Official Freewing 80mm EDF L-39 Albatros Thread

[Joehockey]

Thanks for the help guys , I ordered the FMS upgrade from RC Castle , so lets hope 2021 brings grass opp success

[Evan D]

It's about a mm all around. Instead of taking and sanding away a mm I sometimes just take my thumb and compress the foam a bit.

[xviper]

Here's a take-off from grass, Wemotec 80mm Midi Fan Evo, HET 700-65-1865, 120A ESC, 8s 4500mAh

Yup, mine with the FMS EDF takes off about 50% longer distance, still very short.

[xviper]

Thanks I will look into the upgrade considering I making another $100 investment in the new fueslage. The Club Pres is very experienced, I think everyone flying electric jets at our field, the model really took him by surprise.

Please note: The FMS fan unit doesn't mount perfectly flush. It' a couple mm larger in outer diameter, so you either have to shave off a little foam around the fan or you just mount it and deal with the small ridge due to the fan hatch not sitting flush. Since that area is red, I didn't bother with shaving foam. I just covered the seam with red tap. If that bothers you, then you'll need to do some shaving, but since you're dealing with a new fuse, it shouldn't be too much of an ordeal to work with it before everything else goes into it.

[Radar-Guy]

Here's a take-off from grass, Wemotec 80mm Midi Fan Evo, HET 700-65-1865, 120A ESC, 8s 4500mAh

[Joehockey]

Thanks I will look into the upgrade considering I making another $100 investment in the new fueslage. The Club Pres is very experienced, I think everyone flying electric jets at our field, the model really took him by surprise.

[xviper]

I do have the option of a lighter pack to test but obviously less flight time.
Yes, it's just for "testing" to see if weight is a factor. If it is, then buy lighter packs that are still 5000mah. Most non-graphene LiPos are 150g+ less weight than HobbyKing Graphenes.


As far as flaps, 1/2 flaps was the reason for an early lift after two attempts. The president of our club is by far the most experienced pilot, having flown everything from 45lb birds to turbines.
I change out another pack and was determine to do my best to forces it into the air but attempt to keep control. Unfortunately it did what I wanted, lifted off but without proper airspeed, and my best efforts to prevent a stall failed.
This is where the "experienced" pilot should have known what to do. As soon as the plane leaves the ground, you must immediately level out and stop it from continuing to climb. This allows for more airspeed very quickly before you try to climb. I am surprised that your club president was not doing this.


Viper do you have a Inrunner you suggest ?
Yes, I have the FMS 80mm 2100kv inrunner in mine. I put that in after I had flown it stock for about 1/2 a season. I did it not to get off the ground any sooner but to get a little more speed in the air. It did shorten the take off run by about 50 feet. You can buy it via your local hobby shop from Horizon Hobby.

[Joehockey]

All good points and I appreciate the feedback. I do have the option of a lighter pack to test but obviously less flight time.
As far as flaps, 1/2 flaps was the reason for an early lift after two attempts. The president of our club is by far the most experienced pilot, having flown everything from 45lb birds to turbines.
I gave him a shot with a fresh lipo after two attempts on my own. He did everything possible to take off with 25% flaps, good clean straight run and this thing hugged the ground like a baby hugging his mommy on the first day of school !
I change out another pack and was determine to do my best to forces it into the air but attempt to keep control. Unfortunately it did what I wanted, lifted off but without proper airspeed, and my best efforts to prevent a stall failed.
The fuselage is repairable but at the cost of adding weight to a model that should not gain an oz in my opinion.
Based on my investment I may take your suggestion to increase the power via the ducted fan.
Viper do you have a Inrunner you suggest ?

[xviper]

I am on my second fuselage and looking for some expert advice. I fly with Graphene 6 cell 5000 packs and they are heavy. I know that CG is CG so it’s up to me to make sure I get it correct. Considering I have to disassemble the model to replace the fuselage I am considering moving some things around.
Can anyone show or post a pic of what they feel is the ideal CG on this model ? Jets really really struggle at our field to take off, while its well maintained, jets are Legendary problems at my field. So , CG is not only critical for proper flight but its critical in relationship to a successful take off .

Most of us are forced to rush lift off in order to keep from running out of runway ( not good ) , also depending on the wind, one end of the runway is a cliff !

