Your landing or mine - the captain's ultimate responsibility

[donpizmeov]

Chuck,

From the A343 holy book. For an aircraft at MLW, flaps full, medium autobrakes, 1/2inch standing water. (From the book: Autoland landing distance with autobrake)

Factored LDR, 1/2 inch water, 10kts tail wind = 2722m
With 4 reversers operating= 2477m

Thats from landing threshold to point of stop.

Unfactored for same conditions as above: (from book:the actual landing distance to come to a complete stop from a point 50' above the landing surface. No margin is included in this distance).

2063m (this is with operating reversers). 1664m nil wind.

(Used 10kts tail as I am too lazy to work out the 5kt factor, used max landing weight as most limiting case)

9000' x 0.305= 2745m. Don't know what the distance beyond the glidepath was.

Don

[J430]

Don

I think the answer is right there. And I am a novice. From the book, reversers working (some many second later).......they were skating on ice way to thin, with heated blades!

Who likes using the whole strip, nose up to the brbe wire so to speak. Not me. What about you Chuck?

Maybe I am wrong.

J

[Chimbu chuckles]

Thanks Don...much better to use airbus figures than to try and massage, and draw conclusions from, my 767 figures.

Lets assume for simplicity sake that the increased LDR is linear between nill wind and -10kts (tailwind)

From your figures that gives 6150' [(2063m+1664m)/2 (3.3)] unfactored (all reversers working). Close enough to the figure quoted earlier in the thread (6600') for govt workers.

6150 x 1.67 = 10270'

Lets assume nil wind...fighting hard to give the crew the benefit of all doubt.

1664m x 3.3 = 5490' x 1.67 = 9170'

Of course in my last post the 11000' figure (6614x 1.67) was correct and I should not have increased that figure anymore because the basic figure is already for 'poor' braking action thus requires no further factoring after 1.67. Post edited accordingly.

They still had no legal basis for starting an approach.

[Gnadenburg]

Can someone from the elite Airbus brotherhood explain to me why Chimbu is using the dry conditions, pre-dispatch 1.67 factor to an airborne, contaminated runway scenario?

1.15 contaminated rwy factor incidentally.

[Gnadenburg]

Fact is the 'good old days' are over and finished...pilots who have entered the system in the last 10-15 yrs will never gain those skills because the system and aircraft design don't allow them. That being the case you're just gonna scare people witless doing it in aircraft that lack the flexibility to do it easily, even though an 'expanded green band' still makes it possible.

Sorry Chimbu. We will never agree. I see you & your ilk as apologists for a deterioration of elemental aviation skills. Glass technology can hide this for a whole career. But sadly, it can also fatally expose it- about once in 5 years on Airbus aircraft.

[Chimbu chuckles]

Whose using dry figures?

Don's figures were for contaminated.

'Poor' reported braking action refers to braking action on 'wet ice' in the Boeing QRH. I assume something similar would be the certification process in an Airbus.

I would be just fascinated to see a reference for not factoring LDR in normal ops...either before dispatch or after.

You might view me as an appologist, although the check and training dept here would find that amusing to say the least. I think you're stuck in the past...technology has moved on and, like it or not, the system relies on that technology.

[donpizmeov]

I think the main point here is, that if the guys had been able to hit the tarmac in the correct spot, we would not be reading about it. As they would have stopped with some 300m remaining, using medium autobraking. If they they had used max manual braking after touchdown in the correct spot, they would have 700m remaining. All this at Max landing weight (not sure what weight they were at), and 10kts tailwind (twice what has been mentioned). I think this shows the importance of stabilised approaches, and maintaining the correct touchdown point, rather than the implications of pre and post dispatch performance figures. This accident was preventable right up to the point of touchdown.

A good lesson for all of us I should think.

Don

[fistfokker]

Can someone from the elite Airbus brotherhood explain to me why Chimbu is using the dry conditions, pre-dispatch 1.67 factor to an airborne, contaminated runway scenario?
1.15 contaminated rwy factor incidentally.

