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Jump To: Getting Started Wing Fuselage / Tail Radio / Balance Flying / Tuning Parts List Options Cores and More... *** Updates ***

[Courtesy of Bill Grenoble (iflyicrash "at", Denny Maize (rcsoarnut "at" and Joel Foner (joel.foner "at", this page last updated on June 07, 2003]

Install Radio Gear

There are many workable ways to install radio gear in the Terminator - what follows is one way that we have found to be easy to install, adjust and balance the ship with.

Rather than using traditional music wire pushrods, we've had great success using Sullivan #507 cables with the yellow sheaths as pushrod supports (these are the stranded cables, normally used for large ship pull-pull installations).  You may be a bit concerned about using cables for pushrods.  We were concerned too, but they work very well, they are light and they are easy to work with.

Here's the trick:  Make sure that the longest unsupported run of cable is about 1/2" with the servos in their neutral position.  This should leave just enough travel to handle full surface deflection, and with only 1/2" or so unsupported, the cables will not flex in compression.

Solder a threaded coupler on the servo end of each cable.  The V-Tail end gets a z-bend.  Some builders prefer to solder the coupler end first, and then do the z-bend at the tail, while others prefer to do this in the reverse order.  Either approach will work fine.

Here is a picture of how the v-tail control horns look once everything has been installed:
tailcontrolhorns.jpg (39079 bytes) V-Tail control horns with cable linkage (click for full-size image)

The Terminator fuselage is designed a bit larger than the "hotshot" HLG fuselages to make radio installation easier.  If you are using Cirrus CS-20's, CS-21's or another servo of similar size, you will be able to mount the servos either stacked parallel to the bulkhead or in a row parallel to the fuselage sides.

Mounting the servos stacked parallel to the bulkhead will allow you more adjustment range of the CG, and will make it easier to reach up front for moving things around, but it's a little trickier to reach in for adjustments.  Check the length of your servo arms, and trim the excess arm length so that you attach the pushrods to the hole 9mm from the servo arm pivot point.  You will not need more throw, so you can discard any length over this length - it will just make it harder to fit things in if you leave the arms longer!

servoinst.jpg (46329 bytes) One approach to servo positioning (click for full-size image)

V-Tails must have more down travel than up to work correctly.   We've found that with CS-20/21 servos, moving the servo arm one 'click' ahead gives the right throw offset.  To do this, center the servos with your radio on, and attach the servo arms so that they are at 90 degrees to the fuselage centerline.  Then take each servo arm and re-attach it one "click" ahead - so that the arm is one notch closer to the front of the plane - than the normal 90 degree position. 

If you use a servo arm of the length described above and V-Tail control horns of the length shown on the plans, we've found that setting your transmitter throws to around 100% gives a decent control feel.

  • Remember that V-Tails need more down than up travel, typically 2:1 for down:up travel.   You can obtain this either by setting the travel endpoints in your radio or by setting the arm angles on the servo and ruddervator control arms.

Terminators have flown successfully with either 110 mAH or 150 mAH packs.   By moving the pack around, either one can usually result in a balanced ship without nose or tail weight. 


The Terminator has a wide balance range.  If you are a beginner, try balancing the Terminator about 2.5" - 2.75" from the leading edge of the wing.  If you have flown HLG's before, or are used to a more sensitive ship, start with 2.75" - 3" from the leading edge.  We use 3" from the leading edge as the "right" balance point for a performance-trimmed ship.

If your Terminator is balanced at 3" from the leading edge, and the nose seems to "ride high", then you may need to reduce the wing incidence (add a 1/16" shim under the rear of the wing trailing edge and try again). 

If the Terminator tends to "tuck" on a very hard launch, try adding a small shim under the leading edge of the wing, or reducing the amount of shim under the trailing edge of the wing.  Another possible reason for this behavior is a tail boom that is not rigid enough.

Another way to tell if you need to change the incidence is to look at your elevators at the end of a flight.  If the neutral position of the tails is slightly down, then you need to shim up the wing trailing edge a bit, and vice-versa if the neutral position is slightly up.

Jump To: Getting Started Wing Fuselage / Tail Radio / Balance Flying / Tuning Parts List Options Cores and More... *** Updates ***

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