My throw settings, JetLegend L-39 ---------------------------------------- All throws are measured at the surfaces at the closest side to the fuselage.
Elevator : 35 mm UP/DOWN and -20% exponential Ailerons : 25 mm UP/DOWN and -15% exponential Rudder : 45 mm LEFT/RIGHT Nose wheel : approx -35% exponential, with very short turning circle at max deflection and very soft and precise correction in the center range of the rudder stick. Flaps : 0 mm horizontal, 72 mm down at max flap Throttle : the P-160 has most power in the top range, I had too little 'feel' in the lower throttle positions (bottom 3/4), so I added a lot of exponential to spread the top RPM range over more stick movement and for having steeper RPM increase from idle position to 3/4 position.
My CG = exactly as per the plan, the plane hangs perfectly flat on these points (w/ only BVM UAT filled with fuel). Had to add 796 grams in the tip of the nose to achieve this point ! Not sure yet if this is the best CG, hence : to be confirmed.
PS. 1 inch = 25,4 mm
Nicolas.
< Message edited by SpiderJets -- 11/2/2007 8:59:38 PM >
Posts: 275
Joined: 1/28/2002 From: Scottsdale, AZ, USA Status: offline
Hello To All,
Well Today I flew my JL L-39 with a new JetCat Titan, I have been flying it with a JC P120 and my conclusion is that the Titan is a better match up with this Jet. The Take Off was right on the step, with authority and quick response. The Gear went up nicely, and cruising at 1/2 stick gave a quicker nicer handling plane. The landing was no different, and it seems that fuel consumption is only slightly more. I had a 5 minute flight with fuel left over, and I plan now to add a third tank to acheive the 7 to 9 minute flight. I have 20 flights on the L-39 now and each flight is getting better and better. I really like this bird, and spectators really like the profile in flight and on landing.
I have made some more flights on mine too, with better throttle control due to exponential throttle curve (more spread of the top RPM over wider stick range). My landings are now as per Kevin's posts : full flap and 1/3-1/2 power. Really nice. P-160 gives it superb performance, my flights are 6 minutes, the alarm is set to 7 and I have just enough fuel for safe flights. Digitech's larger UAT hopper tank might be an option, or install 2 cola bottles of 2 liters ? Anyway, I am happy with the capacity myself now.
Batman and his latest chick took the controls and without any doubt, the plane flies now much better. Perhaps it has also to do with the CG being a bit more forward. The pilot and his girlfriend weigh in at about 280 grams, I took some 100 grams lead from the nose (the pilots are half way the CG and the nose). The stall tendency is much less now too.
The oleo spring in the nose was replaced with a heavier spring from an old Robart strut, cut off at length 2". Now it is perfect and the plane 'sits' correctly on the tarmac.... errr... grass.
PS. Note the purse and sexy boots which my friend Pedro taped in the cockpit interior while I was having a coffee !
Enjoy, Nicolas.
< Message edited by SpiderJets -- 11/5/2007 6:27:57 AM >
Nicolas, it's great to have you back in the jet community again! I see you still have the router machine, very nice details with the perfectly done parts with words routed into them!! It's also fun to see the old SpiderJets bypass, air gauges and other stuff that I recognize from my two F-16's. You remember there is still an unbuilt SJF-16 here in Norway - I'm not sure this guy will ever build it..
Congratulations on the maiden, and I hope to see you in Norway soon!
Posts: 333
Joined: 6/9/2005 From: Cardiff, UNITED KINGDOM Status: offline
Miguel, Nice video the L39 looks very good in the air. Lovely landing & roll out.
Nicolas & Kevin, Looks and sounds like you are both having a lot of fun with the L39. Just waiting for mine to arrive. Nicolas, Are you using same c of g as Kevin? What is the tank capacity as standard? All the best, John C
Very nice video but such a shame that two different planes are mixed. Your L-39 seems to be less stable than mine ; but at least I see you have the same landing approach glide angle and speed as well. When reading Kevin's posts, I thought I was doing something wrong and flying too fast. I'll test also the opened air brake during landing with some more throttle next time, just like you... Who knows...
Tank capacity of the fiberglass tanks is exactly 1660 ml each, check it out ! (+ BVM UAT : 125 ml // or Digitech's UAT : 250 ml)
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John,
The CG, I haven't re-checked it, but I will not be wrong saying that if you have the CG as per the plan with the plane hanging perfectly horizontal, it is a tiny bit tail heavy. I would add the weight of one single servo (about 45 grams) in the nose from that point and you should be perfect. Give us some more time to test it all....
Two 2 liter bottles for 8 minute flights wouldn't be bad... (see previous posts)
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Todd,
The air brake hinge line : exactly 1" (=+/- 26mm) from the front of the airbrake ! Sorry for being so late ! I wrote it on my arm not to forget it this time !
Hi John how long ago did you order your L39 ? I have mine on order since JETPOWER I did get a few e-mails from JETLEGEND telling me it was ready for delivery but still no signe or tracking No .
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RE: What do you think about JETLEGEND L39? - 
