Southwest B737 Overrun @ Chcago MDW
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Willie, you already blew it with your first response that I pointed out shows you out to be a Walter Mitty. If you are a sim instructor on anything bigger than an IBM laptop then I'll eat my hat.
With statements like that above, you have only confirmed that you have no real idea about what you write except that gained reading the instructions that arrives with your latest copy of MS Flight Sim. Why, oh why, do we have to put up with pretenders on these forums? I don't mind the honest questions from pax such as the ones about trying to get airborne again after landing or retracting gear once on the ground. At least they have the decency to tell us that they are indeed not pilots, certainly not airline pilots, and therefore allow us to explain why some things are or are not done.
There are far too many 'pretenders' on this thread who are trying to come across as experienced with the type of operation as the carrier in this accident and then submitting their views as though they know what they are talking about when in fact all they are doing is p!ssing off those of us who are able to spot their Walter Mitty type ramblings which get in the way of reasoned debate based on experience. By raising the matter about autobrakes, Willie Mitty tries to infer that it is possible that Southwest have a policy of not using autobrakes when in fact anyone in this industry who is a B737 pilot, especially those of us who work for companies registered in the first world, know that it would be impossible to even get an AoC if someone were stupid enough to even think of implementing such a policy.
If Wille Mitty Everlearn is a sim instructor (and we don't mean the Microsoft version) and he comes out with more rubbish such as "... I've been lead to believe that auto braking is more effective and efficient than we humans. Have you heard that as well?" then why does he suppose that I, and no doubt most of my colleagues, who do actually fly and operate these types of aircraft into those types of airports in those kinds of weather conditions, should even try and answer him when anyone who is trained on the B737 will know which autobrake settings are the equivalent to maximum manual braking and which are only a deceleration rate.
It's bad enough that some media types read these forums and are fooled by the likes of these Walter Mitty's and then raise the topic as though it is learned opinion when in fact it is little more than wittering s of someone who knows a little about something and nothing about a lot. This forum should be for educated debate and not for eejits to make stupid assumptions or statements about why they think they know all the answers already and are prepared to be judge, jury and executioner.
Those of us who need to will learn from this accident. All the others will get their titillation and continue to try and bluff their way amongst others who know less.
I'm also confused about the SWA policy on the use of Auto Brake. (I have no idea what it is but some air carriers have a DO NOT USE policy. Are they one of those airlines?)
With auto brake selected for landing, why would the crew assist the auto braking by applying Manual brakes? The auto brakes I'm familiar with disengage when manual brakes are applied. So, I do find the sequence of events rather puzzling, don't you? One more point on auto brake. I've been lead to believe that auto braking is more effective and efficient than we humans. Have you heard that as well?
With auto brake selected for landing, why would the crew assist the auto braking by applying Manual brakes? The auto brakes I'm familiar with disengage when manual brakes are applied. So, I do find the sequence of events rather puzzling, don't you? One more point on auto brake. I've been lead to believe that auto braking is more effective and efficient than we humans. Have you heard that as well?
There are far too many 'pretenders' on this thread who are trying to come across as experienced with the type of operation as the carrier in this accident and then submitting their views as though they know what they are talking about when in fact all they are doing is p!ssing off those of us who are able to spot their Walter Mitty type ramblings which get in the way of reasoned debate based on experience. By raising the matter about autobrakes, Willie Mitty tries to infer that it is possible that Southwest have a policy of not using autobrakes when in fact anyone in this industry who is a B737 pilot, especially those of us who work for companies registered in the first world, know that it would be impossible to even get an AoC if someone were stupid enough to even think of implementing such a policy.
If Wille Mitty Everlearn is a sim instructor (and we don't mean the Microsoft version) and he comes out with more rubbish such as "... I've been lead to believe that auto braking is more effective and efficient than we humans. Have you heard that as well?" then why does he suppose that I, and no doubt most of my colleagues, who do actually fly and operate these types of aircraft into those types of airports in those kinds of weather conditions, should even try and answer him when anyone who is trained on the B737 will know which autobrake settings are the equivalent to maximum manual braking and which are only a deceleration rate.