I am not sure that the Graphenes are simply too heavy for this bird and really inhibiting lift off but its been a crap shoot on take off runs !

It is well known that HobbyKing Graphene (or any other Graphene) batteries are much heavier than other non-graphene type of battery. I've always bought Graphenes with that in mind. IE, if I'm after a 2200, I buy 1800; if I'm after a 3500, I buy 3000, etc. The 5000mah Graphene, 6s is more like a 5600 to 6000 mah non-graphene. However, I doubt that an extra 150g to 200g on THIS plane is going to make a huge difference in take off distance. Try a lighter battery just to see. If it does make a difference, then an option may be to put in a higher thrust EDF (like an inrunner from FMS if it doesn't have one already) and always use a high "C" rated battery.
As you say, CG is CG and I've stuck with the manual recommended CG for GeoTex, smooth grass and rough grass and the longest this plane takes to left off is about 200 to 250 feet on very plush, unmowed grass. Do you use 1/2 flaps for take off? This can help greatly for this plane. Do you use high rates on the ELE for better rotation? Sure, you could move the balance point further back to get it to rotate sooner, but then, you may be dealing with a tail heavier plane that becomes twitchy in the air. The old adage "A nose heavy plane will fly. A tail heavy plane may fly only once." may be true for this plane.

[Joehockey]

I am on my second fuselage and looking for some expert advice. I fly with Graphene 6 cell 5000 packs and they are heavy. I know that CG is CG so it’s up to me to make sure I get it correct. Considering I have to disassemble the model to replace the fuselage I am considering moving some things around.
Can anyone show or post a pic of what they feel is the ideal CG on this model ? Jets really really struggle at our field to take off, while its well maintained, jets are Legendary problems at my field. So , CG is not only critical for proper flight but its critical in relationship to a successful take off .

Most of us are forced to rush lift off in order to keep from running out of runway ( not good ) , also depending on the wind, one end of the runway is a cliff !

I am not sure that the Graphenes are simply too heavy for this bird and really inhibiting lift off but its been a crap shoot on take off runs !

[pilot2fly]

Hi there, does anyone know the color code for the red on the red/white/blue version of the L-39? I'm trying to find a matching or almost matching spray paint. I want to paint the fuel tanks red and repaint the blue part of the wings red.

[steven gubala]

Thanks Monty500, will check into it

[Monty500]

Is there anyone else out there that uses a AR637T receiver, that could help me out with the programming, on L-39. Thanks any help would be appreciated.{

Hi Steven,

Have you seen this series by Horizon on how to setup the 637? Not an answer to your question regarding L-39 setup specifically but hope it helps?

AR637T & AR630 AS3X Setup Series #1 - Introduction - YouTube

[Aerobatic Addict]

Is there a advantage or disadvantage to not installing the pylons if you are not going to fly with the optional attachments. I think it would be a cleaner airframe look without them but they may help add some side area in knife edge sort of like the pieces that are in the middle of the Avanti wing but only on the bottom.

[steven gubala]

Is there anyone else out there that uses a AR637T receiver, that could help me out with the programming, on L-39. Thanks any help would be appreciated.{

[Monty500]

My camo L-39 finally arrived with the trip from Hong Kong taking just under two months by sea freight (air freight from China to NZ is still unavailable at the moment due to the current microbiology situation). I will be fitting additional dorsal and belly strobes and RC Geeks centerburner and will use an AR7350 receiver.

Any advice regarding dual rates, flap mixes, cg and gain setting for the AS3X receiver would be welcome.

Seasons compliments to all and stay safe during the festive season.
Mike

[Radar-Guy]

It was just replaced with the HP version with the newest inrunner.

Oh, thanks!

[JamesonC]

One of the best flying jets...

It was just replaced with the HP version with the newest inrunner.

https://www.motionrc.com/collections/rc-jets/products/freewing-l-39-albatros-high-performance-9b-80mm-edf-jet-pnp

[Radar-Guy]

One of the best flying jets...

[Guipedroso]

Its not old, is a perfect plane :)
They are not on sale, but you can order the job in any sort of online printing service... there are plenty out there...
Still have to paint it, is a bit of a pain...