Official Freewing 80mm EDF L-39 Albatros Thread

[T-CAT]

Nice writeup T-Cat. I concur on the aux inlet cover. My testing showed a dramatic reduction in performance with the inlet covered.
https://www.hobbysquawk.com/forum/rc...190#post156190

As far as the battery tray goes, my wingman flew the Admiral 5000, Admiral 4500, and Predator 4000 in his L-39 yesterday. The 4000 was almost all the way up at the fwd bulkhead. But she flew fine.

Our jet group is waiting on the third member to get his L-39 this week. Then we will make a decision as to whether we re-paint them. I imagine an airbrush is in my future.
We have made the decision to not install or, in my case, remove the pylons. The drop tanks do look nice. But they slow her just a little.

Yesterday we got in 6 flights on the L-39. I'm around 20 flights now. The fan appears clean. I guess the bird sits high enough off the ground that it doesn't "hoover up" as much stuff as some others.

Thanks Sea Viper. Great write up as well on you’re experience with closing the Aux. inlet. You saw the same exact thing. The difference definitely wasn’t tiny, it was drastic. Lesson learned, and at least it was an easy experiment and easy to get the plane back in flying shape.

One thing about the pylons installation, i found they work great for setting the plane down without the gear extended either for transportation or when arriving or packing up while it’s on the ground or table at the field. It lifts the plane up just enough to allow the body of the plane not to touch. Who knows, maybe it will also help save some of the planes surfaces like the belly or wing linkages during an emergency gear up landing, assuming they stay on. Those were the only reasons I installed the pylons since I have no desire to fly with the tanks on.

[Alpha]

Great write-up, T-Cat and Seaviper, I appreciate your sharing your experiences with the group!

Indeed, the L-39 is about as sport jet-ish as we could make a scale jet in terms of its overall handling and flight envelope. Those of us who remember the old tip-stall-happy L-39s from Sapac and HTG can attest that short wing isn't always friendly, but I think we've tamed it well on Freewing's 80mm L-39. My goal is to make appealing designs fly well. A long bodied, short winged, mid-tailed aircraft is just one step along the path to getting y'all confident of operating that 4x80mm Concorde. LOL

T-Cat, you also hit on something that others have asked about and is worth repeating. The reason why Freewing's low wing aircraft almost always incorporate a glued on pylon is to use that pylon as a standoff to keep the majority of the model off the ground. The F-86, Mirage, A-4, F-4 and L-39 are all good examples of this philosophy. Even if there are other pylons on the model that are removable (A-4 and F-4), at least one pair of pylons is always glued on. Mid-wing models like the F-16 and F-14 use completely removable pylons, since there's no opportunity to do double duty as a standoff. The only recent example of a low wing model without any glued on pylons is the A-10, because its main wheels and nacelles double as a built-in feature to keep the main fuselage off the ground. Incidentally, this is also what the real A-10's designers had in mind --minimal damage during a wheels up landing.

[T-CAT]

Great write-up, T-Cat and Seaviper, I appreciate your sharing your experiences with the group!

Indeed, the L-39 is about as sport jet-ish as we could make a scale jet in terms of its overall handling and flight envelope. Those of us who remember the old tip-stall-happy L-39s from Sapac and HTG can attest that short wing isn't always friendly, but I think we've tamed it well on Freewing's 80mm L-39. My goal is to make appealing designs fly well. A long bodied, short winged, mid-tailed aircraft is just one step along the path to getting y'all confident of operating that 4x80mm Concorde. LOL

T-Cat, you also hit on something that others have asked about and is worth repeating. The reason why Freewing's low wing aircraft almost always incorporate a glued on pylon is to use that pylon as a standoff to keep the majority of the model off the ground. The F-86, Mirage, A-4, F-4 and L-39 are all good examples of this philosophy. Even if there are other pylons on the model that are removable (A-4 and F-4), at least one pair of pylons is always glued on. Mid-wing models like the F-16 and F-14 use completely removable pylons, since there's no opportunity to do double duty as a standoff. The only recent example of a low wing model without any glued on pylons is the A-10, because its main wheels and nacelles double as a built-in feature to keep the main fuselage off the ground. Incidentally, this is also what the real A-10's designers had in mind --minimal damage during a wheels up landing.

Thanks Alpha. You can most definitely tell the L-39 was designed with ease of flight in mind by taking out much of the oddities that some L-39 models in the past had exhibited. It’s a docile and versatile aircraft that people can feel comfortable with very soon after its initial flight or on the actual initial flight. For someone wanting to enter the scale jet territory, this could be a great plane to use to do so depending on their prior flight experience.