It's bad enough that some media types read these forums and are fooled by the likes of these Walter Mitty's and then raise the topic as though it is learned opinion when in fact it is little more than wittering s of someone who knows a little about something and nothing about a lot. This forum should be for educated debate and not for eejits to make stupid assumptions or statements about why they think they know all the answers already and are prepared to be judge, jury and executioner.
Those of us who need to will learn from this accident. All the others will get their titillation and continue to try and bluff their way amongst others who know less.
posted 11th December 2005 18:18
--------------------------------------------------------------------------------
"I understand the ABS isn't much help on a dirty runway if you don't plant it on the numbers."
Hmmm, I wonder how the "ABS" (sic) knows if it was "Planted on the numbers" or not.
--------------------------------------------------------------------------------
"I understand the ABS isn't much help on a dirty runway if you don't plant it on the numbers."
Hmmm, I wonder how the "ABS" (sic) knows if it was "Planted on the numbers" or not.
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arewenearlythereyet,
quote......"Willie Mitty tries to infer that it is possible that Southwest have a policy of not using autobrakes when in fact anyone in this industry who is a B737 pilot, especially those of us who work for companies registered in the first world, know that it would be impossible to even get an AoC if someone were stupid enough to even think of implementing such a policy."
FYI..The FAA allows US carriers to set their own policy regarding mandatory use of such.
My carrier has a requirement to use autobrakes (if installed-former TWA MD80's aren't so equipped) if the visibilty is below 4000' or 3/4 mile, if the runway is contaminated and if the runway is shorter than 7000'.
As I understand it, SWA did not have a policy requiring use of autobrakes, at the time of this event.
dd.
quote......"Willie Mitty tries to infer that it is possible that Southwest have a policy of not using autobrakes when in fact anyone in this industry who is a B737 pilot, especially those of us who work for companies registered in the first world, know that it would be impossible to even get an AoC if someone were stupid enough to even think of implementing such a policy."
FYI..The FAA allows US carriers to set their own policy regarding mandatory use of such.
My carrier has a requirement to use autobrakes (if installed-former TWA MD80's aren't so equipped) if the visibilty is below 4000' or 3/4 mile, if the runway is contaminated and if the runway is shorter than 7000'.
As I understand it, SWA did not have a policy requiring use of autobrakes, at the time of this event.
dd.
Per Ardua ad Astraeus
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May or may not be relevant to this accident, but I had a very exciting moment or two in KEF at the roll-out end of R02 last winter, following which it was discovered that the last 1000ft or so was NOT grooved like the rest of the runway and it had a b/a of almost zero in snow. It was just that no-one had reported or notammed it until then................................
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Paper today said the crew had trouble getting the reverse thrust levers to move, they might have been distracted by this and if not using auto brake might have delayed the stopping process?
If the throttles are not fully closed the reverse levers will be hard to move and even jam until the throttles are properly closed. This has happened to me and others several times in the sim, but luckily not in the airplane.
In these circumstances any delay would be a bad thing.
If the throttles are not fully closed the reverse levers will be hard to move and even jam until the throttles are properly closed. This has happened to me and others several times in the sim, but luckily not in the airplane.
In these circumstances any delay would be a bad thing.
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So, latest Update from an Yellow-Press-german Paper (This means: ACCEPT THIS INFORMATION WITH CARE!)
The Capt was a 58-Year Old Veteran being with WN since 1978 having logged almost 19.000 Fhrs in Total
The F/O seems to be a 32-Old Guy having accumulated about 4.700 Fhrs Total and was recently hired after Serving some years with another 737-Operator (I assume he was laid off from either ATA or UAL)
If the CPT is really that old I think this was unfortunalety his last flight.
Investigations normally take months and I assume WN will take him out of Service untill it is proofed that this was in the first line (Or totally) a technical Error if his licence is not frozen yet by Administratives.
