Clouds

[facthunter]

When I was there an ATPL holder was regarded as an accredited Met. Observer. Just what status that would have in the current system eludes me. Nev

 

 

[Guest Andys@coffs]

When I was there an ATPL holder was regarded as an accredited Met. Observer. Just what status that would have in the current system eludes me. Nev

Indeed the better ones observed from a distance the others from inside looking out....white knuckled!

 

Its an area of knowledge that I know Im deficient in...I know that grey bottomed Cu that are very deep should be avoided if at all possible, and from first hand experience clouds are hard to see out of and are tightly coupled to your pucker valve muscles..... I also know that the flat bottoms are very flat and who from the ground would have thought that?

 

So, if you wanted to find a school room environment where you can be taught and ask questions etc, who is aware of a good instructor in this space?

 

 

[facthunter]

Don't think there will be any. There will still be older book references out there. Meantime watch out for boiling cauliflower clouds with an anvil on the top, as they drop monster hailstones downwind of the overhang. Could even be 20 Kms away and that will ruin your day whatever you are flying. Nev

 

 

[turboplanner]

Indeed the better ones observed from a distance the others from inside looking out....white knuckled!Its an area of knowledge that I know Im deficient in...I know that grey bottomed Cu that are very deep should be avoided if at all possible, and from first hand experience clouds are hard to see out of and are tightly coupled to your pucker valve muscles..... I also know that the flat bottoms are very flat and who from the ground would have thought that?

 

So, if you wanted to find a school room environment where you can be taught and ask questions etc, who is aware of a good instructor in this space?

Who else but your good old instructor before he sends you off on your first NAVEX

 

 

[ayavner]

i am studying this very topic as i prepare to take my PPL(A) and I have to say that while I understand each thing as i read it, as a whole the topic baffles me... I am studying the Bob Tait PPL book and the ATC Meteorology book. I don't seem to be able to put it all together into a cohesive "whole" that i can comprehend, so I am stuck with memorising "facts". Very frustrating.

 

i do understand the operational stuff pretty well however, reports, forecasts, requirements, etc... its just the science behind it all I can't seem to knit together.

 

 

[turboplanner]

Each morning when you get up there will be a different cloud formation, different winds, different atmospheric pressure etc.

 

I found observing that and trying to match that with my notes every morning was helpful, but I'm the first to admit I'm still a long way from where I'd like to be, probably because I didn't keep it up after I passed.

 

I also used to get forecasts for my local area and see if I could predict what was going to unfold on the day - that was very useful in building knowledge.

 

But I've never quite managed to bulletproof myself against ever inadvertently flying into cloud without enough room for a 180, and after opening a thread on the subject, it looks as if no one else has managed to either.

 

 

[Gnarly Gnu]

A serious cloud formation:

 

 

 

[facthunter]

Don't be baffled by the science. I love the subject and it has plenty of aspects that don't require a lot of science to understand, that will be useful. They, BOM, can't tell you when it will FOG, or when it does, when it will lift, with all their modelling. They used to rely on observer based figures , balloons for lapse rates (Lapse rates affect stability and the ease with which Cumulus clouds grow etc, air mass analysis and such. You can read the clouds and Cirrus (Mare's tails) will often indicate the approach of a cold front perhaps a few hundred Kms away and you know where the winds are coming from by the MSL Synoptic chart. HIGH to LOW and at 30 degrees to the isobars. Low pressure has the ait travelling clockwise around it, in the southern Hemisphere.

 

Air from the east nor east in Townsville means a low to the north and the air will be Tropical Maritime. Plenty of cloud and potential for a lot of rain (High water content Just a sample but there's a lot more. Local knowledge is important, also.. You knew all of that didn't you?.(.Just found this post lodged so it is a day late.) Nev

 

 

[eightyknots]

A serious cloud formation:

 

You wouldn't want to be flying too close to that!

 

 

[Old Koreelah]

... I also know that the flat bottoms are very flat and who from the ground would have thought that?...

