Cluster-Staged BP power with Break-Away, Self-Recovering Boosters

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JOAT

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Been working over this concept model for quite some time. It's been on the bench with a few parts built thus far. I think I'm going to up the priority on this work order and get this model built. Thought it would be something others would be interested in. Perhaps others like it have been built, but I've yet to hear of any.

Here's the basics of the concept:

Start with typical 2-stage model. The booster is a linear cluster of 3, though it could easily be bumped to a Y cluster of 4 with a center surrounded by 3. The main airframe has just 1 booster motor behind 1 upper stage. This central booster can be setup for either C6 or D12 based on the expected lift-off weight. Use typical short gap staging between central booster and upper stage.

Either 2 or 3 strap on style booster sections are added around the main airframe. They are going to be powered by B4-2 or B4-4 motors (note the thrust time on should be slightly shorter than the thrust time of the central booster and the central booster must have higher impulse than the strap ons).

These boosters are much longer than the central booster stage as they must extend alongside the upper stage airframe also. Each strap on is basically it's own rocket with motor mount, nose cone, and full recovery system. However they have one large fin on the side away from the main airframe and a very small set of canard style fins at the nose that are perpendicular to the main. These are set with a slight angle (or lifting airfoil) that will be pulling them away from the main airframe slightly. The intent is that when they are released at staging, they will move away with the nose leading the way and begin to tumble outwards. Shortly after staging and tumbling away from the main, they will eject their own recovery systems.

During boost, the strap ons are held in place with a socket on the upper stage that the nose cone is pushing up into. It must hold the nose of the booster so that the outward force can't pull it free. The central booster has pin & socket type connections that securely capture the aft end of the boosters. When assembling for flight, the nose of the boosters is inserted into the upper socket and the central booster is pushed up engaging the aft pins of the boosters. The central booster should also be perfectly indexed to the upper stage to ensure the strap on boosters are parallel and in alignment with the main airframe. Misalignment here could have very undesirable effects during the first second of flight.

The 3 or 4 motors at ground level must be cluster ignited. The strap ons will burn out a bit before the center, but remain attached as they enter coast phase. When the central burns through and ignites the upper, the central booster will stage and release the aft of the boosters as it separates. The upper will now be accelerating under thrust. The strap ons are just coasting and will be left behind to start their tumble for the next second before the motor ejection activates the recovery system.

Will post photos and construction details as I go if there is interest.
 
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You project sounds very interesting. Please take photos of the build and launch.
 
I've done this several times with my Proton/Saturn - IV and similar designed rocket. A few pics below (each stage four engine cluster): Each stage has a 24 mm core & three 18 mm strapons.

FH000022_sized.jpg

100B0121_sized.jpg

FH000025_sized.jpg

l23.jpg

p1220087.jpg
 
Interesting. Are the black upper sections of each of the strapons permanently attached to the upper stage airframe?
 
I'd like to see everythign that BOTH of you are willing to post.

Very interesting!
 
I'd like to see everythign that BOTH of you are willing to post.

Very interesting!
 
I'd like to see everythign that BOTH of you are willing to post.

Very interesting!

Yes, I having a thing for strap on boosters would like to see more of both of these rockets.I would love to see more pics of your very interesting build dwmzmm do both stages have drop aways or just the 1st stage? And how do you have them held on on the sustainer if those do drop away?
 
Interesting. Are the black upper sections of each of the strapons permanently attached to the upper stage airframe?

Yes, the upper stage strapons are permanently attached. I got the plans for the upper stage from the NAR website (NAR competition design plans) of Gary Coles Roc Egglofter design:

https://www.nar.org/competition/plans/pdf/rocEgglofter.pdf

Instead of using the idea of the strapon nose cones attached to the body tube via kevlar string, I just used a paper hole puncher and glued the nosecones to the body tubes.

The flight pictured in the first several frames, the upper stage was lost somewhere over the Johnson Space Center; powered with a D12-0/3 C6-0's and D12-7/3 C6-7's upperstage, with an Astrocam payload, it flew so high up that we just couldn't see it anymore. The four ejection charges were heard, and the recovery was a 12" yellow nylon parachute, but as I said, we just couldn't see it and gave it up as lost :( . I got to build me another one!!
 
