flying through cb(s)
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Bookworm permit me to doubt that you have ever been inside a real CB 
You might have been close to or dodged some, flown in between some others, but I seriously doubt that you will willingly flew into any kind of CB (in which case I sure never want to be in any kind of craft in your company...)
And yes, I think most of us still manage to operate regularly and safely during spring and fall convective weather, "religiously" avoiding CBs by flying between them, no big deal, just daily bread!
You might have been close to or dodged some, flown in between some others, but I seriously doubt that you will willingly flew into any kind of CB (in which case I sure never want to be in any kind of craft in your company...)
And yes, I think most of us still manage to operate regularly and safely during spring and fall convective weather, "religiously" avoiding CBs by flying between them, no big deal, just daily bread!
Bookworm permit me to doubt that you have ever been inside a real CB
I have certainly flown clouds of type 3, and I would be amazed if you hadn't, because if they're embedded then you won't tell them apart from the rest of the cloud you're flying through. The radar just shows you precipitation, not CBs as such, and the precip may be very light, none in parts. While (despite the nimbus) cumulonimbus is not strictly necessary for convective precipitation, most convective precipitation comes from CBs. Can you really tell me that you've not flown through cloud producing convective precipitation?
I've flown through some CBs that I'd rather not have, and I've avoided lots that I was not going to go within many miles of -- what you would rightly call "real CBs". But that avoidance was not on the basis of whether or not they were CBs, but the precipitation, vertical extent etc.
The point I'm making is slightly deeper than scoring a cheap point on a meterological definition. There is a continuous progression from innocent little cumulus to mean SOB thunderstorm. At no point does the cloud put a sign up on its edge saying "Don't fly through me I'm too nasty now".
Instead we all have to build an understanding of the danger signs and the criteria we will use for avoidance need to me more subtle than "is it a CB?".
Please would you confirm what level of pilot's license you hold.
So what sort of cbs are we talking about? European cbs, Equatorial cbs, central USA cbs?
To paraphrase George Orwell "all cbs are equal, but some cbs are more equal than others!"
To paraphrase George Orwell "all cbs are equal, but some cbs are more equal than others!"
bookworm: beat me to it. like your response!
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Somewhere in my house I have a United States Army Air Force manual titled "Weather Flying" that belonged to my father that he kept from when he was in basic flight training dated 1941.
Although I must paraphrase here I clearly remember some of the statements in this manual convening Thunderstorm penetration. It went something like this;
1. When approaching a line of heavy thunderstorms fly toward the area of heaviest rain.
2. Avoid areas with frequent and heavy lighting.
3. Fly aircraft at reduced airspeed.
4. Lower seat to lowest position possible.
5. Turn all cockpit lights to full bright.
6. Secure all lose items in cockpit and cabin.
8. If possible restrict aircraft altitude to below the freezing temperate level.
9. Enter thunderstorm at lowest altitude while still keeping a safe level above terrain.
Then the manual went on to make statements such as, safe flight in thunderstorm can be completed, try to avoid green clouds as that is an indication of hail, expect heavy water leakage into cockpit, etc
Well I can certainly attest to the water leaking into the cockpit from my old DC-3 days, and not even close to any thunderstorm, just good rain.
When I first started my aviation career as a pilot I flew with a lot of World War II era pilots. As 411A said, until the jet-upset accidents started happening most of those guys considered thunderstorms just another cloud.
I also flew thunderstorm research many, many years ago in a (believe it or not) Twin Comanche. However, I never actually penetrated any cells, not on purpose anyway, I flew around the bases recording data and firing off flares. It was a study conducted by the US Air Force, NOAA and the University of Oklahoma. The aircraft used were, Twin Comanche (me), Cessna 401, T-28, F4 and a modified B-57 Canberra. There was a F-100 used as well, however, it flew through a heavy area of hail at very high speed and although the pilot was able to land the aircraft it was written off.
