The Launch Pad Matra Magic R.550

The Launch Pad - Matra Magic R.550 {Kit}

Contributed by Bob Bernatchez

Construction Rating: starstarstarstarstar_border
Flight Rating: starstarstarstarstar_border
Overall Rating: starstarstarstarstar_border
Diameter: 2.60 inches
Manufacturer: The Launch Pad
Skill Level: 4
Style: Scale

The Launch Pad Matra Magic R.550

Brief:
This is a semi scale model of the French Air-to-Air missile. This is another one of the great mid power scale kits from The Launch Pad. This kit was of interest to me as I worked on the project in the late 1980s that qualified this missile to be carried on the F16 Fighting Falcon.

Construction:
The kit parts are of Estes quality as opposed to the heavier parts found in high power kits. Parts include two very long BT-80 tubes, one short length BT-50 tube, two tube couplers, a balsa nose cone, three fiber centering rings, nose weight, eyebolt, motor retainer clip, 3/16" launch lugs, elastic shock cord material, mylar parachute, and enough balsa for twelve good sized fins.

The Launch Pad lists this kit as a skill level 4. The instructions are well thought out and sufficiently illustrated. Templates were provided for the fins and for a body wrap. The tube coupler for joining the two lengths of BT-80 was a bit shorter than I would have liked so extra care needs to be taken to make sure that the tubes are properly aligned. The instructions call for coating the fins with some thin CA before gluing onto the model. I had a great deal of trouble with this, probably due to bad technique. This resulted in a trip to the local hobby store for some replacement balsa. On the second set of fins, I used medium CA to coat the fins. This worked much better for me, but I suspect that the problem was mine all along.

I was surprised that a model this long did not have a stuffer tube to minimize the area that needs to be pressurized for ejection. Since I was planning to fly this model only on reloadable motors, I didn't think that this would be a problem and my flights to date have confirmed this. The motor mount can only accommodate 24mm x 70mm motors, so those wishing to fly this model on the longer 24mm Econojets will need to modify the motor mount accordingly.

The Launch Pad Matra Magic R.550 Assembly of the model was pretty straightforward. The number one thing that one has to do is to make sure that the fins are aligned perfectly. Models with forward fins make this a must, and this model has two sets of four forward fins. All the fins are mounted flush to the body tube. I drilled small holes in the body where the rear fins are mounted and cut a small groove in the body where the forward fins were to be mounted.

I did make some minor changes to the kit. First, I replaced the 3/16" launch lugs with 1/4" lugs. The model is light enough that it doesn't really need the 1/4" lugs, but I used them because they're a better fit for our club's launch system. Second, I replaced the mylar parachute with a cloth one. I'm just not comfortable using mylar on a model that flies on E and F power. A third modification that I did not elect to do would be changing the forward centering ring to plywood and then installing an eyebolt to anchor the recovery system. Finally, I replaced the supplied shock cord with a longer one from my stash.

Finishing:
Launch Pad kits don't usually come with decals, but there is a drawing in the instructions that shows how to detail the model. I used trim Monokote to detail the model. Be prepared to spend a good bit of time sealing and sanding the twelve fins. Also, launch lug positioning is left to the builder so you can place the launch lugs to minimize the impact to your other detailing.

Construction Rating: 4 out of 5

Flight:
I've flown this model four times so far and ran into a bit of trouble on three of them. Liftoff is slow and majestic. Boost on all flights has been arrow straight with no hint of a roll so this is a very stable kit if you build it right.

First flight was on an E18-4 RMS. Ejection occurred 1-2 seconds after apogee and the model flew through the parachute and fouled it. I had to replace the top 4" of the model.

Second flight was on a F24-4 RMS. Ejection occurred right at apogee but didn't push the parachute out. Turns out that it spit the casing. Once again, I had to replace the top 4" of the model. I also added a second motor retention system to hopefully prevent losing the casing.

Third flight was on a E28-S. Ejection occurred just after apogee for a perfect flight. The dual motor retention method worked.

Fourth flight was on a F24-4. Ejection occurred at apogee, but one of the shroud lines snagged on one of the forward fins. Drat.

The F24-4 is the best motor that I've tried so far. The E28-S was also good, and I think that the F39-S would also be a good choice. I would not recommend using the E18-4 unless you cut 1-2 seconds off the delay.

Recovery:
With the recovery system located so far forward of the motor, wear on the system has been negligible to nonexistent. The forward centering ring holds the recovery system well away from the motor and helps provide additional stability margin.

Flight Rating: 4 out of 5

Summary:
PROs: A big model that really stands out on the range head. The model is light enough that it flies well on relatively inexpensive 24mm RMS motors. Slow and majestic lift offs gives a very pleasing flight experience.

CONs: The supplied recovery system may not robust enough for a model flying on composite Es and Fs.

Overall Rating: 4 out of 5

Flights

Comments:

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Jeffrey Gortatowsky (March 19, 2012)

Wow. It looks like this has been a real workhorse of a rocket!

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Jeffrey Gortatowsky (October 24, 2013)

I was reading your review and flight reports because I am about to build mine. Thanks. Looks like it will eat F24's. Perhaps CTI F79s if I can make sure the balance works out.

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