Pilot RC 26%/30cc Yak 54 setup thread
 

As the title says, this is a "setup" thread for my now maidened Pilot RC Yak 54. Not very much info on this plane out there so I figured I would post it here to help get the word out.

The maiden was fairly eventful...the set screw on the throttle arm on the carb came loose so I only had partial control over the throttle...it was turning fast enough to fly but way too fast to land. Had to kill the engine using my IBE (will explain later) and land deadstick. Other than that, it flies great....crisp snaps that start and stop on command...all kinds of power on the uplines and it floats really well on final. Seems to be a good solid airframe to start the tuning process.

It is one of the latest offerings from pilot in the 73" range that is designed around the DL30 gas engine. I paid particularly close attention to the weight of this bird...Pilot claims an AUW of 10.5lbs...my goal was 10 lbs dry. So here it goes....

Re: Pilot RC 26%/30cc Yak 54 setup thread
 

few more. The plane in the last picture is a 40% Extra 260 so it gives you an idea of the size of this plane. It easily fits in the back of my station wagon yet it is big enough that if feels "big" in the air.

Re: Pilot RC 26%/30cc Yak 54 setup thread
 

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Re: Pilot RC 26%/30cc Yak 54 setup thread
 

To give you an idea of how compact the DL30 is, I compared it to a Jett 60LX which is very close in dimensions to a OS 46. DL managed to pack a lot of power in to a small engine....upwards of 19 lbs of static thrust with a 19 x 8.....or so they say.

Re: Pilot RC 26%/30cc Yak 54 setup thread
 

As I mentioned earlier, my goal was go get the all up dry weight to 10lbs or less. So, here is my setup:

Hitec 5955's on all flight surfaces using the stock Hitec arms.
HS 81 for the the throttle
Rhino 20C 2150mah lipo for the ignition and the servos
AR7000 receiver
Flightpower 8amp failsafe regulator
Standard Futaba switch (grabbed it out of the junk pile...:cheers:)
Wike RC Ignition Battery Eliminator
Lightweight 3" Hobby City foam wheels
MPI 3/16 Titanium axles
12oz juice bottle for the fuel tank in conjunction with the Sullivan aluminum stopper kit
Hangar 9 fuel dot
JXF 19 x 8 prop
Used all of the supplied hardware except the servo control horns.

This is your typical ARF so their's nothing special about what goes where and such but like I mentioned, I wanted to keep it as light as possible (short of tearing the airframe apart). Here are some of the weights of the bare airframe components before lightening:

bare fuselage - 28.3oz

bare hatch - 7.6oz

left horizontal stab - 2.59oz

right horizontal stab - 2.7oz

rudder - 2.32oz

left wing - 15.2oz

right wing - 13.0oz (big difference in the 2 wings - :yuk: had to add 1.5oz to the right wing in order to achieve a proper lateral balance)

carbon landing gear - 3.14oz

carbon wing tube - 2.8oz

carbon tail wheel assembly - .99oz

carbon tail tube - 0.65oz

stock axles - 0.76oz each with collars

stock wheels - 1.44oz each

stock fuel tank - 3.15oz

wheel pants - 1.67oz each

spinner - 1.85oz

cowl (uncut) - 8.2oz

As an aside, I measured the complete DL30 (ignition, muffler, standoffs, bolts, etc) and it came out to 41oz even.

Re: Pilot RC 26%/30cc Yak 54 setup thread
 

The first part of the diet consisted of an overweight fuselage and a dremel with a sanding drum. After about 2 hours work, I managed to drop the fuselage from 28.3oz to 25.8 oz...a savings of 2.5oz. Doesn't sound like much but that's about 9% of the total weight....that is fairly significant in my books. You can see in the pictures where i dremeled out the motorbox sides, the firewall, motorbox bottom, the F1 former, etc. It's hard to tell but i did take a bit out of the landing gear plate and around the top of the fuselage where the hatch sits.

Next was the hatch. The stock weight of the hatch was 7.6oz. After removing all of the foam and plywood from the bottom where the pilot bust normally would mount, I managed to bring it down to a final weight of 6.28oz...that's a savings of 1.3oz....nearly 17%.

Their wasn't really much I could do with the wings so I just left them stock. Same goes for the rudder and the stabs.

One thing I did do that took a fair bit of time was to cut off all of the bolts that were too long. The cowl bolts were about 12mm too long so after doing this to all the bolts, the savings start to add up. I didn't bother weighing the bolts before and after being cut.

Re: Pilot RC 26%/30cc Yak 54 setup thread
 

The bone stock tailwheel assembly came in at 0.99oz. After some cutting and creative MacGyvering, I managed to get it down to .75oz. Instead of using 2 wheel collars (one on each side of the tailwheel), I opted to toss the wheel collars and solder a washer onto the axle. This also allowed me to cut off the remaining axle to further reduce the weight. The CF bracket came with 3 screw holes on the top however I opted to only use 2 of the holes, therefore I was able to cut off about 1/2" of the bracket. The rubber tailwheel comes in at 5.6 grams but I have some 1.5 gram tailwheels in the mail that I am going to try out from Hobby City. The tailwheel currently sits at 0.75oz..a savings of 0.25oz or 25%.

