Rocketry Planet

Rocketry and video are two great tastes that taste great together. So it was a given that I'd purchase and build Heavenly Hobbies' Washigei front-engine, rear payload video-capable rocket. According Jose Andrade-Cora, the designer and owner of Heavenly Hobbies, a Washigei (pronounced Wash-E-Hay) is a Japanese bird.

The cool thing about this bird is its rear payload bay was designed around a Oregon Scientific ACT2K waterproof action cam with affords an unobstructed view of the ground.   

I really liked the Washigei because of its cool front-engine design and its 29mm motor mount. I also figured it would go higher using the lighter BoosterVision camera. Besides, now I would have an excuse to get another tiny video camera!

I was lucky enough to meet and interview Jose at NARCON 2009, where I asked him about his company and the Washigei. After talking to Jose, I was sold so I purchased kit #17 signed by Jose himself. 

When I got the kit home, I was impressed with the quality of the kit and was surprised to find a CD inside with an Adobe PDF of the instructions on it. In the winter I build rockets in my office, next to my computer. However, now that its springtime I have been banished to the garage and in hindsight would recommend printing the instructions out first to keep from getting glue on your keyboard as you scroll through the instructions!

The Construction

The build photos shown are taken from the PDF instructions file. You start by constructing the payload compartment lid. I used Five Minute Epoxy for the majority of the construction. The plywood centering ring fit snugly without much sanding. The kit includes a plastic bulkhead, which protects the camera and its lens in the payload compartment. I would recommend protecting the plastic bulkhead with tape or some other form of covering while the build proceeds. 

I ended up scratching it pretty good while trying to clean off sawdust from it near the end of the build . I had to drill out the center hole before its maiden voyage to get a "clear shot" through the lid. The payload compartment is the first thing to hit the ground when the rocket lands so this is an important piece, which I should have replaced (see flight-test).

The main payload compartment went together easily.  It uses an internal long coupler for reinforcement and to support the aft fins.

The lid then needs to be drilled and two nuts glued inside. Make sure you use petroleum jelly on the threads of the nut so the glue doesn't dry and clog them.

Next comes the construction of the engine compartment. This part of the build took the longest and required the most sanding and patience. The rocket uses a 29mm motor mount tube and slotted airframe for the forward fins to slide through. These fins need to be glued to the motor mount for added strength.  This step hung me up a little bit because the picture in the instruction manual didn't show this clearly. No internal engine block is used in the motor mount tube so a variety of engine sizes can be utilized.

The Washigei has a unique positive retention system called Triiceps™ consisting of a high temperature aluminum alloy retention plate with three screws that anchor the engine against the aft centering ring.

The three internal nuts have to be bent and snipped to fit in the centering ring. Again, use petroleum jelly on the threads before epoxying and hammering the T-nuts in place. This was also a difficult step and I had one come loose during construction  I think Steve Shannon has the right idea with grinding the extra metal away on the threaded T-nut inserts for better strength instead of breaking off a tab and prong off.

Next came the construction of the Amaze™ Ejection Gas Baffle, which went together easily.  Make sure the holes in the two bulkheads don't line up — I almost forgot.

Next, a screw eye is attached to center of the bulkhead and epoxy is added to the threads. The parachute compartment is constructed next. The shock cord is tied and glued to the screw eye and the baffle is glued in half way.

The nose cone comes next. A wooden peg is provided with another screw eye. I followed the optional instructions of adding .50 ounce of lead weights into the nosecone cavity before gluing the insert in place. The nose weight was recommended for improved flight characteristics if you planned on launching payloads up to 8 ounces. You won't need the weights if you plan to carry payload weighing less than 5.5 ounces.

Now the build got challenging with the connection of the engine and payload compartments via three long hardwood dowels.  Gluing the dowels to the front fins wasn't difficult. The second step of gluing the dowels to the aft fins using the recommended 12-minute epoxy is a job that takes two sets of hands.  Make sure you dry fit everything first and sand as necessary to get things to fit correctly. After all, the payload compartment will be home to all of your expensive video gear beneath all that thrust and smoke.

The final steps in finishing the Washigei involving some interesting heat-proofing of the areas on the rocket exposed to engine exhaust. First, the aft nosecone for the payload compartment needs to be blunted and covered with heat-resistant epoxy such as J.B. weld.  The aft nosecone is not glued in so you can pull it out and gain access to the camera before and after launching. The leading edge of the aft fins can optionally be covered with heat-resistant epoxy.  You can also optionally cover the aft airframe with aluminum foil or heat resistant epoxy, which the instructions state will extend the usable life of the payload compartment.

I opted for multiple coats of high-temperature paint which in hindsight did very little to protect the aft airframe from the powerful thrust of a AeroTech G77 on its second launch (see flight test below). I would highly recommend following all of the optional heat-proofing steps.

