New FB Jets Large L39
 

Hi guys,

Thought I'd let you know that my 1:4.8 sized L39 arrived on Dec 30th kindly organised by Martyn Little of AceJets.

This is a new model from FB, this version is riveted, panelled and constructed using Airex and carbon reinforcement all over..

After much deliberation and grieving over the loss last season of my blue and white JL L39 I decided to pull the trigger on this one, just couldn't resist it.

I'll give you an idea of the construction as it goes along and a few observations on the model.

A few pics to show you a little of how she looks, although only 5 or 6 inches longer than 1/5th scale this is one big model, by my standards anyway,

I've done a search on this forum but can find nothing related to this particular model, please feel free to chime in if you have one,

Cheers,
Gary.

A little more......

This will be guided by a Jeti DS16, 2 Rsat2's through a Powerbox Competition SRS and for my first time a Cortex gyro for stabilisation, talked into that by Al, good enough for him, good enough for me!

I am also for the first time using a Unilight system which so far is assembling and working nicely, difficult to set up without blinding myself though!

As I have no idea yet what the all up weight will be I'm not sure which turbine to install, I have a good Wren 160 Kpro but not sure whether it will provide enough oomph, an alternative would be my PBS 210 newton but that may be a trifle too much power and weight.

Ideally I suspect a 170 sized turbine would be perfect, will have to wait and see.

gary I love my JL l39 as well it is identical to yours and also has a wren 160 in it and If I was to replace it I would also try the FB one, I would have though the 160 would power it well as the jl version is at half throttle in the cruise.
more pictures please.
I am waiting to see what the JL 1/5 yak is like before I push the button on another kit, I also have the 1/6 f16 which I my favourite at the moment
it does seem like JL are putting their prices up which is a shame but it does make the fb kits look competitive

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Looks great! Looking forward to seeing the build.

It's going together much faster than I thought, partially because all the control surfaces are pre hinged, I'll take some time to post a few pics tomorrow, so far I'm quite impressed with it.

was it a custom scheme?

Yes, owned privately by a guy in South Africa, colours aren't quite correct but it looks so nice I'm not complaining, nice to have something a bit different.

This is how it should look.

Wings being prepared, lots of carbon inside in all the right places, structure and gluing looks very sound.

Scale nose hatches, front and rear rc plates, turbine mounting area.

Rear fuse, hatch and air brakes.

Scale cockpits, one of the drop tanks and wing tanks, installed navs, strobes and landing lights from Unilight.

More stuff tomorrow, if anyone needs any specific details or pics please let me know.

This model is going together nicely and quite fast by my standards, so far I can't really fault the kit which makes a nice change.

The only exception to that statement is the cylinder pivot installations. Air brakes, doors and front hatches were obviously done by some minion in the factory as the ply ram pivots are not equal on any of them. You can see in the pic that the air brake pivots on the main spar outer tube are a good 1/2" out and the brakes don't open half as far as they should. the hatch pivots likewise but they operate ok, One of the main doors is out a little on the offset hinges and the inner part hits the fuselage bottom when open but not too serious.

The rear fuse is all but finished now, pic shows the final stage of air lines, rc cables and light cables installed, just the turbine and thrust tube to fit.
Three air tanks are connected but not yet glued down, One large and one medium tank will be dedicated to the landing gear, the other large one will do wheel and air brakes, doors and hatches.
Air fill and gauges installed in turbine area, all other things I need to access will be in the nose eliminating the drag of ripping cockpit detail out to service fuel, battery connections and Powerbox switch access.

Yesterday attention was turned to the pointy bit, the hatch cylinders were a pain to access for cleaning piston rods and connection tubing.
The nose gear was taken out for inspection, steering servo fitting etc.this made it easier to connect the front door cylinder tubing and routing.
Nice inner cover to stop air entering (same on air brakes and rear doors), this is a nice touch by FB but does make installation a bit trickier.
This cover will make it easier though to attach batteries etc to and save the extra weight of plywood mounts, good 'ole Velcro here!
I do very much like the retracts in this model, substantial 1" cylinders (neccessary on the L39 because of the forward retracting of the leg).
Note the way the cylinders are attached, very simple to remove for servicing, another nice touch, no doubt about it the Chinese manufacturers standards and design are improving rapidly, maybe FEJ scared them a bit with their adverse publicity!
Front airlines not tidied up yet.

Thought you would like to see the fuel tank, all 4.1 ltrs of it, odd shape so a bracket will have to be made to support it, I bought a nice profile gauge to assist in this.
The front cap has already been glued in place although I would have preferred it a little higher, on close inspection it looks as though it may leak, couple of gaps in the glued area but a test will show this up of course.
The air tubes have all been pressurised before connection to the valves etc and everything appears to work fine, if I have a leak it will be a nightmare to find it.

did u order unilights or did they come with the kit? I have a FB Dolphin coming and was interested in the light for it.

No, not with the kit, ordered from Martyn at Ace jets UK the importer, never tried Unilights before, they are very good and not that expensive.

Ground testing
 

Got fed up taking pics of bits so here's the real thing assembled for ground testing today.

Do you have maiden video?

Sorry, no.

What's the CG?

150mm

I am thinking of getting the FB big L39. Did it come with lenses covers for the tiptank lights. and which unlight set of lights do you have on.

Hi!

The lense covers are included (and so are lots of other small scale parts such as antennas, fins etc). I use the optotronix / emcotec L-39 light set and I found them to be much more brighter in daylight then the unilight LED's

/T