Trust me, we have thunderstorm super-cells in Oklahoma that top FL60.0 +. One does not mess with them. Matter of fact one should not mess with any thunderstorm.
Although I must paraphrase here I clearly remember some of the statements in this manual convening Thunderstorm penetration. It went something like this;
1. When approaching a line of heavy thunderstorms fly toward the area of heaviest rain.
2. Avoid areas with frequent and heavy lighting.
3. Fly aircraft at reduced airspeed.
4. Lower seat to lowest position possible.
5. Turn all cockpit lights to full bright.
6. Secure all lose items in cockpit and cabin.
8. If possible restrict aircraft altitude to below the freezing temperate level.
9. Enter thunderstorm at lowest altitude while still keeping a safe level above terrain.
Then the manual went on to make statements such as, safe flight in thunderstorm can be completed, try to avoid green clouds as that is an indication of hail, expect heavy water leakage into cockpit, etc
Well I can certainly attest to the water leaking into the cockpit from my old DC-3 days, and not even close to any thunderstorm, just good rain.
When I first started my aviation career as a pilot I flew with a lot of World War II era pilots. As 411A said, until the jet-upset accidents started happening most of those guys considered thunderstorms just another cloud.
I also flew thunderstorm research many, many years ago in a (believe it or not) Twin Comanche. However, I never actually penetrated any cells, not on purpose anyway, I flew around the bases recording data and firing off flares. It was a study conducted by the US Air Force, NOAA and the University of Oklahoma. The aircraft used were, Twin Comanche (me), Cessna 401, T-28, F4 and a modified B-57 Canberra. There was a F-100 used as well, however, it flew through a heavy area of hail at very high speed and although the pilot was able to land the aircraft it was written off.
Trust me, we have thunderstorm super-cells in Oklahoma that top FL60.0 +. One does not mess with them. Matter of fact one should not mess with any thunderstorm.
Psychophysiological entity
Take this exact view but from the deck outside. 1,250' amsl.
Now imagine a dark night with a clear view of the stars. In the distance we watched the most fantastic display of vast and very tall Chinese lanterns flashing away over most of the horizon you can see in the pic. It was stunning and very beautiful...but something was wrong: there was not the slightest sound.
I was really puzzled and looked at the radar channel on T/V which was live. They were 300 miles away well north or Dallas!
Now imagine a dark night with a clear view of the stars. In the distance we watched the most fantastic display of vast and very tall Chinese lanterns flashing away over most of the horizon you can see in the pic. It was stunning and very beautiful...but something was wrong: there was not the slightest sound.
I was really puzzled and looked at the radar channel on T/V which was live. They were 300 miles away well north or Dallas!
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World's Largest distributor of used aircraft parts - Thunderstorms.
None of you mentioned the turbulence detection feature of the modern Wx radars. It won't detect turb where there's no moisture, but will do a fine job of highlighting areas of moderate and greater turb in the presense of precip, out to 50-60 miles.
How many of you line pilots are satisfied with the ground school you have received on CBs and Wx radar? Most training I have seen is pathetic. Airlines seem to assume their pilots have received the training by the time they are Air Transport Pilot rated.
GB
None of you mentioned the turbulence detection feature of the modern Wx radars. It won't detect turb where there's no moisture, but will do a fine job of highlighting areas of moderate and greater turb in the presense of precip, out to 50-60 miles.
How many of you line pilots are satisfied with the ground school you have received on CBs and Wx radar? Most training I have seen is pathetic. Airlines seem to assume their pilots have received the training by the time they are Air Transport Pilot rated.
GB
SEA Cb
Just back from a tour of Oz and SEA--a question on this topic
South of, and inbound to, KL in front of us was a large pile of thoroughly bad looking storms. At FL 470, HUD says we will not top them, radar tilted down 2-3 degrees confirms LOTS of rain, captain says the radar at zero tilt doesn't paint anything, so we clear I ask to deviate right and its granted, but just in the nick of time. Some clouds are still growing and we cleared on building Cu by a little.