This would protect him to be part in another incident that might will happen and WN would be protected against the bad press etc in such a case.
As far as I know, Pilots in the US are not allowed to operate pax-planes after their 60th Birthday (For Cargo I am not sure).
So, if Investigations take more than 6 Months he will most propably not return into the cockpit
The Capt was a 58-Year Old Veteran being with WN since 1978 having logged almost 19.000 Fhrs in Total
The F/O seems to be a 32-Old Guy having accumulated about 4.700 Fhrs Total and was recently hired after Serving some years with another 737-Operator (I assume he was laid off from either ATA or UAL)
If the CPT is really that old I think this was unfortunalety his last flight.
Investigations normally take months and I assume WN will take him out of Service untill it is proofed that this was in the first line (Or totally) a technical Error if his licence is not frozen yet by Administratives.
This would protect him to be part in another incident that might will happen and WN would be protected against the bad press etc in such a case.
As far as I know, Pilots in the US are not allowed to operate pax-planes after their 60th Birthday (For Cargo I am not sure).
So, if Investigations take more than 6 Months he will most propably not return into the cockpit
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The performance figure for landing on contaminated runway in 737-700QRH, are based on "two engine detent reverse thrust"
If the reverse doesn't work, the landing distance, which are advisory by the way, consequently much longer.
Flaps 40, Braking action Medium, 60'000kg/132'000lbs Max Manual Braking, Landing distance = 5955 feet. ( factored by 15%)
How can you land in Midway ?
If the reverse doesn't work, the landing distance, which are advisory by the way, consequently much longer.
Flaps 40, Braking action Medium, 60'000kg/132'000lbs Max Manual Braking, Landing distance = 5955 feet. ( factored by 15%)
How can you land in Midway ?
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Flaps 40, Braking action Medium, 60'000kg/132'000lbs Max Manual Braking, Landing distance = 5955 feet. ( factored by 15%)
What happens during an attempt to activate the thrust reversers if for some reason the weight of the plane is off the wheels? Such as, the pilot attempts to engage the reversers during a bounce? Do they just open when the weight settles, or do they have to be cycled closed and back open again?
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arewenearlythereyet?
Well my friend, I guess you better get your hat out and start eating.
FYI, I’ve got more time on wide bodies than I have on any version of MS Flight Simulator. What’s wrong with FS players anyway??? As an old guy, I find the hot keys a bit tricky so I’ve asked Santa for a joystick. Think it’ll help?
If you think it's the descent thing to do, then I must confess, I’m not a passenger, I’m not a wannabe, I don’t even play Flight sim all that much, but I am a bona fide ATPL. In fact, I hold three ATPLs (2 active) and 5 Type Ratings, one of which is the B737.
You?
And, let’s not turn this into a “my dogs bigger than your dog” pissing contest. You’re the one with the ‘qualification’ issue, eejit.
There ARE far too many 'pretenders' on this thread, aren’t there? I hope that comment isn’t too far off the mark as far as you’re concerned. You sound like a nice man. A little O.T.T., but we all have our eccentricities.
As I’ve already said, I have no idea what SWAs Auto Brake policy is. Does it take a FS2004 wannabe to ask that kind of question??? Don’t think so. Besides, I'm not a wannabe or a wishiwas.
Having taught several U.S. companies directly from their own SOPs, I can tell you I’ve seen Auto Brake policies that would amaze you. I’ve also read other interesting SOPs that make me wonder about a specific SOP within an SOP and why it’s there? Who’s doing the thinking and decision making on the Flight Deck? The Company, or the crew???
“By raising the matter about autobrakes, Willie Mitty tries to infer that it is possible that Southwest have a policy of not using autobrakes when in fact anyone in this industry who is a B737 pilot, especially those of us who work for companies registered in the first world, know that it would be impossible to even get an AoC if someone were stupid enough to even think of implementing such a policy.”
I’d be careful with statements like that. It IS possible.
AoC???
Look deeper into FAR Part 25 (or JAR 25). What part does Reverse Thrust and Auto Brake play in the AFM landing charts? Okay. Now try your question.
