When I was at the AIRFest 24 launch last Labor Day weekend I met the folks at MAC Performance Rocketry. This company uses canvas phenolic airframes to build very strong rockets that are Mach capable out of the box. I liked what I saw, so I purchased their 54mm scorpion rocket kit with the 38mm motor mount. So, here is the MAC Performance Scorpion.
MAC Performance Scorpion
In the box
The kit comes with all the hardware needed to build the rocket. Not included are the recovery items such as the shock cords and the parachute (or parachutes). The fins and all the bulkheads are made with the same canvas phenolic material and it’s all polished to a shiny finish. What I really like about this material is that it has no grooves on the body tubes. This saves a lot of time when you’re finishing the rocket.
I purchased the dual-deploy option on this kit. The avionics bay included with the kit is top notch. The electronics sled in the avionics bay was made using 3 D printing, so everything fits together perfectly. I like the fact that they even assembled the threaded rods, washers, and nuts for the avionics Bay.
This kit came together very easily. The instructions were clear, had good illustrations, and followed a nice flow. As it was a dual-deploy rocket, I added a couple of shear pins to the top part of the avionics bay. The main parachute was in the upper payload bay. The fins fitted into the pre-slotted lower body tube very nicely. I tacked the fins to the motor mount tube with 30-minute epoxy. I then created fillets on the fin-to-motor mount and the fin-to-external body tube joints with West Systems 105 /206 epoxy.
For the flight computer, I used the ever-reliable PerfectFlite StratoLoggerCF. I love this computer and it has never failed me yet. I calculated the ejection charges for each bay. After assembly all the electronics without the charges, I did continuity checks on all circuits. I then shorted out the charge connections and turned on the computer. Everything checked out.
I took the Scorpion to the SLUG-RT launch in Fort Pierce, Florida. It was pretty windy, so a lot of the flyers decided to wait and see and watch a couple rockets fly before they risked their own. Having just come from the KloudBuster’s launch in Argonia, Kansas, a little bit of wind didn’t scare me anymore. So, my Scorpion was in the first mid-power rack of the day.
The boost portion of the flight went well. The drogue charge fired at apogee and the chute deployed just fine. As the rocket had weathercocked into the wind, it was floating back to the launch pads under its drogue chute. The computer was set to deploy the main at 700 feet. When it got to 700 feet, we all could see a puff of smoke, but the main did not deploy. I did not have enough black powder in the ejection charge.
The rocket landed about 200 feet from the launch pad under its drogue chute. The airframe took the hit well with only cosmetic scratches. Here is a flight profile from the StratoLoggerCF.
This was the first time that one of my rockets flew higher than predicted in the simulator, OpenRocket. The simulator was predicting 4,841 feet and the rocket flew to 4,977 feet.
Some of these shots, I grabbed from Rick Boyette’s Facebook page.
|29 September 2018||SLUGR-T Launch, Fort Pierce, Florida||4977 feet||CTI I236||No Main Deploy|
|21 October 2018||Buc's Blast 18, Tripoli Tampa Rocket Pasture||4845 feet||CTI I195||Good Flight|
The MAC Performance Scorpion is a high quality rocket kit. It was easy to build, fit together well, and is highly durable. It was worth paying a little extra to get this quality.