RE: Skymaster L39 build
 

The pilot looks like a blue box F14 pilot, It's the same one I used google BBI F14 pilot.

Alex

RE: Skymaster L39 build
 

hey guys!
thank you !

Mark i only mean that with the p80se you cant after take off just pull up and go full vertical .

the jet requiers her full power after take off and i mean becarefull with the angle of climbing so you keep speed and not stall.

but once airborn and retracts are up i realy enjoy crousing around with the P80SE !


Stan about the retracts read on page 7 post 167..i also staffed two springs on the frond leg...i guess you could just change the main
weels with smaller diameter (like at skymaster hawk) but i dont think that would look good.

also about the elevator again:
if you have nose down and not level wing on take off

get ready for speed and to pull up litle hard to rotate on the mains(it depends how far c.g. is from main weel axles/i balance mine just after the wing tube on the aft side)

but once it rotate the elevator is VERY efective in the air so be gentle and dont pull any hover down on the deck



Alex i must ask about the cocpit pilot...im not the owner of this jet i only build it and i dont remember who the guy got it from[&o]

some of the guys have took videos so ill upload in the future when i got them in my hands...



take care guys!you love this jet more and more everytime you fly it!


(sorry for hte bad english)

RE: Skymaster L39 build
 

Alex and all that are using the Airpower EVSD-5u-pro multi function valve.

Did you use the restrictors that come with the valve hardware? I am seriously thinking of using all 7 restrictors as the gear and doors have a little to much energy.

I am wondering if I put them in will they slow the gear and doors down to much?

I am using two air tanks for the gear and doors and getting about 3-4 full cycles before it reach's the 50 pound automatic gear down mode.

Thanks,
Stan

RE: Skymaster L39 build
 

Stan,
I have sent you a separate email as well.
I am using the same valve, I used the restrictors and get the same result. The doors open extremely fast and hard, but the wheels are quite good,
I am using the 3 second delay for the gear. I also get 3 to 4 up downs in fact I will set 3 as safest.

However I am struggling with the brake mode, so far I haven't managed to make it work, and it looks like I will have to reset
the PRO and start again. I also have to check the failsafe for the gear.

Regards
Ross

RE: Skymaster L39 build
 

Hi Ross,

Looks like I will be putting the restrictors in. It would be nice if we could control the air flow electronically as opposed to using restrictors. The unit does about everything else.

This unit will spoil you.

Thanks,
Stan

RE: Skymaster L39 build
 

Hi Stan, I used TamJet restrictors as they restrict the flow a bit more than the airpower ones, works well. There's some better instructions on Airpowers website, I found the instructions that come with the unit are poorly translated.

Cheers, Alex

RE: Skymaster L39 build
 

Hi Alex,

Thanks for the tip on Tams restrictors. I have been using the instructions off the web site. You are correct they are a lot better.

I seem to remember you saying in an earlier post that you also used two air tanks for your doors and gear. How many complete cycles are you able to get before you reach your 50 lb limit to deploy the gear?

I am getting about 3-4 cycles if I fill both tanks to around 120 lbs of preasure.

How is your new build coming along?

Thanks,
Stan

RE: Skymaster L39 build
 

http://www.rcuniverse.com/forum/m_9548124/tm.htm


[youtube]http://www.youtube.com/watch?v=uARMUHOSryE&feature=channel[/youtube]

RE: Skymaster L39 build
 

Nice motion you have on those retracts George.

Hi Stan, yes I've used two airtanks for the gear it gives me 6 cycles with about 65psi in reserve, I think the key is volume rather than pressure, I always use 100 psi as my max pressure which works very well with two tanks. I double up on tanks for all my builds now. I'll take some pictures of my air set up for you.

The Hawk is nearly finished, just wiring the radio in then its on to weathering the airframe, should be with the customer in a week and flying within 2.

Cheers, Alex

RE: Skymaster L39 build
 

i agree with Alex!

bigger volume holds same presure longer

i use 2 tanks or more for retracts and one for brakes

dont forget to take a vid of the hawk Alex![8D]

RE: Skymaster L39 build
 

Hi Alex,

I too have two air tanks for my gear and doors. When I set my preasure to approx 120 lbs, there are no leaks. I can only get 3 complete cycles till it reaches 50 lbs.
I am using the restrictors on all 5 of the outputs. I have not used the restricters yet on the input side. Are any of you using the restrictors on the input side? I am wondering if that will make a difference.

