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Sig King Kobra

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Sig King Kobra

Old 01-10-2006, 10:35 PM
  #1  
Flipper430
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Default Sig King Kobra

Purchased the kit and waiting for it to show up.Thought i would ask if anyone has any Mods/Tips on this kit prior to building it,this is only my second build.Was thinking of starting a build thread if time permits.Would appreciate any and all comments.

Dan
Old 01-11-2006, 10:15 PM
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rryman
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Default RE: Sig King Kobra

Don't know what your first build was, but depending on what you're doing to this kit, it may be a challenge. I've built 3 of them, all with retracts. It's fairly straight forward building. It flies great, and slows down fairly well for landing. It gets a little cramped in the nose when putting in the retracts. I used an MDS .68 for power. It was adequate, but an OS .91 would make it outstanding.
Good Luck,
Randy
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Old 01-30-2006, 11:57 PM
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jmikesh
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Default RE: Sig King Kobra

The only mod I do is with the landing gear blocks...the blocks will "give" with time and use installed as per directions...I add ply at right angle to the ends of the l.g. block..adds a lot of strength without lots of weight.
Old 03-31-2006, 07:32 AM
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i4ni
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Default RE: Sig King Kobra

I also have a King Kobra kit. An build thread were great. I miss some Information about the engine. Is it not necessary to give the engine an angle?
Sorry, I don't now the English word for "Motorsturz".
Old 03-31-2006, 11:23 AM
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MikeRuth
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Default RE: Sig King Kobra

Just wanted to pipe in here and say that I had built a King Cobra some years back and changed it to a tail drager with retracts in the wing, Was an excelent flyer.
MOst people didn;t know what it was at first. I also built it up with dual aileron servos and and used elevon mixig, this baby would hang right to the last inch before touch down, and yet fly like a jet at speed.
You'll like it

Old 03-31-2006, 02:13 PM
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i4ni
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Default RE: Sig King Kobra

Here are some pictures about "Motorsturz"and Motorzug", so you can see what my Problem is.

http://www.modellflug-freakshow.at/B...mage/sturz.jpg
http://www.modellflug-freakshow.at/B.../Image/zug.jpg
Old 03-31-2006, 05:18 PM
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SteveW
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Default RE: Sig King Kobra

i4n1,

From your photos I see that Motorsturz = down thrust and Motorzug = right thrust. I don't remember if the King Kobra requires either. I'll check my plans that are stored out in the garage and let you know.
Old 04-16-2006, 02:27 AM
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i4ni
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Default RE: Sig King Kobra

@rryman

Can you give us more tipps how do you build your Kobra? What retracts do you use? How do you build up the Foam Wing? Do you have more pictures of your Planes?
Old 04-16-2006, 12:09 PM
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stang
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Default RE: Sig King Kobra

One tip that I tried was to cut out bays from the foam wings before I sheeted it. I ran a strip of carbon fibre down the spar and then sheeted the wings with balsa. It saved some wight and flew great.
Old 04-16-2006, 07:37 PM
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blw
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Default RE: Sig King Kobra

i4ni,

Offset angle. It is to counteract engine thrust and the pull to the left. Nice pics and very nice looking twin engine!
Old 09-20-2007, 04:07 PM
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dagored11
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Default RE: Sig King Kobra

Just picked up a used King Kobra - where exactly is the CG? How far back from the leading edge?? Thanks
Old 09-20-2007, 07:03 PM
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WMB
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Default RE: Sig King Kobra

I received this kit today. CG for test flights is 5&5/16" +/- 1/8", this gives a 25% MAC. quote from manual- "Our findings with 5 prototype models show that 1/2" behind the 25% point is as far back as ever will be necessary. Under no circumstances should the C.G. be moved further back than the 33&1/3 % point."

I am flying the Kobra currently and wanted to build the biggest version. I want to make a few mods based on how the Kobra flys, hopefully for the better.
1- Bring the fuse together at the rear, rather than have the box at the back.
2- Increase the depth of the fuse at the rear.
3- Split the elevator in the middle.
4- Lengthen the rudder to run to the bottom of the fuse.
5- Build a tail dragger version. Undecided on retracts at this time. I haven't played with retracts and don't want more maintanance due to sloppy landings. Maybe go with wheel pants?
6- Servo for each aileron.
Did I miss any?

If I can get the tank mounted low enough in the fuse, I will probably invert the engine for a cleaner look. I'd like this to be a ROCKET, but I know it is fairly draggy. Engine will most likely be a 90 two stroke, but the OS 120AX sounds like a great engine. Would it be to heavy? I'm not a light builder, but will try to reduce weight where I can.

Any tips for the build?

