Flew the A-6 today. This plane came out nose heavy as put together as per the plans. If I build another one I will put the elevator sevos in the tail. Here are pre flight pix. Skip

Would it be possible to make a hatch on the bottom rear tailcone and install the servos there? I would rather that they not be visible in such a classic design.

Pardon the dumb question Skip--but how does she fly??

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Being very nose heavy, I'll bet it flies like a John Deere garden tractor.

We can see that you used a four-stroke engine, but which one? My memory is toasted, so if you mentioned it before, I apologize.

You did a nice job assembling the ARF, by the way.

One thing that springs to mind is that in "the olden days", we had to have AMA and our number on the wings of at least 1" minimum vertical height in order to fly in an AMA sanctioned contest. Realize that I am pulling up memories from the Seventies and Eighties.


Ed Cregger

Oh no! No after flight pictures is not good.

Skip

I suspect the cg is for the plane as originally designed calling for a 61 2c. Randy has flown his with the cg right on the mains and said he may move it back a little more. He like the cg well back. Much as it may offend you, you'll need to start sticking lead on the tail till it's right, they bury it inside. It'll serve you well in Sportsman. Randy as a couple of little issues yet with the Expert pattern, but will work them out.

I would be putting one or maybe two servos in the tail for the elevator depending on how nose heavy the Intruder is. Like Skip, I hate lead in the tail!

Jon

[:@] To all you guys that are wondering where the after flight photos are!! Let me say that I suffered a loss of the crystal in my JR receiver after a few loops rolls etc. The result wasn't pretty. I really was not that wild about the plane so it's no great loss. Besides they are still available. I have always preferred to build my own planes and fly tail draggers ( except during the old days when I used tri-gear retracts). If I did buy another one I would make the following changes: I would locate the elevator servos in the rear. I would make it a taildragger, I would strip the covering off the bottom wing and make it really visible to tell top from bottom. There isn't a hell of a lot of room to do a proper installation in the servo bay area. There are pre-glued servo bays which I found to be more of a hindrence than help. But for a few hundred bucks it ain't bad. I'm sure the right pilot can win with it. These are just my opinions and you may not necessarily agree with me. That's OK.

Hey Skip,
One of the interesting design changes for that airplane was the diamond shape horizontal stab. Did this airplane have that? Judging from the pictures it looks like it is a standard symetrical stab.

Thanks

Greg Grigsby

Do you think the crystal was damaged from the 4S vibration and limited space for foam around the receiver? I had a sinking feeling when you posted pre-flight and no in flight or after flight pictures. But like you said it was only an ARF and apparently one that you will not miss. Your experience reinforces my thoughts that the Carolina Custom Aircraft A-6 kit would be a better buy.

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I'm sorry to learn of Skip's loss.

In my mind, the WM A6 and the Carolina Custom Aircraft A-6 are not in competition with each other at all. No doubt that the CCA A-6 is an infinitely more competitive model that is intended for serious SPA competitors. While the WM A-6 is meant for folks that want an ARF model that requires little additional work to provide something to practice with and with which to show up at a meet in order to participate without going through months of building, etc. I, for one, would not expect an ARF to be comparable with a custom model such as CCA's A-6, yet it has its place.

A Moto-Tool with a ball mill and a means of lowering the speed is ideal for removing someone elses idea of how the radio package should be installed. I seldom agree with the manufacturer regarding pre-installed servo trays. Moving the R/C system battery behind the trailing edge of the wing, inside of the fuselage, would have to help remedy the CG situation. I wouldn't go with rear mounted servos in such a model. Too much work for little gain. It is an ARF, after all. Let's see it for what it is instead of trying to make a silk purse from a sow's ear.


Ed Cregger

Your point is a valid one. I don't mind adding my own ideas to an ARF if I think it's worth it. I have had the Carolina Models A-6 and it was small but a nicely made kit. The new A-6 ARF is an OK plane but I would love to have a fiberglass fuse and foam cores and make my own SPA plane. I get really frustrated with the lack of SPA planes available. If you like Daddy Rabitts you'll be fine but the ARC is pricey but well made by Dennis Hunt. I am from the old school and prefer to build kits. I hate scratch building. I will now tape on my JR crystals in the future. You're never too old to learn!! Skip

Ok guys, I feel like I need to share my observations about the WM A-6 Intruder, I hate to see this plane get a bad rep right out of the chute. I have flown about 1 gallon through mine and this is what I have found. The CG will definitely have to be moved back regardless of how you choose to do it. We modified the old WM Intruder about 3-4 yrs ago with the symetrical stab from the Zen 120 and enlarged the rudder. The designers at WM worked closely with SPA members in the redesign and re-introduction of this plane, to make it more competitive right out of the box. They added the airfoil stab, enlarged the rudder, stretched the fuse a couple of inches and built it lighter along with other minor changes. This plane flies very similar to my old one, but with the lighter weight it excels in vertical maneuvers. I find it very capable of serious pattern competition. Whether you choose it as a pattern plane or a sport flier, this really is a good flying plane-This ARF is definitely more than just a practice plane, I like my sow's ear pretty well...

PS Skip, sorry to hear about your plane. I just wish you had got to fly it more.[]

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I'm not the greatest builder in the world, so a sow's ear ARF is likely to be better than anything that I can whip up. My point was that each type of model can serve a useful function. I did not intend to berate the WM ARF version of the A-6. I'm glad it is available. Yes, I have one.

I hope they did not copy the diamond airfoil shape of the original Kirkland A-6's horizontal stabilizer. The purpose of the diamond airfoil shape was to produce the same effect of today's exponential function - to desensitize an elevator that had enough control throw to force the model into a spin or snaproll upon demand. Remember, radios did not have expo or dual rates when Jim designed this model. I know you old timers already know this, but we may have some younger SPA enthusiasts on board and reading our banter.


