flying through cb(s)
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Confident young SAAF fighter jock in a Mirage tried to fly over one at night over the African highveld (elevation 5000 feet) Got to about fl 430 in full afterburner and lost it - recovered at about 7500 feet. His report made for sobering reading!
SN3 - He talks the truth!
SN3 - He talks the truth!
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I had a difficult one to judge day before yesterday:
I was flying into Naples LIRN, coming from the NE, scanning with the Radar. From ontop there were no huge CBs, as far as I could see, just what I assume to be the mountains depicted on the radar. getting in coser (the ILS starts at 7000', A/D elev ca 300') I reduced my range, and got a huge red one right on the ILS. Somehow I didn't believe it, there was nothing indicating big TS before. I have seen Radars overdraw at close range, so I told the FO to keep on flying. He was twitching a bit in his seat, but I asked him again and again if he was still ok with the situation, or if he wanted to goaround (wich would have taken us the same way, and it would not have been smart to take a turn off the ILS, because of the high MSAs around us.
The radar indication was a clear "do not go there", but the assesment of the situation before the approach said "it's ok".
I really wasn't sure what to do - high terrain, red blob on the radar ahead, in clouds! As we didn't get hit any harder than heavy rain, I decided to continue, and so did the FO...
There was no severe Turbulence, no hail, just a lot of rain, and an uneventful landing.
Either we just got lucky, or the assesment from high altitude proved to be right (I lean towards that one) - but on an approach to another airport with easier terrain, I would have broken off, to reevaluate...
Nic
I was flying into Naples LIRN, coming from the NE, scanning with the Radar. From ontop there were no huge CBs, as far as I could see, just what I assume to be the mountains depicted on the radar. getting in coser (the ILS starts at 7000', A/D elev ca 300') I reduced my range, and got a huge red one right on the ILS. Somehow I didn't believe it, there was nothing indicating big TS before. I have seen Radars overdraw at close range, so I told the FO to keep on flying. He was twitching a bit in his seat, but I asked him again and again if he was still ok with the situation, or if he wanted to goaround (wich would have taken us the same way, and it would not have been smart to take a turn off the ILS, because of the high MSAs around us.
The radar indication was a clear "do not go there", but the assesment of the situation before the approach said "it's ok".
I really wasn't sure what to do - high terrain, red blob on the radar ahead, in clouds! As we didn't get hit any harder than heavy rain, I decided to continue, and so did the FO...
There was no severe Turbulence, no hail, just a lot of rain, and an uneventful landing.
Either we just got lucky, or the assesment from high altitude proved to be right (I lean towards that one) - but on an approach to another airport with easier terrain, I would have broken off, to reevaluate...
Nic
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It is not just the CBs I have a strange event that come to mind.
I was flying a Seneca five to Malaga single pilot five years ago with its owner. I was flying at FL120 across the Madrid area. Ground temp at Madrid was 44 deg C
There were two large CBs left and right of my track so a picked a clear way between the two with blue sky above.
The aircraft was on autopilot.
All of a sudden I could not believe my eyes as the airspeed needle zoomed down from 155 KTS ias to 70 KTS ias in seconds.
I knocked the autopilot off puched the nose over and added power. The aircraft felt as if it had flown into a vacuum with no control response and no increase in IAS. The aircraft vertically dropped 2000 feet like an esculator. It all felt tame and surprisingly unscary. Then the feeling was like hitting air again and everything came alive. I have experienced wind shear before but nothing quite like that! anyone any ideas? As this felt more like flying into a Vacuum.
Pace
I was flying a Seneca five to Malaga single pilot five years ago with its owner. I was flying at FL120 across the Madrid area. Ground temp at Madrid was 44 deg C
There were two large CBs left and right of my track so a picked a clear way between the two with blue sky above.
The aircraft was on autopilot.
All of a sudden I could not believe my eyes as the airspeed needle zoomed down from 155 KTS ias to 70 KTS ias in seconds.
I knocked the autopilot off puched the nose over and added power. The aircraft felt as if it had flown into a vacuum with no control response and no increase in IAS. The aircraft vertically dropped 2000 feet like an esculator. It all felt tame and surprisingly unscary. Then the feeling was like hitting air again and everything came alive. I have experienced wind shear before but nothing quite like that! anyone any ideas? As this felt more like flying into a Vacuum.
