Well, Chuck, I went to my files to read that article, even though the topic was B-36s, and it's not where it's supposed to be. Some times you lend stuff out and it doesn't come back. Old Stu may have had free wheeling props on the model for the article, but I'll bet he didn't actually fly it much with them. The Ford Tri-Motor has an incredible amount of drag as it is , without adding to it with two big discs doing no work on on the wings. In the case that was being discussed, the B-36, you might as well have four parachutes hanging off the trailing edges of the wings, and that model would have to fly much faster that the Tri-Motor, and the increased speed also increases drag. You know what a feathered prop is for , correct? Ever hear of a runaway prop on a full scale airplane? This is the kind of stuff I'm talking about. I just consulted with a friend of mine on a B-17 he built, that uses two engines, and for static display, he installs two more props on the outboard nacelles. They are removed for flying because of the drag, and there can even be a heck of a harmonic vibration from the spinning props that can cause problems. This is typically what is done with multi engine planes to simplify the construction and operation of the model when you can't for some reason use a full compliment of engines. One purpose of picking a multi-engine model for a subject to model is the extra points awarded in scoring, but I do believe you have to demonstrate that all engines can and are running for flight points, and in the case of the B-36, and not knowing the exact rules, what bonus points would be awarded for only having two of the six engine operable. That is what I mean by saying "that actually works." And airplane, to me , is the sum of all of it's parts, and anything that goes into the air should be fulfilling a purpose and doing some work. Sure, you could do it, but there are far more reasons not to do do it than there are pluses for it. Every once in a while, you have to land a model dead stick, and those spinning props where ever they are certainly do no help in a situation where you are running out of airspeed, altitude and ideas all at the same time. You have to notice, if you read the available model publications that are currently available, and the older magazines, or go the the Nationals and other scale contests, that this is NOT a common practice, and probably for a lot more reasons than what I have included here. You mangaged to dig up one example, but I'll bet you will have a hard time finding another.
GOD BLESS JIMMY STEWART!!!
Dan McEntee
fYI,, I judge scale,, so I know a little, not an expert but a little,,
in order to obtain any points on the flying score, all engines must remain flying for the flight, any engine not running does not obtain bonus points...
as to frewheeling props,, one of the first observations flying electric stunt with ONE electric motor,, when the motor quit, and the prop freewheeled, the airplane came DOWN to the ground,, NOW,, later experiments showed that using the braking action of the speed control to stop the prop allowed the airplane to glide normally to a landing..
to operate a B-36 with two motors, and the other props spinning would require a substantial increas in the size and power of the two motors providing power to overcome the drag,, and in addition, any variation in friction on the freewheeling props would cause potential serious yaw issues,,
Topic: B-36 (Read 2884 times)
