BA B777 Incident @ Heathrow (merged)
Join Date: Nov 1999
Location: AsiaPacific
Posts: 16
Likes: 0
Received 0 Likes
on
0 Posts
just a hunch from another angle, though not impossible. don't flame me.
aircraft correcting from low on glidepath to slot on FLCH SPD mode? correction left too late?
Capt handed control to Co-pilot on short finals. Why? Did Capt have to takeover and then hand over? Was co-pilot on training or a check? Did he goofed on FLCH SPD mode with throttle at idle. waiting for it to wake up to hold speed but did not, until a/c stall and too late to spool up manually.
just speculation at another angle.
aircraft correcting from low on glidepath to slot on FLCH SPD mode? correction left too late?
Capt handed control to Co-pilot on short finals. Why? Did Capt have to takeover and then hand over? Was co-pilot on training or a check? Did he goofed on FLCH SPD mode with throttle at idle. waiting for it to wake up to hold speed but did not, until a/c stall and too late to spool up manually.
just speculation at another angle.
Join Date: Dec 2006
Location: Florida and wherever my laptop is
Posts: 1,350
Likes: 0
Received 0 Likes
on
0 Posts
Software Failure?
PB365: "I wonder if this could point to a software failure? All software has bugs and one worrying statement I have heard is that sometimes a bug will take years to materialize."
Software code tends not to have too many bugs these days, and remember the code in each of the numerous computers on this and other B777s would have been exercised considerably and is being at this moment in the remaining B777s - all apparently satisfactorily. However, the software design - that is the logic and algorithms for dealing with exceptions where inputs from other computers or sensors are timed or scaled in an unexpected way - can have faults that lead to similarly unexpected failures (see http://www.alexisparkinn.com/nwpilot's_tranatlantic_flight.htm (day 2) http://www.freerepublic.com/focus/f-news/1791574/posts http://catless.ncl.ac.uk/Risks/3.44.html and probably many others). These exceptions are extremely difficult to test for as they may require a series of improbable events to happen in precise temporal sequence. Thus these faults can - as you say PB365 - take years to materialize.
This kind of 'fault' gives a particularly difficult problem to regulators. The chances of the event occurring is say 10 to minus 99 (that is it is less likely than an aircraft being hit by a meteorite on finals) -but in this case it has happened and made headlines so everyone knows it is possible. Do the regulators ground all the aircraft involved at huge impact to worldwide aviation; carry out modifications (that could well introduce similar logic faults); or, do they let the aircraft carry on flying while they carry out modifications or do nothing? Both of the latter options sets up the regulators to be vilified by the tabloid, and sometimes expert. press (not to mention experts on fora like this).
If the cause in this case is something more common then I would think that the AAIB would have already published an emergency alert to all affected operators especially considering the potential impact on transoceanic traffic with ETOPS.
Software code tends not to have too many bugs these days, and remember the code in each of the numerous computers on this and other B777s would have been exercised considerably and is being at this moment in the remaining B777s - all apparently satisfactorily. However, the software design - that is the logic and algorithms for dealing with exceptions where inputs from other computers or sensors are timed or scaled in an unexpected way - can have faults that lead to similarly unexpected failures (see http://www.alexisparkinn.com/nwpilot's_tranatlantic_flight.htm (day 2) http://www.freerepublic.com/focus/f-news/1791574/posts http://catless.ncl.ac.uk/Risks/3.44.html and probably many others). These exceptions are extremely difficult to test for as they may require a series of improbable events to happen in precise temporal sequence. Thus these faults can - as you say PB365 - take years to materialize.
This kind of 'fault' gives a particularly difficult problem to regulators. The chances of the event occurring is say 10 to minus 99 (that is it is less likely than an aircraft being hit by a meteorite on finals) -but in this case it has happened and made headlines so everyone knows it is possible. Do the regulators ground all the aircraft involved at huge impact to worldwide aviation; carry out modifications (that could well introduce similar logic faults); or, do they let the aircraft carry on flying while they carry out modifications or do nothing? Both of the latter options sets up the regulators to be vilified by the tabloid, and sometimes expert. press (not to mention experts on fora like this).
