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Is Clear Air Turbulence becoming more common?

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Re: Is Clear Air Turbulence becoming more common?

#41

Post by zamadatix »

sandywaffles wrote: post #23

> [Clear Air Turbulence] is particularly common around the tropopause, the boundary layer between the troposphere and the stratosphere, at altitudes between 7,000 and 12,000 meters (23,000 to 39,000 feet) . Oh, excellent the altitudes that 99% of aircraft fly at, unaffecting the ultra rich who fly private jets at 40,000k-50,000k+.

You can fly over the tropopause depending how high it is at the specific location (can be lower or higher than the numbers listed) but, by definition, it'll only be "common" to observe turbulence in the range 99% of planes actually fly. I wouldn't read too much into that. As some others pointed out the height difference probably more due tot he space being faster and unused since commercial flights stay to where is more efficient.

Re: Is Clear Air Turbulence becoming more common?

#42

Post by nickjj »

pc86 wrote: post #27
hiatus wrote: post #24

Earlier quoted context omitted.

> Oh, excellent the altitudes that 99% of aircraft fly at, unaffecting the ultra rich who fly private jets at 40,000k-50,000k+. I didn't realize private jets fly so high. What's the reason for the difference in elevations?

Private jets don't really fly at 50k that often but I'm sure there are some that can. 40-42k is pretty common though. There are a handful of reasons. In no particular order: 1) additional separation between recreational private flights and scheduled commercial flights 2) higher performance in small private jets with typically less than 1k lbs of people and cargo 3) winds are generally faster the higher you go so you'…

> 3) winds are generally faster the higher you go so you'll usually go about at high as you're able, at least in one direction.

I recently flew from NYC to Lisbon, Portugal and it was 6.5 hours there (flying east) and 7.5 hours back (flying west) because you go with and against the jet stream.

I wonder if there's a noticeable difference if you fly at a lower altitude against the wind. It didn't seem like the plane adjusted for that, it cruised at the same altitude both ways from what I remember. Both flights used the same exact plane type (A330neo).

Re: Is Clear Air Turbulence becoming more common?

#44

Post by bparsons »

Octabrain wrote: post #31

I hate flying with passion and get extremely scared when flying through turbulences but, there was a journalist in my country, that also had experience as a pilot and said once on TV that during turbulences, is one of the safest moments in a plane. I don't remember the reasons but is there anybody in here with knowledge in the field that could confirm/deny this?

Commercial airliners are built for extraordinary stress on the airframe. You can get a taste of it here: https://www.youtube.com/watch?v=--LTYRTKV_A

Other people will correct me if I am wrong, but I believe the last time a large commercial airliner was lost to turbulence was 1966. https://en.wikipedia.org/wiki/BOAC_Flight_911

Re: Is Clear Air Turbulence becoming more common?

#46

Post by ImaCake »

w14 wrote: post #29

This does not seem to be borne out by the accident statistics, which apparently show no trend in turbulence related accidents. ( https://www.ntsb.gov/safety/safety-studies/Documents/SS2101.... ) I don't know if there are other factors which might be masking a rise in incidence of CAT from accident stats?

Certainly no detectable trend in that data. But the accident frequency is so low that the random variation dominates and makes it impossible to distinguish any trend.

What is demonstrably increasing is CAT, due to climate change. But considering how infrequent these incidents are we might not see a clear increase for several decades.

Re: Is Clear Air Turbulence becoming more common?

#48

Post by stouset »

eggy wrote: post #36
w14 wrote: post #29

This does not seem to be borne out by the accident statistics, which apparently show no trend in turbulence related accidents. ( https://www.ntsb.gov/safety/safety-studies/Documents/SS2101.... ) I don't know if there are other factors which might be masking a rise in incidence of CAT from accident stats?

Yeah, you should have more concern over human error and Boeing than this. But, boy, the more I have flown and the older I am, the more I get anxious during turbulence when I fly.

When was the last time a commercial airliner crashed due to turbulence?

Re: Is Clear Air Turbulence becoming more common?

#49

Post by ThinkingGuy »

Octabrain wrote: post #31

I hate flying with passion and get extremely scared when flying through turbulences but, there was a journalist in my country, that also had experience as a pilot and said once on TV that during turbulences, is one of the safest moments in a plane. I don't remember the reasons but is there anybody in here with knowledge in the field that could confirm/deny this?

Airline pilot/author Patrick Smith has a pretty informative article about turbulence on his website:

https://askthepilot.com/questionanswers/turbulence/

Re: Is Clear Air Turbulence becoming more common?

#50

Post by dclowd9901 »

cpncrunch wrote: post #33
w14 wrote: post #29

This does not seem to be borne out by the accident statistics, which apparently show no trend in turbulence related accidents. ( https://www.ntsb.gov/safety/safety-studies/Documents/SS2101.... ) I don't know if there are other factors which might be masking a rise in incidence of CAT from accident stats?

Also, they just looked at 2 years, so there could be cherry picking. Jet stream is affected by el nino. 1979 was weak el nino, 2020 was moderate la nina. https://ggweather.com/enso/oni.htm

Right, and those two years are generationally distant. Another question I have is if pilots have a stable mechanism (that is, an unchanged objective sensor or something) that records the CAT or if it’s recorded by pilots, whose sensitivity to CAT might differ over time. Didn’t mention in the article how it’s measured.
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