kemp83

Hi guys! Ihave just bought a PHOENIXYAK54 60. Check the link:http://www.phoenixmodel.com/Default....CatId=15&id=28
I want to build this aeroplane to fly both 3D and sport-scale and at the same time land easily!
I am trying to decide which engine to install on it:
1. Saito FA 125
2. DLE-20cc
3. OS 120 AX

Here aretwo nice videos with 1st and 3rd engine installed on this plane:
http://www.youtube.com/watch?v=kB5S1FoPDFw
http://www.youtube.com/watch?v=0yPkTejsRX8

I already know Saito is double the price of the other two but weights around 200gr less. I also know thatnormal gasoline, DLEburns, is much cheaper than nitro-but then againI only fly once per week, 3-4 flights, in best case scenario.

So which one suits me best?
Which vibrates less? Saito or DLE?
Which burns more fuel?
Which is more responsive?
Which is easier to break-in, set up and run?
Will DLEbe ok running with 95 octane? Manual indicates 87-93...

Looking forward to your comments...

kemp83

I have just found this comment in users reviews: "Just be sure that you have a radio that has a throttle curve because this engine makes so much power from the start that you need a fine control on the low end".
Will Futaba 6EX be ok for this aspect?

ameyam

I am currently fitting the Phoenix Extra 60 (which is essentially the same airplane with a Extra type cowl) with a DLE20. A fellow flier has that Yak witha 120ax and he just loves it. He has a 18x6 prop and it hovers at 40%. I am sure the DLE20 will do the same and it weighs similarly. A Saito will be slightly lower power.

Few things you must do with the airplane for either the DLE20 or 120AX

1) Replace the stock blue mount. Its too soft. For the DLE use GP 120-180 adjustable mount and the 120 use the 90-120 mount.

2) Fibreglass the firewall and LG block. The firewall is a bit weakly attached to the fuse. You need to cut off some of the ply from the underside to get to the back of the firewall, then add in tristock wherever it can be installed. Also add tristock to the LG block

3) Use nylock nuts behing the blind nuts for both the LG and firewall. Its a pain to get to both but worth it

4) The stock LG is soft and two piece. If you land hard or deadstick it will just break the LG Block in half. Get a one piece LG from the Extra of the same size or get CF LG(20cc) from Hobbyking. If you put in the DLE you will need it to lose weight

5) Add in tristock everywhere in the fuse for additional strength

Make a note- the airplane flies very well with power. In a deadstick there will be lot of tipstalling. Be aware of this if you are going to harrier or if the engine is not fully tuned

Ameyam

kemp83

Thanks Ameyam! Thats very useful! Let me know when you fly your extra about the results.

kemp83

Hi Ameyam!
Have you flown your Phoenix EXTRA 60? What are your comments?
I am waiting my DLE20 in a few days and I am wondering what batteries I should use-will it be overweighted if I use a 6V NIMH for the receiver and a 4.2V NIMH for the ignition?
What did you use?
What about the this comment in users reviews I have found for the DLE20:"Just be sure that you have a radio that has a throttle curve because this engine makes so much power from the start that you need a fine control on the low end". Did you make any settings on the throttle curve?If yes, will Futaba 6EX be ok for this aspect?

Thanks!!!

ameyam

you are on the right track in that you are asking all the right questions.

I initialy thought that the Phoenix Extra 60 and the Yak 60 were the same airplane. But when I had a chance to place the two nest to each other, I noticed that the Yak is a bigger airplane- not in terms of span, interms of overall size.

Now, my Extra is not exactly stock- I learnt from all the mistakes my friend made on his Yak and took care of the same in the Extra build

Firstly, it will be over weight. Even though the DLE20 and the OS120AX is the same weight, you will have to use a 120-180 adjustable mount for the DLE20 (I used the one from GP). I moved the engine as fas back as possible- the carb was just so far from the mount base that you can rotate the choke lever. Then I used 3.25" foam wheels and a 2.5" GP nylon spinner with aluminium backplate (and radical surgery with a dremel) to lighten the weight. Initially I flew without the cowl but later I installed the cowl. I used a 6V NiMH on the ignition and a 1300mAh LiFe on the RX. The LiFe is strapped to the former at the wing TE along with the RX and the Ignition battery is packed in the space just adead of the wing tube. The ignition module is strapped to the ply in the muffler tunnel. Of course, I used a NGK spark plug. I Though the stock firewall is thick enough, I fibreglassed it from the outside and epoxy painted it from inside for peace of mind. I also epoxy painted the inside of the fuse and applied tristock wherever I could reach- inside of firewall, all bulkheads, all sides of the LG block, TE end of fuse hatch, inside of tail (before it is assembled) etc. I also fibreglassed the fuse block and used nylock nuts everywhere I could reach. I alse used scrap ply doublers in key areas. Rest is stock (which, I admit, isint much)

With the bare engine, without spinner it weighs 3.85Kg which is atleast 300g overweight and the CG is 10mm forward of where it is suggested.