Any advice of dealing with weather in that area? Different than my experience in the Midwest and Southeast US, I would guess.
GF
South of, and inbound to, KL in front of us was a large pile of thoroughly bad looking storms. At FL 470, HUD says we will not top them, radar tilted down 2-3 degrees confirms LOTS of rain, captain says the radar at zero tilt doesn't paint anything, so we clear
I ask to deviate right and its granted, but just in the nick of time. Some clouds are still growing and we cleared on building Cu by a little. Any advice of dealing with weather in that area? Different than my experience in the Midwest and Southeast US, I would guess.
GF
Tabs please !
The updraughts in a Cb can lift lumps of ice the size of your fist high into the stratosphere so go figure.
Never ever intentionally fly into one. Remember that embedded Cbs can be embedded in cloud........or embedded in darkness. A friend of mine took a short cut in a 777 based on what the wx radar said and even with the throttles at idle and the spoilers fully deployed, he was climbing
Never ever intentionally fly into one. Remember that embedded Cbs can be embedded in cloud........or embedded in darkness. A friend of mine took a short cut in a 777 based on what the wx radar said and even with the throttles at idle and the spoilers fully deployed, he was climbing
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GF,
Remember that your radar can't paint the tops of the clouds; when you look to see what's there, you're not seeing what's there.
Someone I know destroyed both engines on a weather research airplane just a few years ago He caught the tip of something around 35,000 or so, in the dark. He was painting down and contrasting it against the terrain. A zero tilt check showed nothing ahead. he intended to overfly the cell for some tops measurements with the onboard sensors and probes, then drop down and start working around some of the upcoming towers feeding into it.
His last words, reported to me, were "let's see what this one's got." He wasn't killed, though his employer certainly thought about it. What was in there was very large hail, and it hammered the airplane severely...breaking fan blades, crushing spinners, crushing nacelle leading edges and wing leading edges, shattering the radome, etc. Overflying the cell can be a risky thing to do, especially one that tall. What's visible in the cell is only part of the picture.
A very general rule of overflight is that you should stay at least 1,000 above the cell tops for every ten knots of wind at your altitude. If you have 70 knots of wind, you need an additional 7,000 above that cell. Any cell above 30-35,000' should be considered severe, regardless of the location, and treated accordingly. Don't think simply because it's found in the ITCZ or a subtropical location, that it lacks energy; that could be a fatal mistake.
I've been monitoring weather closely in the middle east, just lately, and not long ago saw some severe weather putting out 1" hail (in, of all locations, a place called "hail."). You might be surprised what pops up when you least expect it.
Remember that your radar can't paint the tops of the clouds; when you look to see what's there, you're not seeing what's there.
Someone I know destroyed both engines on a weather research airplane just a few years ago He caught the tip of something around 35,000 or so, in the dark. He was painting down and contrasting it against the terrain. A zero tilt check showed nothing ahead. he intended to overfly the cell for some tops measurements with the onboard sensors and probes, then drop down and start working around some of the upcoming towers feeding into it.
His last words, reported to me, were "let's see what this one's got." He wasn't killed, though his employer certainly thought about it. What was in there was very large hail, and it hammered the airplane severely...breaking fan blades, crushing spinners, crushing nacelle leading edges and wing leading edges, shattering the radome, etc. Overflying the cell can be a risky thing to do, especially one that tall. What's visible in the cell is only part of the picture.
A very general rule of overflight is that you should stay at least 1,000 above the cell tops for every ten knots of wind at your altitude. If you have 70 knots of wind, you need an additional 7,000 above that cell. Any cell above 30-35,000' should be considered severe, regardless of the location, and treated accordingly. Don't think simply because it's found in the ITCZ or a subtropical location, that it lacks energy; that could be a fatal mistake.
I've been monitoring weather closely in the middle east, just lately, and not long ago saw some severe weather putting out 1" hail (in, of all locations, a place called "hail."). You might be surprised what pops up when you least expect it.
