E9-0

One more time: there is no "real" E9-0. Probably for a very good reson.

Actually, good point now that you mention it. Silly me.

Did they ever say "they just didn't work"? Or did they just decide not to sell them since the average American consumer would stupidly attempt to use them as a booster motor for a model that weighed too much for an E9-0 to lift safely?

There *were* reports that folks could not get the C11-0 to ignite upper stages. I have had 100% success with them. Of course, I tape my multi-stage motors end to end using cellophane tape.

-Fred Shecter NAR 20117

I've also never had a problem with the C11-0 (and also always tape them

-- though eons ago I had one of those Centuri pass-port staging models that didn't need it).

David Erbas-White

I would buy them but I'm afraid they aren't made anymore.

Kurt

Actually,

The statement below is really not an option with a small model like the Zenith II. Got very addicted to completing successful flights in the moderate sized field I fly out of. Have the Xavien electronics bay and want to do a dual deploy USR Banshee with a Perfect Flite MAWD. The sim said with the D12-0 and C6-7 combo 1925' for the Zenith. I used my field elevation, temperature and my best estimation of the winds with my Kestrel anemometer. We all know winds aloft could be different but I had the ideal winds from the southwest for the geometry of the field I use ie. municipal driving range. At 0700 Sunday morning, not many golf guys out and they get a kick out of seeing the models fly. Had two watching Sunday although they were more interested in talking to one another than hitting balls. Had to do a roughly -12.5 declination of the launch rod to compensate for wind An E9-0 (if it was available:)) would put the model up to 2629' with the C6-7. Am just reporting what the sim says. We all know in the real world the actual flight would be different by several percentage points. The model still would have landed in my field. Oh I have a 10kg scale I can weigh my models on so I use my real weight and CG. None of the manufacturers like to report weight including paint!! Did my Loc Aura on a G80-10 the same day. Rocksim gave an estimate of

3800 to 4000'. I don't remember the estimate of the rod angle. Saw the 12' streamer deploy and it started drift> :-)

Is the E9 still an option for the booster with the timer and the 9v nicad?

"Howdy" a écrit dans le message de news:9xiOe.48567$ snipped-for-privacy@tornado.rdc-kc.rr.com...

You can expect the timer, small mounting, and an appropriate battery to weigh around 60 grams (2.1 ounces). A C6-7 (for the upper stage) weighs

24 grams (.85 ounces). An E9 weighs about 65 grams (2.3 ounces). That's about 5.5 ounces, or a little over 1/3 of a pound (149 grams). That only gives you about 30 or 40 grams to work with for the rockets and their recovery systems, assuming a strict 5:1 average thrust-to-weight ratio. There's a little safety margin in that the E9 has a 19.47 Newton thrust spike in the first roughly 1/4 second.

I've flown the whole setup successfully with D12s, and with a wide safety margin on an E28. I think the E9 sounds kinda borderline for this setup - I wouldn't do it in any significant wind. But I don't have a lot of experience with E9 motors, with only about 16 launches on 'em. More experienced hands may have a better idea.

I've never built a Zenith, so I'm not sure of the BT size, but it sounds like the best solution for BP altitude is an E motor in the sustainer, not the booster.

I'm guessing a 24mm would fit in the BT since it has a D booster (BT-50?).

A D12-0/E9-8 launch outta put it out of sight for a bit, even if it needed a little nose weight.

I use about 12' of metallized mylar about 6" wide but attach it around the shock cord at the halfway point--dual 6' streamers, about a 15' kevlar shock cord and may even wrap the streamer. I think I may even wrap the rolled up streamer with a few turns of shock cord so that (hopefully) it'll unroll after all the shock cords out and as the model slows down as aerodynamic fluff. Not sure if it actually deploys as intended by my recovery record for the G80's & G125's in squatty Black Brant designs has been pretty good. Always leaving parts of streamer up on each flight.

Just trading notes...

Andy