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Old Jan 26, 2012, 12:47 PM
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Aero L-39 / L-59 Albatros 90mm EDF composite by CMP (RC Aerodyne / Hobbyking L-59)

The long awaited CMP (aka CMPro or China Models) Aero L-39 / L-59 Albatros 90mm EDF

http://www.chinapro09.com/OEM%20airplan/L-39.html is now out.

This thread in German

This thread in Italian

Given that the original had a wingspan of 9.46m and a length of 12.13m (L-59: 12.20m), whereas the model has a wingspan of 120cm and a length of 132cm, the scale is approximately 9.46m/1.20m = 7.9 :1 .

L-39 : http://en.wikipedia.org/wiki/Aero_L-39_Albatros

http://www.airwar.ru/enc/other/l39c.html

http://www.airwar.ru/other/draw/l39c.html


More info on the kit :

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

http://www.scaleflying.com/Aero-L-39...an_p_2522.html

http://www.hobbyking.com/hobbyking/s...00mm_ARF_.html

http://www.x-flight.com.hk/?sp=&p=6&...&cat0=1&id=159

http://hobbyfly.de/en/rc-airplanes-1...00mm-6767.html

http://www.ready2fly.ch/shop/USER_AR...anzeigen_ab=0&

The retracts are exactly the same as the ones sold for the CMP / HK Hawk :

http://www.hobbyking.com/hobbyking/s...dProduct=19949

I got mine from RC Aerodyne and it arrived, double boxed with no damage.

Edit: CORRECT CMP L-39 CG AFTER THREE MONTHS OF FLYING:
ca. 75-78 mm from wing leading edge at root (see picture below)



Short Video of mine (April 2012) :

CMP L-39 (Hobbyking L-59) Albatros 1200mm EDF (5 min 52 sec)


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Old Jan 26, 2012, 12:50 PM
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It is almost identical in size (both 1.2m wingspan) to the Savex L-39 90mm which has been around for a while

http://www.savex.cz/prod.php?lang=en&id=10

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Old Jan 27, 2012, 03:31 PM
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Today I got the retracts, took two days from RC Aerodyne:

This what the CMP/HK retracts for the CMP L-39 look like.

http://www.hobbyking.com/hobbyking/s...dproduct=19949

The mechanism seems identical to the one HK sells for $8 - so I already have spares

http://www.hobbyking.com/hobbyking/s...m_1pc_54g.html

The only difference is the nice metal trunion. In case of need, I assume the whole gear leg (including the metal trunion)
can be taken out of of the plastic electric retract housing and put in a new one.

Note that part of the strut is machined hardened steel, not aluminum ! You can see it has a different shine.

The springs are WAY too soft for the L-39 / T-45 / Hawk, will have to look for new much stiffer ones at Ultimate Hobbies.

The 3-way Y cable and the screws were NOT included in my box.

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Old Jan 28, 2012, 07:58 AM
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Quote:
Originally Posted by Herb View Post
The mechanism seems identical to the one HK sells for $8 - so I already have spares .
Thats the only problem I have with the price. So you are paying $130 for the struts. Will scaleflying's prices ever come down? Do they have sales?
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Old Jan 30, 2012, 12:08 PM
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For the L-39 struts there are always other choices (provided they can be made to fit) ,

such as these $129 Tam struts:

http://www.tamjets.com/original/prod...bc880a8a930211

or these $135 Behotec C21 struts:

http://www.altecare.com/struts.htm

or the $129 Sapac struts

http://www.espritmodel.com/sapac-min...ts-t45l39.aspx

I prefer to go with what is in stock, and I know will fit

The struts have to be dimensioned properly so they can hold up on an 8lb edf jet.
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Old Feb 01, 2012, 07:55 PM
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The above retracts fit well in the CMP L-39 wheel wells