Pace
Lack of clouds or precip doesn't mean no outflow and flight into areas that show lack of precip on wxr may only mean you flying into the the heart of a developing demon straight from the pit of the darkest region of Hell.!!!..icing I'm ok [in GA ops] I've been there.... I get out---CBs
---I've never relinquished the respect or terror
PA
---I've never relinquished the respect or terrorPA
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Radar doesn't differentiate between a cumulonimbus and simply a heavy downpour of rain. Certain discriminating modes such as windshear prediction do look at the movement of the moisture that's reflecting the radar energy and make certain elementary calculations, as does the turbulence mode to a certain degree. However, when all is said and done, what you're seeing is a return on moisture. In general, the larger the moisture droplets, the greater the return. However, the greater the water density or saturation, and the higher the moisture content in the cloud, also the greater the return.
When approaching a return, scanning up and down to examine the return is important, as well as necessary to help discriminate between cloud and ground, or even cloud and abberations caused by an imperfect radome or dish problems. The latter two can cause different features such as lobe projections (streaks going away from the aircraft-center of the return) or simply cause attentuation, reflection, refraction, or dark spots that don't show what's reallyout there. These returns and the character they impose on what you see on the radar changes with temperature and moisture; if you have a poorly sealed radome, for example, and you're flying in moisture, you're going to be accumulating moisture in the radome and the character of what you'll see will change. Especially with changes in the range.
When you do shift from long range to shorter ranges, then you're going to see the instensity and of course size of the return change, as depicted on your screen.
Beyond about 80 miles, you're not seeing much of value anyway; if you've been watching at longer ranges and then come in, suddenly you're going to see appear what may not have appeared before as you look at a narrower band with a greater concentration of energy, and closer reflective ranges. You can work with the intensity squelch feature of your set to change what you're interpreting at longer distances. Suffice it to say that if you're not frequently tilting up and down as well as ranging in and out, you can easily miss important information on radar. Radar is every bit as much about what you're not seeing, as what you are seeing.
So far as rapidly building cells or the turbulence that grows between them...your parents may have told you not to walk between parked cars in a parking lot, but rather to walk around them. That was good advice which also applies to flying between cells in a line of thunderstorms. Very strong shears can exist between them, not simply vertical shears inside the storms. Vertical shears can be far in excess of 12,000 fpm; vertical shears can be created as the pressure changes in the airmass draw air from higher pressure to low.
Last year while flying a thunderstorm penetration in a Lear 35A, I was working at night, adjacent to a very strong return with a very steep gradient. This was indicated by a thin line of green a thin line of yellow, then all red. I was on the upshear, or upwind side of the cell. It was very sizeable. My purpose in being there was to take samples of the atmosphere around the storm, and start working into some of the developing cells on the upshear side. A thundercell isn't simply a system of vertical currents; it's constantly forming on the upshear side, constantly dying and falling apart on the downshear side, even though it doesn't look that way. A steady wind blows through the storm, from upwind to downwind, as the storm is constantly being created and dying. My mission was to find an area of maximum icing in the cells that were being created, and begin firing flares and pyrotechnics into the building cells from the minus ten degree level so they could be tracked and recorded with some specially enhanced ground based radar. Aircraft were flying beneath the storm base taking readings, as well.
I made several passes, getting a little closer each time, through the narrow green edgeof the cell. We were in and out of cloud a lot in the dark, with both radar and visual cues by lightening to guide us. I passed the cell and started a left turn around one side of the cell, with nothing but black on the radar scope. At that point we entered a building cell on the upshear side, apparently. We immediately got the shaker and then the pusher. We fell sharply and the aircraft rolled right past 90 degrees. Everything that wasn't tied down went up. One of the systems operators in back broke his headset (my headset that he was wearing). My laptop computer, in a paded case in the baggage section) was pulled apart, with the internals actually pulled out of the computer case), and it hurt. We had flown through a minor shear.
