Best practice in turbulence
 

Hi,

Can anybody point me in the direction of documents that discuss how best to respond to heavy en-route turbulence/windshear, particularly how best to use the automatics. I remember reading a couple of papers on the topic but can't for the life of me find them again.

Ta

LowFi

If you are on the Boeing then your Vol1 Supplementary Procedures or FCTM are the places to look. Here is the SP for the 737:

Turbulence
During flight in light to moderate turbulence, the autopilot and/or
autothrottle may remain engaged unless performance is objectionable.
Increased thrust lever activity can be expected when encountering wind,
temperature changes and large pressure changes. Short–time airspeed
excursions of 10 to 15 knots can be expected.
Passenger signs ............................................................ .......................ON
Advise passengers to fasten seat belts prior to entering areas of
reported or anticipated turbulence. Instruct flight attendants to
check that all passengers' seat belts are fastened.

Severe Turbulence
Autothrottle................................................ ........................DISENGAGE
AUTOPILOT ............................................................ .......................CWS
A/P status annunciators display CWS for pitch and roll.
Note: If sustained trimming occurs, disengage the autopilot.
ENGINE START switches ............................................................ ....FLT
Thrust ............................................................ .......................................Set
Set thrust as needed for the phase of flight. Change thrust setting
only if needed to modify an unacceptable speed trend.

Table for best speeds here

Note: If an approach must be made into an area of severe turbulence,
delay flap extension as long as possible. The airplane can
withstand higher gust loads in the clean configuration.

Cheers CaptainSandL,

That’s just the kind of thing I was looking for. Raised an interesting
question with a colleague though. Has the CWS mode been removed
from the more modern Boeing aircraft (757/767 onwards) and if so why?

Low Fi

The only thing I can speak for is the 777, that if you are handling normally the input goes through the Flight Control Computer anyway, so in effect you are in CWS continuously!

See the following:

Flight in Severe Turbulence

Windshear training guide