While not claiming to be an elite of Airbus brotherhood (I hate the heap of s**t but am forced to fly it to date) in my experience many Airbus pilots believe the 1.67 factor (dry) + the .15 (wet) only applies pre-dispatch and that once dispatched only the FCOM/QRH actual landing distance figure need be applied. In Aus the factor must always be applied unless in an emergency. NOT abnormal or Company convenience but EMERGENCY. Contaminated runway landings are not allowed. While conceding that other contracting states may permit contaminated runway landings the factor for this would always be additional to Dry runway factored distance unless in an emergency.
Hence this would explain CC's use of DRY runway conditions as the starting point.
I don't fancy explaining to ATSB why I ran of the end of the runway at Hamilton Island, for example, because the flaps had seized at Flap1, the QRH said I only had to add 10% (not actual but for example) to the actual dry landing distance but I had the fuel on board to divert to Townsville.

J* pilots should Harden The F*** Up frankly. Try circling off the completion of that profile at 500' like the mugs used to make us do a decade ago.

I think you may find that world wide attitudes have changed to ten years ago. The type of approach you have described in RPT Jet transport is a sure fire recipe for CFIT and should be actively discouraged. Sadly it does seem to exist still in some circles. "I can do it" is a common phrase used in CRM courses as an alarm bell. I know if I am sitting in the back I would like to think the operating crew would utilise a runway aligned approach, with automatics, in preference to a hand flown, raw data, minimum use of any available resources, circling apprach the way Airbus and ex AN pilots advocate when there is so much more available to assist with a safe and efficient outcome.
The fact that so many relatively minor systems failures on Airbus aicraft may require Raw data, Hand Flown Approaches using manual thrust, in this day and age, compared to equivalent Boeing aircraft, is supportive of my view that the the Airbus family is an accident looking for somewhere to take place, and should never have been certified to carry fare paying members of the unsuspecting public.
You may think you are cleverer than the average Jet* pilot but I can assure you, none of us would contemplate circling in the dark at 500ft if there were any other alternative. And yes I have operated in an environment like that in the past in steam driven jets. I can do it, I just choose not to. The place to practice that kind of thing is in the simulator, in a training environment, NOT in the aircraft in normal operations, just in case some idiot check pilot wants to see it done in real life or the sim on check day.

[Chimbu chuckles]

Further to the above I quote the Boeing QRH, Performance in Flight-Text.

These values are actual distances and do not include the 1.67 regulatory factor. Therefore, they cannot be used to determine the dispatch required landing field length.

That would indicate that it applies everywhere not just Australia.

As Toronto was the dispatched destination those factors must apply. I would hate to try and argue to the ATSB or in a court of Law that they do not apply in all cases other than an emergency. It is my belief that they do apply.

Quite frankly I find it a little strange that we factor thus when the aeroplane is perfectly serviceable but need no factoring, legally, when the aircraft is in a degraded state...that doesn't mean of course that good airmanship or company SOP don't require factoring in an emergency.

Don I agree that if they did it all perfectly, or even reasonably, they would have stopped in the LDA...but I remain sceptical that the approach was legal.

These are the sorts of accidents that, if anything was required at all, keep me in the QRH to ensure I am aware what is 1/. possible and 2/. legal.

[Gnadenburg]

Chimbu

I have no idea what you are talking about. You further compound my misunderstanding by meshing Boeing with Airbus, metres with feet, pre-dispatch with dispatch, dry with wet with contaminated. On top of this little basket case is the fact that the WX Toronto pre-dispatch didn't forecast a contaminated runway as this was caused by a severe thunderstorms.

[donpizmeov]

REQUIRED LANDING DISTANCE

[Chimbu chuckles]

Really? I thought it was pretty clear.

I never mentioned or used dry figures...they are all either contaminated figures from Don's A343 QRH or the figures from the accident investigation (I assume Transport Canada calculated the LDR with respect to the contaminated state of the runway). The only other references were to 'poor' braking actions (wet ice remember) from my QRH.

So you're saying that if you have dispatched to your destination nothing would give you pause to consider whether your subsequent landing might or might not be legal...not even a TS/blizzard contaminating the runway...and if so you would be comfortable using raw data unfactored?

That's kinda scary.

Airbus and Boeing are certified to the same regulatory standards are they not?

However why don't you go back and read what I actually wrote rather than what you think I wrote.

[Gnadenburg]

fistfokker

Contaminated runway landings are not allowed.

How strange. Is that a limitation placed on J*?

