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Post  944_Jim Sat Jul 17, 2021 2:57 pm

Good afternoon, Gents,

This is a build thread instigated by this one Cool :
https://www.coxengineforum.com/t3652p125-sig-akromaster-build

My humble entry to larger than 1/2A...unless you count my Big Mig .074 x 2 BHM Mossie. Well, I need to re-phrase that.

Ok,
My humble entry to larger than 1/2A sport flying.
My goal is to learn the OTS pattern with a plane that I can make several of in short order. I need to weigh each of my prospective engines, with and without muffler, and select the one closest in weight to the Fox .15 all the old threads mention. I may consider sleeving venturies down in size to slow particular engines down.

But for now...balsa dust flies, and R1 gets repaired. The glue line is visible only because the scab came from a different end of the same "short edge."
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Post  Ken Cook Sat Jul 17, 2021 4:05 pm

Jim, I'm a bit puzzled on what your trying to accomplish. I have to ask, why learn the OTS pattern on a plane that's not a OTS plane? The other is that the PAMPA pattern offers more maneuvers not too mention in my opinion is easier to learn. The OTS pattern was designed for planes not capable of flying very well. In other words, it was the best maneuvers that could be offered for the planes of the period.

If you can fly inverted, you already know how to fly ANY pattern. This is all you need to know. From there it's understanding where to place neutral in your hand and use your arm.

The next hurdle I see is learning to fly a pattern on a .15 size plane. They fly too fast to learn how to fly the pattern for a beginner wanting to learn. This means that for you to refine the maneuver to look like it's supposed becomes a difficult task. Even with coaching, the plane is flying too fast, twitching all over which results in over controlling and stalling to try and recover at times.


A Fox .15 X is fast. A Enya .15 even though more period correct is also fast for this plane. However, they can be made to work but you need to realize that using 8" props on these planes are going to do nothing but offer you headache and heartbreak if you don't let them turn up.

Your .074 would make a good choice as it offers darn near the power of a FP.10. Ideally, the FP .10 makes a excellent modern choice for a Akromaster. You said you have a Cox Medallion .15 which also works well. Unfortunately, plugs are $$$$$$$$, noise is another unless it's not a problem for you. The Medallion isn't a modern .15 but it does well on this plane .


Adding tail weight to this plane isn't a huge issue, I've had as much as 1 oz. on the tail of this plane. Just keep in mind that paint is heavy and this plane will do far superior if you just cover the wings in clear and paint the fuse if desired. There's absolutely no reason to finish a plane when your trying to learn any pattern. This is a waste of time and effort. The main thing is to get back in the air as quickly as possible. Therefore, building two of these are more important than trying to work on redesigning and figuring out which engine to use. Pick a engine, make two planes and go fly it.



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Post  944_Jim Sat Jul 17, 2021 4:33 pm

Ken,

I understand what you are saying. I'll just say I like some planes, I don't like others, and I'm not athletic by any stretch...and while not as old as some some, I'm broken enough that the OTS pattern is going to be an achievement.

I did loop and fly inverted as a kid. I suspect I will do that again soon, and then add reverse wing-overs for a bit of glitter/glam. I will doubtfully see a cloverleaf anywhere near a circle, unless it is breakfast time and I have a box of Lucky Charms. V-8s would be "bonus time," and H-8s would be a big grin. I'd even settle for a recognizable Lazy-8!

But for now, I need a plane I can mass-produce and store, so I don't build attractive models to be bashed into concrete for no better reason than "I'm bored and wanted to try [insert stunt]." That's what killed the Scientific P-40.

I'll.just about try anything once...twice if I like it. If I "graduate" out of OTS, then I'll continue trying/trashing trainers.
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Post  Ken Cook Sat Jul 17, 2021 6:08 pm

Are you just trying to fly some of the maneuvers or actually trying the pattern in it's order? Lazy eights in my opinion is a good start. You can fly a entire tank without ever even turning around right in front of you. Fly large inside and outside loops repetitively. This builds confidence not too mention your training your mind and hands to react as the plane changes altitude and direction. Another reason is that once the plane is coming around for it's opposing loop, the plane is inverted for a little distance. This is when one easily learns to offer neutral elevator and it will continue flying inverted. The problem is that your mind needs to coordinate with your hands and understand up is now down and vice versa.

A cloverleaf isn't a part of the OTS pattern but it's probably in my opinion one of the easiest maneuvers to fly. Your selling yourself short thinking you can't do one. You have to understand that when your in the circle, maneuvers are not supposed to look like a clover out in front of you or from the outside of the circle. A cloverleaf is a inside loop, a outside loop, another outside loop, a inside loop and out through the top of the circle. Nothing difficult about this at all. What one needs to know is when to enter these loops. This also means it's not done within a 1/4 of your flying circle, you can use the entire circle if you need to and make the maneuvers large. Making the large makes them smooth. Smooth means your not bleeding off speed. You need to leave enough distance between them so that your not strangling the plane by offering full up or down. When you do this, the plane totally stalls and speed bleeds off and the inevitable happens.


