Retro Rocket Works Spitfire

Retro Rocket Works - Spitfire

Contributed by Moira Jean Whitlock

Construction Rating: starstarstarstarstar
Flight Rating: starstarstarstarstar
Overall Rating: starstarstarstarstar
Manufacturer: Retro Rocket Works

[Rocket Pic]Brief description:
Single staged, 29mm motor rocket in all wood construction and retro looking design, much like the stout sci fi rocketships with huge swept back fins, seen in old movies.

Construction and finishing:
All the parts arrived securely wrapped in liberal amounts of bubble wrap. Nothing was broken or missing. The actual number of parts was few, as the rocket is very simple to make. The instructions were simple and clear, with few drawings, but none were really needed.

The nose cone was smooth, and was made of alternating insets of cherry and maple hardwoods. it is precisely turned and symmetrical, and the grain of the wood is beautiful. It has a shoulder of a couple inches in length, allowing a close and secure fit in the body tube. No sanding was needed. There is a metal screw eye already in place in the nose cone for the parachute and shock cord attachment.

The parachute is rip stop nylon, 24 inches in diameter, and bright orange. The shroud lines are a strong braided nylon. The shock cord is 1/4 inch thick Kevlar® type cording that attaches to a screw eye in the forward centering ring on the engine mount.

The body tube appears to be mahogany and is sanded smooth with the grain very evident and pretty.

The 4 fins appear to be basswood, with swirly grain patterns. All the fins were precut, as were the centering rings, engine tube, and body tube, and the body tube was also preslotted for the 4 fins. The fins are designed with tabs that meet with the motor tube for strong construction. They were all cut alike, 3/8 inch thick, very precise, and also very smooth on the edges. They are rounded on the continuous leading and trailing edge. The edges show that the inner ply is dark, mahogany-like. This striping of color provides a nice accent. The fins are also accented with a half-moon shape of iron-on veneer that has a mahogany-like color.

I used epoxy, as recommended, to attach them through the body tube and to the motor tube, which also is a pretty mahogany. The two centering rings are plywood. The 2 launch lugs are brass, beveled to reduce drag, and accept 1/4 inch rods.

The model came out very sturdy and strong. But I just couldn't bring myself to paint it or decal it. The wood is just too pretty. So I finished it with three coats of polyurethane clear furniture varnish.

Rating for construction and finishing: 5 out of 5, but some might say 4 1/2 because of the need for the vent hole. But this is something we should do in high power anyway.

[Rocket Pic]Flight and recovery:
The Aerotech H180-M was used, and it's one of the engines the manufacturer recommends. They also say that the G64-4, G80-7, H128-M, and H220-M are good too.

The rocket roared off the pad straight and high. When the chute ejected at apogee, it appeared to be a tiny speck. I got the rocket back about a half mile downrange because it caught a thermal and lingered high. This was particularly an anxious moment, because this was a Tripoli level 1 certification attempt. I hadn't intended to certify with this rocket, but everyone who saw it oohed and ahhed over it. People kept pressing me to launch this beauty. Nobody had ever seen a wooden rocket. Some even asked if it was real. That is, is it a display or does it fly. It amazed them when I popped off the nose cone to reveal a legitimate construction for flight. Then some were sad that I'd actually fly it, fearing damage to its looks. Even the RSO worried about damage and destruction of the beauty, as he announced that everyone should look now while they still could. Several people took photos of it. The way I saw it, metaphorically, why breed a champion racehorse to perfection and then not let him run? Besides, half of the club was fixed on me and the rocket, daring me to be bold and do it.

Everyone cheered when the flight occurred. Nothing was burnt or damaged, and the engine stayed in, held with duct tape. Fellow club members teased me about the tight loops of duct tape, saying that I wanted to hold the engine hostage. I'd seen too many other people lose motors to ejections and was paranoid about mine.

The rocket was prepped with one Nomexsquare and worm bed wadding. I first thought that the wadding was overkill, but cert flights must be perfect. Well, I was glad I did this, because the Nomexsquare was burnt in half!

[Rocket Flight]A small vent hole was drilled in the body, near the middle, on the side opposite the launch lugs to relieve differences in air pressure and prevent ejection of the motor or premature separation of the nose cone. Due to the precise fit of the parts, air pressure was evident on the ground when the motor resisted being placed all the way in until the hole was drilled.

If there was anything not good about the flight, it was that I had one hand on the launcher and the other on the camera, and consequently, I didn't capture the great moment of takeoff on film.

Rating for flight and recovery: 5 out of 5

Summary and tips:
Simple to build, performs well. A crowd pleaser. A bit expensive at $125, but worth it since I certified in style. And its manufacturer made all the parts to precision.

Don't paint it. Every club has a woodworker who would execute someone who'd mar such art as this. I recommend this beauty to anyone who wants to show off with class. In fact, I think that my level 2 project might be a scratch-build using the parts that Retro Rocket Works makes. I'm pricing preslotted 4 inch mahogany tubes now. And they make lovely 4 inch nose cones. And 38mm motor tubes!!! I'm hooked.

Any tips I learned? The vent hole in the body tube was very important in preventing premature separation of the nose cone. I don't remember seeing any mention of such in the instructions.

Overall Rating: 5 out of 5

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