True to an extent, Andy. Yonks ago I followed a thermal right up to a small cu and ended up so close my fin was inside the cloud, but I was outside. The horizon was obscured by the edges of the cloud pouring down out of the updraught. In effect the cloud bottom was the shape of an upturned saucer.

 

Always a surprise in the sky. While it's often possible to predict the weather by reference to the chart, sometimes I get it totally wrong. The chart only shows what's happening on the surface.

 

 

[David Isaac]

True to an extent, Andy. Yonks ago I followed a thermal right up to a small cu and ended up so close my fin was inside the cloud, but I was outside. The horizon was obscured by the edges of the cloud pouring down out of the updraught. In effect the cloud bottom was the shape of an upturned saucer.Always a surprise in the sky. While it' often possible to predict the weather by reference to the chart, sometimes I get it totally wrong. The chart only shows what's happening on the surface.

You wild old bugga flying that close so your fin was in the hole ... lucky you didn't get sucked right up in that damn thing.

I had a mate in a C206 tell me a story way out west flying between centres when he got caught on the fringe of a large CU. He said he will never forget the experience. He said when he realised he was being caught in the up draft he closed the throttle and pointed the 206 down, he said he was right at VNE, throttle closed and still climbing. He doesn't know to this day how he got out of it but said he was absolutely sh!tting himself.

 

 

[dazza 38]

You wild old bugga flying that close so your fin was in the hole ... lucky you didn't get sucked right up in that damn thing.I had a mate in a C206 tell me a story way out west flying between centres when he got caught on the fringe of a large CU. He said he will never forget the experience. He said when he realised he was being caught in the up draft he closed the throttle and pointed the 206 down, he said he was right at VNE, throttle closed and still climbing. He doesn't know to this day how he got out of it but said he was absolutely sh!tting himself.

That is similar to a story Jim Davis told. In his story a Piper Cherokee 6 was sucked into CB and tossed around like a toy then spat out at 16000 feet. Not a good idea to hang around near CB clouds.

 

 

[facthunter]

The updraughts don't start at the cloud base. That is only where the cloud forms due to condensation (cooling below the dew point ( ie 100% Relative humidity). The latent heat of vaporisation (change of state from vapour to liquid) is what gives the clouds their energy. More moisture content = more energy. That is why the biggest Cb clouds form in the tropics. The Adiabatic lapse rate existing is the other factor(normal reduction of temp with height effect which can vary). The cloud will keep going up as long as there is enough heat to keep it hotter than the surrounding air mass. Nev

 

 

[Old Koreelah]

You wild old bugga flying that close so your fin was in the hole ... lucky you didn't get sucked right up in that damn thing.I had a mate in a C206 tell me a story way out west flying between centres when he got caught on the fringe of a large CU. He said he will never forget the experience. He said when he realised he was being caught in the up draft he closed the throttle and pointed the 206 down, he said he was right at VNE, throttle closed and still climbing. He doesn't know to this day how he got out of it but said he was absolutely sh!tting himself.

I don't know about "wild old bugga" David. More like young and indestructable. It was only a little cloud.

Our sailplane training was well-flavoured with stories about people who stuffed up; including the pilot who bailed out after his sailplane got sucked up into a CB.

 

Bits of aeroplane were seen to fall out of the cloud, then much later the frozen body of the pilot, tangled in parachute cords.

 

 

[David Isaac]

Ouch .....

 

 

[eightyknots]

I had a mate in a C206 tell me a story way out west flying between centres when he got caught on the fringe of a large CU. He said he will never forget the experience. He said when he realised he was being caught in the up draft he closed the throttle and pointed the 206 down, he said he was right at VNE, throttle closed and still climbing. He doesn't know to this day how he got out of it but said he was absolutely sh!tting himself.

:yikes:That is crazy.

 

That is similar to a story Jim Davis told. In his story a Piper Cherokee 6 was sucked into CB and tossed around like a toy then spat out at 16000 feet. Not a good idea to hang around near CB clouds.

