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LH A320 Rough Landing @ Hamburg

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LH A320 Rough Landing @ Hamburg

Old 5th Mar 2008, 11:40
  #281 (permalink)  
 
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Originally Posted by Chris Scott View Post
PS: Wader2, Remember, this event is defined as an "incident", not an "accident"!
Thanks Chris, I stand corrected. I made the accident/incident assumption on the grounds that actual damage had occurred as opposed to an incident where damage might have occurred.

In my area it would still be an accident.
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Old 5th Mar 2008, 12:13
  #282 (permalink)  
 
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Originally Posted by Wader2

In my area it would still be an accident.
I don't know what "your area" is, but ICAO has quite specific definitions. Particularly, an accident is an occurrence where an aircraft sustains damage adversely affecting performance and requiring major repair or replacement of a component. (There are other conditions that make an occurrence an accident, but this one is the closest for this case.)

It might be argued that this was the case here, although I think the pilots still had full control authority. The wingtip fences' functions are reducing wake vortex ("induced drag") and thereby saving fuel.

However, ICAO Annex 13 makes the specific restriction:

[...] except for engine failure or damage, when the damage is
limited to the engine, its cowlings or accessories; or for
damage limited to
propellers, wing tips, antennas, tires,
brakes, fairings, small dents or puncture holes in the
aircraft skin
So this is without doubt an incident, and not an accident according to internationally agreed definitions.

Bernd
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Old 5th Mar 2008, 12:14
  #283 (permalink)  
 
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Originally Posted by Dream Land View Post
Did you watch the same video as I did, that approach was incredibly bad, tried to save it and screwed that up too.
Thanks DL, the operative word in my post was appeared. I saw the video clip just once on the TV News and thus my assessment was really a real-time snapshot. I bow to the slow time analysts. (not being rude I assure you).
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Old 5th Mar 2008, 12:35
  #284 (permalink)  
 
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Originally Posted by bsieker View Post
an accident is an occurrence where an aircraft sustains damage adversely affecting performance and requiring major repair or replacement of a component.

. . .

It might be argued that this was the case here, although I think the pilots still had full control authority.
Bernd, military.

I am glad that replacement of the end of the wing was a minor repair not requiring extensive checking of the mainplane structure. Fortunately it is unlikely I will be flying LH in the near future.

If it's an incident fine, all in a word.
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Old 5th Mar 2008, 12:55
  #285 (permalink)  
 
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FMC/FMGC wind readouts

drkraft


I'm surprised no one has mentioned it yet but your best source of realtime information on FMC equipped aircraft during landing is Prog page 2 (Boeing types).
I may be misunderstanding you but I do know that too many pilots refer to the FMC/FMGS wind readouts on approach with regard to their company limits but any such limits are referenced to w/v on the surface (or pehaps more accuaretly 15 metres above the surface).

I always have one of the FMC's on that page during landing.It keeps me legal and keeps me from getting surprised
Or are you saying that you literally have you colleague looking at the FMC page at 50' agl when they should perhaps be closely monitoring other parameters

There is no doubt that the w/v from the FMC has got some value but given the huge variations that can occur between reported surface wind and winds aloft, I would suggest that it's real value is to give a clue to expected shears as you approach touchdown.
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Old 5th Mar 2008, 13:02
  #286 (permalink)  
 
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OKhasla

QUOTE]The skipper was : YOURS truly. The F/O... well he has moved on to become a great skipper. The F/E; he probably learnt a lot that day and too took up flying as f/o and is now a junior skipper![[/QUOTE]

Great repect to you for such an honest and very interesting posting.
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Old 5th Mar 2008, 14:43
  #287 (permalink)  
 
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Starbear,
It's like any other tool you have in your toolkit. I said I use it as a reference, not a primary instrument. It's just another reminder that you might want to start thinking about plan B in case plan A isn't working out.
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Old 5th Mar 2008, 14:45
  #288 (permalink)  
 
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More Brainless Journalism:

Inside Edition, a syndicated US newsmagizine program heavy on celebrities,
doing a predictable "scared pax" story, led off with "150 mile-per-hour crosswinds". This broadcast was Tues, yesterday. Do these people ever check anything?
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Old 5th Mar 2008, 15:02
  #289 (permalink)  
 
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GMDS, you said: "there is definitely a small roll input on the AB when decrabbing, which is not on a B.)"

It doesn't matter if it's a Boeing or an Airbus, ALL swept wing jet aircraft will have some additional roll moment induced upon "decrabbing" (input of downwind rudder). This is due to a reduction of "sweep" on the upwind wing in relation to the relative wind, thus an increase in lift on that upwind wing (as it 'swings' into the wind w/ a lesser angle), and the opposite affect upon the downwind wing- "more sweep" reduces lift on that one. Low, upwind wing required, at that point, to maintain runway track and actually landing on runway.
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Old 5th Mar 2008, 15:19
  #290 (permalink)  
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KC135777;
ALL swept wing jet aircraft will have some additional roll moment induced upon "decrabbing"
I think the point of the post was, Airbus WILL correct that rolling moment due to roll-control laws (as discussed extensively here) and Boeing will not correct the roll. I think we all agree that the aircraft will have a roll moment when de-crabbing, especially a swept-wing design.