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Old Feb 03, 2012, 12:25 PM
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Bare weights:

fuselage : 31.0oz = 880g

ducting : 5.5oz = 156g

tail fins : 3.1oz = 88g

wing: 13.0oz = 369g

wing tip tanks : 6.0oz = 170g

belly pan : 1.4oz = 37g

misc. parts : 3.4oz = 97g

underwing drop tanks : 5.9g = 167g

retracts : 12.7oz = 360g

--------------

Empty airframe weight (without drop tanks and retracts) = 63.4oz = 1.80 kg

The same numbers for the CMP T-45/Hawk add up to ca. 58.4 oz,
so the L-39 airframe is only slightly heavier (ca. +9%) but with a bigger wing (29.2dm^2 vs 24.0 dm^2, +22%) .

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Old Feb 03, 2012, 05:11 PM
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Just like the CMP Hawk, which is available in at least three color schemes (T-45 Goshawk, the HK UK Flag scheme, and another black/blue UK scheme), also the CMP L-39 is available in at least two czech color schemes.

CMP as a company has been around for while and has made lots of gas planes, some of which fly very well. I have a Spitfire Mk. IX which flies like a bat out of hell, and friends have the F4U Corsair, and lots of P-51'a in various sizes have been flying at my field for years. I think one of my buddies has a 90-sized CMP Zero. The large CMP Bf-109G is a work of art, with the usual annoying ground handling characteristics of all 109's.

CMP knows how to design airframes, the quality - in this price class - is at least as good as Kyosho or H9, most of the time.

Generally CMP airframes are not the lightest. They almost all have nicely molded fiberglass fuselages, which look very good but tend to be a bit on the heavy side, both on the EDF's and on the gas warbirds.

The CMP Hawk / T-45 and the L-39 are no exception. The fuse is a bit on the heavy side, and so are the wingtip tanks. This is in part compensated, in all of the above cases, by having a very lightweight balsa built up wing. The wing is strong enough for the Hawk / T-45, and the hope is that it will be likewise for the L-39

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Old Feb 04, 2012, 02:07 PM
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As for the T-45/Hawk, the ducting is well made and seems to fit well.

CMP designers must have attended again the Rodger International School of Ducting ...

Actually, the intake has a bend that's a bit sharper than needed (maybe).

The rear duct by itself is only 44 g, so there's not going to be any weight saving in replacing it with a mylar tube (plus this one fits well and pushes in / pulls out easily).

It seems CMP learned from the experience gained with their first EDF (the Hawk/T-45) and improved on the duct design / fit.

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Old Feb 04, 2012, 02:17 PM
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Some more kit details ... Mostly the fuse inside and formers. Well made and rigid.

Very similar to the CMP T-45/Hawk construction, everything seems to be glued in securely. No complaints so far.

Nothing came ever loose in my T-45 in a year of flying (except the steering servo tray).

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Old Feb 04, 2012, 02:19 PM
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Detailed views of the wing ...

I plan to add full navigation lights.

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Old Feb 04, 2012, 02:38 PM
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For navigation lights, I will use this $7 set which I've had for a while. Works well, take out of the box and plug in ... done

http://www.hobbyking.com/hobbyking/s...idproduct=8850

The wiring is 24'' = 60cm long which hopefully should be long enough for the L-39 wing (120cm wingspan).

For the flashing strobe I will use this one which is really bright. It runs at 300V. I have one in the CMP T-45.

http://www.hobbyking.com/hobbyking/s...ght_Unit_.html

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Old Feb 04, 2012, 07:20 PM
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A trial fit of the various parts suggest that the wing has a bit more surface than the T-45, which should give a slightly lower wingloading for comparable power setups ...

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Old Feb 06, 2012, 11:50 AM
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Hobbyking decided to call the CMP Aero L-39 Albatros an "L-59"

http://www.rc-network.de/forum/showt...-90er-Impeller

It looks to me like it's the same identical CMP L-39 kit, in a different color scheme.

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Old Feb 06, 2012, 12:43 PM
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Nice detailed Aero L-39 / L-59 Albatros 3D drawings from the airwar.ru site:

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