If the cause in this case is something more common then I would think that the AAIB would have already published an emergency alert to all affected operators especially considering the potential impact on transoceanic traffic with ETOPS.
Join Date: Aug 2004
Location: Unsure
Posts: 2
Likes: 0
Received 0 Likes
on
0 Posts
you don't need an intentional RF emitter such as a mobile phone, to cause interference, either in-band or out-of-band
I would imagine the emissions would have to be at a pretty high level to cause any kind of non-recoverable glitch (latching).
Join Date: Dec 2000
Location: on the golf course (Covid permitting)
Posts: 2,131
Likes: 0
Received 0 Likes
on
0 Posts
Capt handed control to Co-pilot on short finals. Why? Did Capt have to takeover and then hand over? Was co-pilot on training or a check?
It therefore would be totally in line with that policy for the SFO to take control from the Captain at about 1000 ft.
All mode selections would have been monitored and verbalised, so FLCH remaining engaged is highly unlikely.
Join Date: Aug 2004
Location: London
Posts: 12
Likes: 0
Received 0 Likes
on
0 Posts
787Focal wrote:You could have a laptop running and a cell phone in every seat and you still would not affect anything on an airplane.
Join Date: Apr 2002
Location: UK
Posts: 386
Likes: 0
Received 0 Likes
on
0 Posts
@ 7times7
Ba procedures entail a monitored approach ai the p2 flies the STAR and approach for the p1 for the sector.
In this case it would have been the FO's sector and Cpt flying the approach for the FO's landing.
Typically control is handed over at a 1000' (Auto Call out by the RadAlt) by the words 'I have control' (can be done at different stages of the approach but this tends to be the place to do the handover).
No-one flies it at FLCH SPD at that stage on the approach
(2 reasons: if they were unstable they would be flying it manually to correct the path, so AFDS modes completely irrelevant. And: LHR is not a place to come in rushed with all the speed/gate control as appropriate for a CDA)
Enough speculation, just wait for the AAIB report when it comes.
I think you will find there is a very good explanation of what happened.
Why else would the CEO in front of a media frenzy tell the press the crew were heroes...
No company will shoot themselves in the foot.
Ba procedures entail a monitored approach ai the p2 flies the STAR and approach for the p1 for the sector.
In this case it would have been the FO's sector and Cpt flying the approach for the FO's landing.
Typically control is handed over at a 1000' (Auto Call out by the RadAlt) by the words 'I have control' (can be done at different stages of the approach but this tends to be the place to do the handover).
No-one flies it at FLCH SPD at that stage on the approach
(2 reasons: if they were unstable they would be flying it manually to correct the path, so AFDS modes completely irrelevant. And: LHR is not a place to come in rushed with all the speed/gate control as appropriate for a CDA)
Enough speculation, just wait for the AAIB report when it comes.
I think you will find there is a very good explanation of what happened.
Why else would the CEO in front of a media frenzy tell the press the crew were heroes...
No company will shoot themselves in the foot.
Join Date: Dec 1999
Location: UK
Posts: 2,584
Likes: 0
Received 0 Likes
on
0 Posts
Far from yesterday's statement from the Capitain that crew training took over automatically - Coward says there are absolutely no drills for handling a situation such as the one they faced. Whereas there are, of course, procedures for losing power at higher altitudes - there's nothing in the manual to prepare a pilot for what he should do when the power fails at 600 feet
How could there be drills for total power loss at 600ft - what a ludicrous concept!
The training that took over was to fly the aeroplane so as to survive the landing if at all possible, what the hell else could they do? All they did was to fly the aeroplane, which is precisely what they are trained to do...