SNS3:
Thanks a lot. I am new at the "high altitude" flight (above 410), all my previous experience in the Thirties (C-5, sometimes low 30s) and 450 and above seems to be a "silver bullet" to some. "We'll top it, no worries", but I agree that if you are not topping by a lot, DON'T and a whole bunch might not work. Glad to hear the 1,000 ft/10 knots of wind verified, I have heard that before.
Your experience does NOT, I take it, relieve ITCZ and tropical storms from being a concern, then?
GF
Thanks for your great stuff, BTW
Thanks a lot. I am new at the "high altitude" flight (above 410), all my previous experience in the Thirties (C-5, sometimes low 30s) and 450 and above seems to be a "silver bullet" to some. "We'll top it, no worries", but I agree that if you are not topping by a lot, DON'T and a whole bunch might not work. Glad to hear the 1,000 ft/10 knots of wind verified, I have heard that before.
Your experience does NOT, I take it, relieve ITCZ and tropical storms from being a concern, then?
GF
Thanks for your great stuff, BTW
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Basic radar usage videos are a great help on learning to avoid severe weather. Learning how to see the big picture, long range radar, and as you get closer use the shorter range to avoid the close stuff, using the tilt properly and gain control out of the auto mode should keep you safe. I have managed to get through a lot of really bad weather without any problems with what those videos teach. After 23,000 hours with no incidents flying the US and especially MIA and down south in the summer time feel common sense and radar knowledge should keep you safe. One time leaving Managua, Nicaragua I lost all radar when it started smoking in the cockpit. Turned it off but knew coming in there were thunderstorms on my route. I deviated off course as I did landing 2 hrs before but was in the clouds so did not know how things had changed and of course ATC had no radar. Another one of our AC was coming north from Costa Rica so I asked him to scan my airway and see if the deviation was adequate. He confirmed it was with his AC radar and all was well until Grand Cayman where the wall of cells extended all the way to mexico from cental Cuba. I rerouted over the eastern part of Cuba and was able to land at MIA visually avoiding cells. Guess that was my most marginal radar encounter. If used properly airborne radar should make it a safe flight.
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Remember that your radar can't paint the tops of the clouds; when you look to see what's there, you're not seeing what's there.
First you must find the radar top. Start by scanning the parallel beam position. Once you get a good echo, continue to increase the tilt until the echo disappears. Note the tilt. Now we can find the actual radar top. The formula is simple and is as follows:
distance to echo x 100 x degrees of tilt change from parallel beam = radar top
So for example we have an echo 40 miles out. We increase the tilt until the echo falls off the screen and we needed 4 degrees of tilt to do so.
40 x 100 x 4 = 16,000. Therefore the radar top is 16,000 feet above the current flight level. To find an approximate actual top we multiply the 16,000 in this example by 120% and the actual top comes out to 19,200 ft above the current flight level.
Remember the actual top is always 120% of the radar top that we found using the said formula.
Hope someone else found this little tid bit as interesting as I did. It's good to know!
this thread is ultra enlightening---I'm not as brave as Guppy though--I'll go way around or land--though I'm glad some brave souls do the research tho----
PA
PA
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distance to echo x 100 x degrees of tilt change from parallel beam = radar top
Even at that, where the return runs out isn't necessarily the top of the cloud or the storm. Where the cloud ends may be much higher, as may turbulence. The returns will change as the cloud glaciates (turns to ice) and starts to decay.
A good rule of thumb, rather than attempting to climb over, is just to go around. When trying to plan a path across a cell by figuring the tops, you may be surprised if the cell continues to climb. It can continue to build, or additional cells build much faster than you can climb...and it may well be attenuating things building behind it. Best to go around.
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I did not say where the tilt runs out is the top of the storm, hence the formula to find the radar top and then the approximate actual top. This is from our company (legacy US carrier... you guess which) 757/767 flight manual. I don't think it's lying to me.
Kind regards.
Kind regards.
