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New member, first post,...... but by no means am I a noob. Tom, I can sympathize with your plight and your troubles. I am intimately familar with the simulation of the Garrett TPE331 engine, and I had data from Honeywell to help me along the way, and even then it wasn't an easy task. Your task is monumental. I too look forward to an update, but it looks like it is not to be anytime in the future, so I will be content with the existing model. Thought I could shed a little light on a question asked by Emalice back in #478 : "what you call the props lock, is it that feature where the props will feather on improper shutdown procedure and you then have to press the unfeather button at startup ?" No, the prop locks are a way to lock the pitch of the propeller at a flat setting, so that the starter can rotate the engine and propeller more easily the next time that the engine is started. The MU-2 engine is a single-spool engine, meaning that everything in the engine rotates together, not like a two-spool engine where the propeller is driven by air pressure coming out of the engine. Think of a car with a manual transmission going down a hill. Take your foot off the gas, and the transmission starts driving the the engine. Same thing happens in the MU-2 engine, only in a much more complicated way. There is a system in the MU-2 engine called the Negative Torque Sensing (or NTS) system that will drive the propellers towards feathered (but not completely feathered) if an engine is lost in flight. In simulating the drag caused by a dead engine, I couldn't find any data from anyone, so I used an equation from Roskam's red book, which described the drag coefficient of a propeller as 0.1 + cos(beta)^2, where beta is the propeller pitch angle, and the drag coefficient is based on propeller area. (Sorry for making some of you do math). If the engine fails with the propeller at it's normal working angle, let's say somewhere around 10-15 degrees, the drag of this failed engine can be as high as 600 lbs at slow airspeed. The NTS system drives the propeller towards feathered (maybe to 40-50 deg), which reduces the drag to something around a third of that 600 lbs. The pilot is to manually feather the propeller of the dead engine, thereby reducing the drag of the dead engine further. The NTS system is tested upon startup to ensure proper operation because this system is so critical. I've heard from experts that at 120 knots, an engine failure with a failed NTS system is basically unrecoverable. Good luck Tom. Maybe you can adopt one of my catch phrases, "You can have it right, or you can have it now. You just can't have it right now". Someone pointed out to me recently that the bitter taste of deivering something late (or over budget) is soon forgotten, but the bad taste of a poor product lives a much longer life. Bill

Because the Beaver is THE ultimate bush plane and my absolute favorite when it comes to this type of flying. I love it, and this is what drives me during development. I couldn't just do an aircraft I can't releate to. There are only very few aircraft I would like to develop for X-Plane and all of them are a little older and have some history.