AA Crash Jamaica
Originally Posted by Beach Nut
26 so far for Air Canada (1983 Cincinnati DC-9 fire was the last one).
Originally Posted by bearfoil
Marketing: the Art of celebrating denial to promote a product.
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American Airlines' training program was reviewed numerous times by the manufacturer prior to the accident
1 week of jumpseat flying on the line and a report/debrief at the end of it is almost worthless. The don't look at why you do what you do. They don't look at your mod status, your FDA data, your crew experience/history, your route structure, your .....etc.. The only value you can expect the visit is havig somebody there from AI or Boeing or Canadair or EMB or ...to answer questions directly.
If they're comments/feedback on your operation make any difference to your operation in the final analysis, then you must really be screwing things up. Manufacturer's visits are usually nothing more than a cloaked marketing ploy.
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Mr. Nnc0, my point was, had there been a real problem with AA's A300 training program pre-accident, it should have been pointed out and corrected then, not after the fact.
The finger pointing that began in earnest post-accident shows how little the principals were connected to reality. It was as if the lawyer speak took precedence over documented history and ultimately, the truth, where both Airbus and American Airlines might possibly share in the blame.
The finger pointing that began in earnest post-accident shows how little the principals were connected to reality. It was as if the lawyer speak took precedence over documented history and ultimately, the truth, where both Airbus and American Airlines might possibly share in the blame.
Good writers have always managed to make do without those wretched cueballs called smileys
when I write it's barely understandable by the general public trust me
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airline_safety_one_year_table
Only SW higher rated than AA amongst U.S. carriers(yeah, I was surprised).
Airline accident ratings
Rated SW and Delta higher than AA amongst U.S. carriers. Worldwide only Lufthansa(3rd) ranks higher than AA(4th).
Only SW higher rated than AA amongst U.S. carriers(yeah, I was surprised).
Airline accident ratings
Rated SW and Delta higher than AA amongst U.S. carriers. Worldwide only Lufthansa(3rd) ranks higher than AA(4th).
The discussion has drifted into ‘mechanistic and reductionist thinking’, where evidence from one context is applied to another or used to pursue a cause and effect solution unsuitable for highly complex situations. This tends to restrict a much needed wider view of the world, a wider view of aviation safety, a wider view of accidents, and thereby an opportunity to learn from the misfortunes of others.
Many would argue ‘wait for the report’, but accident investigations rarely are able to identify all aspects or contributions to the ‘cause’. Sometimes evidence is un available, insufficient or unreliable to draw conclusions from, or in many cases such as with human error, it remains unknown even to the perpetrators of ‘unsafe acts’.
Thus, there is merit in exchanging informed speculation, where similar issues can be aired, what if’s explored, and best practices exchanged. These may not relate directly to this accident, but might just avoid another – the primary aim of any formal investigation.
As an example, there was an exchange of the pros and cons of using HUD. If in this accident the lateral transition from an offset LOC in restricted visibility due to heavy rain, and with a tailwind which might have equated to an additional 1.5 deg ‘air-mass’ flight-path, perhaps the pilot was experiencing high workload in a restricted timeframe. This might not be determined beyond supposition by an investigation. More likely other pilots could comment on similar experiences, good or bad, not just quoting a HUD ‘sales’ pitch, but providing first-hand examples with reasoned argument; there may be something which we can learn, so that we might continue to operate safely.
This forum should not degenerate into a ‘bad apple’ – person (or organisation) model of safety, this can only conclude with blame which contributes nothing.
We have to look at the wider issues in complex scenarios often encountered in modern operations.
This forum should be generating a learning culture, lest such an accident might happen to us, irrespective of what statistics or self opinion might indicate.
Many would argue ‘wait for the report’, but accident investigations rarely are able to identify all aspects or contributions to the ‘cause’. Sometimes evidence is un available, insufficient or unreliable to draw conclusions from, or in many cases such as with human error, it remains unknown even to the perpetrators of ‘unsafe acts’.
Thus, there is merit in exchanging informed speculation, where similar issues can be aired, what if’s explored, and best practices exchanged. These may not relate directly to this accident, but might just avoid another – the primary aim of any formal investigation.
As an example, there was an exchange of the pros and cons of using HUD. If in this accident the lateral transition from an offset LOC in restricted visibility due to heavy rain, and with a tailwind which might have equated to an additional 1.5 deg ‘air-mass’ flight-path, perhaps the pilot was experiencing high workload in a restricted timeframe. This might not be determined beyond supposition by an investigation. More likely other pilots could comment on similar experiences, good or bad, not just quoting a HUD ‘sales’ pitch, but providing first-hand examples with reasoned argument; there may be something which we can learn, so that we might continue to operate safely.
