My P-38 for 2015, my "Wicked Woman"

[Mitch]

Thank you for the question/comment.

I thought about it, but did not consider it. This is my first build for a flying twin engine plane. I have seen twins fly in competition. I think I know some of the challenges that need to be overcome. I know I do not know everything.

If the model had excess slight wt to starboard, I would have accepted that. With twin motors rotating props in the same direction this plane will be turning left while under power. I will need to do everything I know, to overcome that. I think for the wt of the model 1 more gram to get her balanced side to side is the best solution.

Although I removed the front of the cowls, I noticed they were definitely pointed to the right. Guillow knows this plane needs right thrust. I want this plane to glide straight. As I add power, I will overcome the tendency to turn left by adding right thrust (not changing the rudders). As I increase power I will increase my right thrust. For me a properly trimmed plane will fly in a nice wide circle to the left, (the more the power, the tighter the circle) then straighten out and fly straight during her glide phase.

Mitch

[Bill Gaylord]

Probably good that you balanced it, especially considering that the right wing panel was the one that required weight. With conventional CCW rotating props, the normal torque tendency already favors left hand banking, so the imbalance would exaggerate the tendency. I don't hear this mentioned much, but it's similar to warps, where a warp creating a hair more washout on the right wing panel can actually stabilize flight. Now take the same incidence mismatch, but have the excess washout on the left wing panel, and the model will have a tendency to spin into a left hand banking turn/dive, when added to the prop torque effect.

Being a free-flighter, Mitch is aware of these things, but for those who aren't, this is the best example I have. My Sterman has a slight mismatch that I knew would favor left hand turns. I could have adjusted the rigging, but it was slight, so I basically said aw heck, I'll trim it out. It only took maybe 2 clicks of aileron trim to trim it out and fly fine, but the initial left hand banking turn after launch shows both the effect of a tiny mismatch favoring left hand turning, as well as how little trim is needed to counteract it. For FF, the settings have to be dead on, since there are no aileron servos with remote control trim ability.
https://www.youtube.com/watch?v=2wwF-hfTbtY

[Mitch]

Thank You Bill.

And, yes I will have 2 props pulling my plane to the left. I will have double the force. Some flyers will carve props to have counter rotating props. I do not carve props... yet. Moreover I want to show what can be accomplished from the parts in the kit. I think that is the theme of the contest. The only changes I made is using a tube for the rear peg. (AND secure it) Believe me, the first time you have a peg slip, you will never use a simple wood dowel again. (It was not pretty).

The second change I made is the adjustable front end (still under construction) ...see my "Focke-Wulf Red 13" build.

Both of these alterations are allowed in the G challenge rules and is about 3 dollars in parts from any LHS. Everything else... whoops... I used different tissue. I think that's allowed also. OKAY... everything else is from the kit. Glue paint and dope not included!

Mitch, Keep Building, Keep Improving, Keep Flying!!!

[Mitch]

Hi All,

I've been working on a few different projects...

as for the P-38 I am preparing the plastic parts:

The large air coolers actually had a lot more plastic on them. It would have been the skin covering the entire fuselage over 2 frames. Guillow recommends only just using the air coolers themselves for a free flight model. I may only use them for display because they are located far aft of the cg and are still quite heavy.

I plan to use the forward wheel well cover as it is low and forward and I think it will serve as a landing impact device for the model.

Mitch

PS: There are a lot more plastic pieces that I will not be using but will keep as I may work them into the model when she is retired from flight duty.