bp,
Your post was a graphic illustration of how turbulent rotor can be. Scarier events than I have ever experienced. Also, very interesting observations about "conical" mountains.
My experience with rotor has been exclusively at or below the mountain tops. All my wave flying above the tops (up to FL240), has been in completely smooth conditions. I asked a glider pilot friend of mine who is also a commercial pilot, about his experiences and how the autopilot manages in wave conditions. He sent me an extensive, very interesting reply, which I am quoting, with his permission:
Wave effects are quite noticeable. One of the big surprises of jet flying was how often we do see wave, and how widespread it is. Wave caused by strong wind over T-storm lines can be run into every month of spring, summer, and fall. None of the pilots I fly with, recognize the name Cowley [ed. known to glider pilots as "Canada's Diamond Mine"], but everybody knows where I am referring to, if I mention the speed bump on the way from Vancouver to Winnipeg. We often see wave around Thunder Bay, also. Sugarbush is a good place to see wave. I have seen lenticulars over every province, and territory, except maybe PEI.
The effect of wave is two fold - wave and turbulence. We don't see much turbulence due to wave - besides climbing/descending in and out of Calgary. Most turbulence is wind shear generated by the jet stream, although we can get some interesting interaction when a jet stream over-runs wave activity.
The autopilots maintain an altitude hold and the auto throttles maintain a Mach or IAS hold. The autopilots are very assertive about altitude, but the auto throttles are very damped. If I'm too busy to look at the airspeed in some situations, I will just start to push or pull the throttles in the opposite direction to the one they are trying to drive to.
A consideration for most jets is that we run very close to Mmo/Vmo. The other night we were showing an airspeed of 253 kts at 37,000', Vmo was 266 kts, and the stall buffet warning (the speed at which a "g" loading of 1.3 would stall the aircraft) was 231 kts. So, 35 knots between stall and over-speed warnings. At the first feel of the aircraft rising, pilots will put hands on power levers and at 5 knots or so will start adjusting the power, depending upon the rate of acceleration. Excursions of 7 knots or greater will usually see us reset the target speed to the middle of the band. The autopilot will usually hold within 100 feet. If the airspeed excursions start getting greater, we advise ATC and start flying attitude accepting the deviations to moderate the airspeed excursions. Maybe once every year or two, the excursions can be +/- 600' with speed changes of +/- 10-15 kts. The most extreme event I am aware of, was when a friend of mine ran into wave at Cowley and ended up 1600' above initial cruise of FL410 while “sharply" reducing power, and still getting the occasional over-speed alarm.
In a follow-up, I asked him about what altitudes he has experienced rotor turbulence, relative to the mountain tops:
Rotor turbulence will be significantly below the tops of the lenticulars of course. As a rough rule of thumb - coming into Calgary I figure when wave is possible - if it is smooth above 14,000' it will likely be rough below, if it is rough above 14,000', often it is smooth below. And it is a rapid transition from smooth to rough - rarely over 500' vertically. So that is 4-5,000' above the ridgeline tops. Driving further east past the foothills at 16,000' before letting down over the flat land (10 nm) will almost always avoid the majority of the rotor, unless the tertiary lennies are in serried ranks east of Calgary.
There are very interesting theories about the behaviour of single mountains vs ranges in wave conditions - with vortices/and all sort of singularities being identified - but the common thread is a narrow lift band and greatly disturbed flow up to near the heights found along ranges.
Finally, with reference to the Mt. Fuji accident, he made this observation about the relative strength of jets, compared to the towplanes we both fly:
The vertical "g' limits for certification in the transport category are (to a little airplane guy) frighteningly small, being just +2.5 to -1.0, compared to the +3.8 to -1.52 Normal category, and +4.4 to -1.76 Utility category. Both the 182 and Scout are certified Utility category at reduced weight. (Flaps down is +2/-0, but that's the same for pretty well all aeroplanes).