This forum should not degenerate into a ‘bad apple’ – person (or organisation) model of safety, this can only conclude with blame which contributes nothing.
We have to look at the wider issues in complex scenarios often encountered in modern operations.
This forum should be generating a learning culture, lest such an accident might happen to us, irrespective of what statistics or self opinion might indicate.
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Healthy discussion
Damn, Alf, well said!
The folks who do not desire to professionally discuss and analyze incidents such the this topic's...well, don't view the topic!
But, for those professional pilots, investigators, academics or any interested party with something to say should be allowed - indeed encourged - to opine as they see fit.
Oh, H-E-double-hockey-sticks - Alf said it better than this aged jock ever could.
The folks who do not desire to professionally discuss and analyze incidents such the this topic's...well, don't view the topic!
But, for those professional pilots, investigators, academics or any interested party with something to say should be allowed - indeed encourged - to opine as they see fit.
Oh, H-E-double-hockey-sticks - Alf said it better than this aged jock ever could.
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NTSB shifts role: ADVOCATE for US operator & manufacturer
A few slots earlier, Alf5071h mentioned:
A separate concern is NTSB's role in foreign investigations (ICAO Annex 13) involving US manufacturer (and now a US operator). Sometimes the NTSB seemed forced to act as ADVOCATE, abandoning any critical analysis of the US organization, instead backing their distracting red-herring assertions. This you can see in the NTSB's comments to the investigating authority, eg:
"... ‘wait for the report’, but accident investigations rarely ... identify all aspects ... the ‘cause’ ... evidence is unavailable, insufficient or unreliable to draw conclusions ..."
The NTSB has itself been unreliable, or inconsistent, in its investigations re' the operator, FAA's Sotuthwest Region, & ALAR. NTSB seemed to block FSF's ALAR efforts, eg NTSB's botched investigation of DEN06IA051 . Prior mishap investigations had built a history on that operator and their "regulator" (history behind NTSB Safety Recommendation A-01-69, still classified "Open--Unacceptable Response".See AA873 / 5Jun96 ABQ FTW96IA237
http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001208X05961&key=1
See AA699 / 6Feb97, DCA97LA027 accident in St. John’s, Antigua,
http://www.ntsb.gov/ntsb/brief2.asp?ev_id=20001208X07395&ntsbno=DCA97LA027&akey=1
See AA1115 / 21Nov04, at DEN DEN05IA02
http://www.ntsb.gov/ntsb/brief.asp?ev_id=20041122X01849&key=1
See web video of AA / Saturday 13Aug05, MD80 wing-tip scrape (and tail strike?) during landing touchdown at, RWY 7R, Las Vegas, NV
ALAR = Approach and Landing Accident Reductionhttp://www.ntsb.gov/ntsb/brief.asp?ev_id=20001208X05961&key=1
See AA699 / 6Feb97, DCA97LA027 accident in St. John’s, Antigua,
http://www.ntsb.gov/ntsb/brief2.asp?ev_id=20001208X07395&ntsbno=DCA97LA027&akey=1
See AA1115 / 21Nov04, at DEN DEN05IA02
http://www.ntsb.gov/ntsb/brief.asp?ev_id=20041122X01849&key=1
See web video of AA / Saturday 13Aug05, MD80 wing-tip scrape (and tail strike?) during landing touchdown at, RWY 7R, Las Vegas, NV
This ALAR effort includes
-- ARC [Abnormal Rwy Contact], Hard Ldg, Tailstrike, Wingtip strike, and
-- RE [Rwy Excursion]
= = = = = = = = = -- ARC [Abnormal Rwy Contact], Hard Ldg, Tailstrike, Wingtip strike, and
-- RE [Rwy Excursion]
A separate concern is NTSB's role in foreign investigations (ICAO Annex 13) involving US manufacturer (and now a US operator). Sometimes the NTSB seemed forced to act as ADVOCATE, abandoning any critical analysis of the US organization, instead backing their distracting red-herring assertions. This you can see in the NTSB's comments to the investigating authority, eg:
-- after SAS751 / 27Dec91, MD81 OY-KHO, SHK's Report # C 1993:57, Appendix 6 "NTSB's Comments on Draft Final" (backing DAC's assertions rather than acting as an "independent" safety board).
