Go Back  PPRuNe Forums > Flight Deck Forums > Accidents and Close Calls
Reload this Page >

United at Zurich...what happened here..?

Accidents and Close Calls Discussion on accidents, close calls, and other unplanned aviation events, so we can learn from them, and be better pilots ourselves.

United at Zurich...what happened here..?

Old 3rd Jun 2024, 02:41
  #21 (permalink)  
 
Join Date: Mar 2015
Location: Virginia, USA
Posts: 498
Likes: 0
Received 34 Likes on 24 Posts
Originally Posted by BugBear
"and if you don't ''hold'' the Nose Gear it will slam the Nose Gear into the runway."

​​​​​
Never experienced such an NG slam. Can you expand on that?
Thereís a thread in this forum regarding the July 2023 accident for UA702 (N641UA, B767-300) where the new FO accomplished a NG slam hat trick.
BFSGrad is offline  
Old 3rd Jun 2024, 09:45
  #22 (permalink)  
 
Join Date: Aug 2007
Location: The sky
Posts: 343
Received 7 Likes on 2 Posts
Fullwings,

The spoilers donít deploy on the first landing, what youíre seeing is the horizontal stabiliser appearing above the wing as the aircraft derotates.

Looking at the lack of deceleration and no spoiler deployment it looks very much like a thrust lever (significantly) not at idle landing. Think steep approach, windy day, shortish runway, low experience, rabbit in the headlights.

LD

Locked door is offline  
Old 3rd Jun 2024, 10:12
  #23 (permalink)  
Too mean to buy a long personal title
 
Join Date: Aug 2002
Location: UK
Posts: 1,974
Received 10 Likes on 5 Posts
Originally Posted by Locked door
The spoilers donít deploy on the first landing, what youíre seeing is the horizontal stabiliser appearing above the wing as the aircraft derotates.
Isn't it the spoilers that pop up briefly at 0:34? More visible on the left wing than the right, but the outboard edge of what appears and then disappears is just above the outboard flap track fairing. But the angle makes it difficult to know how long they're actually up for.
Code:
https://www.youtube.com/watch?v=3_jsQ_EwXZw&t=33s
Globaliser is offline  
Old 3rd Jun 2024, 10:20
  #24 (permalink)  
 
Join Date: Aug 2007
Location: The sky
Posts: 343
Received 7 Likes on 2 Posts
Pretty sure thatís an aileron.
Locked door is offline  
Old 3rd Jun 2024, 10:56
  #25 (permalink)  
 
Join Date: Jun 2002
Location: Southern Europe
Posts: 324
Received 2 Likes on 1 Post
Originally Posted by BugBear
"and if you don't ''hold'' the Nose Gear it will slam the Nose Gear into the runway."

​​​​​
Never experienced such an NG slam. Can you expand on that?
Normally one touches down with an attitude of, say, 3 or 4ļ.
The Autobrakes, if armed, will act almost immediately, and will cause a de-rotation of the aircraft, which one learns to counteract, because if you don't counteract that de-rotation movement, the Nose Gear will land firmly on the runway.
Brought this detail up because if one is used to land with Autobrakes armed, and used to counteract the normal de-rotation that the Autobrakes cause, if one day, for whatever reason the Autobrakes are not functional, it is necessary to keep that in mind, because if one does the normal counteract to compensate for the braking, and the braking is not happening on that day, then one can eventually get in an High Nose attitude after the touchdown.

Wondering if the spoilers didn't deploy because they had already decided to go around?
Agree with that. Could be that because of the initial bounce they decided to go-around.
Had a look at the video a few times attempting to see (hear) if it be possible to hear the moment when, it looks to me, the GEs spooled-up for the go-around, but could not establish that moment. Either it is not possible, or my internet is not good enough for that.

Like Locked Door mentions, it doesn't look like that there was ever any decelaration after the initial touchdown.

Lets assume that, due to the initial bounce, they decided at that moment to go-around. When the engines response gets to the ''full steam ahead'' point, or close to that, the problem that then happens is a very strong Pitch-up tendency which one has to counteract to avoid a tailstrike. It might explain the non-normal attitudes that happened until they finally got in a steady go-around.

A go-around after touchdown is far more demanding, trickier, than a go-around at minimuns.

