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Old Jul 06, 2012, 07:12 PM
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It's usually the other way around - flaps down, elevator up, especially on a plane like the F-18, which is a tailed cropped delta.
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Old Jul 06, 2012, 07:20 PM
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If you use the rudders as an airbrake (deflect inward) like on the full size Super Hornet, the nose may pitch up as the vertical stabilizers are canted outwards.

With flaps deployed, the nose should drop based on the planform and short tail moment of the airframe, requiring a mix of up elevator.

Good luck on your experimenting.
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Old Jul 06, 2012, 07:56 PM
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Quote:
Originally Posted by fredmdbud View Post
It's usually the other way around - flaps down, elevator up, especially on a plane like the F-18, which is a tailed cropped delta.
Have you seen a real F-18 land on a Carrier? There is a lot going on with the wing control surfaces. That being said ,with this plane other than trying to be "Scale" it is not necessary to do Flaps.Rudder,Down Ailerons and the like. The plane does one thing well and that is land LOL!
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Old Jul 06, 2012, 08:08 PM
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Yes, I've seen videos of F/A-18's landing on a carrier, and even real ones landing at an airstrip (Blue Angels @ NAS Willow Grove). Here's a Swiss F/A-18C landing, notice the elevator deflections.

Swiss Air Force F/A-18 Landing at ILA Berlin Air Show 2010 (full HD) (1 min 3 sec)


Like I said earlier, fighters like the F/A-18 and the F-16 are basically tailed deltas. When flaps are deployed, they not only slow the plane and lower the speed at which stall occurs, they also impart a nose-down moment to the plane, requiring the elevators to compensate. Consider how far the flaps are from the center of gravity compared to conventional straight-wing and shallow sweep wings. Also explains why tail-less delta planes *don't* have flaps. When tail-less deltas deploy flaps, the ailerons dellect up to compensate, or employ canards to do the same.

I modified a Max Jet 64mm F-18 jet with flaps and ailerons, and when flaps were deployed, I had to use elevators to keep nose up. When I raised flaps, had to let up on the stick because that nose-down tendency dissapeared.
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Old Jul 06, 2012, 09:55 PM
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Thanks for sharing that, I would have got it wrong.

Shot a quick video a couple hours ago, but it's out of focus for the first minute
Stupid cell phone camera.
Anyway, put it on my you-tube because it was the first time my dad has ever seen a ducted fan jet and I want him to be able to see it again. I'm teaching him with a Nitroplanes "skytrainer" Cessna and my sims (FSone and Pheonix 4.0).

I was wrong a few pages back, my stock bird puts out around 630watts, not sure why I thought 550. Here is me handlaunching anyway and having a little fun. Very relaxing. I plan on getting daring with her now that I can fly next to my house (stupid useless landing gear). In another 20 flights or so I'll use a good camera and put on a show worth videoing assuming it's still flying.

Again sorry the video is blurry at the start for so long.

Exceed F-18 70mm EDF (3 min 15 sec)
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Old Jul 06, 2012, 11:22 PM
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Quote:
Originally Posted by MERLIN V16 View Post
Have you seen a real F-18 land on a Carrier? There is a lot going on with the wing control surfaces. That being said ,with this plane other than trying to be "Scale" it is not necessary to do Flaps.Rudder,Down Ailerons and the like. The plane does one thing well and that is land LOL!
Yes, this plane has good low-speed characteristics, and will do a nice, unpowered glide. Good stall recovery, too.

That being said, one problem would be space. It doesn't take much room to take-off, but landing could pose a problem if your runway is limited, just like on an aircraft carrier. You could do a slow, high-alpha crawl down to the ground, then level before landing, but you risk a tailstrike with the elevators, as well as pancaking with the landing gear. You could also implement slight spoilerons to cut some lift for a steeper glideslope, but again you'll tend to slam the ground with the wheels. Imagine all that on top of a narrow wheel track.