-- after MI185 / 17Dec97, B737 9V-TRF, NTSC's Accident Report, Appendix N, " USA Accredited Representative's Comments on Draft Final Report", where Jim Hall shifts role to more of a defense attorney for TBC, forgetting any mention of 70-years of earlier mysterious airliner upsets.
*
-- after MI185 / 17Dec97, B737 9V-TRF, NTSC's Accident Report, Appendix N, " USA Accredited Representative's Comments on Draft Final Report", where Jim Hall shifts role to more of a defense attorney for TBC, forgetting any mention of 70-years of earlier mysterious airliner upsets.
Last edited by IGh; 18th Jan 2010 at 18:36.
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Not a HUD salesperson
If in this accident the lateral transition from an offset LOC in restricted visibility due to heavy rain, and with a tailwind which might have equated to an additional 1.5 deg ‘air-mass’ flight-path, perhaps the pilot was experiencing high workload in a restricted timeframe. This might not be determined beyond supposition by an investigation. More likely other pilots could comment on similar experiences, good or bad, not just quoting a HUD ‘sales’ pitch, but providing first-hand examples with reasoned argument; there may be something which we can learn, so that we might continue to operate safely.
Alf -- do you have extensive experience with HUD?
What is meant by "..might have equated to an additional 1.5 deg 'air-mass' flight-path"?
None of my HUD-posts were intended as sales pitches. I was simply trying to explain how the GS reference line and the airspeed deviation cues
are presented in the combiner.
While the GS reference line is "anchored" to the airplane, the displayed image is conformal to planet earth. I'm not following the "additional 1.5 deg air-mass" part. Would you mind elaborating?
Thanks,
Z
Zeffy, no criticism of your views on HUD. Your experience appears to be more recent than my dated exposure might be.
Re additional 1.5 deg 'air-mass' flight-path
Flying a stabilised approach on a ground referenced path (ILS GS) the aircraft maintains a constant rate of descent, e.g. in still air 148 kt, very approximately 750ft/min.
In a tailwind the stable rate of descent will increase - 163 kt Grnd Spd (-15kt wind), say 850ft/min.
To provide the higher rate of descent the attitude has to be more nose down – no difference between HUD / non HUD.
The ground reference flight-path remains the same, but if the flight path is referenced to the airmass (moving with you in a tailwind), then the airmass flight-path has to be steeper. My quick rule of thumb (approximate and varies with aircraft type), equates 10 kts to 1 deg.
So far (sorry - sucking eggs), this is probably of little practical value, other than to cue thoughts about the differences in a situation during a tailwind approach – but thinking about the differences is important.
The point of this observation is that in the HUD, the aircraft attitude reference will be much lower, perhaps unusually so (1:1 world relationship), such that the interpretation/unfamiliarity of this situation might require higher workload – it requires a plan – thinking ahead.
The offset LOC could be of greater concern. The approach was night/IMC; it is reported that the PF was using HUD (manual or monitoring autoflight?). During the approach the HUD FD would have been centered, however when visual and aligning with the runway centerline, the LOC component of the FD has to be ignored; the GS can still be used.
If the HUD symbol is a combined cue (circle/donut), then split axis flight can be very demanding. Also, there is a potentially confusing situation depending where the LOC axis crosses the runway centerline – threshold, or earlier at 200ft. The latter might result in flying through the centerline requiring a roll reversal. This too could increase workload, particularly in the shorter time scale than normal due to the tailwind – more bank angle required.
Considering the vertical; whilst the ILS GS could provide information, the optimum HUD mode might be visual / ground referenced approach path (as discussed previously). Changing modes (either manually or just mentally), IMHO requires great concentration.
The normal ‘every-day’ situation might be to transition from IMC to VMC without changing the way in which the HUD is used or the operating mode – the flare can be completed using the same display (FD) as for the approach.
However, with an offset LOC, even if the flare mode was working, part of the display has to be ignored. The main guidance symbol may not be aligned with the runway, presenting a different mental picture of the situation than the norm – a recipe for confusion, distraction, high workload.
Hence, in addressing a previous question ‘why didn’t the crew see the threshold / touchdown zone’, then the PF could be ‘maxed out’ flying the HUD, with little or no spare mental attention for updating the situation – and it was dark, heavy rain, and possibly poor lighting.
Of course, the above is supposition, IMHO justifiable, supported by the explanation of the difficulties of using HUD in a demanding situation.
Will these aspect be considered be in any formal report? I wait with interest.