“If Wille Mitty Everlearn is a sim instructor (and we don't mean the Microsoft version) and he comes out with more rubbish such as "... I've been lead to believe that auto braking is more effective and efficient than we humans. Have you heard that as well?" then why does he suppose that I, and no doubt most of my colleagues, who do actually fly and operate these types of aircraft into those types of airports in those kinds of weather conditions, should even try and answer him when anyone who is trained on the B737 will know which autobrake settings are the equivalent to maximum manual braking and which are only a deceleration rate.”
Wow! So, you’re a real hairy ast airline pilot. I'm impressed. You’re so lucky! I bet you get all the girls.
But since you asked, at high speeds, thrust reversers and speed brakes make up approximately 80 percent of the total deceleration capability with brakes providing the remainder. I’d say braking and getting stopped was an issue at Midway. Just a guess….
So did they use reverse to the end as well as manually brake or were they autobrakes 3? Simply questions, simple concerns, in’it??? I’m not rushing anyone to judgment, just askin’ da question.
(Bottom line is none of our business, it’ll all come out in the NTSB wash anyway)
This is a pilot rumour network. Eh? Not wanting to sound uncertain, let me say this, you can’t brake your aircraft as efficiently or effectively as an Auto Brake System. Full stop.
Any more questions, Wally?
“It's bad enough that some media types read these forums and are fooled by the likes of these Walter Mitty's and then raise the topic as though it is learned opinion when in fact it is little more than wittering s of someone who knows a little about something and nothing about a lot. This forum should be for educated debate and not for eejits to make stupid assumptions or statements about why they think they know all the answers already and are prepared to be judge, jury and executioner.”
I don’t have a comment on this paragraph because I agree you. Only what’s implied doesn’t apply to me cause I’m not interested in pointing the finger or blaming the crew. Anyone could end up with the same result under the same circumstances. But you have to be in this industry long enough to know that and you will eventually, so don’t worry about it.
Keep the blue side up. It's been a slice.
Willie Everlearn (some days, I’m not so sure)
P.S. Enjoy the hat! I have to Google Walter Mitty.
Well my friend, I guess you better get your hat out and start eating.
FYI, I’ve got more time on wide bodies than I have on any version of MS Flight Simulator. What’s wrong with FS players anyway??? As an old guy, I find the hot keys a bit tricky so I’ve asked Santa for a joystick. Think it’ll help?
If you think it's the descent thing to do, then I must confess, I’m not a passenger, I’m not a wannabe, I don’t even play Flight sim all that much, but I am a bona fide ATPL. In fact, I hold three ATPLs (2 active) and 5 Type Ratings, one of which is the B737.
You?
And, let’s not turn this into a “my dogs bigger than your dog” pissing contest. You’re the one with the ‘qualification’ issue, eejit.
There ARE far too many 'pretenders' on this thread, aren’t there? I hope that comment isn’t too far off the mark as far as you’re concerned. You sound like a nice man. A little O.T.T., but we all have our eccentricities.
As I’ve already said, I have no idea what SWAs Auto Brake policy is. Does it take a FS2004 wannabe to ask that kind of question??? Don’t think so. Besides, I'm not a wannabe or a wishiwas.
Having taught several U.S. companies directly from their own SOPs, I can tell you I’ve seen Auto Brake policies that would amaze you. I’ve also read other interesting SOPs that make me wonder about a specific SOP within an SOP and why it’s there? Who’s doing the thinking and decision making on the Flight Deck? The Company, or the crew???
“By raising the matter about autobrakes, Willie Mitty tries to infer that it is possible that Southwest have a policy of not using autobrakes when in fact anyone in this industry who is a B737 pilot, especially those of us who work for companies registered in the first world, know that it would be impossible to even get an AoC if someone were stupid enough to even think of implementing such a policy.”
I’d be careful with statements like that. It IS possible.
AoC???
Look deeper into FAR Part 25 (or JAR 25). What part does Reverse Thrust and Auto Brake play in the AFM landing charts? Okay. Now try your question.
