Turbulence - What happened?

Been flying 16-20 (mostly 4+ hours) flights a month for 10 years now.
I have certainly encountered turbulence and bumpy flights before, as
well as the hard landings that any frequent flier has. Ive been in a
few scary landings in Northern Canada in blizzards in small planes as
well. Ive even done some basic acrobatics training in a T-6 with a
full complement of maneuvers.

Ive been on a few flights where one or two people were making noise
and puking, but on a recent trip from Thessaloniki to Frankfurt though
I encountered my first flight where most of the plane was screaming
and in fact praying. Myself, I wasnt quite sure whether it was
something to worry about or not. The plane was a 737 IIRC, and a newer
model. Anyways, it wasnt a tiny plane, but not a wide body.

Somewhere over the mountains the plane started into some quite heavy
winds. A few bumps, but then it proceeded to feel light the pilots
were really having to work the plane. The whole incident lasted 20-30
minutes as the pilots tried to get free from it. There were more than
a dozen times where the plane descended quickly enough that if not for
the seatbelt I would have floated up (not flown out, but it was like
an extreme drop on a roller coaster and there is no doubt that without
a seat belt Id have been holding on or out of my seat). Mostly the
plane kept going down in extremes, although the pilots of course many
times brought it back up. When the descents occurred, a loud buzzing
could be heard over the wings. It sounded like the spoilers had been
fully lifted, but Im guessing this is not something that would be done
in flight anyways, and looking at the wing it certainly was not the
case.

The plane didnt pitch noticably, but it did roll a bit, and yawed a
lot.

Sorry for any technical misuse - but how usual is this? Was it
anything to be worried about.

On Sun, 17 Jun 2007 07:27:36 -0000 'Wanderer'
posted this onto rec.travel.air:

Been flying 16-20 (mostly 4+ hours) flights a month for 10 years now.
I have certainly encountered turbulence and bumpy flights before, as
well as the hard landings that any frequent flier has. Ive been in a
few scary landings in Northern Canada in blizzards in small planes as
well. Ive even done some basic acrobatics training in a T-6 with a
full complement of maneuvers.

Ive been on a few flights where one or two people were making noise
and puking, but on a recent trip from Thessaloniki to Frankfurt though
I encountered my first flight where most of the plane was screaming
and in fact praying. Myself, I wasnt quite sure whether it was
something to worry about or not. The plane was a 737 IIRC, and a newer
model. Anyways, it wasnt a tiny plane, but not a wide body.

Somewhere over the mountains the plane started into some quite heavy
winds. A few bumps, but then it proceeded to feel light the pilots
were really having to work the plane. The whole incident lasted 20-30
minutes as the pilots tried to get free from it. There were more than
a dozen times where the plane descended quickly enough that if not for
the seatbelt I would have floated up (not flown out, but it was like
an extreme drop on a roller coaster and there is no doubt that without
a seat belt Id have been holding on or out of my seat). Mostly the
plane kept going down in extremes, although the pilots of course many
times brought it back up. When the descents occurred, a loud buzzing
could be heard over the wings. It sounded like the spoilers had been
fully lifted, but Im guessing this is not something that would be done
in flight anyways, and looking at the wing it certainly was not the
case.

The plane didnt pitch noticably, but it did roll a bit, and yawed a
lot.

Sorry for any technical misuse - but how usual is this? Was it
anything to be worried about.

The northern hemisphere jetstream heads down over the Balkans and
Greece and this is most likely what you encountered.

Probably the most recent bout of severe turbulence I encountered was
heading west over India towards Dubai from Bangkok 18 months ago in
an Emirates B767. It maybe lasted 25mins and happened just after a
meal had been served up, so that exacerbated the problem.

I also encounter strong jetstream currents flying from Europe to
South America when crossing the equator.

The upside is that when you're going the other way it can knock
a lot of time off the journey without much turbulence.

The reasons are clear: very strong and fast jetstreams.