Re additional 1.5 deg 'air-mass' flight-path
Flying a stabilised approach on a ground referenced path (ILS GS) the aircraft maintains a constant rate of descent, e.g. in still air 148 kt, very approximately 750ft/min.
In a tailwind the stable rate of descent will increase - 163 kt Grnd Spd (-15kt wind), say 850ft/min.
To provide the higher rate of descent the attitude has to be more nose down – no difference between HUD / non HUD.
The ground reference flight-path remains the same, but if the flight path is referenced to the airmass (moving with you in a tailwind), then the airmass flight-path has to be steeper. My quick rule of thumb (approximate and varies with aircraft type), equates 10 kts to 1 deg.
So far (sorry - sucking eggs), this is probably of little practical value, other than to cue thoughts about the differences in a situation during a tailwind approach – but thinking about the differences is important.
The point of this observation is that in the HUD, the aircraft attitude reference will be much lower, perhaps unusually so (1:1 world relationship), such that the interpretation/unfamiliarity of this situation might require higher workload – it requires a plan – thinking ahead.
The offset LOC could be of greater concern. The approach was night/IMC; it is reported that the PF was using HUD (manual or monitoring autoflight?). During the approach the HUD FD would have been centered, however when visual and aligning with the runway centerline, the LOC component of the FD has to be ignored; the GS can still be used.
If the HUD symbol is a combined cue (circle/donut), then split axis flight can be very demanding. Also, there is a potentially confusing situation depending where the LOC axis crosses the runway centerline – threshold, or earlier at 200ft. The latter might result in flying through the centerline requiring a roll reversal. This too could increase workload, particularly in the shorter time scale than normal due to the tailwind – more bank angle required.
Considering the vertical; whilst the ILS GS could provide information, the optimum HUD mode might be visual / ground referenced approach path (as discussed previously). Changing modes (either manually or just mentally), IMHO requires great concentration.
The normal ‘every-day’ situation might be to transition from IMC to VMC without changing the way in which the HUD is used or the operating mode – the flare can be completed using the same display (FD) as for the approach.
However, with an offset LOC, even if the flare mode was working, part of the display has to be ignored. The main guidance symbol may not be aligned with the runway, presenting a different mental picture of the situation than the norm – a recipe for confusion, distraction, high workload.
Hence, in addressing a previous question ‘why didn’t the crew see the threshold / touchdown zone’, then the PF could be ‘maxed out’ flying the HUD, with little or no spare mental attention for updating the situation – and it was dark, heavy rain, and possibly poor lighting.
Of course, the above is supposition, IMHO justifiable, supported by the explanation of the difficulties of using HUD in a demanding situation.
Will these aspect be considered be in any formal report? I wait with interest.
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Huh?
Alf, you lost me on this one. Did you address Zeffy's question in your treatise somewhere?
With all due respect, I am just looking to understand this better (I don't fly anything currently with a HUD). In my prehistoric life, I recall the HUD taking into account AOA and winds and, well all flight parameters. I don't see anything special with this case with regard to cockpit instrumentation...just in decision making.
Thanks
With all due respect, I am just looking to understand this better (I don't fly anything currently with a HUD). In my prehistoric life, I recall the HUD taking into account AOA and winds and, well all flight parameters. I don't see anything special with this case with regard to cockpit instrumentation...just in decision making.
Thanks
SK8TRBOI The airmass flight path aspect may be an old view of HUD and not applicable to the newer systems – an irrelevancy.
It may be clearer just to state that in a tailwind, because the aircraft is going faster, the nose has to be lower in order to maintain the ILS GS, this gives a higher rate of descent. Although this is stating the obvious, these aspects have to be deduced from HUD symbols – not identical to conventional instruments. Thus there may be a higher workload when using HUD.
HUDs do not take ‘all of that’ into account. They can display much more information, and in differing formats to ADIs. If this information is not managed - workload / self discipline / planning, then in stressful or time critical situations the pilot may have less capability to attend to other aspects of flight.
The LOC issue may be clearer by considering an attempted head-down landing using a conventional flight director with a flare mode. With the LOC aligned with the runway the task is to keep the FD centred.
With an offset LOC the lateral guidance cue has to be ignored whilst flaring in pitch.
A split cue FD (cross wires) may be an easier task than with a single cue (combined pitch/roll) FD, many HUDs have combined cue FDs. This could be a demanding mental task which increases workload and decreases the ability to focus attention elsewhere.
