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Old 8th May 2012, 23:05
  #563 (permalink)  
DozyWannabe
 
Join Date: Jul 2002
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Lyman,

This is the definition of "Moderate" turbulence, but the bolding is mine:

Turbulence that is similar to Light Turbulence but of greater intensity. Changes in altitude and/or attitude occur but the aircraft remains in positive control at all times. It usually causes variations in indicated airspeed.
or
Turbulence that is similar to Light Chop but of greater intensity. It causes rapid bumps or jolts without appreciable changes in aircraft altitude or attitude.
From : Tutorial: wind shear and turbulence

The meteorological categories for wind gusts in general (as measured with an anemometer) are:
Category 1: weak — ≥ 5 m/s to <10 m/s
Category 2: moderate — ≥ 10 m/s to <15 m/s
Category 3: strong — ≥ 15 m/s to <25 m/s
Category 4: severe — ≥ 25 m/s
The meteorological categorisation restated for vertical gust measurement might be:
Weak — ≥ 16 fps to <25 fps
Moderate to strong — ≥ 25 fps to <50 fps
Strong to severe — ≥ 50 fps to <80 fps
Extreme — ≥ 80 fps (or 66 fps [20 m/s] might be used)
Note that Moderate doesn't even come close to the equivalent of 100kts (50fps = 29.6kts).

Outside of the numbers, I sat in the sim - I saw it happen and I *heard* it happen. I experienced an infinitesimal fraction of the concern and fear those pilots felt as the aircraft ran away from me. I stand by the assertion that the climb, warning and deviation from assigned altitude were predominantly caused by deliberate action by the PF.

I can't convince you - of this I'm sure. But I've gone to further lengths than I ever have before - assisted by people to whom I am in eternal debt - to prove that I'm not talking out of my ar*e here, and I'm as certain as it's possible to be that the aircraft did nothing to make things harder for them.
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