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My Level 1 Certification
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By Daniel Griswold

Photo Op My certification adventure started in September 2005, when I ordered a Public Missiles 1/4 Scale Patriot Missile.

My previous rocketry experience has been with low power model rocketry. As 3FNC became less interesting, I switched primarily to scale, staged, and clustered models. The PML Patriot was my first experience using epoxy, through-the-wall fins, quantum tubing, and motors larger than an "E".

Construction began with dry fitting the centering rings, motor mount, and fins. Once I determined that the parts were properly sized, I roughed the inside of the quantum tube and the outside of the MMT with 220 sandpaper. I mixed my NHP30 epoxy and attached the upper centering ring. I decided not to use the PML piston ejection system. This required widening the slot for the long nylon ejection chord to fit.

Once the slot was widened, I epoxied the chord to the MMT. Using the rear CR as a guide, I then epoxied the upper CR to the airframe. Once set, I removed the rear CR, and epoxied the G10 fiberglass fins to the MMT.

Then next day, I created epoxy fin fillets and epoxied the rear CR mount to the MMT and airframe. I epoxied the plywood bulkhead to the coupler, and connected the coupler to the upper airframe after roughing it with 220 sandpaper. I attached the screw-eye, washer, and nuts to the bulkhead. I drilled a 7/32" hole in the payload bay to equalize pressures during ascent. I used 5/32" screws to attach the nose cone to the upper airframe.

Once the rocket was assembled, the long task of painting the rocket began. I used 220 sandpaper to rough the entire nose cone, then washed the nose cone with soapy water. The Kilz primer bonded wonderfully to the quantum tubing and the fiberglass fins. Two small patches of primer peeled from the nosecone when I was masking for painting.

FinishedI used Krylon Fusion Red, Yellow, Black, and White for the paint scheme. I went with the "showboat" Patriot color scheme, with a white, red, and yellow nose cone and upper airframe. I painted the fins red, with a black outline. The majority of the airframe was white.

Once painted, I applied Krylon Clear-Coat to protect the week-long painting effort, and to add a nice pristine shine to the rocket.

Once again, I deviated from PML's plans. Instead of the included launch lugs, I opted for Delrin 1000 rail buttons for launch guidance. I attached the parachute to the eyelet using a simple quicklink and tied the shock chord to the eyelet as well.

For motor retention, I used three screws and six washers. My original plan was to utilize PML's motor retention, but I opted to use home-made for compatibility with Loki Research motors.

I joined the NAR in late September. Luckily, my membership card arrived early in October. With my NAR membership card and high power certification form in hand, I proceeded to the launch site. I loaded the airframe with dog barf and slid in my Nomex shield.

Next, I packed the parachute and shock chord.

My motor of choice for its maiden and certification flight was a CTI H143SS. Motor assembly was easy; the Pro38 casing was borrowed from another flyer. This was my first experience with reloadable motors. I drilled out the delay grain using the ProDAT tool. I subtracted 5 seconds off the 13 second delay. I installed the Pro38 motor, and tightened the retention.

My H143SS-8 powered Patriot was ready to rock.

RSO Table

Next was the march to the RSO table. My rocket weighed in at 4.6 lbs. I filled out the flight card and submitted to the RSO for approval. PASS...

PadNext was on to the igniter prep table. The CTI-provided ematch threaded into the motor easily, and I capped the nozzle.

On to the pad… I lowered the launch rail and slid the Patriot down. Erecting the launch rail, the consensus was a 5 degree angle into the wind. We paused for the photo op before proceeding to attach the clips to the igniter.

The walk to the LCO table was long. Every step of the way, I thought, "I hope I didn't screw anything up."

I stood next to the LCO table as the certification flight was announced. The LCO took his time to guarantee that every man, woman, child, and pet was at attention, and to prolong the "did I screw anything up" feeling. After a few more prolonged, suspenseful moments, Lift-Off"Going in 5...4...3...2...1..." The ematch lit, and in a towering pillar of thick black smoke, the Patriot rose.

Motor burnout occurred; the rocket continued to climb as a thin white smoke trail was visible. The rocket tilted at apogee and ejection occurred just as the nose cone tilted downward. The chute deployed and opened. We watched as the rocket descended in the 15 mph winds. The rocket passed over the flight line and landed 300 feet behind the flight line.

The Patriot suffered minor damage to the paint from the asphalt recovery. With successful recovery, I was L1 certified. After a few minutes, I decided I wanted to launch the Patriot again. I grabbed my Estes M104 Patriot, prepped the recovery, and loaded an A8-3 motor- only appropriate considering the successful high power flight. Thank you

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