Ed Cregger

I just might put together another A-6 in the future. I will make some major changes to this ARF and I think it will make it a better plane. I still wish I could get my hands on an old SPA legal kit with a fiberglass fuse. They are almost impossible to find these days. I prefer foam wings and stab too. They seem to take more abuse and are vitually the same weight as a buit up wing if done correctly.

Skip

Deadstick still has the molds and is kitting the A-6 that Kirkland designed.

Jon

I'll second what Randy said regarding the Intruder's flight characteristics. It's certainly much more then a good practice airplane. It's all in getting the airplane (any airplane) properly setup, which should and will take more than a couple visits to the field. This is certainly an area where it pays to "split hairs" to get it done right. It could mean the difference between an OK airplane and a great airplane that you really would miss if something should happen to it.

I was the modeler approached by W-M regarding the modifications SPA flyers were making to the airplane. I was merely a mouthpiece for all the guys, such as Randy, Sid and all that were flying the plane before me, to relate the majority of things they were doing to improve an already darn good airplane. When we first got into SPA (fall of 05) Randy and some of the others related to us what needed to be done to make the plane better, and we listened. One thing that was universal across the board though, was everybody adding tail weight to get the plane in trim. It was my brother John's idea to stretch the tail some to alleviate that problem, so he did on his plane, 7/8". And it worked well. I was second to get mine going after considerable trouble sourcing stabs, and after spending some time on the sticks of John's I settled on stretching mine 2-1/2", and I went to work to lighten the front of the airplane. Mine has no tailweight and flew right in trim with respect to CG right off. I showed WM exactly what I did and from what I can tell from talking with modelers who have the new bird, it appears they stretched it 2" and went about the lightening in a different (read safer for the knock-around flyer) way.....although mine took a good "thump" without breaking when a tree in Cullman jumped right in my way last season.

Point is whether the plane is scratch, kit or ARF built, don't give up on it until it's trimmed, otherwise you're cheating yourself and you'll never know how good the plane can be. One thing you must realize is if WM or any manufacturer for that matter states a CG that is "right on", and you miss rearward by a half inch, and your plane snaps in, you won't be the only one and then they have an epidemic and everybody says the plane is flawed, and nobody buys one. If they state it conservatively and you miss the mark by a 1/2" rearward, your plane flies great and you recommend it to others and buy another yourself. WM isn't concerned how many Intruders win contests, they just want flyers to enjoy them enough to buy another one.....and they'll leave the "hair splitting" to us.

Interesting about the diamond shaped stab. I'm not an expert in airfoil design so I was wondering what is the down side to having a diamond shaped stab now?

Thanks
Greg Grigsby

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The only real downside is if you are like me and do not like the exponential function.

At the time that Jim employed the diamond shaped stab airfoil, contemporary servos were not that great at recentering. Fuzzy trimming around neutral on the elevator was acceptable, maybe even desired by some pilots, hence the diamond airfoiled horizontal stabs popularity for a while.

Today, our servos (and control linkage set ups) are much more precise. I would rather be able to choose the amount of "fuzziness" myself via the electronic adjustment capability of my transmitter, or even that available with some digital servos than to be saddled by the arbitrary amount that was imposed by the mechanical system of the airfoil shape.


Ed Cregger

Thanks Ed for the reply. Unfortunately, my brother and myself were with my dad at Jim's house when he had to be taken to the hospital and passed away. Very sad.

Greg Grigsby

I'm not so sure about the attributes of the so called `Diamond' stabiliser. I fly an Astro Hog, Orion, Taurus, Concord and Superstar, all with what you would call a `diamond' tail section and I have yet to detect any `soft neutral' effect. This in comparison with Nimbus, Perigee, Atlas, Super Kaos and Curare with the `standard' symmetric section. Perhaps you are confusing this with the `negative expo' effect of rotary servo outputs...
Evan.

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No, I'm not confusing it at all. I'm merely passing on the theory that was published in the model mags at that time. I have never flown a diamond airfoil shaped stabilizer equipped model myself. But even if I had and still felt the same way - you would be entitled to your opinion, even if opposite of mine.

You may be correct in its true effectiveness/lack of effectiveness. I have no first hand, empirical knowledge. But the mags were full of talk about this feature in the late Sixties thru Seventy.

Gregg: You are lucky to have met Jim Kirkland. I never had the opportunity. Even though I was about 22 years old at the time and a little old for having modeling heroes, Jim Kirkland was as close as anyone could come to be one - til Joe Bridi came on the scene. I rank them equally. <G>


Ed Cregger

I think that one reason Jim designed the diamond stab was for the ease of construction. He could build the stab flat on the bench. Jim used saddle jigs for his wings and stabs. I just got through designing and building a symetrical stab for my Bobcat. I used a saddle jig to build it. While not to difficult to make a saddle jig, it does take time and building a stab flat on the bench is easier.
Jim test flew my first R/C airplane, a Guillows Vanguard. It crashed! Not Jim's fault, though. I was a 13 year old kid and I used a hand drill to wind the rubber on my Babcock escapement. No, not a electrical hand drill but the old wind by hand type. However, I didn't know that they were geared 5/1. The instruction said to put 100 turns on the rubber. Well, being geared 5/1, I put 500 turns in and the escapement locked hard over as soon as the airplane left the person's hand who was hand launching it. My beautiful(to me) Vanguard was in a bunch of pieces on the asphalt. Learned a lesson, though!
Frank