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Old Mar 02, 2012, 06:37 PM
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With the drop tanks on for show, and the retracts up.

The droptanks are - maybe - a nice protection for the wings if the retracts fail

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Old Mar 07, 2012, 04:48 PM
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nice looking model and good price for a composite 90mm edf model
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Old Mar 08, 2012, 06:09 PM
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Polyester resin fuselage, balsa built up wing ...

"composite" sounds good at first but is only half of the story, literally
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Old Mar 09, 2012, 10:17 AM
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Fitting the fan and ducting requires some patience.

First the fan mount got some extra epoxy (hysol) here and there ...

It's not that it is not strong enough. I am more worried about rigidity and later getting some rather annoying resonances and vibrations . A rather acute problem with FG fuselages, that tend to act like resonating violin cases.

My fan housing is a bit bigger than the ducting adapter supplied by CMP.

So the front piece had to be cut (as in the Hawk / T-45), and the back piece had to be cut, shortened and re-glued together.

The motor wires have to come out the side, otherwise they won't fit later under the belly fan hatch.

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Old Mar 09, 2012, 10:19 AM
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Almost finished with the fan installation ... quite a bit of duct tape and a few zip-ties still need to be added.

Even the fan hatch can be made to fit, eventually.

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Last edited by Herb; Mar 18, 2012 at 07:43 PM.
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Old Mar 11, 2012, 02:13 PM
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Retract and flaps operation video added :

CMP L-39 Flaps (0 min 17 sec)


CMP L-39 retracts (0 min 19 sec)
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Old Mar 14, 2012, 12:06 PM
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All closed up and ready for the maiden this weekend

That bottom fan hatch was a bitch to get in place, I used silicone, a long adjustable clamp, and four of the supplied wood screws to get it to conform - eventually - to the fuse shape.

The 120A HV opto esc is up in the front, with a small fan on top of it. Would have been impossible to get the CG with an ESC in the tail ...

Receiver battery is a 4-cell 2000 mAh Sanyo Eneloop pack.

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Last edited by Herb; Mar 18, 2012 at 07:50 PM.
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Old Mar 14, 2012, 09:26 PM
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Cool can`t wait for fly reports maybe video .
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Old Mar 15, 2012, 03:33 PM
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Good luck Herb!!
i still have a little more to go on mine
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Old Mar 15, 2012, 10:31 PM
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Quote:
Originally Posted by Herb View Post
your flap runs down Very slow? is that the norm on all your setup?
i always have mine on two settings, slow but not as slow as yours
i see also the inlet on the fan is not line up! Just like mine! is that OK?
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Old Mar 16, 2012, 12:49 AM
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Yes the flaps move pretty slowly in the video ... maybe not critical ?

If there are no pitch changes, you can drop them slow or fast ... If there are some pitch changes it helps to slow them down a bit ... I have it kind of scale, I find it cool. You can adjust the speed of course to your liking.

I usually put the flaps down on the last downwind leg. I prefer a slower gradual flap drop and, yes that's what I have sometimes (Hawk is same way). On the Me-262 there's no delay though.

Yes that fan inlet setup is not that great, but should be ok I think. No, it's definitely not perfect. I am still studying the thrust angle issue a bit.

It took me some work to get that fan hatch to conform to the fuse, I used silicone, hope it sticks for a while
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Old Mar 16, 2012, 11:49 AM
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Here's the Nitroplanes version / scheme of the CMP L-39 :

http://www.nitroplanes.com/cmp-cp09-090-kit.html

The HK one is due out any time I suppose ...
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Old Mar 16, 2012, 03:31 PM
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I kind of like the yellow wing tanks
helps to keep track of it in the air with my old eyes
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Old Mar 16, 2012, 03:38 PM
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Quote:
Originally Posted by Herb View Post
Yes the flaps move pretty slowly in the video ... maybe not critical ?

If there are no pitch changes, you can drop them slow or fast ... If there are some pitch changes it helps to slow them down a bit ... I have it kind of scale, I find it cool. You can adjust the speed of course to your liking.

I usually put the flaps down on the last downwind leg. I prefer a slower gradual flap drop and, yes that's what I have sometimes (Hawk is same way). On the Me-262 there's no delay though.

Yes that fan inlet setup is not that great, but should be ok I think. No, it's definitely not perfect. I am still studying the thrust angle issue a bit.

It took me some work to get that fan hatch to conform to the fuse, I used silicone, hope it sticks for a while
Imo as long the airflow is smooth inside the tubs, it should be fine
A lots of edf jets have all kinds of bends with their intakes!
where did you endup putting the ESC and Rx?
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