Hijacker on a 2 x 24mm cluster?

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Captain Low-N-Slow
Jan 26, 2010
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Sorry if this is the wrong forum. Does anybody know how well the Mercury Engineering Hijacker would do on a 2 x 24mm cluster? I've never done a cluster rocket before, and would really like to try one. I know the Hijacker has a single 29mm motor mount, but it would be easy enough to put one of Mercury's cluster motor mounts in it. I really like the Hijacker kit, and it's a very good price. I'd like to be able to fly it on two C11's for small fields, and D12's and E9's for larger fields. Any thoughts?

I dont see why it wouldn't work. I fly my Grave Danger in small fields on a single D12 with a 24mm motor adapter in it. I don't know about C's, but two D's should do the trick. You can always see what rocksim has to say about it.
Also, the hijacker can be flown on a single 24mm E with an adapter, so I am sure a cluster would be just fine, but if you are looking to just park fly it then I would just buy an adapter.
I just ordered the Hijacker and a 2x24mm motor mount. I can't wait, it's going to be fun! I emailed Solomon, and here is his reply:

The hijacker will fly to about 120 feet on two C11-3’s, but be sure to use a 72” launch rod because it is moving pretty slow and at altitudes under 200’ things can get a little hairy. D12-3’s will put it up to 350’ and E9-6’s will put it up to 680’. E-30’s are no problem for this rocket. I would go with E30-7’s, which will put it up to about 1000’.

As far as the fin tabs, our recommendation is to cut them down so they just extend through the wall but don’t touch the engine tubes. For this size and weight of rocket you should not have any problems with the fins staying attached.
The Hijacker is a good choice for clustering, it can do 2x24mm without problem.
Did 2x29mm in a Mercury Grave Danger. Lost it on second flight with 2xG35W thought :p

For ignition i used Firstfire Jr:s. They work great if the battery is up for it (enough amps).

As Solomon wrote you have to shorten the fintabs a bit to fit the new motormount.
Make sure you dryfit everything before gluing to make sure the motormount does not block any of the fintabs.

Looking forward to seeing some buildpics. Mercery Engineering is one of my new favs for lpr/mpr rockets :)