TIA, MikeB
Old 09-20-2007, 09:20 PM
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Default RE: Sig King Kobra

i am installing spring air retracts, adding individual aileron servos, flaps (for the hell of it), rudder and elevator controls will be internal fo r looks. i will add pictures tomorrow
Old 09-28-2007, 12:27 AM
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MustangUSMC15@hotmail.com
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Default RE: Sig King Kobra

I have built and flown 2 Kings and I have to say they are best flying air craft of their size anywhere. The first one I flew for 3 years until it was just worn out. The second flew just as good as the first and I ended up having to sell it because I was moving. Both were dressed out with tuned pipes and retracts. I will start on a third in about 2 weeks. I plan on using an OS .61 with tuned pipe, retracts, and flaps. Of course this one will be dressed up in the Blue Angle color scheme and dressed the landing gear up with Spring Air struts. Why? Because I can. I am putting the finishing touches on a Sig Kougar because to me its the little bother of the King Kobra. I have two giant scale air craft both Cardens and though they are good aircraft, to have fun you fly the afore mentioned aircraft.
Old 10-12-2007, 11:19 AM
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Default RE: Sig King Kobra

Just finished a King Kobra for a friend. Not a bad build, but I didn't like the options for rudder pushrod placement. How does this bird land? Fast, stable? I've been looking for links about flight characteristics, but haven't found any. Oh yeah, somehow I got her to weigh about 6.5 lbs. She's got a Super Tiger 61 and Hitec standard servos. I don't know how it came out 1 lb light (I'm pretty sure I didn't leave out any balsa ). I did use Gorilla Glue for the wing skin lamination and wood glue for most of the rest of it.
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Old 10-12-2007, 12:00 PM
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Default RE: Sig King Kobra

That's a pretty sweet looking King Kobra there, Fred!
Old 10-12-2007, 12:04 PM
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frednjess
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Default RE: Sig King Kobra

Thanks BidEd! You should meet the guy I built it for. What a slave driver! See ya at 6:15 for the maiden!
Old 10-12-2007, 03:42 PM
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MustangUSMC15@hotmail.com
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Default RE: Sig King Kobra

The King Kobra lands nice. If memory serves the KK is a very stable aircraft and pretty easy to land. On final simply cut power and guide the plane in. I can never remember slalling the aircraft on landings and I have had it slowed down to almost a walk. Can be brought in with the nose high for a perfect touch down on it's mains. Matter of fact I installed a wing skid on the tail to keep from scratching the covering on nose high landings. Again, on final allow speed to reduce and you will find the KK will make you look like pro. Hope that helps.
Old 10-28-2007, 12:00 AM
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Default RE: Sig King Kobra

Well MustangUSMC15, I got a chance to maiden my King Kobra this afternoon with plenty of help from frednjess and Nathan King. I let Nathan land it since he's been flying his SPA pattern planes recently so I figured it would feel pretty familiar to him.

Nathan says the landing is nice and uneventful, just like you said. The Super Tigre G-61 dialled in nicely after 3 tanks on the ground, but it will need some more running in before the idle will settle down to a gentle purr. Other than coming in a little hot because of the high idle speed, it seems like landings should be a pleasure.

The King Kobra is going to be a plane that will actually get better with age. The more runs on the engine and the more comfortable I get with the airframe, the more fun it's going to be to fly. I'm not only looking forward to my second flight with my new King Kobra, I'm also looking forward to my one hundredth flight.


Old 10-28-2007, 12:43 AM
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MustangUSMC15@hotmail.com
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Default RE: Sig King Kobra

I am glad the maden of your King Kobra went well and you are right, the aircraft will get better with age.
Old 10-28-2007, 11:13 AM
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frednjess
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Default RE: Sig King Kobra

I am the greatest builder ever to walk the earth! Mwa ha ha ha!.....I guess you had to be there.
The Kobra flew like it was on rails! I think the only problem was that the thrust angle was a little off. At full power it climbed slightly, but other than that it only took two clicks of right aileron. Not bad for a maiden. A couple of washers ought to take care of that thrust angle problem.
The thrust angle might explain why the plane took off a little early. BigEd started applying power and got a little above half throttle when the Kobra, very gently, lifted off on its own accord. Just ask BigEd!
Old 10-28-2007, 12:28 PM
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Default RE: Sig King Kobra

The King Kobra will make anyone look like an expert builder and pilot. I am glad that you are a happy owner of one of if not the best 60 size RC aircraft to date. After reading your message this morning I ran out to the shop to see how things were going with my KK. I am about ready to sheet the wings after getting the retract wheel wells ready. This KK will be tricked out but good. It doesn't need it but after having built two other Kks I figure why not. Each aelerone will have it's own servo so if need be I can program my radio for flaperons. Landing gear will be the new Spring Air Stuts for looks and other assorted modifications as they come to mind. Hope to send you a pic when its all done.
Old 10-28-2007, 01:13 PM
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Default RE: Sig King Kobra

Mustang, I used Gorilla Glue when sheeting the wings and titebond 2 on the rest of the build. Don't know exactly why, but it came out around 6.5 lbs dry. Nothing wrong with 1 lb light! Thought you might want to save some weight since you're doing retracts. The gorilla glue is really light when it cures as all of the water evaporates out.
Old 11-11-2007, 11:39 AM
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Default RE: Sig King Kobra

i'm about ready to update my KK build thread on the classic pattern forum. but there are 2 build threads going on here. hmmmmm
Old 12-11-2008, 09:58 AM
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Default RE: Sig King Kobra

This is an old thread but thought i could get some tips here. After too many Kougars to remember, i finally decided to build a King Kobra. Ordered for Christmas so building will commence in a couple of weeks.

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