Another question....When the gear is up or down the doors are closed. How are you getting to the screw which holds the wing on with the gear door closed to remove your wing?

Thanks, Stan

RE: Skymaster L39 build
 

on the photo below you can see a Robart Air-Line Quick-Disconnect(white)

this is (T) on my retract/doors air tanks

i disconect that at the end of the day to releafe presure and to be able to open main doors to get the screws

RE: Skymaster L39 build
 

Hi George,

Good idea on the release of air from the tanks. I hadn't thought of that.

Thanks,
Stan

RE: Skymaster L39 build
 

Hey Stan!

hows your building doing?

..i use one robart restrictor closest to the cylinder so it will stop snaping on down and couse promblems

RE: Skymaster L39 build
 

Hi George,

I need to order some robart restrictors for the down cycle. Good idea.

I am very close to finishing up. Unfortunatly I will be tied up for the next several weeks and any flying will be on hold.

Thanks,
Stan

RE: Skymaster L39 build
 

Hi Stan, I did the same as George with the quick release. Do you know what size tanks your using?

I'll try and take a vid if I'm there for its maiden, I'm far from a natural cinematographer the last video I took made me feel sea sick when I watched it back [:o]

Cheers, Alex

RE: Skymaster L39 build
 

Hi Alex,

I am using the same size tanks that came with the kit. I bought a 3rd tank from BVM same size as the other two. I have two hooked together for the gear and doors and the third for the brakes.

Stan

RE: Skymaster L39 build
 

L39 CG
Just a question on the CG position for the L39.
I am using a Jetcat 120 and I have 4 batteries to power everything.
1 large 3cell A123 for the receiver (battery 1) on one side of the nose wheel an 7.2volt NiMH pack (battery 2) on the other side of
the nosewheel, and immediately behind the former carrying the nosewheel 2 more A123 batteries, one for the ECU and one for lights.

With all this weight up front I expected to have the cg near correct, but on an initial quick check it looks like I am still a bit
behind the 125mm that Skymaster suggest.
Have others had a weight problem and if so how much lead have you had to put in, and where has flying shown
is the best spot for the CG?

By the way my checks were done with empty tanks.

Regards to all
Ross

RE: Skymaster L39 build
 

HELP............ ok, gear doors. I can not get them to work right. meaning I can not get the geometry set up.


what horns did you guys use and what size rams did you use? the rams I have are 1-1/2 throws maybe 2 inch would be better? max throw, if I set the doors flush with the fuse, I can not get them open enough to get the wheels in or out.

amost at the point as where I am thinking of leaving the gear doors off, although, I did get the nose gear door working without any problems....



Mark

RE: Skymaster L39 build
 

gear doors are always a pain........

I'll take plenty of photos this afternoon for you, I did change my rams to UP not sure of the throw. again I'll find out...

Alex

RE: Skymaster L39 build
 

In the mean time have a look at post 10 should explain things a little.

Alex

RE: Skymaster L39 build
 

Alex, did your come installed with the kit? and it sure looks like the shaft is a bit longer then what I have, like i said before, my throws on the rams are at 1-1/2 inches. if they were I think 1-3/4 or even 2 inches I would be ok.....

Mark

RE: Skymaster L39 build
 

Flap servos.
Has any had problems with what sounds like the flap servos under load, when the flap is flush with the top
surface of the wing. In other words the normal flying position.

Both my flap servos start to whine when the flap is closing the last few millimeters (fractions of an inch).
If I set the resting position of the flap, that is part way towards the launch posotion, the noise stops.

It sounds like the flaps are under load, trying to hold the flaps in their normal position,

Ideas please, as the noise is quite loud and distracting.

Thanks
Ross

ps I have tried to lots of servos Hitec 5645 and the 7965 both have the same problem.

RE: Skymaster L39 build
 

Ross, I used ball links on the ends, I do not have any noise on the flaps. I am useing the JR 9303 radio, and I have the speed on the flaps turned down, takes about 2 seconds to get to full flaps and the same to come back up. love that function in that radio.
and I can get my flaps to drop where the bottom of the flaps are 90 degrees to the fuse, might be to much flap, but we will see.

Mark

RE: Skymaster L39 build
 

use a current measuring device to setup your servos, as you may be stalling them. Sometime a very small adjustment leads to significant decrease in current use.