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Post  Ken Cook Sun Jul 18, 2021 5:56 am

Whatever happened with the UKIE? This is the plane to learn on. A very timid flyer with simple construction and it can take a ground pounding provided it's on grass.
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Post  Ken Cook Sun Jul 18, 2021 6:00 am

Whatever happened with the UKIE? This is the plane to learn on. A very timid flyer with simple construction and it can take a ground pounding provided it's on grass. If it does break, your back in business in minutes. Rusty crashed his at Huntersville and my son and I had him back in the air within 20 minutes with 5 min epoxy. He broke the fuse, the wing and tail. Popsicle sticks, clear packing tape and Rusty flew his 2nd official flight. Foam is wonderful, you can splice it back together, epoxy it, dowel it etc.
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Post  944_Jim Sun Jul 18, 2021 8:59 am

@Ken Cook wrote:What one needs to know is when to enter these loops. This also means it's not done within a 1/4 of your flying circle, you can use the entire circle if you need to and make the maneuvers large. Making the large makes them smooth. Smooth means your not bleeding off speed.  You need to leave enough distance between them so that your not strangling the plane by offering full up or down

Ken,
This is the first time it's been suggested to me that the events/stunts can occupy the entire circle (besides "fly stunts downwind for the longevity of the plane"). I've never been to a contest, and have only seen some video (YouTube). Because those videos showed the pilot in front of judges with the plane on the otherside , I always assumed the judges positioned themselves upwind to observe the downwind quarter of the circle...and so I assumed that is where stunts occured for competition.
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Post  Ken Cook Sun Jul 18, 2021 11:26 am

You can do anything you want in the circle. Yes, most stunts are downwind with the exception of the wingover. I suggested to you what I said based on the fact that your learning and not being judged. Now if your goal is to fly in front of a judge (Which wasn't mentioned) , judges don't judge on where you do your maneuvers, they judge on height, size, corners and intersections and overall appearance. So if all of your maneuvers are in the eyes of the judge and the wind shifts, you do what you need to do. If you choose to do your maneuvers completely opposite of where you have been doing them, the only harm you do is that the judges can't judge it correctly. Just for the record YOU instruct the judges where you want to do your maneuvers. If you point to them and tell them to move, that's what they're supposed to do.

                 When I suggested using the entire circle, it wasn't stated to be done in front of judges. It was also speaking figuratively which means that you still don't need to do the maneuver directly in front of you. Use as much room as you need to complete it as to not slow the plane down.  I stated that you can learn maneuvers easier by using as much room as needed. Judges are not going to penalize you for making large maneuvers as a beginner or intermediate. If all of your maneuvers are the same size all being large, your going to do just fine. If one is small and the other is huge, that's another issue.

        A common mistake for someone just learning maneuvers is to make them too small and tight. I sound like a broken record, smooth transitions means keeping the speed up. Keeping the speed up means proper line tension and smoothness through the maneuver. If you pull full up in a panic situation, the plane bleeds off speed so fast and drops.
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Post  Ken Cook Sun Jul 18, 2021 12:14 pm

Jim, in addition working on inversion is the most important and hardest maneuver in any of the patterns. My statement was totally accurate, if you can fly inverted, you can fly ANY of the pattern.
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Post  Yabby Sun Jul 18, 2021 4:52 pm

Hi Jim and Ken,

I think I and many others are where you are Jim. As kids we could fly up a storm! Lol. Im returning to the hobby/sport at 60 and have found loops and wingovers all very simple but getting lazy eights working not so simple. I agree that getting flying inverted lots and really naturally again is one of the keys. Retraining the mind, but such that control remains smooth. Being smooth I believe is very very key, when you are smooth you seem to have more time, do you becomes smooth because you are better? maybe. Concentration and the zone has a lot to do with being smooth and understanding how your plane reacts to certain things is important. I know when I raced Grand Prix TZ bikes in Australia, when I was smooth I went faster, but when I was ragged I went slower. The trick though is going past the ragged edge where your concentration and reflexes are struggling and your in the red zone and then making that smooth. Then your going even faster than most but you are what you call smooth. When young I used to not understand how others could not drift two wheels into a corner at over 100mph as I had come to the point where my mind, reflexes, concentration, understanding of the bike and the track could all work together to pull it off. But I never understood why everyone else couldn't do it. Another factor is that you will not find the edges and limits without crashing. That is a simple fact. I only knew how far my slicks could lean me over or how hard I could push my front wheel into a corner by crashing sometimes. Even the best ever crashed, but as you get better the crashes become less frequent as you start to be able to feel and recognise the slightest early signs of being on the edge of adhesion. But from every crash, go back into your mind, replay it and look at what you did and what happened and what maybe you could have done different and learn from it. Dont blame the plane or the wind etc. or even an engine cut-out. Its up to you to manage the situation. Visualization techniques are great when chilled out, practice in your mind, really visualizing your maneuvers including what you will be doing with you control arm/hand. Practice lots!! but dont do the same stuff all the time!! add in some fun climbs that flip into vertical dives and do childish things again like trying to fly as fast and low as you can. That will get you concentration and really fine plane control to improve. I have found flying on stupidly windy days great for getting my reflexes and control back again. Days when you can climb into the wind and almost stall and your plane just wants to flip over or come back at you or tumble. They are great for learning control. I find those days are like when I would race or practice for racing in the pouring rain, you were constantly every second fighting to keep control and learnt heaps.

