Fluorescent Tube Cover rockets

FTC

Fluorescent Tube Cover rockets (FTCs) are usually made from polycarbonate plastic and are tubes used to protect fluorescent lights. Most hardware stores in the US have them in the lighting section. There may be less expensive FTCs made from other plastics. You may want to confirm the composition with your supplier or the manufacturer.

They come in two widths: T8 is eight eighths or 1 inch, and T12 is twelve eighths or 1.5 inches. As far as I know, T12s are most commonly used for rockets. They come in either 4 or 8 foot lengths. Although several could be theoretically joined together, rockets this long and skinny can flex too much. The rocket on the left was left unpainted to detail how it was constructed.

Bulkhead Ends

Unlike making rockets with bottles, these tubes were never intended to have pressure in them, or ends for that matter. So, we'll just have to fix that. The most common ends are 20oz soda bottle necks, but PVC fittings have also been used. These are often glued on using PL Premium and are put either on the outside of the tube or on the inside. There is, of course, an art to exactly how the ends go on. You don't want them blowing off during a 1200 psi launch. This FTC has the 20oz soda bottle necks mounted to the inside.

Reenforcement

Reenforcement is required when the launch pressure will be exceeding 130 psi or so. Common types of reenforcement include wrapping the tube with Spectra of various tests and using carbon fiber. Spectra is the easiest of the two to get. Any sporting goods store has Spectra in the fishing department. Carbon fiber has to be special ordered. You also have to order a two-part epoxy to apply the carbon fiber to the rocket. The FTC on this page is spiral wrapped from both ends with 80 pound Spectra spaced at 1/4 inch. See the Spectra section for why I'll be doing it different next time.

Payload

You don't have much room. Most altimeters will fit in the tube without a problem. Cameras and video have been done but usually require dismantling the electronics and rearranging things into a more 'streamline' configuration. Your parachute and any internal recovery parts have to fit in there too.

Recovery

Recovery can be a trick if you have made a lot of 'fat' rockets and are now trying to figure out how to stuff your puffy parachute into such a tiny tube. Air speed flaps, chemical recovery and backgliding are common methods of recovering FTCs. The rocket on the left uses a syringe for chemical deployment of a parachute. Chemicals mix at apogee and cause gas to be produced. This forces the syringe open, pushing the nose cone off and the parachute out.