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Old 21st December 2008 | 18:38
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safetypee
 
Joined: Dec 2002
Posts: 2,776
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From: UK
… prefer to be a little fast in turbulence …
… any structural risks when not slowing?


There’s turbulence and turbulence. Being a bit fast in cobblestones might be more comfortable, but a critical point might be if the turbulence is an indicator of a more severe condition.

A personal, pre-planned encounter with a Cb in a fully instrumented civil aircraft flying at turbulence speed resulted in reaching both limiting positive and negative ‘g’ values within a 10 sec period. The vertical air currents were estimated between 3-6000 ft/min which also caused large roll angles, one of which ‘spat’ the aircraft out of the side of the cloud at stick shake alpha – total duration 30 sec. This test condition was not repeated!

A more realistic operational (unplanned) encounter involved a very smooth clear night climbing out of Greenland ~FL200, when a severe up-gust above a lenticular cloud produced a harsh pitch up of about 1.5g briefly. Full forward stick was required to maintain some control of the decreasing speed whilst balancing the duration of flight at less than 1g.

Speed limits are published for good reason.
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