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A-4E Skyhawk mod.

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A-4E Skyhawk mod.

Old 02-02-2014, 11:57 AM
  #26  
cmjets
 
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Olá Enrique:

Congrats for the maiden !
Regards from Spain.
Carlos
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Old 02-02-2014, 04:22 PM
  #27  
erbroens
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Thanks Carlos! now to make some improvements on the installation and a lot of scale things in the plane... some wing tanks would be great.

fuerte abrazo amigo!
Old 02-05-2014, 07:19 PM
  #28  
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And talking about the wing tanks they are huge compared to the size of the airframe .. 3 foot long and about 5 inches wide. found this foam cilinders in a shop and with 4 of this and a foam lathe and some fiberglass I will be able to make them.

I also bought some depron /cardboard sheets used in archictectural models and started building a cockpit. In this shop I also bought a white poliestirene sheet to make some other details, like this antena behind the cabin. I sadwiched some FG and CA glue in the assembly and it turned out well. It´s light, rigid and very quick to make.... of course having visited the full size airplane and being allowed to get into it helps to reproduce the details in the model.. this visit happened by sheer luck and was a unexpected and pleasant surprise!

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Old 02-07-2014, 07:04 AM
  #29  
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This is my foam lathe setup.. don´t do this at home if you want to keep married! Just two workbenches, a drill , a plywood square with four nails and a speed controller to keep the rpm about right to sand the foam. I started with a iron brush, then 80 and 150 grit sandpaper. Using a mask while doing this is a good idea. I worked in each half of the tanks and then I glued the two parts together.

The electronic pod also was shaped and sanded from foam.. haven´t seen it this shape but in the Argentinian jets.. All this will be fiberglassed and painted.

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Old 02-07-2014, 07:54 AM
  #30  
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Erbroens,
Great ingenuity!
Pip
Old 02-07-2014, 07:59 AM
  #31  
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I still haven't resolved my A4 gear issues with Comp ARF.. the bird sits in my garage collecting dust
Old 02-07-2014, 09:05 AM
  #32  
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Thx Pip!

Andy: Is a pity it didn´t flew yet. I think you would love this plane, specially yours that have a functional and scale slat system .
Maybe you can give a try differential breaking steering, like some full scale early models have, or even put a flexible cable pushrod with a servo somewhere inside the fuselage.
Old 02-15-2014, 05:31 PM
  #33  
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Just a very few hours of extra work this week... the ECM pod was glassed and painted but not with epoxy, but with water based poliurethane wood finish and CA glue.. seems that is easier and less messier than working with epoxy and the results seem good.

The tail hook was made of a tube of aluminum and some balsa.. and some more cockpit work: The panels and dashboard looked flat, until I glued some short pieces of a paperclip imitating switches with a small blob of white or red paint at the tip of them. My biggest accomplishment was using zip ties with shrink tube for the control stick, throttle and ejection seat handles.(!)
Lots of fun doing this at my mancave in a lazy, rainy saturday....

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Old 11-15-2014, 09:08 PM
  #34  
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A miracle happened, A sunny saturday in Curitiba! Took the A4 for a flight and burned some kero, and a friend recorded a takeoff and took a pic of this plane.. it was a fun day.


https://www.youtube.com/watch?v=5L7s28HhZPo


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Old 11-15-2014, 10:07 PM
  #35  
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I have a fix for the nose gear steering. It's rock solid. I just don't have time to do it right now. I'm working on my JWM F-89 Scorpion. It will come later.
Old 11-16-2014, 04:39 AM
  #36  
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nice job
vinny
Old 11-16-2014, 07:09 AM
  #37  
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Thanks Vinny, and great to know you found a fix for the gear Andy.. The F-89 is a great plane no doubt and very competitive as it is rare, but each A4 flight feels to me like winning the WJM, the F1 championship and the lottery together! ;-) You will love yours.
Old 10-15-2015, 09:10 AM
  #38  
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Flew the A4 in Argentina last weekend.. a 5.000 Km round trip from home but well worth it! The small guy flew very well and also a unexpected meet with war veterans who where very interested in the plane and in the sound of the turbine engine.. it was supposed to be a short stop a the museum after the jet event, but met this guys and the war stories where a must to hear.. it was a great evening of flights and talks.. guess that this long road trip is one of the best I made... now I am back in Brazil , a tired but happy man! :-)


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Old 05-13-2016, 07:05 PM
  #39  
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And back in Brazil, a couple of weeks ago... I enjoy this jet like no other plane!

https://www.youtube.com/watch?v=pfd3DdAflTU
Old 05-14-2016, 01:50 AM
  #40  
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Originally Posted by Vincent
I built one of those about 6yrs ago. I got the kit from Don Kanak and flew it many many times. IMO it was one of the most stable jets i have ever flown. I never saw any sign of this jet departing early in slow flight. Flaps were comfortable at 35d, any more it caused some severe nose down issues.
V..
+1
Old 05-14-2016, 01:52 AM
  #41  
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Originally Posted by jackjet
make sure the a4 is not tail heavy - this 95% of the problem with tip stalls.

Jackjet
yep..
Old 05-14-2016, 02:03 AM
  #42  
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Default Tip stall

Originally Posted by erbroens
well guys, this is a new experiment. This is a 7 years old a-4 skyhawk molded in honeycomb...
Done by a brazilian guy living in miami . The problem with this kit, as far as i know, is
that it has the nasty habit of snapping at take off. ( the 2 other kits built here in curitiba where lost
in the first flight) , so the original owner lost interest on it...

Having witnessed both crashes, i thought that it deserves a chance, as long some mods where built
on it. The problem is that i really like the a-4 ,and i want to stay as close as possible to the original ,
without changing too much its looks.

The full scale a-4 didnâ´t have this tip stall tendency at all written in the history books, i think that the
slats where part responsible for this, so i drawed a fixed slat / leading edge drop on the scale wing.
Mr.patake worked so fast on it that i didnâ´t have pics of the early opened wing structure... Also the
horizontal estabilizer where slightly enlarged too.

Letâ´s see what will happen with this scooter!


Rgds, enrique

tail heavy!!! To much "up elevator"

YOU WONT LIKE, RESULTS OF YOUR MOD >> SORRY BIGGER "FLAPS" WOULD HAVE HELPED MORE

YOU COULD JUST HAVE ADDED "CROW"


THIS JET IS FOR SALE.. NEVER FLOWN ,18 LBS
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Old 05-14-2016, 06:10 PM
  #43  
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I am pretty sure that I have the easiest and more relaxing flying rc turbine A4 in the world!

Very satisfied with this mod, and with the many things I learned this past years and flights with this model, I will build a better and bigger skyhawk.... with a slightly different solution that will look scale and hopefully fly as well or better than this one. :-)

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