Change of Command

Control Line Navy Carrier

YOU HAVE LIKELY NOTICED a new but familiar byline for the "Control Line (CL) Navy Carrier" column this month. I have again taken up authorship of this column after retiring from the duty 5 years ago. For the last 5 years, John Vlna has worked to keep you informed about our CL Navy Carrier event, and I offer him my sincere thanks for taking on the task of writing this column and continuing the tradition that began with the second issue of Model Aviation in its then-new format back in August 1975.

For those who do not know me, I started building my first Navy Carrier model, Clair Sieverling’s Martin AM-1 Mauler in 1967 while in college, but I didn’t have an opportunity to fly in competition until the U.S. Air Force sent me to Arizona in 1969, in time for the 1970 Southwest Regionals. There, I became thoroughly "hooked" on Carrier with the Chandler Balsa Bugs model airplane club.

Multiple clubs in the Southwest were active in flying Navy Carrier, and I was fortunate to be able to compete with—and learn from—modelers such as Roland Baltes, Marvin Martinez, Tony Naccarato, Ron Duly, Ted Kraver, and countless others.

After the Mauler, all of my Carrier models have been original designs, and I’ve been fortunate to have a few of them published. I have been active in the Navy Carrier Advisory Committee to the CL Contest Board and have been a member of the CL Navy Carrier Contest Board since it was formed.

If you have a topic that you’d like me to cover in this column, please contact me at the email provided at the beginning of this column.

2.4 GHz for Throttle

I have received questions about using an RC transmitter for controlling throttle and other functions on a Navy Carrier model. The ease of setting throttle travel and rigging the mechanisms is an improvement over a three-line control configuration.

This is a multichannel programmable transmitter conversion by Eric Conley. A new battery box with a switch replaces the original base of the transmitter.

The weight and drag of two lines are close to that of a three-line system. The cost to get started is only slightly higher, unless you are making a complete conversion to electric power, but continuing operational costs after the initial acquisition of all of the electric power components are lower (especially considering the current cost of fuel and glow plugs). I’ll outline some of the basics.

If you are controlling an electric motor, the ESC plugs right into the throttle socket on the receiver. The ESC will power the receiver. If you have any other functions to control with the "steering" channel, or with a third channel if the transmitter is so equipped, the motor battery will power the servos as well as the receiver. It couldn’t be simpler!

If you are running an internal-combustion engine, you will need a separate battery for the receiver and servo(s). You should be able to find a battery box that will suit your needs at any electronics parts store or even someplace such as Hobby Lobby if your local hobby shop can’t help. I hope you still have a local modeling-oriented hobby shop!

The author’s conversion of a simple two-channel transmitter preserves the original battery box.

The force required to operate the throttle or release a hook is quite small and can be generated by a mini- or even a micro-size servo. Flaps might need a little more power. Talk to your RC friends for hints on installation, wiring, etc.

For an airborne battery, I use four AAA NiMH cells. The cells are rated at 800 mAh, the same as the AA NiCd batteries that we used long ago. The weight of my battery pack is less than 2 ounces. There is little weight penalty if the battery pack is located in the outboard wing and takes the place of all or part of the normal wingtip weight.

The charger I use for my power batteries can be programmed to charge NiMH batteries, and doing everything at once is quite convenient. AA alkaline cells are also an option, but that would require regular access to the battery box while the rechargeable receiver battery option requires only access to the plug.

The "steering" control potentiometer was moved to the left side, the centering springs removed, and the wheel was replaced with a knob.

The most common question is how to convert an RC "surface" 2.4 GHz transmitter to a control handle for use in CL events—especially CL Navy Carrier. The first thing to decide is whether you even want an integrated transmitter/control handle.

I started out using the integrated approach and I still fly that way, but I’ve found it quite convenient to keep the transmitter separate and hold it in my left hand. That way, the transmitter doesn’t have to go through a pull test. It can be with you when you are starting the engine, in the pits, or in your shop.

I’ve been flying three-line handles for a half century. Transitioning to operating the throttle with the left hand and flying the model with the right seemed unnatural at first. It’s not a direct transfer of the skills you learned using a three-line handle, but it’s an easy transition to make.

John introduced me to operating with a separate transmitter and handle, and I like the convenience. You don’t get to use two hands on the handle during high speed, but pump a little iron, and you’ll be fine!

The photos show a couple of conversions for reference and ideas. The transmitters are both from Spektrum. I have had no problems with any of the Spektrum units I’ve used. The black one uses 1 × 1/8-inch thick aluminum stock from the hardware store. It is soft and easy to work with and shape. It’s also easy to find.

Eric Conley made the silver one using 4-inch square by 1/8-inch thick structural aluminum extrusion. It’s an elegant solution, but the extrusions can be hard to find—especially in lengths of less than 10 feet. If you have a local supply yard for such things, you might try its scrap pile. One of my local shops sells odd pieces by the pound. You might get lucky. A large Dremel cutoff wheel makes quick work of shaping the plastic parts—after all of the internal parts have been removed, of course.

On the black unit, I wanted to use the steering channel for releasing the lines and hook. I removed the steering wheel and spring centering mechanism and installed the potentiometer with a knob on the opposite side of the transmitter. A switch might be more convenient for some actions than a knob. Just put a resister of the same resistance and power rating as the potentiometer in place of the potentiometer in the wiring and use the switch to short across the resister.

Whatever approach you decide to use, I think you will enjoy using RC for your throttle and auxiliary functions.