CB sverity differs for different AC-types ?

[OscarTango]

Today at work, we had some pretty big CB's hovering over the Dutch/German border... funny thing is that an aircraft at FL410 ( northbound, if that matters ) chose to circumnavigate, and two aircraft ( southbound ) at FL360 chose to go right through... I don't get it... How much "turbulence" do you encounter flying through/near a CB ? Is it aircraft type related if the pilot chooses to circumnavigate even 40 degrees off track for about 8 minutes... or is it just the pilots choice to offer the passenger the smoothest ride as possible ?:confused:

[slingsby]

CB avoidance in Euro airspace can not always be acheived due to parallel traffic and other factors. What you may have seen is one aircraft able to route around the build up and the others due to the above being forced to fly though. Generally though if ATC are aware of CB activity in a particular area then they will advise following aircraft, and be prepared for wx avoidance requests. However, if your radar doesn't show precipitation ahead and no previous reports of turbulence then wx avoidance not nessesary. In my experience in the Far East, CB's in europe are annoying and bumpy but aren't the wing rippers we can sometimes get around Malaysia. We can be cruising at FL410 and still have towering CB several thousand feet above us. 100 miles avoidances are not uncommon, as are level changes.

Turbulent air penetration generally means a speed reduction, entering any weather is unpredictable, you may pass through with only a moderate bump or you may find the CSD crawling through the flight deck door covered in messy goo from spilt meals. Best idea is to avoid turbulent air if possible, check the weather and wind charts prior to departure. Talk to your CSD and inform him/her of potential turbulent times and areas. He will then plan for meal/drink service to then. Beleive me theres nothing like flying through moderate turbulence when the CSD is trying to hand you both a coffee... Aircraft safety above all else is the priority, unfortunately we may fly where angels tread but we aren't god and cannot control the weather. Sometimes passenger comfort is a seatbelt sign switch but do as much as possible to keep things smooth. Passengers aren't the only ones who don't like bouncing around, I know I don't.

[OscarTango]

thanks for the reply, Slingsby... this "enlightend" me a bit already. I'm not fully qualified for that long a period, so I miss the experience of talking to pilots/other aviation related people... time will solve that, I guess...
You wouldn't happen to have any pictures of those "big" CB's over Malaysia, do you ?

[slingsby]

I'll try and see if any of our guys have them on 'E' format, then i'll post some on here for frightening viewing.

:)

[411A]

If you think they are large in the SE Asia area, you'all should come and have a look at the mid-western USA.

Never found golfball sized hail in Asia (thankfully). No tornados either, just a small waterspout or two...

[Les Bee'un]

Hell 411A - how did we all know you were going to say that.

When you make your P.A.'s do you address yourself as Captain Custer or President Custer? :D :p :D

['%MAC']

Well, I see 411a has increased his list of admirers. But he does have a point here, the mid-west of the United States brews some incredibly violent cumulonimbus. Unlike the storms in the tropics and sub-tropics, the mid-west storms are steady state and can last upwards of 12 hours. The requirements for a severe-thunderstorm are large dew-points (20*C for starters), cold air aloft, dry air at the mid-level, a statically stable layer at low level to initially cap the storm, and strong winds aloft so the storm does not destroy its fuel supply. These factors are most prevalent in the mid-west. I know very little of African climatology, but would suppose great big storms could develop there as well, same with Australia.

[411A]

Gosh LesBee'un, always have the F/O make the PA announcment, that way when they "thump it on" with the landing, they have to explain as well.;)

[dick badcock]

I was at work on the 19th, flying towards this line of CBs making aline from about Luxembourg up along the German border. We were at FL350, and wanted to climb to FL370 which was turned down due to traffic already at FL370. Someone behind us chose to REALLY reroute and ended up going south of Lux (50 NM off course). We found a small gap in the green radar returns and tried to fly through it. No turbulence at all luckily, except for the occational bump. I was flying with a captain that had a lot of experience in flying in the US, so he'd seen his share of squall lines. I guess it depends on your own comfort level and how you are trained. We were down low and therefore could allow a bit of speed deviation (although we had none) whereas the higher you are the smaller that band gets. Therefore at higher altitudes, if you do not know how much turbulence a CB might give, you are better off deviating rather than taking your chances on a smooth ride.

DB

[OscarTango]

That exactly explains why this guy at FL410 chose to reroute, and the two at FL 360 made the decision to try going through/between/whatever... The flight at FL 410 reported that the top of the CB was at about FL 390-400. Don't know how accurate that would be, but fair enough... thanks for the replies, and Slingsby, I'm getting more curious for those pictures :D

[OscarTango]

SLingsby... did you manage to find some Malaysian CD-pictures yet ?

[slingsby]

I have asked one of my photogenic partners to post a few on here, but he's stuck in Jeddah....!!! I'll remind him when he gets back, he normally has his camera sitting on the glare shield during daylight hours so he may take some quite recent ones.

[OscarTango]

Great...thanks...