The Custom Matra is a cool faux-missile rocket with a difference that might not have been completely obvious to anyone checking out the picture in the catalog back in 1994-95. It has seven fins, set in a four on the bottom, three on the top pattern. While I doubt that this oddity would detract from the rockets performance, it would never sit well in my mind, so I had a decision to make. Would my Matra be an eight fin rocket or a six fin rocket? Simple decision, really.
The Matra makes use of the same design feature that the Custom Bullet uses, a section of one-size smaller tube between the main body tube pieces. In the Bullet kit the gap was bridged by four smaller tubes that look like they were meant to be fuel cells. The Matra had four fins mounted in the gap. This oddity would have been just that, had it not been for the three main fins mounted aft. I have nothing against odd-numbered fins on a rocket, but not three up and four down. That meant either addition or subtraction, and since I was using the original die-crunch fins, I subtracted. My Matra would be a 6 fin bird.
When I opened the package I found the main BT-60 tube badly crushed on one side, something that had been impossible to tell previously because of the packaging. (It was an Ebay bird, and the seller offered to replace the tubes, but I could see no way that he would have known about the damage before the sale, and the post office had been unusually brutal with deliveries around that time.) Since I needed a full length BT-60 and wanted to make the bird E-capable, I used a Hobby Lobby coupon to pick up an Estes Vagabond, as I needed a PNC-60RL for another project anyway. And since I was changing the fin number anyway, I decided to add some length to the top of the rocket, turning a 3" parachute tube into a 6" parachute tube.
Finishing was a fairly simple prospect. After priming with Valspar primer, tube spirals and balsa grain were eliminated with two coats of thinned Elmer's Carpenters Wood Filler and two rounds of sanding. The entire rocket body was then sprayed with Testors Model Master Italian Red. The upper and lower body tubes were then masked off and the upper fin section was sprayed with Valspar gloss white. The nose cone was sprayed with Model Master black metallic, which seemed to be my go-to paint for black nose cones that summer. The decals had me worried because of their age, but after two light coats of Testors decal bonder they applied just like a factory fresh set.
First flight was at the TORC cornfield in South Charleston, Ohio on an Estes E9-4. It was a brisk spring day with the normal wind, so I expected some issues with the flight path of the Matra, which I got. The reviews I'd read previously said that the Matra sometimes had a less than dead straight flight path because of the odd fin configuration, but I guessed that the fact that the fins were so far forward caused the instability. Yep, I got a wiggly flight, but it was a very gentle corkscrew that I decided I could live with. It also windcocked, but so did everything else that was flown that day. Life in the central Ohio corn.
The second flight took place at NARAM 55 on Tuesday just as a monster storm cell was moving into the area. Past experience should have dictated that I pull her down and wait for Wednesday, but I'd spent a lot of the day playing RSO and REALLY wanted to fly something. Bad idea, and the Matra wasn't my only rocket on the rack. Loaded on another E9-4, I expected a flight much like the one earlier in the year in the central Ohio wind. The northern Ohio wind was blowing from behind us, which lead me to expect the Matra to windcock back over the flightline, which would give plenty of clearance when it came time for landing. The Matra again wiggled like the first flight, but without a trace of windcocking. It again topped out around 1000', WAY too high for the proximity to the woods. After the straight, wiggly flight, the Matra popped the chute and began a speed run toward the woods at the back of the range. It cleared the trees with 100+ feet to spare. I never even gave finding it a thought, so high and deep did it seem to be sailing. Oddly enough, it turned up in the lost and found after I left from NARAM. I've yet to make the connection to retrieve it, but there's a chance that it may wiggle its way into the sky again.
Pros: Vintage Custom, an impressive bird from their coolest period.
Cons: 7 fins? A 3" parachute tube? Wiggly flights.
The Matra is a military "style" rocket that boasts a "scale-like design" and D-power. Construction was typical of "level 3" builds with balsa fins and paper tubes. This model has a small fin area about two inches from the nose cone. This small fin area connects the lower body tube and the very short upper body tube (see picture). Alignment of the three tube sections is critical for ...