ltc

My Feedback: (3)

Looks to be a scaled up version of the T7 that was discussed here a while back
but comes in 2 other schemes besides red tail
No affiliation, just saw it while looking at other planes and parts



https://kingtechturbine.lu/JMB-Jets-...eing-T7A-PNP_1

Very detailed in PNP Version, all pre installed, scale electric Retracts with saquencer, tanks, scale cockpit, pipe and HV servos

Specifications:

Lenght: 3215mm
Wingspann: 2124mm
Weight dry: 19,5 kg

For turbines: 16-26kg max

Desertlakesflying

My Feedback: (28)

Lets hope this one is actually PNP......

Ceeray

Mini version is a tad too small and this one is too huge to haul around.

Maybe they come up with 2.5m version someday...

Desertlakesflying

My Feedback: (28)

The Fuselage design makes it very easy to move around. A lot of "hand holds" on these.

Ceeray

I got the XXL version of this bird last week eventually, in Canada scheme. Getting the plane was a real Bi*Tch..

I ordered it from JMB jets last October. Delivery was to be after Christmas, then it went to mid January. The container came and my plane was not there! I was given an option to get either different color scheme or money back. I choose to wait for the next container which was to arrive late April.. Well as we all know world wide shipping boomed really nice and one ship even tried to shut down Suez canal. And then the ship which was finally bringing the container late August broke down at Bulgarian harbour and whole load was unloaded and to be delivered via train. Well, snafu happened on the way , like Belarus, then it was stuck in Poland due German railway personnel strike etc. Long story short the large packages arrived eventually last week. And of course some a**hat had banged the package wall in. One wing took the hit, aileron broken.. Now I am waiting what to do with it, insurance claims done via JMB Jets but I am waiting..

But lets continue.
Its big. Its friggin HUGE! Its light. And to my personal opinion needs some carbon strenghtening in some critical areas. The landing gear looks good , its made by JP I think.
Also other stuff is done "chinese" way without understanding how forces go inside, IMHO. Wings are light and carbon tubed.

I will put 250XBL in it with AR26 and Jeti rx. Tail servos also will be changed just to keep my doubts in check to Hitec 9830 . The servos which came along are coreless digital GDW servos, they seem to be all right, no excess slop and 35kg torque.
I will post some pics which tell the story..




I will make the fuselage 2 piece. The rear fuselage will hold engine and taileron servos. Nose will stay on with the middle part so I can keep it standing on its legs.
The connection will be made with telescoping 16/14 and 13.7/12mm carbon tubes which will be connected to bulkheads. Some Unilight quick connectors for servos and 3-pin for engine.



Main Gear! Looks sturdy, practically F16...


I had to try fitting it into my car. YEAH!
It fits!

Ceeray

The damaged wing. Cracked. Hinges loose. pushrod bent to U..

Ceeray

Rudder servo and mounting. I had to tighten up the ball link, it had some slop. Main issue was that the pin hinges were "hanging" without support, so I hysoled plywood pieces to support them. No more slop / play.


Horn hole was too big. I added glue and made a new hole.
Also clevis had internal slop which was removed.
75% of slop removed. I hate sloppy linkage and controls.

Ceeray

Well next job was checking the flaperon of the other wing ( I wont touch the broken one until the matter is settled..).

I took linkage cover out and found out that the servo was connected to the hatch well but the hatch itself was attached only with little 2mm screws.. and this is a quite large control surface!! Not a good idea!


I decided to box the servo area to transfer loads into whole wing instead of bottom. I had only 5mm light balsa which I used so that the grain direction was from up/down to handle compression.


Then I did the same for hinges as I had to do for rudder hinges = I had to glue in plywood supports so that the flaperon would not flex and go into a flutter.



the flexing was really bad until this. Why dont they just glue some wood there at the factory..?

Ceeray

Rear end of the plane. Something went wrong with the layup as there is substantial deformation on the skin of the left tail side conpared to right. Again it seems to be inside manufacturers tolarances, no comments from vendor..

Ceeray

the engine and the bubble trap. This will be installed into my Eurosport and Intaircp trap from it will move here to suit the engines needs.

Ceeray

Cockpit.. I may end up tinting the canopy or even using latex paint to paint it black from underneath to save weight and keep it simple. Installing these cockpits with pilots would add at least 600g ..

Upper pics are internal structure. How much extra would have it costed if real birch ply would have been used instead of liteply..

Ceeray

Taileron servo assembly. Servos are attached only with 2 m3 bolts. I will add another pair. Also I will swap them to Hitec 9830 servos just in case. The taileron is barn door sized so..

The linkage looks good but I will do some testing and I will take all slop out.

Ceeray

I managed to make the two largest fuselage halves easier to connect to eachother as I have to do this every time at the field.

16/14mm carbon tubes glued to connect four bulkheads, the tubes are cut so that they are aligned with the seam of the fuselage halves. Then its aligned with 14/12 carbon tube which are full lenght inside the larger ones, connecting the halves. So the larger tubes are guides only.




Tadaa, the patient is still alive after gluing and cutting. And it works, I managed to align the tubes correctly.

Next is elevators!

jcterrettaz

My Feedback: (1)

well done

Ceeray

Elevator servo was flexing too much, so I had to add additional former (encircled) to get the whole assembly ridig. Also servo bracket was attached only with 2 M3 bolts. I added 2 more.

Few days break now for building , its time for flying.

I sure hope this cures flexing..

mhadjiky

Please find attached some pictures from my JMB Boeing T7A XXL. Is powered by Jet Italia Atom 270, CG set to 195mm back from wing leading edge (wing root), UniLights lighting system installed. To fit it in my VAN I remove the nose. I found this as the easiest way.

Ceeray

Yep, for fitting into a van its easybto remove the nose . The rest of the fuselage is so bloody wide so it wont fit a touring car unless front passenger seat folds flat.

Agrav8ed

Any maidens yet? Fight vids?

Ceeray

Mine is not ready until next spring for maiden..

lookilook

Maiden flight of Marios aka Mhadjiky

Ceeray

The plane looked to be a bit unstable on roll axis and some tail wiggling...

Desertlakesflying

My Feedback: (28)

Flying around with the gear down will do that.

lookilook

Indeed, there was an issue with Nose gear not retracting so all gears remained down.
Apparently this was fixed after the motor was replaced.

Agrav8ed

How are the stock lights? How are the control surfaces? Are they fairly slop free?
Thanks,
Tone

Ceeray

All surfaces need checking. Rudder slop was quite big until all free play was removed from hinges/linkages. And still I am not completedly satisfied. The geometry is not the best one.. too short linkages/horns , amplifies every slop.