitudes reached a few NARAM's ago when F Altitude was flown. I think
around 8 flights hit the one mile mark and, even more astonishing, they had 100% tracks
closed. I think it was at the last NARAM held near Phoenix, AZ.

__________________
Dave, NAR # 21853 SR.

Tripoli F motor class altitude record has been held for over eleven years by William Inman with a single use AeroTech F32 to 6,785 ft.

Honestly, I don't know how these guys do it. I don't think I could get RockSim to duplicate an estimation like that even simulating launching from Hartsel, CO where the elevation is 8,800 ft.

.

__________________
Steve Naquin
TRA# 677 L2
NAR# 85518 L2
SAM# 0052

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Hi Joelaunchman,
I see you live on Long Island, so do I where do you launch your rockets?

From what fellow competitors have told me, the altitude records in lower impulse classes are practically untouchable now for two reasons:

1) Apogee composite motors are no longer available/certed for contest use (though the mid-power ones are back and certed).

2) Many records were set out in Colorado, land of higher elevation and thinner air.

--Chan Stevens

Out east I hope. There are lots of large tracts of land out there in Suffolk County. I grew up in Nassau County, Massapequa specifically, and most of my launching took place in the moderately sized parks we had. I lost quite a few rockets in trees and to water, as many of these parks were either on bays or canals.