2.6m Yak-55SP Recommended Equipment List


This list will help you cost up a 2.6m Composite-ARF Yak-55SP. You may of course have some of these items already which will reduce the total cost.


The list is not a definitive collection of what you must buy but is simply a list of parts that many Yak pilots are using with great success and reliability.


You can of course substitute your own preferred brands/preferences where applicable but as stated above these parts have proven a success time and time again.


I have added an 'Available From' column for the more 'specialist' parts your local model shop may not hold to save you time trying to hunt down suppliers!!



Item Image Description

Approx Cost (£)

Available From *


2.6m Yak-55SP Kit £999.00




There can only really be one choice here and it has to be the Desert Aircraft DA-100. Reasons for using this engine in your Comp-ARF Yak include supreme reliability, a proven history, sheer power and the fact that the airframe was designed around this engine.

There are obviously other 100cc engines available but you will need to make you own modifications regarding carb placement, throttle servo placement and will probably need to jiggle with other components to obtain the recommended CofG position.






spinners 4.5" or 5" Carbon Spinner. Although quite expensive, a carbon spinner is recommended to help keep the weight down. To give you an idea, a 4.5” spinner (which looks ‘right’ for this model) weighs 2.9oz whilst a quality aluminium spinner of the same size weighs 6oz.




Propellers 28 For good power, stiffness and response, the all carbon Mejzlik 28”x10” prop is currently the preferred option for the DA-100. If your field is more noise sensitive then a 26”x12” or a 25”x12” 3-blade prop works very well but will be ever so slightly down on power




Many pilots in the US use the standard ‘dustbin’ silencers on their DA-100s however, in the much more noise sensitive UK where the fate of your flying field often lies in engine noise it would be nice to keep your DA-100 as quiet as possible whilst squeezing a little more power out of it if possible!! Fortunately, this can be achieved through the fitment of canister mufflers. Composite-ARF supply, as an option, a set of MTW headers and mufflers that will fit your 2.6m Yak taking all the headaches and guesswork out of the installation!!




FiberOptic Kill Switch


EDR-107 Photo This is certainly a one of the best items to fit to your Yak to ensure maximum safety for you and others.  Should your throttle servo or linkage fail for whatever reason this unit will allow you to kill the engine with a flick of a switch – no more flying round until you run out of fuel or chasing a dangerous run away model. The unit will also not allow the engine to start without a signal from the TX and also features a manual switch to kill the engine as yet another safety feature. Using fiber optic technology also mean no chance of RF interference. Very highly recommended!!


£55.00 Contact me for more information regarding the supply of this unit at
Ignition Battery


Can use a standard 4.8v - 6.0v (minimum of 1000mAh) receiver pack. £14.00
Fuel Tank


869690 We recommend a 32oz Dubro tank  - this will give a good 15min flight time (using a mixture of throttle settings) on a DA-100 with enough fuel spare for a few landing attempts!


Fuel Filler


This is a real luxury but for the ultimate in fuel fillers fit a 3W filler. Better than sticking a bolt in the end of your tank filling pipe!!!!


Wheels Kavan Very easy to gloss over but by using the Kavan 5” wheels you can save a huge amount of weight! They are incredibly light at 6oz per pair - compare this with 5” Sullivan wheels at 20oz per pair and you could easily be saving nigh on 1lb in weight!!! The only down side is they are not very durable on tarmac runways. If you want to ensure longevity on tarmac then I would suggest 5" Dubro wheels.


Tailwheel Assembly


You'll need something strong as your Yak will weigh approximately 26lbs yet light to avoid any balancing issues. Composite-ARF produce a nice optional tailwheel.






DO NOT try and cut corners here!! There really can only be one truly recommended servo for this model and that is the JR8511 servo. At 6v the power of these is simply incredible and you will never be left in doubt as to whether you’re asking too much of the servos – you won’t be! If you fly JR already then it’s no problem. If you fly Futaba it’s no problem either as the JR plug fits all Futaba sockets (just keep an eye on the + and -). You'll need 8 JR8511 servos and a servo of your choice for the throttle (don't skimp too much here either!).

If using the 8511 servos please make sure you ask me about the JR8511 servo disc problem or check the important announcement by clicking here.