“If Wille Mitty Everlearn is a sim instructor (and we don't mean the Microsoft version) and he comes out with more rubbish such as "... I've been lead to believe that auto braking is more effective and efficient than we humans. Have you heard that as well?" then why does he suppose that I, and no doubt most of my colleagues, who do actually fly and operate these types of aircraft into those types of airports in those kinds of weather conditions, should even try and answer him when anyone who is trained on the B737 will know which autobrake settings are the equivalent to maximum manual braking and which are only a deceleration rate.”
Wow! So, you’re a real hairy ast airline pilot. I'm impressed. You’re so lucky! I bet you get all the girls.
But since you asked, at high speeds, thrust reversers and speed brakes make up approximately 80 percent of the total deceleration capability with brakes providing the remainder. I’d say braking and getting stopped was an issue at Midway. Just a guess….
So did they use reverse to the end as well as manually brake or were they autobrakes 3? Simply questions, simple concerns, in’it??? I’m not rushing anyone to judgment, just askin’ da question.
(Bottom line is none of our business, it’ll all come out in the NTSB wash anyway)
This is a pilot rumour network. Eh? Not wanting to sound uncertain, let me say this, you can’t brake your aircraft as efficiently or effectively as an Auto Brake System. Full stop.
Any more questions, Wally?
“It's bad enough that some media types read these forums and are fooled by the likes of these Walter Mitty's and then raise the topic as though it is learned opinion when in fact it is little more than wittering s of someone who knows a little about something and nothing about a lot. This forum should be for educated debate and not for eejits to make stupid assumptions or statements about why they think they know all the answers already and are prepared to be judge, jury and executioner.”
I don’t have a comment on this paragraph because I agree you. Only what’s implied doesn’t apply to me cause I’m not interested in pointing the finger or blaming the crew. Anyone could end up with the same result under the same circumstances. But you have to be in this industry long enough to know that and you will eventually, so don’t worry about it.
Keep the blue side up. It's been a slice.
Willie Everlearn (some days, I’m not so sure)
P.S. Enjoy the hat! I have to Google Walter Mitty.
Last edited by Willie Everlearn; 13th Dec 2005 at 03:24.
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Yo Willieeverlearn
If auto brakes for landing exceed the pilot's capability to brake, why then must the pilot exceed MAX to regain control of braking?
The answer is MAX Auto Brake IS NOT MAXIMUM AVAILABLE BRAKING. Max available braking for landing can only be obtained by manually standing on the brakes. In the 700 you must exceed atobrake pressure by even more than in a 300 to regain manual control.
If auto brakes for landing exceed the pilot's capability to brake, why then must the pilot exceed MAX to regain control of braking?
The answer is MAX Auto Brake IS NOT MAXIMUM AVAILABLE BRAKING. Max available braking for landing can only be obtained by manually standing on the brakes. In the 700 you must exceed atobrake pressure by even more than in a 300 to regain manual control.
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The important point here is that the reason why you would have to be a bone head to even consider not using autobrakes ( are there really airlines that have an option to use them!?), is that the really significant factor is how long it takes to to get the brakes on manually. Boeing says that manual application of brakes usually has a delay of 4-5 sec compared to autobrakes. THis would chew up 1000' of runway.
I hope they selected max autobrakes and full reverse and then tried a max manual brakes after it started to go pear shaped, otherwise things will be sticky.
I hope they selected max autobrakes and full reverse and then tried a max manual brakes after it started to go pear shaped, otherwise things will be sticky.
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1. Are the 737NG the thrust reversers are locked out inflight?
2. If so what does it take to unlock the 737NG thrust reversers?
3. What inter-locks are there before you can get full reverse thrust on the 737NG?
Thanks
2. If so what does it take to unlock the 737NG thrust reversers?
3. What inter-locks are there before you can get full reverse thrust on the 737NG?
Thanks
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smokey762
Thanks for your response.
It seems as though I'm not making myself clear enough on this point. Let me try again?
