WingedFrog
Well Known Member
Coming from Mike Busch, a guru on GA engines, this is big!
https://www.youtube.com/watch?v=jOsCBrQMzWY
https://www.youtube.com/watch?v=jOsCBrQMzWY
I think if "FAA Inspector" is that concerned, he should probably not buy a Rotax 912 series engine.
The 912 series have been around long enough, and there are enough in production (and flying) that I think if the so-called "downsides" were real issues, we'd be hearing a lot about them. I think there are some real misconceptions "Inspector's" epistle, like his understanding of the alternator and regulator and whether you can design an engine to run reliably at higher RPM than a desk fan. But, as he says, it's all his opinion and everyone is welcome to theirs.
Yes, they are different than Lycomings and Continentals. The overhaul and repair procedures are different. The design philosophy is certainly different. That doesn't mean they are something to regard with fear and trepidation, but if you do, well, by all means go buy an O-200D. For the rest of us, despite their obvious differences from more traditional GA piston engines, it's hard to argue with the demonstrated success over the past few decades.
Kinda sorta but not really. The general layout may show its heritage, but at least Harley has advanced their technology. Even my 14 year old H-D has electronic fuel injection, and a few years later they started using water cooling in the hot parts of the heads. It's driven by emission requirements. They have to burn leaner and leaner to meet emission regs, and that makes it run hotter and hotter (here we go with that again, right?) and requires better control of mixture and timing. I haven't kept up enough to know if they now run closed loop; mine is open loop.After all their design is about the same vintage.
I enjoyed the presentation, thanks for posting. I found it a helpful instructional as to what the Rotax, maintenence, and it's install is about.
But which does create the most drag with a damaged engine? (No power)
A freewheeling prop...or one that's stuck in one position?
Regards,
My understanding has been that, although perhaps counterintuitive, the best strategy is to try to get the prop stopped (stalled) if you have a dead engine. Reason is that it takes energy to keep it turning (think of the effort needed to start by hand propping). That energy is coming from the air against the prop (drag) and is stealing your airspeed and altitude at the worst possible time while you're trying to get max glide. Seems like I recall at least one POH that said if no luck restarting, then pull up to slow down in an attempt to let the prop stop. Kind of a twofer, you (might) gain some altitude (don't stall!) and get a better glide after it stops.
We did the math in University to figure this out, and then I tried it in flight after I got my license and verified it... On a Cessna 150 with a metal prop, and a homebuilt with a wooden prop.But which does create the most drag with a damaged engine? (No power)
A freewheeling prop...or one that's stuck in one position?