Sunday, January 09, 2011

Review: SpaceShipY

This is a sci-fi-style model inspired by the Star Wars Y-Wing Fighter. When I converted an Estes SpaceShipOne into the SpaceShipSqrt(-1), I had the fin set left over. Mix these fins with a pill bottle from Target, and you have the SpaceShipY. This model has a 24mm mount and is night launch ready.


The parts list:

* One fin set from an Estes SpaceShipOne
* Target pill bottle
* Loki liner and casting tube for 38mm
* 24mm tube
* Spent 24mm motor case
* Estes motor hook
* Spent 29mm motor
* Kevlar® twine
* Mini LED flashlight
* Two First Fire igniter tubes

I found that the cap of the pill bottle fits snugly in the Loki liner tube so I built a payload bay from that tube, the associated casting tube, and a nozzle section from a 29mm phenolic motor casing. I ground the cap so the mini LED flashlight (bought at Bed Bath and Beyond) fits through. Thus, you unscrew the bottle to access the flashlight. A piece of thin Kevlar® was threaded through the nozzle and was tied to a small nut, thus completing the assembly.

The body is a piece of the liner with a piece of the casting tubing at its base (chosen from the leftovers). The exposed length of the casting tube is the same as the root of the fin assembly.

I built a motor mount from 24mm tubing, an Estes motor hook, and motor block cut from a used 24mm motor case. I also made centering rings from a piece of the motor case that was cut in half lengthwise. I bent the sections of the casing open so they fit the outside of the 24mm motor mount. These centered the motor tube but didn't completely enclose it. More Kevlar® twine was threaded through the gap between these rings and tied to the mount. I then filled the small gaps with Gorilla Glue.

The fins are the stock SpaceShipOne set. I added sections of igniter tubes under each wing and another section between the wings to serve as a launch lug.

I filled the fins, primed, sanded, etc. The rocket is solid white except for the translucent red cockpit/cone. Finally, I applied some of the decals left over from the SS1 kit.

I attached a 12" chute to the loops in the Kevlar® cords on both the nose and body. Wadding was a mix of Estes and dog barf. Motor of choice for the first flight was a C11. I found that I had forgotten to add a 3/16" lug inside the center section of First Fire igniter tube. Thus the fit on the rod was sloppy. The launch was straight and stable despite the loose rod fit.

The ejection was on the energetic side (typical for the C11) and the Kevlar® loop on the nose cone broke. The nose section fell without the benefit of a chute but wasn't damaged. The body recovered as planned.

I used a baby wipe to clean the exhaust residue from the bottom of the fins and reworked the recovery harness for the nose. It had another nice flight on a C11-3 at NARAM-50. No separation that time!

I thought the rocket looks pretty cool, but then I did build it. Others who saw it seemed to like it. They especially liked seeing it next to the SpaceShip(-1). I guess the idea of using all the SpaceShipOne parts was appealing. One kit plus leftovers = two rockets.