There have been tests (as you would expect) conducted to analyze the application of braking by both the human and the ABS.
The data revealed that humans, under the full and complete belief they were applying Maximum Manual Braking by pressing as hard as they could (standing on the brakes, that is) that when compared to the ABS, measurements indicated there remained additional Manual Brakes available. Does that imply we can find ourselves in a situation where we 'think' we've applied the maximum available manual braking. I think it does. (But that's me. You may have another interpretation.)
I agree with your comment. However, studies would suggest and validate the ABS to be far more efficient and effective than manual braking. By this I mean the ABS applies a more constant than the human. We tend to adjust or vary pressure over the nano seconds, as we gain a feel for the pedals and braking. (That's what the scientists suggest, not me, I just think it stands to reason so I've accepted their suggestion on this). So it would seem to me an interpretation as to when and how we apply brakes under varying conditions which could prove disasterous. Timing must be everything, eh?
Now, when you bring the ABS setting into the picture, it's a slightly different story. Obviously, deceleration rates for Autobrakes 1 isn't quite the same as with Autobrake 3. Even I understand that. But, I don't recall RTO as a normal setting for landing. And as I've said, I'm not sure most would go with manual brakes over ABS, especially on a contaminated surface.
With the Auto Brake switch set to MAX or RTO, the deceleration values are given as 14 ft/sec/sec at a speed greater than 80 Kts and 12 ft/sec/sec at a speed less than 80 Kts. In both cases (MAX/RTO) the brake pressure application is 3000 psi. The Hydraulic psi lessens with lower Auto Brake settings. I'm curious about any value beyond 3000 psi the human is able to provide. I don't dispute what you say, I'm just wondering how a 3000 psi HYD system supplying 3000 psi to MAX or RTO settings is overridden by the crew? Let me think about that.
I believe, to regain manual control of the braking all you have to do is apply manual brakes during auto braking. (AOM, Vol. 2 Landing Gear System Description) The pilot application of manual brakes does nothing to assist auto braking. My impression is that it simply disarms the auto brake regardless of setting.
Thanks for your response.
It seems as though I'm not making myself clear enough on this point. Let me try again?
There have been tests (as you would expect) conducted to analyze the application of braking by both the human and the ABS.
The data revealed that humans, under the full and complete belief they were applying Maximum Manual Braking by pressing as hard as they could (standing on the brakes, that is) that when compared to the ABS, measurements indicated there remained additional Manual Brakes available. Does that imply we can find ourselves in a situation where we 'think' we've applied the maximum available manual braking. I think it does. (But that's me. You may have another interpretation.)
I agree with your comment. However, studies would suggest and validate the ABS to be far more efficient and effective than manual braking. By this I mean the ABS applies a more constant than the human. We tend to adjust or vary pressure over the nano seconds, as we gain a feel for the pedals and braking. (That's what the scientists suggest, not me, I just think it stands to reason so I've accepted their suggestion on this). So it would seem to me an interpretation as to when and how we apply brakes under varying conditions which could prove disasterous. Timing must be everything, eh?
Now, when you bring the ABS setting into the picture, it's a slightly different story. Obviously, deceleration rates for Autobrakes 1 isn't quite the same as with Autobrake 3. Even I understand that. But, I don't recall RTO as a normal setting for landing. And as I've said, I'm not sure most would go with manual brakes over ABS, especially on a contaminated surface.
With the Auto Brake switch set to MAX or RTO, the deceleration values are given as 14 ft/sec/sec at a speed greater than 80 Kts and 12 ft/sec/sec at a speed less than 80 Kts. In both cases (MAX/RTO) the brake pressure application is 3000 psi. The Hydraulic psi lessens with lower Auto Brake settings. I'm curious about any value beyond 3000 psi the human is able to provide. I don't dispute what you say, I'm just wondering how a 3000 psi HYD system supplying 3000 psi to MAX or RTO settings is overridden by the crew? Let me think about that.
