Hawk Mountain Enterprises Jumanji

Hawk Mountain Enterprises - Jumanji

Contributed by Jack Canyon

Construction Rating: starstarstarstarstar_border
Flight Rating: starstarstarstarstar_border
Overall Rating: starstarstarstarstar_border

Brief:

A 4 inch diameter all fiberglass rocket of unparalleled quality with a silly name. An expensive, but perfect choice for a Level 2 certfication rocket.

Construction:

The rocket airframe is spiral wound solid fiberglass tubing.

The kit comes wit:h:-

  • a 60" airframe
  • a 17" fibreglass nosecone with a built-in payload bay
  • three large fibreglass fins that weigh about 9 ounces a piece
  • a 28" fibreglass 54mm motor mount tube
  • a fibreglass coupler tube used for a recovery piston system, and (2) 0.5" plywood centering rings.
  • Motor retention is provided by the highly recommended, optional AeroPack 54 to 38mm aluminium tailcone retainer.
  • Both the shock cords and piston cords are Kevlar®
  • the chute a Rocketman R9C

Alan Gorecki, Hawk Mountain's owner, also included launch rail buttons.

The instructions are adequate, but nothing to write home about.

The kit arrived promptly and was packaged well in a sturdy cardboard box. If there is one area of improvement I could find, it concerns the instructions - they're sparse and, in a few places, a little confusing. Also, there are no pictures to help guide you, either. Make certain to use the 600 degree J.B. Weld epoxy to attach the retainer to your motor mount. Then prepare the motor mount tube for installation in the airframe.

Although this is a very large rocket that requires a lot of work space for construction, this is one easy rocket to build. Firstly, though, I'll make several suggestions at the start. If you don't have a Dremel tool, get one and purchase the 60 grit sanding drums. You must rough up the fibreglass surfaces that will be epoxied and the Dremel tool will make your life so much easier. You'll also need to have J.B. Weld epoxy on hand along with the regular epoxy you may have if you decide to use the AeroPack tailcone motor retainer.

The hardest part of the construction was using West Epoxy for fillets; the fin slots were not tight around the fins, so the epoxy used on the inside wall of the airframe leaked out of the slot. Knowing what I know now, make your exterior fillets first, then follow up by doing your internal wall fillets (if you don't follow this advice and happen to spill epoxy on your carpeting, like I did, send me the address of your hospital room so I can send you flowers after your spouse tries to kill you as did mine). The whole kit went together in about three days and that was after a leisurely build. Just make sure that you sand all of the areas to be epoxied; remember, it's fibreglass, and has to be grooved before you can glue it.

Finishing:

Before you prime the rocket, you should wet sand it with 320 grit wet/dry sanding paper. Wipe any sanding residue off the airframe and nose cone after sanding, then prime. I used Duplicolor gray sandable primer on this rocket. I sanded the first two coats with 320 grit and wet sanded the final coat with 400 grit wet/dry paper.

Construction Rating: 4 out of 5

Flight:

The recommended motors are high thrust I, J, and K motors. No wadding is required because of the piston recovery system. The Aero Pack tail cone retainer was used and works wonderfully.
I never intended for this rocket to become my Level 2 rocket. I actually had started on a scratch-built fat, 7.5 inch, all fibreglass rocket that relied on a custom dealer to furnish me with a fin-can ordered in January. After waiting nearly three months and after several broken promises from this dealer (who shall remain nameless), I decided to go for it with the Jumanji.

On April 24, 2004, I drove from southeastern Virginia to Wnitakers, North Carolina to attempt my Level 2 Certification flight. The winds were blowing at around 15-20 mph during the mid-morning hours that day. I loaded the Jumanji with a Cesaroni Pro 38 J400 Smokey Sam motor along with the Aero Pack 54/38mm motor mount adaptor, carried the 10.5 pound rocket to the RSO, had it approved, then lugged it to the launch pad. Once it was loaded, the Launch Officer fired it into the sky. The flight was arrow straight, reminding me of a U.S. Army Hawk missile, right up to 2500 feet. Then, it came down majestically on the 72 inch chute.

Recovery:

The rocket drifted lazily over the only grove of trees and landed in a nearby plowed field. Upon examination, the only damage was a small tear on the edge of one fibereglass fin, possibly caused by the nose cone shoulder banging into it. So a longer shock cord may be needed to avoid such damage in the future. However, she could immediately fly again without any repair, thus I earned my Level 2 certification. Later that day, I flew her again on a Pro 38 J300 motor for another nice flight. The next day, the tear was repaired by sandwiching two small slices of 5 ounce fibreglass cloth over the area and coating it with West Epoxy. After the repair and a professional paint job by an auto repair shop, the rocket is once more a thing of beauty.

Flight Rating: 4 out of 5

Summary:

Alan does a great job of taking every great product on the market to create a kit. I just wish he had given it a cooler or more macho name, like 'The Terminator=' or 'Star Hawk' rather than name it after one of the few, lame Robin Williams' films; however, beggars can't be choosers.

Overall Rating: 4 out of 5

Flights

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