Madcow Rocketry Hawk MIM-23B

Madcow Rocketry - Hawk MIM-23B {Kit} (K-116)

Contributed by Mike McFadden

Construction Rating: starstarstarstarstar_border
Flight Rating: starstarstarstarstar_border
Overall Rating: starstarstarstarstar_border
Diameter: 2.60 inches
Manufacturer: Madcow Rocketry
Style: Scale

Picture courtesy of Madcow Rocketry    Madcow Rocketry Hawk MIM23

Brief:
Modified for dual deploy. 24" Drogue and a 36" main. A 38mm and 1/4" plywood fins were also added.

Construction:
15.5" and 10.5" body tubes, 4 1/4" plywood fins, 1 1/8" centering ring, 1 balsa tail cone, plastic nose cone, 36" chute, chute protector, Kevlar® shock cord.

The standard Madcow Hawk is a 29mm motor with a single 25.5" body tube. Mike responded he had the components for a 38mm model. He upgraded the fins to 1/4", parachute to 36", and sent 10.5" and 15.5" body tubes per my request for dual deploy. The construction was no problem and consisted of quality parts. I wanted to build this sturdy for larger 38mm motors. I was concerned with the 1/8" centering ring so I reinforced that with some scrap carbon fiber. The body tubes were reinforced with fiberglassed sleeves from Soller composites. The fins are mounted through the wall and butted against the forward centering ring, epoxy fillets, and then foamed. I cut some slots in the balsa tail cone as it did not clear the fins inside the body tube. I also reamed out the bottom part of the tail cone with a Dremel to insert an Aero Pack retainer. After the tail cone was epoxied in place, I added tip to tip fiberglass over the fins and to the rear of the tail cone. The pieces went together without a problem other than the tail cone insert which was an easy fix. After using RockSim to simulate a J350 flight, I had to add 10oz of weight to the nose cone. This was done by pouring in some finishing epoxy, adding lead shot, and then more epoxy topped off with foam. There wasn't much room leftover in the payload bay so the eye hook would not work in the nose cone. I drilled two holes and ran a Kevlar® cord through the holes. With the added weight, a 48" chute would be best, but it will not fit so I stuck with the 36" chute. Also for the altimeter bay, I used a 2.6" setup that I had already built for another rocket. I also used rail buttons rather than lugs.

Finishing:
I used Kilz for the filler and after a lot of sanding, I sprayed a coat or two of Krylon camouflage Olive paint for the body and a flat black for the nose cone. The finishing coat was Krylon matte clear. This is not the most visible of colors, but I wanted to keep it somewhat scale. One decal with the kit showing US ARMY. Another addition was 3 holes to the nose cone for shear pins.

Construction Rating: 4 out of 5

LaunchFlight:
The maiden flight for the MIM23B was on an I357T. I was ready to stick a J500G in it, but there was too much wind...maybe next time.

RockSim indicated a flight to 2531'. This was also an opportunity to try out a new tracker. We angled the rail about 10 degrees into the 15mph wind and off it went. Great flight, and it didn't seem like the wind affected it. Everyone lost sight of it and after several nervous seconds, I saw it about 400' off the ground under both chutes.

Recovery:
After recovering it, the first thing I noticed was the tracker had been ripped from the Kevlar® cord I attached it with. It also tried to zipper but only very minor damage was done thanks to the fiberglassing. It can fly again without repair. But why did we not see it under the bright orange drogue? Turns out the ematch failed for apogee deployment so it came in at about 205mph to 500' where I has set the MAWD to deploy the main. This pulled the payload out from the booster. A few fellow fliers heard a whistle over the wind, which must have been the high speed descent. This model has the split fins so a whistle is expected at high speed. The altimeter chirped off an altitude of 3510', just a bit more than RockSim said.

I have to wonder what it will really do on a J--RockSim says 5200' on a J-350W. There's not enough room for a 38/1080 so I'll have to stick with 38/720. I also really like the Aero Pack retainer. Simplicity at its best. As far as the tracker goes, it works. We were able to locate it in the middle of the field after going back for the receiver. If it wasn't for the ematch, it would have been a perfect flight.

Flight Rating: 4 out of 5

Summary:
I am happy with the kit. I built it solid to push it to the max.

Overall Rating: 5 out of 5

Other Reviews
  • Madcow Rocketry Hawk MIM-23B By Patrick Bissonnette (May 25, 2008)

    Brief: The U.S. Army MIM-23B Hawk is another beautiful model from Madcow Rocketry. It can be purchased in either 29mm or 38mm motors options. My brother chose the 29mm because those motors would fit his budget better. This review was followed by me as my brother built most of it. Construction: The kit includes: 1 Plastic cone with eye bolt 1 Balsa tail cone 1 ...

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