Thus possibly as a result of routine HUD use for landing (straight-in ILS), crews are becoming ‘technology dependent’; it may be very difficult to break this normal habit – flaring with HUD FD, if the ILS is not straight-in. Combine this change in task with poor weather and low visibility, and a tailwind, these aspects could contribute to tunnel vision – HUD fixation.
I would argue that crews have to think out these issues in advance, particularly when using HUD in uncommon situations, and focus their risk assessment on adverse combinations of landing factors so that an alternative landing option can be selected.
It may be clearer just to state that in a tailwind, because the aircraft is going faster, the nose has to be lower in order to maintain the ILS GS, this gives a higher rate of descent. Although this is stating the obvious, these aspects have to be deduced from HUD symbols – not identical to conventional instruments. Thus there may be a higher workload when using HUD.
HUDs do not take ‘all of that’ into account. They can display much more information, and in differing formats to ADIs. If this information is not managed - workload / self discipline / planning, then in stressful or time critical situations the pilot may have less capability to attend to other aspects of flight.
The LOC issue may be clearer by considering an attempted head-down landing using a conventional flight director with a flare mode. With the LOC aligned with the runway the task is to keep the FD centred.
With an offset LOC the lateral guidance cue has to be ignored whilst flaring in pitch.
A split cue FD (cross wires) may be an easier task than with a single cue (combined pitch/roll) FD, many HUDs have combined cue FDs. This could be a demanding mental task which increases workload and decreases the ability to focus attention elsewhere.
Thus possibly as a result of routine HUD use for landing (straight-in ILS), crews are becoming ‘technology dependent’; it may be very difficult to break this normal habit – flaring with HUD FD, if the ILS is not straight-in. Combine this change in task with poor weather and low visibility, and a tailwind, these aspects could contribute to tunnel vision – HUD fixation.
I would argue that crews have to think out these issues in advance, particularly when using HUD in uncommon situations, and focus their risk assessment on adverse combinations of landing factors so that an alternative landing option can be selected.
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HUD
Ok, Alf, fair 'nuff - much good info in your response, thank you for that.
I've got the approach plates in front of me and I'm trying to 'visualize' what I'd do, where I'd be and when, given the circumstances of that night. The biggest problem I'm having, of course, is understanding how that offset at KIN is depicted on a HUD - I'm very curious now as to how that'd look.
Now I gotta go bug a 'friend' who can wrangle me 30 min. or so of sim time on a NG (probably at 0300!!) because now I have to see for myself how this works, and how it looks.
Thanks!
I've got the approach plates in front of me and I'm trying to 'visualize' what I'd do, where I'd be and when, given the circumstances of that night. The biggest problem I'm having, of course, is understanding how that offset at KIN is depicted on a HUD - I'm very curious now as to how that'd look.
Now I gotta go bug a 'friend' who can wrangle me 30 min. or so of sim time on a NG (probably at 0300!!) because now I have to see for myself how this works, and how it looks.
Thanks!
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Thanks for expanding the points, alf,
Not really much pilot "deduction" involved with respect to pitch attitude -- the pilot's primary focus is far more likely to be on the Flight Path Vector which shows where the airplane is going irrespective of configuration or attitude. For that reason, the HUD "boresight" cue (the direct attitude reference) is likely to almost "disappear" due to natural tunnel-vision tendencies under higher workloads.
Reports have indicated that the runway was in view from 700-1000 AGL -- so more than 2 miles from the threshold if on GS.
That would assume that the FD cue remained in view; we don't know that yet. But the use or non-use of the FD may lead to questions about the need to de-clutter the HUD in the last mile or two to the runway when the LOC is offset. Unlike a conventional ILS where the FD cue can remain in view until touchdown, (and as you've indicated) the LOC and therefore any lateral FD guidance would become a distraction close to the runway.
My personal HUD experience is limited to the RockwellCollins HGS.
I've been drilling around the internet for some videos or descriptions of how the Marconi HUD works. Does it have automatic de-clutter modes -- e.g., are the airspeed and altitude tapes dropped once the GS is captured or once in final the landing configuration?
Is it fairly easy to cancel the Marconi HUD FD guidance on an ILS and continue with a visual approach mode? Or for example, is it also necessary to de-select the ILS frequency?
The HUD's Flight Path Vector, GS reference line and airspeed deviation cues can remain valuable tools even when the FD is deselected. It's not necessary or even preferable to stow the HUD for an offset LOC; but as you say, the offset LOC and the plans to deal with it have to be part of the briefing.
