Brief:
I wanted to go a little crazy for this stage of the EMRR 2009 Challenge.

I've always been a big fan of "Odd-Rocs" and decided to combine two of them. The rules called for a kit-bashed two-stager combining two available single stage kits. I looked at a few online catalogs and these two won out:

• Booster: Squirrel Works Pie In The Sky
• Sustainer: West Wayne Rockets Birdie

Both models were ordered through Uncle Mike's Rocket Shack, the only distributor that carried both models on a single website. All arrived on April 16, 2009.

Modifications:
Birdie Construction:

I ordered the blue Birdie kit, however, it'll be painted black to better fit the model's name.

Before any construction, I washed off the shuttlecock with a toothbrush and dish soap to remove any molding release. The paper trim ring (beneath the nose) was peeled off and the nose was masked to remain white. The paint stuck well on the flexible Birdie body. I thought it might flake or release off the surface.

STEP 1. I checked with a "T" (13mm) engine and had to recess the wooden engine block disk by 1/32" from the top. This two-stage configuration requires the Birdie's engine to stick out the rear by at least 1/8". It slides inside the wider booster engine.

In STEP 2 instructs you to fillet the centering ring with CA when it is in position. I decided to touch small amounts of CA to hold the ring in place then fillet with white glue.

STEP 4 said to use remaining epoxy to fillet the centering ring/engine tube joint. As explained earlier, I used white glue. I couldn't see using epoxy here, as it was too involved and messy for a simple low-powered build.

The only place where the epoxy is needed is where the top of the engine mount meets the inside of the Birdie nose. There was a bit of "play" at the top of the tube. The BT-5 is smaller than the inside diameter of the Birdie nose cavity.

The wood engine block disk butts up against a rounded rubber post holding the blunt nose on. I added a 1/4" section of expended engine casing over the top of the engine mount tube. It helped center the top of the BT-5 in the nose.

Pie In The Sky Construction:

The engine mount construction was straightforward. I glued the launch lug to the side of the engine mount tube, and I left out the engine block for now. For the Pizza to be a booster and allow the both engines to be joined, I'll have to glue the engine block at the bottom (not the top) of the engine tube.

The bottom of the 13mm (A10-3T) sustainer will friction fit inside the top of the 18mm (B6-0) booster. No tape or separation of the engines. The smaller sustainer will slide 1/8" into the top of the booster.

I won't glue the booster engine tube in place until both models are nearing completion. On the Pizza booster, the engine mount tube will extend out the top of the flat disk to mate with the Birdie's engine. Remember, the booster's engine block ring is moved the to bottom of the engine mount tube.

The bottom and sides of the disk were painted with Wal-Mart Aluminum spray paint. The engine tube and lug were sprayed gloss black.

The instructions direct you to peel and stick the pizza decal to the disk after the engine tube is glued in the bottom. As my engine tube sticks out over the top of the disk, I stuck it in place before the engine tube was glued on. There is not much direction on how to center the decal. I have labeled many CDs in the past and knew I only had one chance. I peeled off the backing and set the decal sticky side up on my thigh. I turned over the disk, bottom side up and lowered the disk over the stick decal. I could look through the (bigger) round motor tube hole and on to the smaller sticker hole. The sticker hole is smaller than the wood disk hole. I lightly rubbed the sticker decal into place. I opened up the decal hole to the diameter of the motor tube. Remember, on this two-stage model the booster engine will extend above the top of the pizza disk.

With the two stages joined, I knew the two different launch lug placements wouldn't line up. With both engines in place, I joined the two stages. I dropped a launch rod through the top of the Birdie lug down onto the top of the pizza. I spun the rod and made a light mark on the pizza, then drilled a 1/8" hole to allow the rod to pass through both stages. No lug is needed on the Pizza booster as the rod will pass through the disk hole and continue up into the Birdie launch lug. Using both engines as a guide, the engine mount tube slides through the disk and extends up 9/32" over the top of the disk.

The engine tube felt a little wobbly going through the disk. I added a fiber 20/50 centering ring under the disk. It was split and a small wedge was cut out to fit around the original lug. It stabilized the tube and gave me a larger surface area for gluing.

Construction:
Both were off the shelf (online ordered) kits.

Birdie Parts:

• BT-5 Engine Tube
• 13mm Wood Disk Engine Block
• 5/60 Wood Centering Ring
• 1/8" Launch Lug
• Plastic Shuttlecock
• Directions

Pie In The Sky Parts:

• BT-20 Engine Tube
• 18mm Engine Block
• 1/8" Launch Lug
• Pizza Pan Disk
• Pizza Sticker Decal
• Directions

There is only two photographs in the Birdie instructions. I've built a few Birdie clones over the years and know the construction well. But a first timer might have problems figuring out the step descriptions.

The centering ring launch lug hole isn't in the correct position. I widened the hole towards the BT-5 so the lug would be straight going through the top of the Birdie body.

Flight and Recovery:
Earlier the engine block was glued into the rear of the booster mount. The Quest B6-0 was secured through the top of the Pie with masking tape. It was a little harder than normal to get the igniter into the recessed booster nozzle.

The A10-3T was slid into the Birdie and both engines were "socketed" together. Both stages were rotated so the Birdie lug and the drilled hole in the Pie top were aligned.

The April R.O.C.K. launch was canceled because of fire warnings. I wanted to get this thing airborne so decided to fly and check stability at a local school yard on Friday, April 24. First flight was on B6-0 to A10-3T. It's stable! The Birdie really moves with the B6-0 kick start.

The sustainer Birdie veered 10 degrees off vertical into the west. After ejection I lost sight it. I thought for a moment it might be lost, but I found it closer to the launcher than I would have thought. It landed 200 feet from the pad.

Second flight, same engines. This time straight up. The second flight seemed a lot higher than the first. Both booster and Birdie landed within 25 feet of the launcher. Now that I know it's stable I'll get a third flight in at the May 2 Orlando R.O.C.K. launch.

Summary:
PROs: Simple build and a new fun configuration. I was nervous at the first launch not knowing the stability. It flew surprisingly well.

CONs: None really except for some expected minor blackening (from the sustainer engine) on the Pizza's top.