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Flyer03/02/2016 22:17:13
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617 forum posts
108 photos

Just spread out the plan of the X29A acroos the dining room table (SWMBO is out), and it looks big. The throuble is, its only approx 1/9th scale. I was hoping to buiild it to 1/7th scale. This should allow me to incorporate working canards and also use flaps, (which were not on original plan). Is there any truth that a larger PSS aircraft will follow the flight characteristics of the original?

Picking up balsa and lite ply on Friday to start cutting out pieces in the next few weeks.

Any advice welcome.

Cheers

Ade

Andy Meade03/02/2016 23:00:07
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2772 forum posts
717 photos

Big planes are just a pain to rig, a pain to build, need expensive servos, more batteries to keep big servos happy, need more covering, require more cockpit work to make it worthwhile, and are a pain to launch.

Go for it I love oddball planes - if it works at the larger scale, lend me your plan

Flyer03/02/2016 23:02:45
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617 forum posts
108 photos

As a matter of interest Andy, whats the dimensions on your A10? I may have to bribe a launcher wiv a bacon butty or two..... wink 2

Andy Meade04/02/2016 10:13:03
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2772 forum posts
717 photos

Wingspan is 110", I think the length is the same if not a bit more. 40lbs AUW.

Flyer04/02/2016 10:25:11
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617 forum posts
108 photos

Thanks Andy,

At 1/7th Scale the Fuselage will be just under 82 inches, with a wingspan of 46 inches. At this size I will have the wings removable, breaking at the fuselage , with as large a wing joiner, and will look at having a join in the fuselage just in front of the leading edge. This will enable the canard to be operated as designed, and I think I have worked out the bearing method for that. The problem may be that the wing joiner may have to be carbon, as it will be a fair way behind the Cof G. But this may be helped by the extra weight ahead of the C of G with the working canards. Of course, useful weight can be used by putting the battery in the nose.

I should also try and incorporate flaps, as the original plan design only shows ailerons and elevators (rear part of the canards were hinged). I guess that flaps should assist my landings (if it indeed survives the launch).

The more I look at it, the more I want to build it to 1/7th scale, so I apologise now for the endless stupid questions I will be asking.

thanks so far for the help.

Flyer04/02/2016 10:25:11
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617 forum posts
108 photos

Thanks Andy,

At 1/7th Scale the Fuselage will be just under 82 inches, with a wingspan of 46 inches. At this size I will have the wings removable, breaking at the fuselage , with as large a wing joiner, and will look at having a join in the fuselage just in front of the leading edge. This will enable the canard to be operated as designed, and I think I have worked out the bearing method for that. The problem may be that the wing joiner may have to be carbon, as it will be a fair way behind the Cof G. But this may be helped by the extra weight ahead of the C of G with the working canards. Of course, useful weight can be used by putting the battery in the nose.

I should also try and incorporate flaps, as the original plan design only shows ailerons and elevators (rear part of the canards were hinged). I guess that flaps should assist my landings (if it indeed survives the launch).

The more I look at it, the more I want to build it to 1/7th scale, so I apologise now for the endless stupid questions I will be asking.

thanks so far for the help.

Andy Meade04/02/2016 10:32:55
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2772 forum posts
717 photos

Always ask questions! To be honest, I've never had a problem balancing a canard - the noses are so long you rarely (in fact, never, in my case) need to have the battery all the way up the front. Are you going for the landing flaps that are just either side of the fuselage near the jet pipe?

You can really play tunes with canard control systems, and the added flaps will be a great addition. I've used elevons on the rear wing and the canard as a landing flap, as well as normal ailerons on the rear wing plus canard as the elevator - even on the same model! With the Viggen I also have the ability to use the canard surfaces mixed as roll control too, but not tried it yet.

Fighteraces do some very nice wing joiners with phenolic tube if you don't fancy carbon.

I'm looking forward to it already! cool

Edited By Andy Meade on 04/02/2016 10:34:06

Flyer04/02/2016 10:38:33
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617 forum posts
108 photos

If I build the 1/7th scale. i do want to use the full size designed controls. I really want experiment with mixing the canards with the flaps/ elevons etc. May need two black bin bags with this one,,,,,,

Andy Meade04/02/2016 10:42:12
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2772 forum posts
717 photos

Don't be so negative! She'll be fine - the model has a proven track record as a sloper, so nothing to worry about in reality. For the first flights it would be wise to fly her as basic as possible, then switch in mixes to frighten yourself when required!

Dane Crosby04/02/2016 10:52:36
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245 forum posts
23 photos

The larger she is, aerolastic distortion (giving divergent pitch up) becomes more apparent. Make the wings strong !!

Andy Meade04/02/2016 11:48:16
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2772 forum posts
717 photos

Ade - are you going for a foam wing?

Flyer04/02/2016 11:58:06
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617 forum posts
108 photos
Posted by Andy Meade on 04/02/2016 11:48:16:

Ade - are you going for a foam wing?

Nope, I'm looking at built up, using spruce spars and carbon tows to strengthen wing, fully sheeted then light glass cloth over the top. I've also seen the reports that the full size wing distorted, but I'm hoping that if I can make the wing stiff enough it wont be a problem at this size. I'll be using the phenolic tube and ali tube joiner too. I'm sketching out the design now to see the layout of the tubes etc, to ensure that it's quick to rig (although it may take longer to make). The built up wing should be lighter than foam, and by being strengthened in the right places, should avoid the type's tendency to diverge. Also, the glass finish should help with 'normal' use.

Andy Meade04/02/2016 11:59:42
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2772 forum posts
717 photos

That sounds like it should be plenty strong enough, especially at 46" span yes

John A H04/02/2016 22:13:49
138 forum posts
173 photos

Assuming it's the Malcolm Saunders plan you are using I have the July 1986 RCM&E with the build and design article in. If you want it PM me with your e-mail address.

Flyer05/02/2016 10:07:12
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617 forum posts
108 photos
Posted by John A H on 04/02/2016 22:13:49:

Assuming it's the Malcolm Saunders plan you are using I have the July 1986 RCM&E with the build and design article in. If you want it PM me with your e-mail address.

Thanks John, pm sent

John A H06/02/2016 09:38:01
138 forum posts
173 photos

E-mail on it's way. J

Just noticed that the Chas Gardiner "from up here" section in that copy of the magazine actually has an article "Power Scale Soarers get Organised" that mentions that Alan Hulme is forming a PSS Association. Fits in rather well with this year been the 30th anniversary.

Mark Kettle 124/06/2017 13:45:33
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2544 forum posts
1568 photos

Video watch at times - 0.00 > 2.24 - 5.40 > 10.08 & 12.46 > 14.20

X29 made from Flitetest foam .

Mark Kettle 106/07/2017 08:40:57
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2544 forum posts
1568 photos
X-29
Forward Swept Wing Test Pilot Kurt Schroeder discusses program history and his experience flying the experimental aircraft.
Mark Kettle 119/09/2017 06:20:22
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2544 forum posts
1568 photos

Ade - Flyer,

To follow on, Flitetest have finalised their X29 design with this video.

By the way these kits will be available from Gliders in Newark UK.
Flyer19/09/2017 07:21:24
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617 forum posts
108 photos

Cheers Mark,

That looks very interesting. I'll give it a shot when they get one in stock. Be useful to fly one to get used to the profile in the air.

Cheers

Ade

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