My original point about some pilots believing that AB would "put the wing down" remains...some pilots believe that the airplane will de-crab and put sufficient wing down to continue tracking straight. Such an understanding is not correct.

The AB autoland will do this up to a point, perhaps because it has track-guidance, but it will land slightly crabbed, notwithstanding.

I think the post by Bernd, providing the Airbus Bulleting #54/2 (post #243) is worth reading closely.
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Old 5th Mar 2008, 15:19
  #291 (permalink)  
 
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Very few if any FMS provide ‘real time wind’. Most are heavily damped using averaging laws. If you do not know exactly how your FMS calculates wind then it should be treated with caution especially for ‘precision type’ decisions.

Just because the wind etc, is within legal limits (rules vs FMS or tower report), does not mean that the attempt to land is the safest option; that requires judgement and skilled thinking.
“Its not the pilot’s hands that get them into trouble, its their heads” James Reason.

The recommendations in the report linked in post #136 indicate that a realistic crosswind limit (applied by the crew/operator) should always include the gust.

‘Safety aspects of aircraft operations in crosswind’
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Old 5th Mar 2008, 15:23
  #292 (permalink)  
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If you look at the damages observed in:

http://www.hamburg-airport-friends-f...d=2607#pid2607

the pictures show that there is a little more to look at, and work on, that wing and the plane as well. Just take account of the scratches on the underwing-not the tip winglet. My experience as an old certification crew member yields something about the "g"-s of the tip ground contact; the elongation of the deformation was just elastic or... is it inside limits? I remember changing two years official letters with the designers before approving to service a TU154 which touched with the wingtip the snow in Berlin during a low vis app GA back in '80-s.
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Old 5th Mar 2008, 16:31
  #293 (permalink)  
 
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Hideous flying. Check out post #51. Wingtip's on the ground and hardly any control input to stop the roll.
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Old 5th Mar 2008, 16:43
  #294 (permalink)  
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So what??????????????
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Old 5th Mar 2008, 16:58
  #295 (permalink)  
 
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So what???

Good luck in your longevity planning.
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Old 5th Mar 2008, 17:05
  #296 (permalink)  
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I was saying earlier (NET LOST MY MESSAGE) that according with the pictures in:

http://www.hamburg-airport-friends-f...d=2607#pid2607

it is important the "g" on ground contact. Back in '80-s as RCAR eng., I was changing two years official messages with the designers before clearing to service a TU154, after a wingtip contact with snow in a low viss. app. GA at Berlin SFX.
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Old 5th Mar 2008, 17:33
  #297 (permalink)  
 
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If you watch the vid, he turned over rather suddenly- how fast is your reaction time to something you don't expect?
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Old 5th Mar 2008, 17:37
  #298 (permalink)  
 
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Maximum certificated crosswind component (GUST)

Quote from PEI_3721:
The recommendations in the report linked in post #136 indicate that a realistic crosswind limit (applied by the crew/operator) should always include the gust.
[Unquote]

Haven't read the report (46 pages), but the A320 crosswind limits I worked to did include a maximum GUST (component) of 38kts, as has appeared somewhere else on this thread.

What I cannot remember are the limits on a wet runway, which are normally lower.


On a slightly different note, here is one for the genuine A320 pilots who have suggested that the aeroplane is a particular handful in gusty crosswinds, presumably because of its FBW controls:

How come the FAA and CAA - not to mention the other authorities applicable in 1988 - granted type-certification with a maximum crosswind-component of 38 knots in gust?

Do you think they didn't try it out? Or could it be that some of you guys have not been briefed and trained properly?
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Old 5th Mar 2008, 17:49
  #299 (permalink)  
 
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fish Decrabbing

I think we all agree that the aircraft will have a roll moment when de-crabbing
Quite difficult with so many ex-RAF types around, I imagine
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Old 5th Mar 2008, 18:01
  #300 (permalink)  
 
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" seventhree:

Pitch goes gradually to direct, roll not. And that makes it tricky...
Rudder is always direct.
Pitch direct is blended in gradually and reached around 50ft and even a light nose down momentum is induced to you make you pull the stick. Stabilizer position is also a key factor for pitch control (if it's bad you can hit the mechanical stop of the stick)"

WRONG

Flare mode memorizes the pitch and gradually introduces a nose down trend but the sidestick still commands load factor or angle of attack (mode dependant) Direct control of the elevators does not occur until after touchdown.
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