The type of approach you have described in RPT Jet transport is a sure fire recipe for CFIT and should be actively discouraged.

Nobody would circle for real at 500' on one engine after an NPA to minima. It was a CASA licence renewal requirement. My point was licence renewal for you would seem to have softned.

The fact that so many relatively minor systems failures on Airbus aicraft may require Raw data, Hand Flown Approaches using manual thrust,

Not true at all. List a minor failure which will degrade to that extent.

Say a double failure of an inertial reference system? Luckily for Airbus they have three. Doesn't a 737 have only two?

You may think you are cleverer than the average Jet* pilot

Only in the fact that I never paid for my training

but

none of us would contemplate circling in the dark at 500ft

Just to remind you that as pointed out earlier this was a CASA Licence renewal requirment.

But complex profiles in the simulator help develop a solid elemental skill set. As alluded to ad nauseum, most Airbus accidents have been due a neglect fundamentals- including two aircraft flown into the water on GA.

[Gnadenburg]

Don
But you have used the contaminated table. Are you applying the 1.67 to those?

So, with your outfit, you have a single HYD failure with an increment that will inevitably come in under the 1.67; all of a sudden your required landing distance is less than prior to when the HYD system failed?

Lesson?

What was Air France's policy before non-endorsed Monday morning quarterbacks make profound statements as " the approach was never legal".
Even prior to dispatch the approach wasn't legal if I read some of you correctly!

[Chimbu chuckles]

Gnadenberg I don't understand your confusion...transport category is transport category. It matters not whether the label on the control column says Boeing or Airbus.

The A340 at Toronto was perfectly serviceable...up until it speared off the runway end and burst into flames.

This stuff is not Monday morning quarterbacking...it is airline pilot 101. How can I land on a runway in the conditions that exist at the time (who cares what the conditions were 10 hrs earlier) if I am unsure of the LDR + regulatory factors.

Whether you apply straight 1.67 to good, medium or poor braking distances or divide by .6 and multiply by 1.15 the answers won't be too far adrift from each other. In fact the Airbus method will be a little more restrictive.

[donpizmeov]

Gnads,

I used the 4.03, "Landing distance without autobrakes" runway condition covered with 12.7mm(1/2inch) water, corrected for tailwind and 4 operative reversers from that same page for the unfactored. And the landing with "autoland landing distance with autobrake", runway condition 12.7mm(1/2inch) water, corrected for tailwind and reversers from that same page for the factored. No extra multiples by me.

For a non-normal I would use the 4.03 distance multiplied by the "LDG CONF/APP SPD/LDG DIST FOLLOWING FAILURES" corrections as required. Depends what type of HYD failure you get mate. Could be upto a multiple of 2.4.

Anything else I can help with?

Don

[Gnadenburg]

RWY Length Toronto

2743

Actual LDG Distance:

dry=1264

wet= 1564

contaminated = 2016

Chimbu applies the 1.67 to the contaminated figure???????

( I will pour another glass of Amarone before bed ).

[Chimbu chuckles]

From Don's post.

Regulation defines the required landing distance as the actual landing distance divided by 0.6, assuming the surface is dry.

If the surface is wet, the required landing distance must be at least 115 % of that for a dry surface.

From Gnads post.

Dry runway unfactored

1264m

(1264/.6) x 1.15 = 2422m (Airbus method)

Toronto LDA 2743m

1264 x 1.82 = 2300m ( Australian method 1.67 +.15)

And the above figures are just for wet...not contaminated...at best the landing was so marginal as to be less than sensible but given it was contaminated rather than just wet I still believe the landing was probably illegal.

Edited because I remembered the wet figure rather than Gnads dry figure when I went to post with calc in hand.

[donpizmeov]

Gnads,

Above I have pasted a bit from the Airbus VOL 2 re how to change a actual landing distance to the required landing distance. JAR states you need a required landing distance, except in the case of non-normal.

Don

Chuck,

You would need to correct the dry distance as you have not the wet. For the wet distance you divide by .6 only. Remember these numbers are max landing weight. At a lesser weight (and I have no idea at what weight he was at) he would have been legal.

[Gnadenburg]

I see your logic and application.

However, pragmatically, every time it snows in Toronto enroute, you are now compelled to divert?