That is just one reason why I enjoy the models you all design, details like the use of pylons use as a safety precaution to help spare the fuselage and additional surfaces from damage. Also, one little detail I loved, and it may sound funny :), but........it was thoughtful that the paint surrounding the pylon glue points was removed from the factory. Now THAT made me smile right out of the box. In the past, I usually have to take a hobby knife, very gently cut around the shape to pierce the paint layer and add tape to the area to pull up just that area and not the surrounding paint. That was done to ensure proper adhesion of the pylons to the aircraft foam. Glue on top of paint is only as strong as the paint, and of course that’s not very strong, especially if it would need to hold up to a rare gear-up landing. On this model, I didn’t need to worry about that since it was done for me and cleanly at that. That gets a massive thumbs up for small details. I can be picky, ha-ha, and those details for some reason make me happy.

[Alpha]

I'm glad those small things don't go unnoticed. Masking the inner pylons is such a simple thing, but Freewing hasn't done it for years. Thank goodness that's in the past. We're backdating those updates where possible, also, such as with the Mirage's and F-86's pylon mounts.


Urrl, how is your black scheme holding up?

[T-CAT]

That is great to hear Alpha. Does Freewing also mask the servo pockets or other plastic pieces like mounts so it is a clean foam surface to glue them in?

[Rcfiddy1]

I posted up some parts I have broke so far. The gear doors and the little plywood rudder piece. If anyone else needs them here they are. Yes I banged the rudder putting the plane in my truck. I made a little change to gear door to try and prevent them from breaking. So you have the original set and the newer design to choose from. Also added a receiver shelf to mount gyro/receiver near CoG.

https://www.thingiverse.com/thing:3156665

https://www.thingiverse.com/thing:3156654

https://www.thingiverse.com/thing:3157358

[JazzmanB]

Speaking of pylons i never glued mine on the 39 and used the tanks on wingtips of flexjet. Win win. I love my clean airframe 39. Though i want that gun pod so ill contact motion;)

[seaviper]

I carry mine in on a stand in the car. I don't need the pylons.

I MAY hang a camera on that gun pod mount though.

I have a video of yesterday's flight that will be up shortly.

[Quickstop]

I have a bunch of planes that have drop tanks, but the L-39 is the only one that I will actually use the tanks in flight, maybe because they're fairly small and the don't pop off when I land

[seaviper]

Here is the video of our group aloft with two L-39's and an F-4 on Sunday. We flew loose on this day as our teammate "Dell" had only just maidened his L-39. The goal was to launch and recover, safely, three ships. This we did.

Next week we hope to have a full flight of L-39's.

[Flyboy79]

Hello Pilots I am trying to set up a RX600 SP in the new L 39 it with my DX18 G1 TX. The receiver works with the original function but the Gyro does not turn on. I have followed all the instructions on the videos that motion RC has posted any help would be highly appreciated thank you.

[RCjetdude]

Hello Pilots I am trying to set up a RX600 SP in the new L 39 it with my DX18 G1 TX. The receiver works with the original function but the Gyro does not turn on. I have followed all the instructions on the videos that motion RC has posted any help would be highly appreciated thank you.

Hello Flyboy79 and welcome to HobbySquawk. What lights do you see on it?

[RCjetdude]

Progress.... Tomorrow will be a touch up day but at least the paint is on it.

Again, here is a base shot...



And here it is just after unmasking for comparison. Close enough for me.

[TiredIronGRB]

Progress.... Tomorrow will be a touch up day but at least the paint is on it.

Again, here is a base shot...



And here it is just after unmasking for comparison. Close enough for me.

It will be perfect if I know you...and I do :Silly:

[PhantomNut]

Progress.... Tomorrow will be a touch up day but at least the paint is on it.

Again, here is a base shot...



And here it is just after unmasking for comparison. Close enough for me.

Looks awesome!

[JazzmanB]

Todays flight. What a perfect day at one of most beautiful places in the world. Im biased;) https://youtu.be/Ov0BB4lavvY

[Rcfiddy1]

Progress.... Tomorrow will be a touch up day but at least the paint is on it.

Again, here is a base shot...



And here it is just after unmasking for comparison. Close enough for me.

Wow, what a great job. I’m looking to do the exact scheme on mine.

[Planeclothes]

Hello Pilots I am trying to set up a RX600 SP in the new L 39 it with my DX18 G1 TX. The receiver works with the original function but the Gyro does not turn on. I have followed all the instructions on the videos that motion RC has posted any help would be highly appreciated thank you.

Make sure your dip switches are set correctly. https://cdn.shopify.com/s/files/1/10...P_Receiver.pdf

[yf22raptor]

Coming along waiting for callie graphics .. has hsd electric brakes and p -20 turbine going in .. then k -30 when it arrives ..

[JazzmanB]

Scale air show https://youtu.be/Ov0BB4lavvY