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General control line discussion => Open Forum => Topic started by: Allen Eshleman on March 16, 2015, 02:43:01 PM

Title: First Flights of the Spring - Akromaster
Post by: Allen Eshleman on March 16, 2015, 02:43:01 PM
I did my first flights of the Spring today.

Three flights on a McCoy 19 powered Akromaster.  First time with the engine.  Got the needle closer with each flight.  Also, for the final flight I changed from a 9/4 APC to a 9/5 APC. The combination of more rpm and more pitch made for a much better last flight.  Still - it's a terrible flying plane.   It was fun.

It doesn't want to stay on the end of the lines.  It already has two extra washers in the front for off set and a slight off set on the rudder.

Ideas I have for improvement -

               1.    9/6 prop
               2.    Fresh fuel - this got a few drops of rain in it one day
               3.    Move the leadouts back - it doesn't have adjustable leadouts
               4.    Switching to an Enya 15 III.  I haven't tried it yet -  would lighten the plane.
           
Any ideas? 

Thanks ahead of time.
Title: Re: First Flights of the Spring - Akromaster
Post by: Dave_Trible on March 16, 2015, 03:20:34 PM
I doubt you have a power problem.  I'd look at your lines-should be .012 x about 52' for that combo.  Sounds like what you have are too long and or heavy.  Also look for warps in the wing and correct them if found.  Also did you forget the tip weight?

Dave
Title: Re: First Flights of the Spring - Akromaster
Post by: frank mccune on March 16, 2015, 05:16:43 PM
    My bet is it is nose heavy with the McCoy .19.  I have flown them with the Fox .15 baffle engine and they flew very well on .012x52' lines.  This plane only has 250 sq. in. and I think that a T.D. .09 will fly it very well. Try a lighter engine!

                                                                Good luck,

                                                                Frank McCune

     
Title: Re: First Flights of the Spring - Akromaster
Post by: Allen Eshleman on March 16, 2015, 08:58:05 PM
I am thinking about putting on a lighter engine.  However, I did lengthen the wings by an extra rib and the tail by an inch.  However, if I were to give it a lighter engine I could remove the weight in the back to counter balance the heavy McCoy.
Title: Re: First Flights of the Spring - Akromaster
Post by: john gunn on March 17, 2015, 04:01:02 AM
I fly one with an ENYA 20, no muffler on 58 ft 15k lines it is a fun event,no flaps, the next one will have flaps.  I use a 9-4 prop
Title: Re: First Flights of the Spring - Akromaster
Post by: Dave_Trible on March 17, 2015, 09:54:46 AM
A nose-heavy airplane produces MORE line tension*. Might try removing the tail weight and trying it.  Don't worry to much about the CG for the  moment.  This will mostly just slow down the control response.  You can deal more with that  going forward.  Adding tail weight is usually a bad sign.  Try it without first.  Then you can work the engine and tank back further,  use lighter wheels, increase handle line spacing or other means to improve the turn rate if you want too.

Dave

* In level flight and below about 60 degrees of elevation.  It starts working against you above that.  I don't think we are worrying about vertical maneuvers in this case.
Title: Re: First Flights of the Spring - Akromaster
Post by: Paul Smith on March 17, 2015, 12:32:16 PM
I have one with an OS LA 15 and the wing stretched as most builders do.

It doesn't fly all that great, but it flys.

Title: Re: First Flights of the Spring - Akromaster
Post by: DanielGelinas on March 17, 2015, 06:02:26 PM
Hi Allen,
Do you have a fox 15x slantplug on hand? The plane balances wonderfully with this engine. I had an os10la on mine and changed it for the fox 15. What a difference it makes (-three ounces!).
Daniel
Title: Re: First Flights of the Spring - Akromaster
Post by: Randy Ryan on March 18, 2015, 07:28:33 AM
I fly mine on a PAW .09, it will fly the entire pattern fairly repectably. A McCoy .19 is pretty hefty for that little airplane.
Title: Re: First Flights of the Spring - Akromaster
Post by: john e. holliday on March 18, 2015, 10:42:41 AM
My Daughter flew hers with a Medallion .15 and it flew great.   Hers is box stock.
Title: Re: First Flights of the Spring - Akromaster
Post by: Allen Eshleman on March 18, 2015, 03:20:22 PM
Thanks for the great ideas.

I am first going to try again with less weight behind or more on the front.

Once I get the Enya running,  I may go to it.  I would love to have a pattern plane this size.  Mine has flaps.  I was hoping for a pattern plane that would use a lot less fuel than a "40".  Waiting for free day and good weather to co-incide again.  It's supposed to snow here on Friday and today is very windy.  Should get up to "47" tomorrow.

Title: Re: First Flights of the Spring - Akromaster
Post by: Randy Ryan on March 18, 2015, 04:58:10 PM
My Daughter flew hers with a Medallion .15 and it flew great.   Hers is box stock.


Yes! A Medallion .15 would be about perfect.
Title: Re: First Flights of the Spring - Akromaster
Post by: Randy Ryan on March 18, 2015, 04:59:56 PM
Thanks for the great ideas.

I am first going to try again with less weight behind or more on the front.

Once I get the Enya running,  I may go to it.  I would love to have a pattern plane this size.  Mine has flaps.  I was hoping for a pattern plane that would use a lot less fuel than a "40".  Waiting for free day and good weather to co-incide again.  It's supposed to snow here on Friday and today is very windy.  Should get up to "47" tomorrow.




Properly trimmed the Acromaster will do a respectable pattern and its fun! Noseheavy you'll have a hard time getting it to turn well enough, especially  on square bottoms.
Title: Re: First Flights of the Spring - Akromaster
Post by: John Paris on March 18, 2015, 08:26:27 PM
Randy,
You should describe how it fairs under electric power (aka Corey).  I was impressed how he hung in there during the contest and how he has hung in there overall.  Grace has one with Enya 15 power that she says is possessed.  I have a couple more that I plan on building with different power plants and hope for some good results.  It is a decent airplane in need of an appropriate power plant.
John
Title: Re: First Flights of the Spring - Akromaster
Post by: Randy Ryan on March 19, 2015, 05:52:57 AM
Randy,
You should describe how it fairs under electric power (aka Corey).  I was impressed how he hung in there during the contest and how he has hung in there overall.  Grace has one with Enya 15 power that she says is possessed.  I have a couple more that I plan on building with different power plants and hope for some good results.  It is a decent airplane in need of an appropriate power plant.
John


Well, I can't really say much except it did seem to hang out well. Without flying it though its hard to say, so I'll tell a different story. One day I was at the field flying the AM, I'd finally got it proped fairly well and had pumped out about 4 patterns and flying the fifth. Just after takeoff I noticed and car coming in and part in the CL area, it was Tom Polk and Keith McCrary. I landed and went to say hi and Tom said something like "thanks for making me look like an idiot" A asked why and it seems he and Keith were talking about the AM on their way over and Tom told him it was not capable of the pattern. Tom then said "Then I pull in here and see you flying it like that and all my credibility is gone!!!"
Title: Re: First Flights of the Spring - Akromaster
Post by: YakNine on March 20, 2015, 07:56:31 AM
I have been flying the heck out of my daughters buster with an old 15x on it and can't wait to try it on the am . I have been using it with an RSM St needle and its a sweet little engine the threads were really loose on the fox needle and very inconsistent. T.J.