It became very quiet. I applied maximum thrust, pushing the thrust levers to the stops and then retarding them an inch, applied forward stick pressure, and recovered to wings level as we flew out of a stalled, unusual attitude condition; unusual because we were nose down steeply, rolled past 90 degrees, stalled, without much aerodynamic response to control input. Due to the violence of the encounter, I elected to recover at a nearby field and re-evaluate, before going back out.
Don't underestimate a cell. With up and down shears that can damage an aircraft all by themselves, the sum of their velocities are compounded; a 6,000 fpm downshear against the same value going up (entirely possible) is a 12,000 fpm shear. It can break your airplane and do things to you that you probably can't imagine. The upset we experienced was fairly minor. We were in a small, robust airplane. We were also in somewhat of a remote area, in the dark. It can, and will rattle you. It can, and will disorient you. It can cost you control of the aircraft rapidly and make recovery difficult. It can rapidly place you in an unusual attitude, cause engine stalls or flameouts, tumble instruments. Negative loadings can damage wings and control surfaces, cause oil or fuel starvation, do engine damage, and of course, hurt people inside the airplane.
I always like to compare the thunderstorm to the finger of God. We're the mosquito, and there you have an apt comparison to where you stand in your aircraft (be it a single engine Cessna, four engine B747, or built-like-a-tank F-16) in the face of a real cell. Nothing to fool with, everything to respect, always something to avoid if you can at all do so.
When approaching a return, scanning up and down to examine the return is important, as well as necessary to help discriminate between cloud and ground, or even cloud and abberations caused by an imperfect radome or dish problems. The latter two can cause different features such as lobe projections (streaks going away from the aircraft-center of the return) or simply cause attentuation, reflection, refraction, or dark spots that don't show what's reallyout there. These returns and the character they impose on what you see on the radar changes with temperature and moisture; if you have a poorly sealed radome, for example, and you're flying in moisture, you're going to be accumulating moisture in the radome and the character of what you'll see will change. Especially with changes in the range.
When you do shift from long range to shorter ranges, then you're going to see the instensity and of course size of the return change, as depicted on your screen.
Beyond about 80 miles, you're not seeing much of value anyway; if you've been watching at longer ranges and then come in, suddenly you're going to see appear what may not have appeared before as you look at a narrower band with a greater concentration of energy, and closer reflective ranges. You can work with the intensity squelch feature of your set to change what you're interpreting at longer distances. Suffice it to say that if you're not frequently tilting up and down as well as ranging in and out, you can easily miss important information on radar. Radar is every bit as much about what you're not seeing, as what you are seeing.
So far as rapidly building cells or the turbulence that grows between them...your parents may have told you not to walk between parked cars in a parking lot, but rather to walk around them. That was good advice which also applies to flying between cells in a line of thunderstorms. Very strong shears can exist between them, not simply vertical shears inside the storms. Vertical shears can be far in excess of 12,000 fpm; vertical shears can be created as the pressure changes in the airmass draw air from higher pressure to low.
Last year while flying a thunderstorm penetration in a Lear 35A, I was working at night, adjacent to a very strong return with a very steep gradient. This was indicated by a thin line of green a thin line of yellow, then all red. I was on the upshear, or upwind side of the cell. It was very sizeable. My purpose in being there was to take samples of the atmosphere around the storm, and start working into some of the developing cells on the upshear side. A thundercell isn't simply a system of vertical currents; it's constantly forming on the upshear side, constantly dying and falling apart on the downshear side, even though it doesn't look that way. A steady wind blows through the storm, from upwind to downwind, as the storm is constantly being created and dying. My mission was to find an area of maximum icing in the cells that were being created, and begin firing flares and pyrotechnics into the building cells from the minus ten degree level so they could be tracked and recorded with some specially enhanced ground based radar. Aircraft were flying beneath the storm base taking readings, as well.
I made several passes, getting a little closer each time, through the narrow green edgeof the cell. We were in and out of cloud a lot in the dark, with both radar and visual cues by lightening to guide us. I passed the cell and started a left turn around one side of the cell, with nothing but black on the radar scope. At that point we entered a building cell on the upshear side, apparently. We immediately got the shaker and then the pusher. We fell sharply and the aircraft rolled right past 90 degrees. Everything that wasn't tied down went up. One of the systems operators in back broke his headset (my headset that he was wearing). My laptop computer, in a paded case in the baggage section) was pulled apart, with the internals actually pulled out of the computer case), and it hurt. We had flown through a minor shear.