Forget about trying to fly "scale" and the fly-by-wire flight-computer-controlled wing surface movements - flaps are a pretty good option. And they're proven to work, too.
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Old Jul 07, 2012, 12:40 PM
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Originally Posted by Ispintechno View Post
Here is me handlaunching anyway and having a little fun. Very relaxing. I plan on getting daring with her now that I can fly next to my house (stupid useless landing gear). In another 20 flights or so I'll use a good camera and put on a show worth videoing assuming it's still flying.
Very nice video. Confidence is key, yup. Once it's up in the air and you know how it flies, the door's wide open.
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Old Jul 08, 2012, 01:17 PM
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Put some more flights yesterday and today. Also painted those sidewinders so now she is formally finished.
E
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Old Jul 08, 2012, 05:29 PM
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started to buy some stuff to test out for this plane. I am getting a used BL15 w/ the deltaV Fan (e-flite stuff) also i am getting the L2855 from HK for the Changesun 10 blade fan. There was a video of a guy who used two of them (L2855 and CS 10 blade) on a 737 and it had tests of his in the videos so it looks like that will work. I also saw someone using the bl15 (eflite) with the CS and there were doing that on 4s so i may test that too. Now i just need an ESC and i can start testing this stuff as it comes in.
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Old Jul 08, 2012, 08:41 PM
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Originally Posted by earaoz View Post
Put some more flights yesterday and today. Also painted those sidewinders so now she is formally finished.
E
Looking really nice! Awesome detailing, she must look the part in the air


I just bought a CS 10 blade fan with HET motor all cleaned up and balanced from Extreme RC in Australia. It's going into this bird once it arrives and I figure out a good ESC to use. Thinking a bigger Turnigy Plush 80amp as I already have the programming card and am very impressed with my 60amp one.

http://www.extremerc.com.au/estore/i...oducts_id=1101
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Old Jul 08, 2012, 08:58 PM
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Quote:
Originally Posted by xfatdannx View Post
started to buy some stuff to test out for this plane. I am getting a used BL15 w/ the deltaV Fan (e-flite stuff) also i am getting the L2855 from HK for the Changesun 10 blade fan. There was a video of a guy who used two of them (L2855 and CS 10 blade) on a 737 and it had tests of his in the videos so it looks like that will work. I also saw someone using the bl15 (eflite) with the CS and there were doing that on 4s so i may test that too. Now i just need an ESC and i can start testing this stuff as it comes in.
I hope you figure out a good combination with the CS fan, I've been drooling over it for a while now myself.
I've looked at the e-flite stuff, the Habu Delta-V, and it's an awesome set-up but sounds to darn screamy and irritating for my flying area. I'm pushing it with the Exceed set-up and a 6 blade hobby king combo in my F-4. Need to quiet it down as there is a quarter million other Canadians in my city.
For the frequency of my flying and the fact I normally fly WWII foamies that are nearly undetectable for noise, I don't get any complaints. But, the CS10 fan makes more sense for me than any other purchase in my situation still.
Plus the sound is a bit of a turn on. Not going to lie, it's not all noble on my end. Part boner.
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Old Jul 09, 2012, 12:36 AM
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My biggest worry is balancing. I read this thread on here how to do it with the accelerometer in any smart phone. I didnt pay for the software yet but maybe when i start running some tests we'll see. Either way i will let you know what i find. The only reason i got the eflite stuff, saw a guy use the bl15 w the cs10
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Old Jul 10, 2012, 04:41 PM
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Joined Jun 2011
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what are you guys doing to get this thing to roll down the runway without being so sensitive on the steering.... I find myself aborting takeoffs cuz it gets up to a speed and starts veering violently..... this thing is driving me nuts.... i am now using the fixed gear because 2of my 3 retracts quit working even before the first flight
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Old Jul 10, 2012, 04:47 PM
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How much slack is in the wire when the nosegear is extended? The wires don't have to be really tight, but too much play complicates steering.

You could also consider putting a rate gyro on the steering servo. I have one on my 64mm T-45, works pretty good once the bird gets rolling. The closer you can mount it to center of mass the better.
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Old Jul 10, 2012, 04:53 PM
Mankato MN
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I actually ditched the pull pull and added a pushrod and ball links...for the nose steering
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