Originally Posted by doobierw
Turbulence is a separate issue. We have a Meteorology Dept. that has some of the best turbulence avoidance technology and procedures that are in place within the industry. Our turbulence accident/injury rate reflects that. We use different codes to describe turbulence. When we are in Code 1 or 2 (none, or light) the seatbelt sign is generally off. We generally keep it on during the climb, and maintain that posture until level at altitude and assured that the ride will be as advertised.
Code 3 (moderate) or higher requires the seat belt sign to be on. When we receive a TP (Turbulence Plot) it provides the altitudes and a geographical area that the turbulence can be expected. A report will often state something like "Expect Code 3, Flight level 320-390, in the area bounded by: ORD-MSP-OMA-STL-ORD for instance. That doesn't mean that you will experience Code 3 in every single square inch of that airspace, but that within that area either: everyone else has been experiencing it within various portions of that area, -or- conditions are forecasted to include those conditions. We'll try and fly at 31,000 feet if it's available, or we have the gas to go lower. You will often be sitting in your seat looking at blue sky, in smooth air wondering why the sign is on. We are looking at a lot of messages and listening to a lot of people whining in our headseats about the horrible thrashing their passengers are experiencing at flight level this or that.
Doobierw, really appreciate the information that you have given us about the mysteries of turbulence and procedure. My question for you is why the cockpit doesn't give us a bit more info when we encounter the bumps? On the majority of flights that I've been on, we'll hit turbulence strong enough to make half the people on the plane go, "Wooooo!" and yet have no one come on the PA to say anything.
I bring this up because on a recent DL flight from South America, we encountered quite a bit of turbulence, but the captain delivered a great performance in reassuring us that everything was okay. Every time the seat belt sign was turned on, he came on and told us what was going on, where the storms were, what previous planes had reported, and assured us there was no danger. I thought this was great because many passengers start thinking, "I'm going to die, I'm going to die..."
Contrast this to when stuff starts flying around and you hear the belated seat belt ding with no added info... I always think, great... thanks for telling me something I didn't already know.