Propellant Choices

The final variable to consider before flying the Washigei is which propellant to use. According to the instructions you should choose a propellant with a relatively "cool" exhaust signature. A graph is provided and the cooler Redline and Blue Thunder propellants are recommended. Another thing to consider is how clean the exhaust is since the exhaust gases and smoke will surround the camera throughout the flight. I have flown with Black Jacks before and know how dark the smoke is, so I decided to go with AeroTech Redlines for my first and second flight tests.
 
You also have to add an external engine block before launching.

Flight Testing

On April 25th, 2009, in Durham, Connecticut, I took the newly constructed Washigei to CATO Rocketry (http://www.catorockets.org/) club's launch #148 for some flight-testing. To my surprise Jose Andrade-Cora from Heavenly Hobbies was also in attendance and even became the club's newest member that day.

The first flight was on an AeroTech F27-8R Econojet engine. I had a heck of  a time getting the Copperhead igniter into the engine but CATO's president, Al Gloer, deftly got the bugger in for me. The hole is too small for other types of igniters.

I decided to use the wireless BoosterVision Mini Gear Cam first. I figured if there were a problem with the rocket, I'd at least have the video recorded from the ground of the rocket's first and only flight. The tiny wireless video camera transmits at 2.4Ghz to a receiver I have mounted on a pipe. The receiver is wired to a small DV camera that I use as a recording deck. My son, Gus, loves to watch the live feed from the rocket during the flight on the view screen. Last year I added a +12dB Radome Range Booster antenna to the receiver to boost the range to 4000 feet.

Thankfully the first flight went well. It didn't go very high and the eight-second delay was cause for some excitement.

The parachute did deploy but the lines got tangled and didn't fully inflate. The Washigei survived its first flight with a moderately fast landing into the wet field. The camera got mud on the lens, which could have been avoided by replacing the clear plastic window in the payload compartment lid. I inspected the payload compartment and found no damage to the heat-resistant paint or epoxy. I did find a piece of the troublesome Copperhead igniter imbedded into the epoxy on the aft nosecone, which was pretty cool. I rewound the video from the flight and was pleased to see it came out great except for the moment of launch.

The video broke up a little bit from the antennas not being aligned. It also was overexposed for a moment as it lifted off the pad. I could have pulled the receiver out of the ground and pointed it like a rifle at the rocket for better reception. One advantage to using the lighter camera was that the rocket angled over at apogee and I got a great shot of the horizon and sky before the parachute deployed.

The second flight was on an AeroTech G77-10R.  Jose said with an AeroTecg G80, the Washigei should fly to an altitude of about 1500 feet. I also switched to the Oregon Scientific ACT2K camera. I hit record button, lifted the aft nosecone and slid the action cam into the payload section. The ACT2K camera can use up to a 2GB flash memory card for one hour of 640x480 digital video. One hour seems like plenty but the camera stays rolling before and after the launch. The rocket also works with the ACT3K camera that supports up to a 4GB memory card for two hours of recording time.

With the camera recording, the launch controller counted down and the rocket lifted off the pad really quick.

Everyone noticed the rocket spiraling upwards. The parachute deployed properly this time and the rocket floated down nicely on its 28" nylon parachute. The raw clip from the ACT2K camera ending up being over 25 minutes long because it took a while to retrieve the rocket from the swamp nearby. The electric match wires got hung up on the payload bay and is visible at the top of the shot from the rocket.

The rocket landed in a tree up about 10 feet over knee-deep water. The action cam is waterproof to 10 feet so I wasn't worried about the camera getting wet. After retrieving the rocket from the tree, I noticed heat damage to the payload section.

The increased thrust from the G77 burned through the high temperature paint and tore through a few layers of cardboard of the payload section. The bigger engines really can damage the payload section so I will be adding extra heat proofing. Jose recommends epoxying aluminum foil to the body of the payload compartment.

Final Thoughts

The Washigei is a neat build and really fun to fly. The video you'll get from the aft-mounted payload compartment is unique. You should follow all the optional heat-proofing the instructions to extend the life of the camera payload section. For less washed out video on bright launch days, you should add a neutral density filter to the payload compartment lid.

I also should have followed the instructions for launch rod prep, which suggests using a spent black powder engine case as a standoff for the rocket.  Unfortunately, I used a piece of wood that blocked the camera lens and caused the bright flash of light on the recording when the rocket first lifts off the pad.

I would recommend this fun bird to anyone who's into video and rocketry. Special thanks to Lloyd Langevin for filming the launch from the ground!

For Dan's contribution of this article, he will receive a free one year subscription to LAUNCH Magazine. This sponsorship is made possible by our friends at M&M Publishing, Inc., the publishers of LAUNCH. Want your own free subscription? Read the program details page for complete information.