`
It may be clearer just to state that in a tailwind, because the aircraft is going faster, the nose has to be lower in order to maintain the ILS GS, this gives a higher rate of descent. Although this is stating the obvious, these aspects have to be deduced from HUD symbols – not identical to conventional instruments. Thus there may be a higher workload when using HUD.
Reports have indicated that the runway was in view from 700-1000 AGL -- so more than 2 miles from the threshold if on GS.
With an offset LOC the lateral guidance cue has to be ignored whilst flaring in pitch.
I would argue that crews have to think out these issues in advance, particularly when using HUD in uncommon situations, and focus their risk assessment on adverse combinations of landing factors so that an alternative landing option can be selected.
I've been drilling around the internet for some videos or descriptions of how the Marconi HUD works. Does it have automatic de-clutter modes -- e.g., are the airspeed and altitude tapes dropped once the GS is captured or once in final the landing configuration?
Is it fairly easy to cancel the Marconi HUD FD guidance on an ILS and continue with a visual approach mode? Or for example, is it also necessary to de-select the ILS frequency?
The HUD's Flight Path Vector, GS reference line and airspeed deviation cues can remain valuable tools even when the FD is deselected. It's not necessary or even preferable to stow the HUD for an offset LOC; but as you say, the offset LOC and the plans to deal with it have to be part of the briefing.
`
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On another aviation BB, I read the following post from a retired AA CA:
He was not voicing any opinions about the accident, just responding to some questions about the factors involved.
"According to....the Allied Pilots Union discussion board; they were at or near max landing wt. The guys who fly the 737 into that airport say that they always tanker maximum fuel inbound as it is more expensive at that location.
"Also...the pilots who fly that model of the 737 say that it is a very squirrely airplane on wet runways. The airplane has been stretched significantly from it's orginal configuration....yet the landing gear and fuselage remain in the same close proximity to the surface. Because of the lengthened fuselage, normal approach speed and pitch attitude for the earlier versions would result in a tail strike nearly every time.
"Therefore Boeing added 11 kts to the standard approach speed in order to keep the nose pitch attitude lower and prevent a tail strike. Simply stated....this model approaches faster, flatter and touches down faster to compensate for a poor design. Also they say that rudder control is more limited after landing...much as the MD-80 rudder control was when compared with shorter versions of the DC-9."
"Therefore Boeing added 11 kts to the standard approach speed in order to keep the nose pitch attitude lower and prevent a tail strike. Simply stated....this model approaches faster, flatter and touches down faster to compensate for a poor design. Also they say that rudder control is more limited after landing...much as the MD-80 rudder control was when compared with shorter versions of the DC-9."
He was not voicing any opinions about the accident, just responding to some questions about the factors involved.
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@kappa
Compare to Post 165 of this thread on the -800 series:
http://www.pprune.org/5402907-post165.html
http://www.pprune.org/rumours-news/3...ml#post5402907
Edit: Change subject to relate to previous post and fix links.
http://www.pprune.org/5402907-post165.html
http://www.pprune.org/rumours-news/3...ml#post5402907
Edit: Change subject to relate to previous post and fix links.
Last edited by fotoguzzi; 22nd Jan 2010 at 06:36.
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Kappa - fact - the 737 Vref speeds for Flaps 30 are 1.3 Vso. Vref for Flaps 40 is 1.25 Vso.
The reality, at least for Flaps 40 Vref, is that the Vref speeds are artificially lower than typical Vref speeds (1.25 Vso instead of 1.3 Vso). That's exactly 180 degrees from the post you reposted.
The plane is 'hot'. It's from the stall speeds, multiplied by either 1.25 or 1.3 Vso, and not some 'added' pad. Unless the stall speeds are deliberately(artificially, ie 'pencil whipped') increased, which I doubt.
Never heard anyone mention rudder issues and havn't observed it either.
The report stated Vref was 148 kts. That is Vref for Flaps 30 @ max landing weight. The initial reports state that the landing was at Vref, and not some Vref + number.
The reality, at least for Flaps 40 Vref, is that the Vref speeds are artificially lower than typical Vref speeds (1.25 Vso instead of 1.3 Vso). That's exactly 180 degrees from the post you reposted.
The plane is 'hot'. It's from the stall speeds, multiplied by either 1.25 or 1.3 Vso, and not some 'added' pad. Unless the stall speeds are deliberately(artificially, ie 'pencil whipped') increased, which I doubt.
Never heard anyone mention rudder issues and havn't observed it either.
The report stated Vref was 148 kts. That is Vref for Flaps 30 @ max landing weight. The initial reports state that the landing was at Vref, and not some Vref + number.