Also, it probably did not hurt the stability margin in that I had put a small payload section at the top. I can never resist kit bashing.......

Thank you for that colorful account (that boy would have been a natural for Toastmasters International... :-) )! With its 9-second burn, the "steam machine" (FSI F7) must have turned in spectacular flights in that model--with its first stage and double Marcus boost, the gravity-turn power-prang (which the F7 was notorious for) wouldn't be a concern in such a modified Sea Strike "D!" Plus, that rocket (either "stock" or with the Marcus boosters) is a handsome model. If the new Semroc makes it, I'll buy a few.

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

I've been busy with other things and have not pursued this further other than thoughts.

What if the boosters are attached to the main airframe in such a way that they simply fall off once they have ceased thrusting? I have an idea along this line of thought similar to what JI referenced in his USR Sentra 2.7 design, except there would be no "down hook". The booster pods in my concept would stay in contact with the main airframe by means of their thrust and a fixed launch rod which would be inserted into a launch lug on the main airframe.

Obviously, all motors would need to ignite at essentially the same moment for this to work safely. A burn string tether as recommended by Doug Sams might be a good idea here as well.

Thoughts?

I would certainly buy a Retro-Repro Sea Strike D with side boosters if the new Semroc were to offer it as a complete package or as separate accessory boosters.

__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !

That's the way the Marcus booster operate. The upper hook is just in slightly tighter than the bottom one and that opens the booster in the middle and allows the streamer to come out. 0 delay engines are recommended for use. The friction of the upper hook is just enough to hold it in before launch, and then after the engines quit thrusting, air drag makes them come off.

You've inspired another thought...as well as a Retro-Repro Sea Strike "D", a down-scaled version (Sea Strike "C", along the lines of Semroc's Cherokee-"C" 'companion kit' to their Cherokee-"D" kit) could be offered with (either included in the kit, or separately available) "Mini Marcus" strap-on boosters, which would use 13 mm motors in BT-5 airframes. Also, the larger Sea Strike "D" could probably fly with four "Mini Marcus" boosters without needing much if any ballast up front.

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

I just relayed the Sea Strike "D" (with Marcus boosters) and Sea Strike "C" (with "Mini Marcus" boosters) "Retro-Repro" kits/down-scaled 'companion kits' suggestions--along with a link to this thread--to Randy Boadway at eRockets, the new owner of Semroc Astronautics. This may bear fruit...

__________________
Black Shire--Draft horse in human form, model rocketeer, occasional mystic, and writer, see:
http://www.lulu.com/content/paperba...an-form/8075185
http://www.lulu.com/product/cd/what...of-2%29/6122050
http://www.lulu.com/product/cd/what...of-2%29/6126511
All of my book proceeds go to the Northcote Heavy Horse Centre www.northcotehorses.com.
NAR #54895 SR

This could get out of control, leading to a Sea Strike E and Sea Strike F........

I saw a rocket at Danville with hook pods have imperfect ignition and the pods flew off under power and one hit Ron Schultz. He was standing right in front of me.

The top hook down is a needed safety feature.

Jerry

Was the person beaned by the wildly flying side booster pod hurt ?
If not, NUF said.

__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !