Brett Buck's Starter Package?

The Aeromaniacs web has a trainer "package" described by Brett Buck for learning PA. In the pictures it shows the engine, an OS 20 or 25FP with muffler, mounted as far forward on the fuselage as possible. Is this necessary for proper CG? Or for some other reason?

Like everything else in the world, modelling and learning to fly don't have totally strict rules to follow. There are lots of gray areas. I have not (yet) seen the article at Heman's site that you referred to, but if you were dealing with a sizeable model, with which you wanted to use the smallest and lightest engine that would work with it, you surely might want to mount the engine far forward.

It's a far better solution to the CG problem than mounting lead weights on the nose. I just checked, and found a discussion of the stunt model trainer based on a SIG Skyray 35 that has converted Dan (young curmudgeon aspiring to be as grouchy as his elders) R. into a BB-fan. If it works, there's a picture here now.

That isn't "just" a trainer at all. For BASIC training the Aeromaniacs web site espouses the 049 engine size. Heman is located on the west coast, where the ground will shake some, but the leaves in the trees barely wiggle, the breezes are so mild most of the time. Here where I have done the majority of my own flying, there are just too few days with perfect weather, so we fly on moderately windy days, and leave the 049's at home.

A Brodak kit of a Streak Trainer is what we suggest around here for that BASIC level, with an engine in the 15 to 19 range. And we will mount lighter weight 15's way out front that same way. After getting past the "overcontrolled" porpoising flight that characterizes beginners, if stunts are next to learn, Skyrays work quite well.

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Kiwi

The prescribed trainer package is a SIG Skyray 35 with the OS 20/25 fp. La would probably work in there too. Standard muffler and mounted as far forward as possible. Little nose heavy on this airplane wouldn't hurt.

Thats a pretty easy to build airplane capable of flying really nice and gentle with plenty of power from those engines. I used to fly mine with a fp40, man did that have nose weight. Went where you pointed it, that's for sure.

>The Aeromaniacs web has a trainer "package" described by
>Brett Buck for learning PA. In the pictures it shows the
>engine, an OS 20 or 25FP with muffler, mounted as far
>forward on the fuselage as possible. Is this necessary for
>proper CG? Or for some other reason?

It's that far forward because there were too many other engine mount holes, and I wanted to miss them. It went from 40FP, to Fox 35, to OS20FP, to McCoy 19rr, to 15FP, and then back to 20FP. But the holes were so messed up that I moved it forward to get some fresh wood. Note also the "bare wood" (actually covered with clear, of course) where there was a spacer so that the McCoy and 15FP could be mounted. Subsequently, I faced off the engine mount area and rebuilt it, and now the engine is a little further back.

BTW - it balances pretty much right where it needs to (15% chord) as shown. This was the post-wing-rebuild, so it only weighs about 29-30 oz. (as opposed to 36 from the kit).