Wanderer writes:

Somewhere over the mountains the plane started into some quite heavy
winds. A few bumps, but then it proceeded to feel light the pilots
were really having to work the plane. The whole incident lasted 20-30
minutes as the pilots tried to get free from it. There were more than
a dozen times where the plane descended quickly enough that if not for
the seatbelt I would have floated up (not flown out, but it was like
an extreme drop on a roller coaster and there is no doubt that without
a seat belt Id have been holding on or out of my seat). Mostly the
plane kept going down in extremes, although the pilots of course many
times brought it back up. When the descents occurred, a loud buzzing
could be heard over the wings. It sounded like the spoilers had been
fully lifted, but Im guessing this is not something that would be done
in flight anyways, and looking at the wing it certainly was not the
case.

The plane didnt pitch noticably, but it did roll a bit, and yawed a
lot.

Sorry for any technical misuse - but how usual is this? Was it
anything to be worried about.

Sounds like heavy turbulence, but nothing dangerous. If nobody came back with
broken arms or legs, you weren't even close to the tolerances of the airframe,
so there's nothing to worry about. Even when unfastened people in the
aircraft _are_ injured, it's generally still too gentle to pose any threat to
the airframe.

Unfortunately, where there are mountains, there tends to be turbulence, even
in clear air and sometimes even well above the mountaintops. Sometimes
there's no easy detour (and it may not even be possible to figure out where
the turbulence starts and stops), so you have to just fly through it.

On 17 Jun, 08:27, Wanderer wrote:
Been flying 16-20 (mostly 4+ hours) flights a month for 10 years now.
I have certainly encountered turbulence and bumpy flights before, as
well as the hard landings that any frequent flier has. Ive been in a
few scary landings in Northern Canada in blizzards in small planes as
well. Ive even done some basic acrobatics training in a T-6 with a
full complement of maneuvers.

Ive been on a few flights where one or two people were making noise
and puking, but on a recent trip from Thessaloniki to Frankfurt though
I encountered my first flight where most of the plane was screaming
and in fact praying. Myself, I wasnt quite sure whether it was
something to worry about or not. The plane was a 737 IIRC, and a newer
model. Anyways, it wasnt a tiny plane, but not a wide body.

Somewhere over the mountains the plane started into some quite heavy
winds. A few bumps, but then it proceeded to feel light the pilots
were really having to work the plane. The whole incident lasted 20-30
minutes as the pilots tried to get free from it. There were more than
a dozen times where the plane descended quickly enough that if not for
the seatbelt I would have floated up (not flown out, but it was like
an extreme drop on a roller coaster and there is no doubt that without
a seat belt Id have been holding on or out of my seat). Mostly the
plane kept going down in extremes, although the pilots of course many
times brought it back up. When the descents occurred, a loud buzzing
could be heard over the wings. It sounded like the spoilers had been
fully lifted, but Im guessing this is not something that would be done
in flight anyways, and looking at the wing it certainly was not the
case.

The plane didnt pitch noticably, but it did roll a bit, and yawed a
lot.

Sorry for any technical misuse - but how usual is this? Was it
anything to be worried about.


Many kids love this sort of thing...Me, not so much...

What I worry about is that drinks trolly flying all over the cabin.
I know they stop serving but you cannot predict turbulence. Actually
sometimes I see passengers complain when they stop serving..!

Craig Welch writes:

You refer to the pilots 'really having to work the plane', 'pilots of
course many times brought it back up'. It was likely on autopilot the
entire time.

Maybe, although they may have shut off altitude hold or other modes in heavy
turbulence, as some autopilots try to correct excessively for small excursions
in altitude. The actual movements of the aircraft are only a few feet, and
sometimes it's easier to turn off some modes of the automation and just let
the aircraft ride through the turbulence, with occasional inputs from the
pilots to keep it from drifting too much (it will tend to fly straight and
level by itself, but turbulence might gradually cause course or altitude to
drift slightly).

To be clear - I wasnt concerned about the airframe. I know they can
take a LOT. But how hard is it to control by the pilots in such a
situation?

And our movements were more than a few feet in this case for sure -
the plane was being pushed down enough to cause me to rise out of my
seat and float for 5+ seconds if I didnt have my seatbelt on. A few
feet wont do that.

Also any idea what the buzzing was? Was it just air moving down over
the wing?