:yikes:It looks as if you really need to keep a respectable minimum distance from Cumulus or Cumulonimbus clouds! I wonder what the minimum safe distance is?

 

 

[rgmwa]

i am studying this very topic as i prepare to take my PPL(A) and I have to say that while I understand each thing as i read it, as a whole the topic baffles me... I am studying the Bob Tait PPL book and the ATC Meteorology book. I don't seem to be able to put it all together into a cohesive "whole" that i can comprehend, so I am stuck with memorising "facts". Very frustrating.

You're not alone. I've also been making an effort recently to learn more about meteorology by reading books and looking at weather maps etc, but also find it hard to get to grips with once you get past the basics like `hot air becomes lighter and generally goes up' and `rain is wet and usually comes down'. It's an interesting subject, and I'd like to get a better understanding of it. Particularly forecasting. We are lucky these days to have so much weather information available, but because there are so many large and small scale factors that determine what happens where you are, it's not so easy to make sense of it all. Worth persevering with though, as it's such an important factor in flying (safely).

 

rgmwa

 

 

[facthunter]

The structure of a large Cu or Cb is that large updrafts exist inside it. You can expect more turbulence the more active the Cu is. They are like a cauliflower and they boil and tumble near their tops. You won't observe this at lower altitudes. Vertical development " height of the tops", is another indicator and colour ( darker or an ice green colour). The top often blows downwind forming a "anvil" appearance..You can get heavy large hail out of a Cb and be in the sunshine when it hits you so don't fly downwind much less than 20 kms distance from it. Nev

 

 

[ayavner]

this is all very helpful!

 

 

[Gnarly Gnu]

Beautiful thunderstorm and rainbow combination:

 

 

 

[Jabiru Phil]

I took this photo on a flight to New Zealand a few weeks ago. I thought it gives a nice perspective looking down from the top.[ATTACH=full]28964[/ATTACH]

Stoney

 

I gave you a bum steer re the Dynon 10A being able to be configured to take cht and egt probes.

 

They can only be fitted with the Dynon 180. Refer Dynon site.

 

Sorry about my misinformation

 

Hope your trip was uneventful

 

What is the brand of your cht system?

 

Phil

 

 

[Stoney]

 

StoneyI gave you a bum steer re the Dynon 10A being able to be configured to take cht and egt probes.

They can only be fitted with the Dynon 180. Refer Dynon site.

 

Sorry about my misinformation

 

Hope your trip was uneventful

 

What is the brand of your cht system?

 

Phil

 

No worries Phil, thanks for the updated info.

 

The trip was great, my wife and I thoroughly enjoyed it. It was great to catch up with your great bunch at Loxton, we felt very welcome.

 

My CHT is by Aerospace Logic Inc ASL CHT100

 

Please pass our thanks on to all the rest at YLOX.

 

Gary

 

 

[Yenn]

Eightyknots says "It looks as if you really need to keep a respectable minimum distance from Cumulus or Cumulonimbus clouds! I wonder what the minimum safe distance is?

 

There is a published safe minimum distance to fly from clouds. This is not to keep you safe from the cloud and it's winds, but to keep you safe from the IFR plane that could just pop out of it. Assuming you are a pilot, you should already know the distances.

 

 

[turboplanner]

I'd be taking notice of Facthunters 18 Nm or so to get away from the hail stones, but you ask an interesting question and I've never seen a distance quoted.

 

 

[facthunter]

Yenn, the point of being wary of what may pop out of a cloud is a good one. Some feeder service may do a nonprecision approach requiring manoeuvring after let down or be on final straight away. At lower levels you can be right at the base of cloud as long as you are visual, maintaining contact with the ground or water visually. This doesn't give you much warning unless you know exactly where to look..

 

Regarding steaming along with big boomers around you, your normal rules of VFR would be adequate except where the clouds are very large vertically and active in a convective sense. The risk with these is turbulence,lightning and the hail possibility under the overhang from what is termed "anvil" Tops which occur at very high altitudes FL350 + (up to 50,000 feet or more in the tropics.) Nev