But just cos you could do it once, and now much older, it may not be so simple, I could not possibly ride a TZ Grand Prix bike the way I once did. My reflexes, strength, co-ordination, sight, hearing, concentration have all waned somewhat. But what you can do, is like me have an absolute blast trying and learning to fly again. Go out there and just fly for the joy of flying again, you dont have to be the best, it doesnt matter and never did. Aim to have the best fun! Lol.

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Post  rsv1cox Sun Jul 18, 2021 5:00 pm

Your Sterling P-40 Jim. RIP.

Loved that plane and your adventures with it.

Good memories of mine also, but mine is still in one piece, mainly because I haven't flown it in 25 years.

Good luck with your present project.
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Post  getback Mon Jul 19, 2021 8:01 am

Thanks for the engine suggestions Ken i have the OS 10 FP what prop would work good to keep the speed up ? I don't know what size or length lines to use at the moment just want to write it on the box ,, Thanks
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Post  944_Jim Mon Jul 19, 2021 10:47 am

Eric,

Just for collecting info, can you weigh your engine? I'd like to compare to my options.

TIA!
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Post  Ken Cook Mon Jul 19, 2021 3:09 pm

The FP .10 weighs 4.20 oz's without muffler and they made two different styles of mufflers for that engines. 1 works so so stock and the other will happily overheat the engine. The Fp .10 is somewhat of a rarity in control line form and the needle valve assembly that came with it is worth a king's ransom as they're unobtainable. A FP .10 will have no problem keeping the speed up it turns up and stays there. A thin bladed Master Airscrew 7x4 is a good choice. This engine is somewhat caught between prop sizes as the next size is too much and the next size down is semi small.
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Post  944_Jim Thu Jul 22, 2021 9:35 pm

Thanks Ken,

Ok guys. I am going oh, too slowly! However, the rib centerlines are marked. They only need to be mounted to my wing jig so I can begin the wing build.

All of my available engines have been weighed. I checked from my Norvel Big Mig .15 down to an Enya CL .09 engine. The Medallion .09 is the lightest. The Norvel .15 is too heavy with the muffler-Period!

I'll swing through the Spectre engine review site for power/rpm numbers for the whole bunch. My first choice WAS the Medallion .15, but the OS .10 is just soooo much lighter by better than a half ounce. Suffice to say the engine choice is still up in the air.

Engine // Open Exhaust // Muffler (OS engines/Magnum would use a tongue muffler)

Magnum XL .15 R/C.   5.4 oz.  5.7 oz
Cox Medallion .15        4.3 oz  4.7 oz
Norvel Big Mig .15        4.5 oz  6.1 oz
OS LA CL .15                  4.3 oz  4.6 oz

Smaller options:
OS Max  .10 CL              3.7 oz  4.0 oz
Cox Medallion .09         2.6 oz   unk
Enya CL .09                    3.6 oz   unk

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Post  batjac Fri Jul 23, 2021 1:35 am

Well, speaking as an unrepentant fanboy, there is only one option.  Go for the Medallion 15.  Besides, that's what I put on my Akromaster.

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Post  Ken Cook Fri Jul 23, 2021 4:11 am

The OS MAX .10 is not a OS FP .10 and it's about as gutless as the Enya .09. I've used both the Enya and the MAX but they work better for twins vs singles. Anemic engines work rather well for twin engine planes. While Scepter is great for looking at reviews, almost all of them are positive. I also find many of them to be inflated. I own the AME .15 and I consider it quite light. I don't own the Big Mig but I don't feel the weight you posted on here out of the question. Don't obsess on the weight, if needed add some tail weight.

My one Akromaster which was given to me by a club member had a Mccoy .19 on it. It actually had a fairly sized chunk of lead on the tail but it flew reasonable. We were flying on a asphalt circle for a how low can you go contest. My son was busy grinding down the rudder inverted. Eventually, it caught hard and tore the tail off. I rebuilt it and another member wanted it badly so I gave it to him. I never saw it again.
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Post  944_Jim Fri Jul 23, 2021 8:54 pm

@batjac wrote:Well, speaking as an unrepentant fanboy, there is only one option.  Go for the Medallion 15.  Besides, that's what I put on my Akromaster.

The Loyal Mark


Sold...between Mark and Ken, I'll go with my lightest full-size option...un-muffled, and I'll add the muffler if I need more nose weight. As Mark so eloquently put it...it is the obvious/natural choice given where the build log is! Smile

Thanks both for your input. Now to start the wing...
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