Sport Rocketry

44 MAY/JUNE 2017 SPORT ROCKETRY low plastic nose cone). The servo will stick out 5/8". Note that the control arm must be facing you (on the left side of glider). Check operation of the system. The entire servo range must be available. Secure the plate into the tube with four dots of hot melt glue. Epoxy the radio module pod to the bottom of the fuselage. The nose joint of the radio pod should be 1/4" back from the leading edge of the wing. Linkage This is the hardest part. It must be ex- act—there is no adjustment. Cut the 1/16" carbon fiber rod to 11" long. Cut two 1" lengths of the music wire (do not use a pre- cision cutters—it will only dent the wire— use an old husky cutter). Make two mini- mum sized bends in one end of each wire (see the detail photo). Epoxy one piece of music wire to one end of the pushrod. It helps to let the glue set for 2-3 minutes be- fore attaching, to minimize working time. Fit the wire end into the servo tab; it should be "hanging down." Turn on the radio, center the trim tab on the transmit- ter, run the stick back and forth, and then leave in the middle. Fit the other wire into the rudder horn, hanging down. Use a piece of scotch tape to hold the wire to the pushrod, and then center the rudder. Ad- just the position of the wire on the carbon fiber rod by sliding the wire under the tape until the rudder is centered, and then ep- oxy the wire to the rod. Operate the radio and verify proper range of motion. Check the CG of the glider with the mo- tor module out and the battery installed. The CG must be 2.8" back from the wing leading edge. The CG most likely will need to be trimmed back. Wrap some sol- der around the fuselage, near the tail, as needed to balance the glider. Secure the balance weight in place with CA. You can cover the wings with Japanese tissue, or add some color trim with Super Mono- cote, but try to minimize the weight. Flying Check that the rudder goes left when the right transmitter stick is moved left. The AILE slide switch on the transmitter should be up (servo direction reversed). Also select Mode 1, and Fixed Wing. WARNING: The right toggle switch on the top of the transmitter must be pushed "back" or the servo range is affected. Best to glue it permanently in that position with hot melt glue. Start out with a B4-2 motor for test and trim flights. Put tape on the motor to cause a firm fit in the motor module. DO NOT wrap the streamer around the tube— it will not deploy. Instead, "fan fold" the streamer, with folds that are as wide as the circumference of the motor tube. Lay these folds around the motor module, and insert the module into the BT-50 pod. It is best to fly in winds less than 10 mph—the lower the better. Always verify radio operation on the pad before launch. A C6-3 will allow flights to about 400 feet. You will quickly get the hang of steer- ing the glider to bring it back to you! Al- ways "get a line" on the motor module when it lands to ensure recovery. It's a good idea to build some extra motor modules in case you lose one. If properly built, you will find that the RumbleBee-C is a fine, reliable performer, well suited for beginning RCBG fliers and experienced folks, too. The battery will last at least three hours, the $10 E-Flite EFLC1008 USB charger will keep it topped off. Glide weight should be about 1.6 ounces. I will be stocking some parts for this project. Email contact: johnf@apk.net You can see the original BumbleBee de- sign at this link: http://www.ninfinger.org/rockets/ M o d e l R o c k e t r y / M o d e l _ R o c k e t r y _ v02n03_12-69.pdf. NatioNal EvENts—JoiN thE FuN! NSL Alamogordo, New Mexico Memorial Day Weekend, May 27-29 Our expected waiver is 12,686' AGL, and the launch site can accommodate launches up to "N" power. We will have a special event that is a standing tra- dition at the Alamogordo launch site: the Centennial Challenge. The object is to launch a rocket at least 100" in length on no more than 100 newton seconds of total thrust for the longest flight duration. Tours of nearby muse- ums and Holloman's Rocket Sled Track. NARAM-59 Muskegon, Michigan July 29-August 4, 2017 Rocketry Festival 2017 will be held July 29 (Saturday) through August 4th (Friday), 2017. Contest Director for NARAM will be Robert Alway. An FAI World Cup event is also planned, along with high power and other fun events.

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