Yes, the upper stage strapons are permanently attached. I got the plans for the upper stage from the NAR website (NAR competition design plans) of Gary Coles Roc Egglofter design:

https://www.nar.org/competition/plans/pdf/rocEgglofter.pdf

Instead of using the idea of the strapon nose cones attached to the body tube via kevlar string, I just used a paper hole puncher and glued the nosecones to the body tubes.

The flight pictured in the first several frames, the upper stage was lost somewhere over the Johnson Space Center; powered with a D12-0/3 C6-0's and D12-7/3 C6-7's upperstage, with an Astrocam payload, it flew so high up that we just couldn't see it anymore. The four ejection charges were heard, and the recovery was a 12" yellow nylon parachute, but as I said, we just couldn't see it and gave it up as lost :( . I got to build me another one!!


Hey Dave, you forgot to post the picture the Astrocam beamed back from that flight...

MAN! That Astrocam was REALLY up there wasn't it??!!!!
:D Later! OL JR :)

davesastrocamclusterpic.jpg
 
Hey Dave, you forgot to post the picture the Astrocam beamed back from that flight...

MAN! That Astrocam was REALLY up there wasn't it??!!!!
:D Later! OL JR :)

Yeah, very funny, Jeff! :D Losing that Astrocam was very hard for me, as I had at least seven or eight pics from other flights that payload took (on different launch vehicles). I even returned to JSC the following Saturday after that launch and told the guard at the gate I was there to search for my lost model/payload. Spent about five or six hours struggling my way around that giant field (difficult, due to the high grass and weeds), encountered a number of herd of deers and wild birds, and nearly over did myself due to near heat exhaustion and dehydration. NASA security even once met me over at the other side of the field near a road when their security cameras picked me out in the field; had to explain again why I was there and what I was doing. No problem, they gave me another pass with a "be careful" warning.... I still ask Warren Benson from time to time if that rocket has been found since.... :(:(:(
 
Hey Dave, you forgot to post the picture the Astrocam beamed back from that flight...

MAN! That Astrocam was REALLY up there wasn't it??!!!!
:D Later! OL JR :)

ROFLOL!!! That's too dang funny. :D

Oooh you busted de waiver at JSC.... Bad boy!!! :neener:
 
ROFLOL!!! That's too dang funny. :D

Oooh you busted de waiver at JSC.... Bad boy!!! :neener:

Oh, I think the upperstage went into orbit, so no waiver violations.... :D:y:
 
Yeah, very funny, Jeff! :D Losing that Astrocam was very hard for me, as I had at least seven or eight pics from other flights that payload took (on different launch vehicles). I even returned to JSC the following Saturday after that launch and told the guard at the gate I was there to search for my lost model/payload. Spent about five or six hours struggling my way around that giant field (difficult, due to the high grass and weeds), encountered a number of herd of deers and wild birds, and nearly over did myself due to near heat exhaustion and dehydration. NASA security even once met me over at the other side of the field near a road when their security cameras picked me out in the field; had to explain again why I was there and what I was doing. No problem, they gave me another pass with a "be careful" warning.... I still ask Warren Benson from time to time if that rocket has been found since.... :(:(:(

I remember this story, Dave... you've told it to me before...

Really, sorry about your loss... I just came up with a quick joke and thought it'd be cute, didn't mean to demean the loss of your awesome rocket!

I know what you mean about losing Astrocams-- Mine decided to part company from the rocket about 800 feet above the farm one time-- WHEN IT WAS IN CORN! IN JUNE, when it's still green and SIX FEET TALL in a TWENTY ACRE FIELD! Well, I just KNEW I wasn't going to get it back, and like you, I had about 15 out of the 20 pics taken on the roll. I saw the Astrocam seperate from the rocket and plummet to earth, and saw where it landed (I thought) and waded out into the field looking for it. No joy. After about an hour of wandering aimlessly, circling, doubling back, backtracking, sidestepping, etc, I was so "lost" in relation to where I thought it landed I figured it was hopeless. Luckily my little brother was videotaping the launch and being about 9 at the time, left the camera on long after the rocket had come down, and he just happened to film me walking out into the field, headed straight for it. We went to the house and watched the video, and I saw what direction I was walking (nearly straight away from the camera in the video) and lined up the trees on the horizon with the spot I had been walking from, so I went down to the field and tried again. I knew where I started from (left the pad there) and so I lined up with the trees on the horizon and started walking towards them. Not 100 yards into the field I looked down and there it was! YAY!!!

Needless to say I got rid of those stupid rubber band shock cords Estes was so fond of from then on!

Later! OL JR :)
 
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