I believe, to regain manual control of the braking all you have to do is apply manual brakes during auto braking. (AOM, Vol. 2 Landing Gear System Description) The pilot application of manual brakes does nothing to assist auto braking. My impression is that it simply disarms the auto brake regardless of setting.
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The important point here is that the reason why you would have to be a bone head to even consider not using autobrakes ( are there really airlines that have an option to use them!?), is that the really significant factor is how long it takes to to get the brakes on manually. Boeing says that manual application of brakes usually has a delay of 4-5 sec compared to autobrakes. THis would chew up 1000' of runway.
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This is amazing! So SWA is more interested in keeping pilots in the "loop" than stopping in the minimum distance, particularly on a contaminated runway?
They had better get that cheque book out to pay a few billion in compensation, that sort of policy is dangerous.
They had better get that cheque book out to pay a few billion in compensation, that sort of policy is dangerous.
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This is amazing! So SWA is more interested in keeping pilots in the "loop" than stopping in the minimum distance, particularly on a contaminated runway?
At the request of the Safety Board's Airplane Performance Group, Boeing ran stopping
distance simulations for this accident wherein maximum, medium, and minimum 737 autobrake
applications, as well as maximum manual brake applications, were simulated for wet runway
conditions after the 182-knot touchdown. These data indicate that the accident airplane would
have required about 5,000 feet of runway length after touchdown to stop using maximum
autobrakes and about 4,700 feet of runway length after touchdown to stop using maximum
manual brakes.
distance simulations for this accident wherein maximum, medium, and minimum 737 autobrake
applications, as well as maximum manual brake applications, were simulated for wet runway
conditions after the 182-knot touchdown. These data indicate that the accident airplane would
have required about 5,000 feet of runway length after touchdown to stop using maximum
autobrakes and about 4,700 feet of runway length after touchdown to stop using maximum
manual brakes.
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For me - as a pax and enthusiast - there are only 2 explanations for what I get to read here
a) after all these years in an industry full of rules, regulations and safety concerns still nobody has enough data on performance on contaminated runways, especially on performance difference between manual and auto braking
b) there is not much difference between the two methods and it is at pilots (airline?) discretion, especially with the possibility of using both (with timing based on experience being crucial)
I hope someone can confirm it's b) or some c) I have overlooked
a) after all these years in an industry full of rules, regulations and safety concerns still nobody has enough data on performance on contaminated runways, especially on performance difference between manual and auto braking
b) there is not much difference between the two methods and it is at pilots (airline?) discretion, especially with the possibility of using both (with timing based on experience being crucial)
I hope someone can confirm it's b) or some c) I have overlooked
For the professional pilots in this forum and those who hope to join the industry as such, then downloading and viewing the presentation on approach and landing is a ‘must do’ activity.
Also print the notes and keep a copy in your Nav bag for reference.
Most of the speculative issues discussed above are covered and there are additional references and links.
Of interest and relevance in this thread are the quotes:
“Attempts to land on contaminated runways involve considerable risk and should be avoided whenever possible.”
“The friction level of a Concrete runway is not as good as ‘black top’ Tarmac, which is not as good as ‘high friction course’ Tarmac. Beware of rubber deposits on all surfaces particularly on wet runways.”
The last one is of particular interest as I recall that Midway is all concrete, and according to the last Google photo, there were considerable and lengthy rubber deposits on both ends of runway 13/31.
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Airspeed and Upwardness
Also print the notes and keep a copy in your Nav bag for reference.
Most of the speculative issues discussed above are covered and there are additional references and links.
Of interest and relevance in this thread are the quotes:
“Attempts to land on contaminated runways involve considerable risk and should be avoided whenever possible.”
“The friction level of a Concrete runway is not as good as ‘black top’ Tarmac, which is not as good as ‘high friction course’ Tarmac. Beware of rubber deposits on all surfaces particularly on wet runways.”
The last one is of particular interest as I recall that Midway is all concrete, and according to the last Google photo, there were considerable and lengthy rubber deposits on both ends of runway 13/31.
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Airspeed and Upwardness