Author Topic: DGC Ka8b  (Read 138583 times)

Happy Days

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DGC Ka8b
« Reply #105 on: October 18, 2009, 22:28:21 PM »
This is obviously a big model Alan. When you come to launch it you’ll want to get it out into the lift and reasonably high as soon as possible.

I wonder if you might consider it a good idea to fit a hook to the under side and do what Lothar does. i.e. Launch off the slope using a piece of bungee. That would pretty much guarantee to get your model straight out into the lift with a high air speed, thereby giving you time to get the ‘feel’ of the plane before it might start to loose height if the trimming isn‘t right.

I think if I’d just spent umpteen hours of work on a plane of that size, that’s what I’d do.  I’d hate to see it go nose in, or tip stall on first launch. :cry:

Keith
Try not to run out of airspeed, altitude and ideas....... all at the same time.

Alan_Perse

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DGC Ka8b
« Reply #106 on: October 19, 2009, 10:23:04 AM »
If you were to launch a plane with a bungee and the trim was not right things could go pair shaped quite quickly as well. The K8 is not as big as you think it is. Not much bigger than any of Fred's machines or Joe's ASH26. All I need is a good wind almost directly onto the slope. That should do the trick, I hope. Anyway the K8 is not a speed machine. It's supposed to fly well at low speeds, at least I hope so. If it does crash I won't be too disappointed. Building it was a great learning experience. I have learned a lot of things that will make the next model I make even better.

Alan_Perse

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DGC Ka8b
« Reply #107 on: November 24, 2009, 21:28:37 PM »
Hi Lads. It's almost finished now. I have 99% of the lead installed in the nose. Man it took a LOT of lead to balance it. The K8's weight is approximately 5kg. Is that too heavy for a 1/4 scale glider with a 3.75m wingspan, Fred? All I have left to do is balance the wings and fix the sticking airbreaks. Here are some pics of what it looks like now.

Man it looks big






Here's a picture of my balancing devise

JohnPearson

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new glider
« Reply #108 on: November 24, 2009, 22:00:26 PM »
Hi Alan, now that's what I call a glider, great job she looks fantastic. I look forward to seeing this lady, take to the skies, soon I hope???

JohnP

haydenc

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DGC Ka8b
« Reply #109 on: November 24, 2009, 22:10:01 PM »
:clap:  :clap:  :clap:
Alan.
It looks fantastic.
Well done.
And the new reg as well.
It will take a lot of courage to launch that off the side of the hill.
When do you think it will fly.

Cha

Fred

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DGC Ka8b
« Reply #110 on: November 25, 2009, 08:42:43 AM »
Hey Alan,

Looking good !  :clap:
5kg seems ok to me. Most important is the wing loading. You certainly are between 50 and 60g/dm2, so still good ! And too light is not good too anyway !  :D
Education is important, but flying RC planes and gliders is importanter!

Alan_Perse

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DGC Ka8b
« Reply #111 on: November 25, 2009, 09:54:37 AM »
Thanks Lads. If everything goes according to plan I might try and fly her this Saturday at Mt Leinster. But thats weather permitting off course. I'll post a message on Friday to confirm if I will be there or not.

Fred: Thats a relief. I thought 5kg was too heavy. It feels quite heavy when I lift it. But your right, its the wing loading that counts. Thanks.

Peter

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DGC Ka8b
« Reply #112 on: November 26, 2009, 19:46:21 PM »
Great looking glider Alan - looks the business!  Well done.  I put a shed load of lead into the front of the B4 as well!  I guess these scale gliders are designd to have a person up front!

Alan_Perse

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DGC Ka8b
« Reply #113 on: November 26, 2009, 19:55:09 PM »
Thanks Peter. Hmmm, maybe someone should make a scale pilot from Lead. That would save having to put most of the lead in the nose.  :?:  :?:

Alan_Perse

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DGC Ka8b
« Reply #114 on: December 01, 2009, 17:47:41 PM »
Hi All. Here are some pics of my K8 at Mt Leinster. As some of you already know the first flight did not go quite according to plan and I crashed it. But the damage was minor and has already been repaired. I think I know what caused the problem, a stupid mistake by me when setting up the glider before launch.
 



Fred

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DGC Ka8b
« Reply #115 on: December 01, 2009, 18:19:43 PM »
Hey Alan,

Good to see her soon back in the air !  :D

So, what was the issue at the end ?  :?:  Decalage ?  :?:
Education is important, but flying RC planes and gliders is importanter!

Alan_Perse

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DGC Ka8b
« Reply #116 on: December 01, 2009, 18:35:02 PM »
Do you remember before launch you told me to put in some down trim, to stop a stall just in case it was tail heavy. Well I accidental put in up trim  :oops:  :oops:  :oops:  :!:  :!:  :!:. But I'm going to check the decalage just in case as well, and recheck the CG.

Alan_Perse

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DGC Ka8b
« Reply #117 on: March 03, 2010, 11:52:57 AM »
Hi All,

Just an update. It flies  :D  :D  :D  :D, finally. I have a very short video. Its not the best quality but it will do. Thanks for the launch Peter.

[youtube]http://www.youtube.com/v/71Pfmx6Dd9M[/youtube]

I got two flights in that day. But I did a little damage to it attempting a third launch. But it will be easy to fix. It broke in exactly the same places as the last time.

joe

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DGC Ka8b
« Reply #118 on: March 04, 2010, 19:54:10 PM »
Great to see you getting a few flights on the K8. Looking forward to seeing it in the air. After all that work it must be very satisfying to get it in the air.

Alan_Perse

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DGC Ka8b
« Reply #119 on: March 04, 2010, 20:26:04 PM »
Thanks Joe. Yea It was great to finally get it in the air. Very satisfying. Just need to tweak a few things such as the CG and decalage to get it flying right. When do you think you will get to finish your scale gliders?