Type

Warp-1 is a U.S. Rockets MPR/HPR kit that I purchased with a custom single body tube. It is a 29mm motor mount kit that includes an adapter for 24mm motors. Although the USR website says that a parachute is not included, I was pleased to find an 18" mylar parasheet in the kit even though I would not use it on a model of this type.

This is my first MPR kit and I was surprised by the mix of components. The body tube is heavy walled as compared to, say, an Estes BT-80. The fins and centering rings were, as close as I could measure, 1/8" plywood (not 3/16" as stated in the instructions). These parts were "hefty" in comparison to the modroc parts I was used to. But the shockcord was a length of flat elastic that I would only have used in a much smaller modroc.

The parts were dry fitted together and only a little sanding was needed to true up splintered ply edges. There were also some delaminated areas of the body tube at both ends due to what looked like water damage. This was repaired with some CA, some scrap wood molding, and a couple C-clamps.

Specifications
(from: US Rockets)

Warp-1

Airframe	69 mm (2.7") OD
OAL	117 cm (46"}
Weight	3.43 N stock (modified: 7 N)
Recovery	Not specified by USR. Modified to a baffled NC ejection with an 81cm (32") nylon chute.
Motors	24mm/29mm D/E/F/G/H (modified: F/G/H)

Construction Details

Motor Mount/Fin Can

The motor mount is heavily modified. It includes 20" of PML 29mm phenolic MMT, 3 ply centering rings, and a ported forward bulkhead. Several longitudinal rows of 1/8" holes are drilled into the forward end of the MMT to vent ejection gases sideways into the airframe. A CR just aft of the holes seals the aft airframe. A ported ply bulkhead is epoxied to the forward end of the MMT to allow ejection pressurization of the forward airframe. The plywood fins are mounted through-wall to the MMT itself. About 10 feet of Kevlar™ shockcord is knotted aft of the pressure CR and is epoxy filleted to the MMT. The shockcord is fed forward through a small access hole in the ported bulkhead.

	Motor mount assembly. The fins are epoxy filleted to the MMT as are the two middle centering rings. The unattached forward ported bulkhead will be glued in after the MMT assembly is epoxied into the airframe. (Click on image for full-size picture. Use "BACK" button to return.)
	MMT close up. Ejection baffle holes are visible along the forward end. Kevlar™ cord is epoxied to 6" of the MMT. (Click on image for full-size picture. Use "BACK" button to return.)

Because of the TWMM fins, I had to slot the airframe (using a sharp hobby knife). The partially built motor mount assembly was slid into the slots and the two inside CR's were epoxied in place using long bamboo skewers as epoxy "daubers". The aft CR will have two T-nuts epoxied in to provide for motor retention. An external tape thrust ring will be used for SU motors. Almost any length 29mm motor case can be used in this rocket. (Click on image for full-size picture. Use "BACK" button to return.)

Airframe

The airframe is one length of standard USR body tube. I chose the one-piece body tube in order to incorporate the long MMT/baffle into this rocket.

Nosecone

The balsa nosecone was sanded, sealed with diluted Fill'n'Finish, and sanded again. Several iterations of this produced a smooth, if not very ding resistant, surface. I may glass this NC now just to resist dents.

The nosecone was modified to accept a removable eyebolt which allows noseweight changes in order to adjust the CG after the extensive MMT mods. So far, Rocksim tells me that the Warp-1 is still (over) stable, primarily due to the weight of recovery components up forward.

Misc

A very stupid accident resulted in the loss of my prospective L1 certification rocket, the Flyin Jenni. Okay; I tripped over my own feet, knocked the rocket over, and accidentally stepped on the poor thing. She's a total loss.

But I am geared up and ready to cert, so it looks like the Warp-1 is going to be called on for extra duty. She was going to be my reloadable motor practice rocket, but now it looks like she'll do cert duty as well. Its a little light for an H motor, even the H-128 reload I plan to use, but I can stuff some additional weight in her to keep recovery issues under control (I hope). There is a rocket killing lake near my club's launch site and I have had more than one bird drift into it. The Flyin Jenni was heavily fiberglassed and epoxy painted to reduce/prevent water damage. I'll just have to keep the Warp-1 out of the water.