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General control line discussion => Open Forum => Topic started by: Allen Eshleman on July 12, 2013, 08:02:00 PM

Title: Flapped Akro, my New ride
Post by: Allen Eshleman on July 12, 2013, 08:02:00 PM
Well, after about two years it is finished.  This is the Akromaster I started building a long time ago.  My brother helped me finish.  It has fully functioning flaps,  McCoy 19 (at least for now).   Finish is Kolar Kote which worked well except for the transparent purple which I had to sandwich between tow layers of the solid colors.  Haven't flown it yet.   I can't show it yet - don't remember how to insert pictures.  I'm going on a search.  I just downloaded Irfan View but forgot how it works.  I'll be back.
Title: Re: Flapped Akro, my New ride
Post by: RknRusty on July 12, 2013, 09:10:19 PM
Hosting your pictures on Photobucket.com is easy and it doesn't matter how big they are. Then you just copy the links for either thumbnails or full size and paste them in your post.
Rusty
Title: Re: Flapped Akro, my New ride
Post by: Allen Eshleman on July 13, 2013, 03:50:38 AM
I couldn't remember how to post pictures but downloaded IrfanView and finally got it figured out.  
Title: Re: Flapped Akro, my New ride
Post by: Allen Eshleman on July 13, 2013, 03:52:23 AM
A few more
Title: Re: Flapped Akro, my New ride
Post by: Allen Eshleman on July 13, 2013, 03:55:31 AM
Though the colors may not appear accurately, the bottom color is gray.  I decided to go without the canopy.   The fuselage is an extra inch long in the tail and with the wings I used all the material sent by Sig which means they are an inch or two longer than noted on the plans.  I hope to fly it today.
Title: Re: Flapped Akro, my New ride
Post by: RknRusty on July 13, 2013, 07:50:31 AM
Looks good, Allen. We look forward to your flight report.
Title: Re: Flapped Akro, my New ride
Post by: john e. holliday on July 13, 2013, 08:35:19 AM
Looks great and should fly great.
Title: Re: Flapped Akro, my New ride
Post by: Allen Eshleman on July 13, 2013, 09:37:33 AM
Help,

First Flight - terrible -  I had to hang on the up line to keep from crashing and I finally did.  Thankfully, only problems, tank came off and the APC 9/5 propeller broke.  Plane is intact.

What kind of trim does this need?   Is this nose heavy or tail heavy?
Title: Re: Flapped Akro, my New ride
Post by: john e. holliday on July 13, 2013, 01:08:15 PM
Check to see if all surfaces are aligned as well as the power plant.   Also did you center controls before launch? LL~ LL~  Then again you may have had a clip hang up on you.   So many things that could have gone wrong.   Better luck on next flight.
Title: Re: Flapped Akro, my New ride
Post by: Allen Eshleman on July 13, 2013, 02:03:40 PM
The surfaces are aligned well.  I am thinking about the clips.  I do know that after flight, I realized that I had never closed them.  Would extreme balance problems either nose heavy or tail heavy cause this?    Very little control and and had to ride the up line.  I think I will make it a separate post.
Title: Re: Flapped Akro, my New ride
Post by: Steve Helmick on July 13, 2013, 02:26:45 PM
The surfaces are aligned well.  I am thinking about the clips.  I do know that after flight, I realized that I had never closed them.  Would extreme balance problems either nose heavy or tail heavy cause this?    Very little control and and had to ride the up line.  I think I will make it a separate post.

If the CG is located where the plans show, I would expect that the clips were tangled or the pushrod is flexing very badly. If you can eliminate the CG and pushrod, then it's the clips. The extended tail moment should allow a more aft CG, but probably not more than 1/4". Try the 9-4 APC on your Mac .19. McCoy NV's break easily, so be prepared. I would suggest changing to a different brand NV Assy.  H^^ Steve 
Title: Re: Flapped Akro, my New ride
Post by: Allen Eshleman on July 13, 2013, 03:02:02 PM
I'm going to try again.  The CG is right where it's supposed to be.   
Title: Re: Flapped Akro, my New ride
Post by: Tim Wescott on July 13, 2013, 03:10:20 PM
If the CG is located where the plans show, I would expect that the clips were tangled or the pushrod is flexing very badly.

Allen, looking at your left side view of the plane, not only do you not have a support in the middle of the elevator pushrod, but you've got a z-bend in it.  You're pretty much guaranteed that when you pull up on the thing the pushrod will flex.

Did the kit not call out a push rod support on the fuselage?  You should have gotten a little "L" shaped piece of nylon or steel sheet with holes at each end, and directions to thread the pushrod through it and mount it on the fuselage.

You should either mount the kit piece, or you should bend a "U" shaped piece of music wire and glue it into the fuselage to hold the pushrod steady.
Title: Re: Flapped Akro, my New ride
Post by: Balsa Butcher on July 13, 2013, 03:16:18 PM
I would also switch the position of the bellcrank/flap pushrod on the flap horn to the top hole with the flap/elevator pushrod below it. This is the way most modern stunters are setup and it may help. Oh, add a canopy, without one the pilot cannot see where he is going. 8)