The stock steel axles, while plenty strong, were a bit on the porky side at 0.76oz each (with both wheel collars). After looking around for a lighter axle, I came across the MPI titanium alloy axles. For 16$ they were worth a shot. They claim they are half the weight of stock 3/16 axles and they were right...the titanium axles came in at 0.36oz....that's a savings of 0.4 oz per axle x 2 = 0.8oz or 53%. Rather than use wheel collars, they have grooves cut around the diameter of the axle that use a C clip...interesting. 2 flights and some high speed taxiing and no departed wheels yet.

Re: Pilot RC 26%/30cc Yak 54 setup thread
 

The stock 3" wheels are of very high quality with decent rubber and a nice machined aluminum hub.....however they had to go as they came in at 1.44oz each. Bolt on some 3" hobby city foam specials (.51oz each) and you come up with a total savings of 1.86oz or 76%.....and they were only 2$ each!! :cheers:

I opted to not bother with the wheel pants although they do seem like a very well finished, rugged pant. They came in at 1.67oz each with no blind nuts of mounting screws.....savings of 3.34oz.

Same goes for the stock carbon spinner....savings of 1.85oz.

Next...the fuel tank. After weighing the stock tank that came with the kit and reading on Flying Giants about some of the guys using pop bottle as light weight fuel tanks, I decided to give it a try. So, after fiding an ideal tank at my local sobey's, here is what I came up with. (see above pictures) It is 12oz juice bottle that is perfect as it is square in shape and very light. I also opted to go with the Sullivan HD aluminum stopper as I wanted to make sure this thing work work out ok...that seems to be the popular setup among the guys on the other boards. The stock tank, ready to go came in at a hefty 3.15oz however my custom juice bottle tank came in at 1.75oz....that's a savings of 1.4oz or 44%. Also, the bare bones stock tank came at 1.94oz while the bare bones juice bottle with the lid came in at 0.99oz....basically half the weight. :yuk: Kinda makes me wonder why the ARF manufacturer's continue to supply the "traditional" rc type fuel tank.

Re: Pilot RC 26%/30cc Yak 54 setup thread
 

Next on the chopping block was the battery. I used a 20C 2150mah Rhino 2S from Hobby City. It cost 8$ so you can't really go wrong with that. The stock battery came with 10 gauge wire and a balancing tab. I opted to lose the balancing tab and the 10 gauge wire in favor of some lighter wire to see how much weight I could drop. The stock battery weight was 4.12oz and the modified battery weight came in at 3.45oz...that's a savings of 0.67oz or 16%.

Even the switch was chosen to be as light as possible. I also chose to use a failsafe Flightpower regulator to power my servos and receiver and IBE. The Flightpower reg was chosen becuase if it failsafe so if the switch fails (goes open) then the reg will default to "on". Usually I use atleast one JR HD switch however at 1oz each, the JR switches aern't the lightest. The stock Futaba switch came in at 0.385oz however after modifying the switch to work with the failsafe plug of the regualtor, the end result was a switch with an auw of 0.25oz....that's a savings of not a whole lot...but 0.135oz is better than nothing. If compared to a HD switch, the savings are even more evident.

Pilot supplies a seperate throttle servo mount made out of lite ply that weighs 0.25oz. The typical standard servo tips the scales at 1.5oz. Rather than use the standard servo and mount, I opted to build my own balsa servo mount on the top of the motorbox and use a HS 81 for the throttle. The HS81 comes in at .58oz. That's a savings of 1.17oz over a typical stock setup. Every ounce counts.

Re: Pilot RC 26%/30cc Yak 54 setup thread
 

Pilot supplies a nice offset rudder servo control horn that seems very robust and solid. I had an offset SWB aluminum 3" arm lying around so I figured i would weigh the 2 and see how they compare. Using the Hitec HD round servo horn and the supplied rudder servo horn, they came up to .56 oz :yuk: . The SWB aluminum arm came out at 0.16oz :p. Needless to say, I went with the aluminum arm. That's a savings of 0.4oz or 71% over the typical stock setup. I also opted to use the Hitec HD servo arms on all the other surfaces as these too were much lighter than the supplied servo control arms for the ailerons and elevators. (didn't measure those weights so i'll leave them out)

Finally, the typical ignition power setup consists of a seperate battery, seperate regulator and an optical kill or some sort of cutoff device. What I decided to do was use this little gizmo from Troy Built...it's called the Ignition Battery Eliminator (See last picture). Basically, it draws power from a spare slot on your receiver to power your ignition however at the same time, it acts as an electronic kill so that you can cut the power to the ignition via a switch on your transmitter. The IBE has filters to stop "most" of the interference from the ignition from getting back into receiver. While not as good as an optical kill, it does eliminate the need for the above mentioned items. Range checks fine and works exactly as it should. The typical ignition powersetup comes in around 5oz. The IBE comes in at .075oz. That's a savings of 4.25oz and it costs less than a ignition reg, optical kill and battery. The downfall is that I will probably only get 3 flights or so before I will have to either recharge my battery or swap it for a fresh battery. Also, the optical kill is a better method of eliminating interference from the ignition getting back to the receiver. So far, so good.