JR8511 £67.00 each


Metal Servo Arms / Discs


The JR8511 servo is phenomenally powerful and needs a strong and reliable horn to transfer that power to the control surfaces. Composite-ARF do now not recommend the white plastic discs that come with this servo. Instead, either use a metal disc (to which you can still bolt the Comp-ARF servo arm) or a 1.5” all metal arm on its own. You'll need 6.


Arms approx £6.00 each






You will need a minimum of a 6 channel receiver to setup and fly the Yak successfully. It would be better to have 7 or 8 channels so as to allow you the safety option of a choke servo or fiberoptic ignition kill switch as well as the fun of a smoke system!! A PCM receiver is definitely a preferred option.




When using more than one servo per control surface (as you will on the ailerons and rudder) these units are great for 'matching' the servos to one another. This ensures that neither servo is fighting the other throughout the range of control surface movement. In turn this means there is no danger of drawing too much current from your RX packs due to servos fighting one another or indeed 'burning' out a servo that is fighting another. I admit that a geometrically perfect installation of horns, servos and arms will achieve this too but sometimes a little technology can help avoid hours of manual tweaking and tuning! You'll need 3.


£40.00 each
Servo Mounts


If you choose to not to use the built up plywood servo mounts supplied in the kit for the aileron and throttle servos, I recommend that you use JR servo mounts for your 8511 servos. You'll need 5.


£1.50 each
Extension Leads


Make sure you use good quality heavy duty leads. Try to avoid the ‘imitation’ leads as you may find that servos etc are a very tight fit into the sockets. However, rather than a secure fit this sometimes causes the pins in the plug to be pushed back and what feels like a ‘rock solid’ joint can actually sometimes be very weak. I have used the following heavy duty JR leads in my Yak: 


Inboard Ailerons:

Outboard Ailerons:

Rudder: Dependant upon your radio layout

Throttle: Dependant upon your radio layout

The aileron extension lead lengths are based on having a 'Matchbox' in each wing root which the aileron servos plug into.


Large scale models using 8 high power digital servos, long leads, multiple servos per surface as well as additional servos for throttle, smoke systems and chokes can put a huge load on your receiver possibly resulting in a failure.

To overcome this possibility and introduce a whole host of additional benefits such as dual RX pack capability, RF noise filters, servo pulse amplification, battery monitors and indicators and the ability to continue operating even if a servo fail, melts the cables and shorts use a PowerBus solution.

Myself and others (including many TOC pilots) have had great success with the PowerBox Professional and as a result this unit comes highly recommended.

This is an optional item. Otherwise, ensure you use a good quality PCM receiver.



More info on these powerbus solutions is available at





These are used if running a PowerBus solution. Heavy duty, ultra reliable and able to handle 20Amp loads they provide yet more "peace of mind" when it comes to the equipment guiding your new investment!

These are an optional item. Otherwise use good heavy duty switches.


£50.00 (pair)

More info on these powerbus switches is available at


RX Battery Packs


If using the recommended powerbus system you can run dual receiver packs for added security and reliability by plugging the packs directly into the powerbus. Until lithium packs become more mainstream I side with the heavier yet far more abusable nicad packs! General consensus on pack size ranges from 2 1900mAh packs up to 2 2400mAh packs.

If you choose to run the powerbus system or not I would definitely recommend running 5cell (6v) packs so as to attain maximum power from your servos.

I would also strongly recommend using a battery backer solution too, preferably one that utilises a 2 RX pack and 2 RX switch solution.


£25.00 each


AeroPoxy Glue Kit To ensure the ultimate bond when dealing with the composite materials used in these kits use Aeropoxy. Although quite expensive it gives good working time, will not run or sag and when dry gives a phenomenally strong bond.


Aluminium Cable Clips


  These little clips are superb for attaching servo cables etc in place almost anywhere in your model. £5.00  
Tie Wraps


  Invaluable for holding items in place securely. £5.00 Local HomeBase or B&Q store
Self Adhesive Foam Strips


  These foam strips are great for protecting items that you hold securely in place with tie-wraps from vibration etc £3.00  


* This column is for the UK market. For suppliers in your country please E-mail the Comp-ARF rep for your country/region.