Last edited by zerograv; 3rd Jun 2024 at 13:27. Reason: grammar
zerograv is offline  
Old 3rd Jun 2024, 11:33
  #26 (permalink)  
 
Join Date: Dec 2003
Location: Tring, UK
Posts: 1,893
Received 38 Likes on 21 Posts
The spoilers donít deploy on the first landing, what youíre seeing is the horizontal stabiliser appearing above the wing as the aircraft derotates.
There is what *could* be a very short-lived deployment when the aircraft finally settles if you look outboard. The pitch is high enough by then that Iím not sure if you could see the rest of the spoilers from the camera viewpoint and as said earlier it might be an aileron but you donít see it before this point.

Lets assume that, due to the initial bounce, they decided at that moment to go-around. When the engines response gets to the ''full steam ahead'' point, or close to that, the problem that then happens is a very strong Pitch-up tendency which one has to counteract to avoid a tailstrike. It might explain the non-normal attitudes that happened until they finally got in a steady go-around.
Itís a good theory, but on the recording the TD occurs at 0:23 and the first signs of N1 increasing are at 0:35 just before the nose lowers. Thatís 12 seconds which tells me that the GA decision was actioned no earlier than 8-9s after TD, so after much of the porpoising.

Given that it appears they had no ground spoilers, no reverse and little to no braking (as they got back into the air quite quickly after the thrust came up), it was a good call to throw it away.
FullWings is offline  
Old 3rd Jun 2024, 14:13
  #27 (permalink)  
 
Join Date: Jan 2005
Location: Europe
Posts: 264
Received 6 Likes on 3 Posts
Maybe the go-around was initiated, but go-around thrust was initially not set (autothrottle disengaged), like Emirates 521? Would be interesting to see a report, but I doubt the analysis of this occurrence will go beyond internal review by the airline.
xetroV is offline  
Old 4th Jun 2024, 16:09
  #28 (permalink)  
 
Join Date: Jan 2022
Location: Miami
Posts: 103
Likes: 0
Received 4 Likes on 2 Posts
to add to this, the go-around was after a ??? 7+ hour flight, conducted on an otherwise shortish runway, and likely not "expected"

I think they did a good job, considering everything.

321XLR is offline  
The following 3 users liked this post by 321XLR:
Old 5th Jun 2024, 05:14
  #29 (permalink)  
 
Join Date: Jul 2007
Location: Auckland, NZ
Age: 79
Posts: 728
Likes: 0
Received 3 Likes on 2 Posts
Originally Posted by Locked door
Fullwings,

The spoilers donít deploy on the first landing, what youíre seeing is the horizontal stabiliser appearing above the wing as the aircraft derotates.
SNIP
LD
I see it like Fullwings: the thing, whatever it is, appears above the port wing too far outboard to be the horizontal stabiliser. A similar thing appears above the starboard wing, though less prominently: that one really needs looking at frame-by-frame to be sure.
FlightlessParrot is offline  
Old 5th Jun 2024, 05:42
  #30 (permalink)  
 
Join Date: Jul 2005
Location: Honolulu
Posts: 208
Received 7 Likes on 4 Posts
They did a "good job" in the fact that they did not bend metal or hurt anyone.
But really it seems like the go-around should have been initialized earlier. Almost got a tail strike and seemingly poor rudder and pitch control.
Junkflyer is offline  
The following users liked this post:
Old 5th Jun 2024, 14:27
  #31 (permalink)  
 
Join Date: Jul 2007
Location: Germany
Posts: 1,035
Likes: 0
Received 8 Likes on 3 Posts
A friend on this fleet told me Zurich was a regular initial operating experience route. United has been taking new hires with relatively low experience (eg regionaljet) directly onto the 767. This is at least the second landing mishap in the recent past for them. I can only remember taking off on the cross runway at Zurich. I can imagine things were a little tense for a moment until they got it sorted.
lederhosen is offline  
Old 5th Jun 2024, 20:17
  #32 (permalink)  
 
Join Date: Dec 2002
Location: Where the Quaboag River flows, USA
Age: 71
Posts: 3,454
Received 25 Likes on 10 Posts
I suppose there’s something to be said for bounce drills for new FOs without heavy jet time.
galaxy flyer is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.