With the cowl and spinner its close to 4kg and 20mm forward CG. I used 7 x 7g sedmented weights (taped to the tail) just ahead of the tilwheel. Its still nose heavy and I cant hover (yet)

Depending on how you set your throttle, you will have to add the throttle curve or atleast some expo. I had a problem in that I was cruising at 20% power and landing was difficult as one click was enough to send it soaring. Now with 50% expo, its much easier to land. You have to keep some speed at landing though.

I am using a 9CAP and a 8FG is in the box. My 6EX is completely out of use now. It probably has expo but not throttle curve, you need to check the manual. Also, it will require you to use a y-connector for both ailerons and elevators, so the deflections on them will not be the same and it will cause snapping. That is however, a characteristics of the airplane though. I suggest you get a servo mixer such as the MSA 10 for the elevators atleast to remove the snap

Mine is fairly sturdy. This weekend, I had a mid-air with another airplane. It was too far up to see what hit but the other one was minced up (it was a foamy). Mine doesnt seem to have any damage. The stock LG is very soft and has to be straightened every weekend. I haven flown the airplane much though

Now for all that effort, it has gobs of power. Its all giggles to fly even for the club instructor. It doesnt tip stall (balance it laterally) but flat stalls (I have already sealed the hinge gap with tape). You can manage the non-linear throttle curve through programming.

To reduce weight you can, firstly not do all the strengthening I did and secondly, use a LiFe on the ignition (that will save 80g, remember to use diodes) and get yourself a CF gear (if you are absolutely secure with landing it comfortably. Mine is ready for installation after I know the airplane better. It will save another 80g). Thats about it

Ameyam

overbored77

My Feedback: (11)

Kemp, for batteries you can use a single 3000 MAH life with a IBEF. this will give you more than enough power for a a few flights
and you will only need 1 battery for the plane, I am installing this setup on my 1.20 sized Phoenix edge 540 with a DLE 20. I recently
put a 3800 mah LIFE pack on my 40cc plane and with the IBEF I was able to remove my (3) 1500 mah nicad from the plane.
my total weight savings was 1/2 pound.

raydar

If you go to the gas forum and read the stickys at the top it will show how to set up your throttle servo arms so that expo is not required for goood low end rpm control. My first gasser was set up wrong and it was a dog at low rpm till I realised my mistake.

kemp83

Thanks guys! Great stuff!

kemp83

overbored77 ,

billd76

My Feedback: (3)

Here you go, http://www.valleyviewrc.com/estore/r...-with-bec.html I use these for all my gas engine. I use a 123 2300 MaH life battery with this kill switch. The 2300 Life will fly my plane all day long. Helps save some weight as well.

overbored77

My Feedback: (11)

IBEF, is an ignition battery elimination filter. here is link to one http://www.bphobbies.com/view.asp?id...4&pid=F2143792 As for
checking batteries there is a special load meter for LIFE batteries, I didn't buy it, I just installed the LIFE batts in my plane so I will
go out and fly 2 10min flights and then recharge to see how much I used. this will give me an indication how many MAH I use per flight
and how often I need to recharge. my way of thinking is that if the math says i can do 6
10 minute flights before having to recharge I will recharge after 4 to be on the safe side.

kemp83

Thank you guys! All these are really helpfull

andrew7771

My Feedback: (1)

I just finish assembling my Yak 54 from Phoenix, with a DLE 20 cc engine. I used the CG measurements they suggest on the book. The plane it way tail heavy. I moved the battery ignition and the ignition to the sides of the firewall to make it nose heavy. still it is tail heavy. I moved the receiver battery and still didn't work. Can you tell me your experience with the CG of you plane? did it come right? I am just afraid to fly it if it is not well balanced.

Thank you for your help.
Andres

ahicks

My Feedback: (2)

That plane will fly fine with the CG near the front of the wing tube.