Originally Posted by nickchud

Laddie: Lovely! That seems quite a small canard, are you using elevons? Or perhaps it's an all-moving canard?

Nick

PS I followed the link you gave us. There's quite a bit of discussion there about small canards. Clearly the moment is critical if you're going down to 5.5% of the main wing area, as you did. The Long EZ and Starship are much shorter than the Ascender, I think. Is it very sensitive to getting the CoG right?

Nick, the all moving canard is the elevator. The ailerons were left to be the ailerons.
Just for someone who is interested. The canards travel approximately 25 degrees in both directions. When the elevator stick is in neutral the canards are approximately at +5 to +8 degrees. So the canards moves to +30 degrees when giving full up and -20 degrees for full down.

That's really interesting. I had it in my mind that most wings stall when the AOA reaches about 10-15 degrees. So, can you notice that happening when you pull the full elevator up? It didn't seem that way in the video. Any ideas why not?

Nick

Laddie, Congrats on your Ascender! Did your video show the canard in a stall at one point? The model seemed rather fast which would allow a smaller canard than on a slower one IMO. Also, with a short nose and lots of wing sweep, it would seem that it could fly well with the CG back near the main wing.
Charles

The more little the aspect ratio of the canard, the more induced alpha it will have, adding to the geometric AoA before it stalls.

A little AR can also give a rather soft stall, that might escape ones notice.

biber

Nick. I do have these large throws on the canard surfaces, but I do not think I ever move them to extremes. I am pretty sure I never used full down on the canards. Full up, maybe but not on purpose to find out what will happen. Next time when I will go flying, I will try to move them to extremes. I know that when taking off or coming for the landing, I did not have to give the canards much up. I am enclosing short video taken same day as the first one. I shows takeoff and landing.

Charles, the canard is small but it seem to be sufficient to keep the nose up at the slow speed. It can be seen in second video. I am not aeronautical engineer, but I think reason the canard can hold the nose up is that the C/G is already as far back as possible for this model.
I will never move the C/G back a fraction of the inch. I have been there and it is not pretty.
http://www.youtube.com/results?searc...2C22%2C28&sa=X

May I ask where you placed your CG? Sorry if you've already mentioned it, but there are something like 374 pages to this thread, and I guess I'm a bit lazy.

My Curtiss P-55 Ascender has an enlarged canard because I was concerned about stability when I built mine. However, it is a full-flying canard also.
I haven't flown it yet because my steering is fixed, and the powerful engine tends to torque-steer my plane, so it's difficult to get it to track straight.
I wish I made my landing gear steerable like you had. I might have to bungie-launch my P-55.

Very nice job, and nice flight too!

Laddie Mikulasko the delta-wing maven? This appears to be a well-behaved "Ascender"! Makes me want to get mine finished - built from modified Jack Bale plans. Are all the construction details posted on "the other site"?
;-)
PJ

Originally Posted by builderdude

May I ask where you placed your CG? Sorry if you've already mentioned it, but there are something like 374 pages to this thread, and I guess I'm a bit lazy.

My Curtiss P-55 Ascender has an enlarged canard because I was concerned about stability when I built mine. However, it is a full-flying canard also.
I haven't flown it yet because my steering is fixed, and the powerful engine tends to torque-steer my plane, so it's difficult to get it to track straight.
I wish I made my landing gear steerable like you had. I might have to bungie-launch my P-55.

Very nice job, and nice flight too!

I am enclosing the drawing showing the placement of the CG in my model in inches. For your test flight I would place the CG at 7”proportionaly to the size of your model. It is too bad that you do not have steering on yours. To use bungee-launch on the first flight is too risky.
Anyway, good luck.

Guys:
Canard planes with spherical configuration,FYI
Regards
Sam
PICT0517PICT0550PICT0657

PICT0526 (1 min 4 sec)

PICT0670 (0 min 38 sec)

To use bungee-launch on the first flight is too risky.

Bungee launch isn't too bad...I was following instructions from MichaelGHammer:

Things I found out (the hard way) about the catapult: Keep the length of the string from the ring (the one that attaches to the hook on the plane) to the release ring to a minimum. The release mechanism should be underneath the model. Not behind it. This way the string can´t get tangled up with the pusher props or the vertical stabs. Use an old model to help adjust the launch angle (should be fairly flat, about 5-10 degrees) and the bungee tension.

I was using fairly lightweight bungee, not as fierce as luggage cord. 30ft of 3/8" cord from "Bungee Central" in LA. I think the AUW of this Starship is about 5lbs.

Starship flying (0 min 44 sec)

Originally Posted by LADDIE

I am enclosing the drawing showing the placement of the CG in my model in inches. For your test flight I would place the CG at 7”proportionaly to the size of your model. It is too bad that you do not have steering on yours. To use bungee-launch on the first flight is too risky.
Anyway, good luck.

Yours is a different version of the Ascender than mine. However, the CG shouldn't be any different. Here is a pic of my Ascender. It's the military version, and my CG is approximately the same as yours. My tail fins on the fuselage are different, I made mine stock and made the scoops functional. The exhaust stacks are also functional, and serve to move cooling air through the compartment where the motor and ESC are.

You'll notice my Canard is larger. I used some old rubber-powered Stahl plans, and modified them for a 32" wingspan, with strengthening throughout. I've got a 1400 mah inrunner and a 3-blade 7x4 pusher prop. I kept my canard the same scale as the original stahl plans and build a glider to experiment with CG and degree of static angle on the canard. It flies great, and the cats love it too, unfortunately. Here's both:







I've noticed on yours, the placement of the fins on the wing is more inboard than with mine. I've got my rudders on a servo, but it's not enough throw to make much of a difference. And that's because my wing was too thin out by the rudders to put servos there, and there's too much slop through the bellcrank linkages. So all my turns will have to be aileron turns. I wonder if I could alter my front gear for steering ability. I'll have to think about that. My gear is removeable though, and it weighs 5 oz less without the gear. (Tall grass landing, of course).

I know what you mean about bungie launching being risky, but right now, it's the only way I can do it. I could probably make a rail launch system with the wing supported on the rails so that when it comes off of it, it's tracking straight. I've seen a few like that on YouTube.
My glider glides great, but it is definitely sensitive to a proper, straight launch.

Here's NASM's XP-55 nearing completion of restoration at the Kalamazoo, MI "Airzoo" in 2007. It had been mothballed at the Garber Facility in Silver Hill, MD for many years. Note OD upper and sky-blue under colors.

PJ

Hi guys, sorry to butt in on this thread but this thread seems to be the canard internet guru place and I need help. I have a nitroplanes rutan canard arf that I got a year back from fleabay at a super low price due to a cracked canopy, I bought it because I thought it was a amazing looking aircraft.

Anyway after getting the model and doing some research I found that many pilots have had poor first flights with this model and I am not sure if apart from the one that was on youtube any have survived their first flight, due to this and my one year flying skills I shelfed it.

Now a year later and with another years better flying skills I think it is time to fly this bird, so if anyone has experience with this plane and the cog in particular i would appreciate your advise on making this interesting plane fly.

I expect this to end in failure but will post my endeavours here.

raydar, Is it the 0.46 or the electric Voyager?
Charles

Originally Posted by pjwright

Here's NASM's XP-55 nearing completion of restoration at the Kalamazoo, MI "Airzoo" in 2007. It had been mothballed at the Garber Facility in Silver Hill, MD for many years. Note OD upper and sky-blue under colors.

PJ

Yes sir, OD green it is. I just didn't feel like painting mine like that. I imagined what it would look like with a polished aluminum finish instead.