It became very quiet. I applied maximum thrust, pushing the thrust levers to the stops and then retarding them an inch, applied forward stick pressure, and recovered to wings level as we flew out of a stalled, unusual attitude condition; unusual because we were nose down steeply, rolled past 90 degrees, stalled, without much aerodynamic response to control input. Due to the violence of the encounter, I elected to recover at a nearby field and re-evaluate, before going back out.
Don't underestimate a cell. With up and down shears that can damage an aircraft all by themselves, the sum of their velocities are compounded; a 6,000 fpm downshear against the same value going up (entirely possible) is a 12,000 fpm shear. It can break your airplane and do things to you that you probably can't imagine. The upset we experienced was fairly minor. We were in a small, robust airplane. We were also in somewhat of a remote area, in the dark. It can, and will rattle you. It can, and will disorient you. It can cost you control of the aircraft rapidly and make recovery difficult. It can rapidly place you in an unusual attitude, cause engine stalls or flameouts, tumble instruments. Negative loadings can damage wings and control surfaces, cause oil or fuel starvation, do engine damage, and of course, hurt people inside the airplane.
I always like to compare the thunderstorm to the finger of God. We're the mosquito, and there you have an apt comparison to where you stand in your aircraft (be it a single engine Cessna, four engine B747, or built-like-a-tank F-16) in the face of a real cell. Nothing to fool with, everything to respect, always something to avoid if you can at all do so.
Guppy, that's extremely interesting and scary reading---I can't believe you went back up
Does your Lear have special any modifications for such rough stuff?
I'd always wondered about the ships they use for wx research---although Con-Pilot also elucidated some facts---still I only fly in CB's from a nice air conditioned class room
PA
Does your Lear have special any modifications for such rough stuff?
I'd always wondered about the ships they use for wx research---although Con-Pilot also elucidated some facts---still I only fly in CB's from a nice air conditioned class room
PA
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The aircraft was used for a lot of purposes. It had underwing hardpoints with pylons, flare racks underneath, cameras, onboard computers and monitors, all kinds of gear. Nothing in terms of significant structural modifications, however. Generally penetrations were flown at 180 to 200 knots, due to equipment limitations of sensors on the wings.
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I think he meant sheer(windsheer) vs a Microburts..
You can have windsheer and not have thunderstorms overhead...
Posit that anyone in here stating they are flying into thunderstorms as part of research in a small general aviation aircraft are typing these posts from the underworld.
You don't fly through CBs, everyone knows this. Hurricane chasers can in large C130s and such, specialy built to handle the turbulance, and they pick thier way through it as best they can, with more then typical radar setups.
You can have windsheer and not have thunderstorms overhead...
Posit that anyone in here stating they are flying into thunderstorms as part of research in a small general aviation aircraft are typing these posts from the underworld.
You don't fly through CBs, everyone knows this. Hurricane chasers can in large C130s and such, specialy built to handle the turbulance, and they pick thier way through it as best they can, with more then typical radar setups.
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Sheer?
W/O looking at a dictionary, I'm going to guess that Sheer means semi-transparent. Shear, on the other hand means Cut, or Sever. As in scissors being "shears". There's spelling, and there's ignorance. Mis-spelling "Windshear" is a suggestion to consider the qualifications of the person posting. Then there is a "MICROBURT". Is that a small friend of Ernie?
This is beyond a Pedantic; minimums apply to writing as well as Flying, IMHO.("Turbulance"- a Piper in Moderate? "Thier"? no idea) Specialy?
Airfoil
This is beyond a Pedantic; minimums apply to writing as well as Flying, IMHO.("Turbulance"- a Piper in Moderate? "Thier"? no idea) Specialy?
Airfoil
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A guy that has such an appalling knowledge of basic English certainly has no place in a cockpit. The terms are germane to the profession and don't need a bloody spell checker.
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If turbulence and icing are not enough to put you off, also consider performance.
Cb's can have huge sudden temperature changes, if the temp goes up and you're up high, you can easily lose performance and the only way is down.
Cb's can have huge sudden temperature changes, if the temp goes up and you're up high, you can easily lose performance and the only way is down.