The implications of this being a technical failure do not bear thinking about. If this is confirmed we are going to see an awful lot of big twins (read, half of them - the Boeing half alone if we are lucky) lying idle on the ground, as well as hundreds of thousands of pax unable to travel until the matter is sorted. The implications for global aviation in this scenario could make Sept 11th look like a minor temporary glitch...
We rely enormously on ETOPS, any discrediting of the equipment or the concept would change the face of long-range aviation totally.
Join Date: Jun 2007
Location: Closer than you think
Posts: 90
Likes: 0
Received 0 Likes
on
0 Posts
You could have a laptop running and a cell phone in every seat and you still would not affect anything on an airplane.
Really? Then how do you explain this?
Join Date: May 2005
Location: uk
Posts: 573
Likes: 0
Received 0 Likes
on
0 Posts
Forget about approach/flight idle.. The engines are not going to be at idle on a 3 degree glidepath with landing flaps and gear hanging out (The captain said it was a normal approach until 2 miles out). You need thrust to maintain a 3 degree glidepath.
Is this pure ignorance or what? I mean in most major airport we struggle to get the thrust back up by 500ft due to 160Kts to DME 4 so then yes iddle is very normal indeed.
Join Date: Dec 2002
Location: UK
Posts: 53
Likes: 0
Received 0 Likes
on
0 Posts
RESA distances - close call
As somebody involved in airport development one thing strikes me, I am not sure what the current ICAO recommendations are on RESA lengths without looking them up, nor how compliant the ones are at Heathow are by the latest standards, but they on this occasion by the narrowest of margins they proved to be enough.
I am sure at certain other airports a failure at the same point in late finals would have been horrendous, it’s certainly an area I will pay a lot more attention to.
It also was incredibly refreshing to see Willie Walsh leading from the front and endorsing the pilots and Crew’s actions without hesitation, I am aware that his background enables him to have better insight to this incident than most senior executives, but made a nice change from the distancing tactics than some employers have shown in previous incidents.
Lets only hope that the investigators at the AAIB are able to identify the causes and make recommendations, thankfully without for once any loss of life or major injuries.
I am sure at certain other airports a failure at the same point in late finals would have been horrendous, it’s certainly an area I will pay a lot more attention to.
It also was incredibly refreshing to see Willie Walsh leading from the front and endorsing the pilots and Crew’s actions without hesitation, I am aware that his background enables him to have better insight to this incident than most senior executives, but made a nice change from the distancing tactics than some employers have shown in previous incidents.
Lets only hope that the investigators at the AAIB are able to identify the causes and make recommendations, thankfully without for once any loss of life or major injuries.
Join Date: Sep 2006
Location: Scotland
Posts: 12
Likes: 0
Received 0 Likes
on
0 Posts
I believe the advice given to WW2 pilots by the original Pilot Officer Prune was "When a prang seems inevitable, endeavour to strike the softest, cheapest object in the viscinity as slowly and gently as possible...." A job well done by all the crew involved, not forgetting the airfield staff too.
Join Date: Dec 2006
Location: Florida and wherever my laptop is
Posts: 1,350
Likes: 0
Received 0 Likes
on
0 Posts
End Arounds
ILS27L "A lesson: all runways should be like 27Left from now on. This incident could happen again. Same incident on 27 right at EGLL and the 777 would have found the VS Car Park. Slightly harder than the wet grass. RESA needed.
Let's move these car parks."
I second that one. I have seen recent research designs for 'perfect airports' out of universities here in the U.S. (from non-ATC trained engineering professors) where to maintain acceptance rate without runway crossings, the idea of 'end-around' taxiways through overshoot and undershoot areas is recommended and pressed hard. Indeed ATL now has an 'end-around' on 08R but currently only on the undershoot of what is normally a departure runway. The Air France overrun at Toronto and the South West overrun at Midway are other cases that show that undershoot and overrun areas of active runways are not places to be without crossing clearance.
However, the airport operators are driven by the one or two runway operations an hour increase in capacity rather than the potential for collisions. Not to mention all that car parking space!
Let's move these car parks."
I second that one. I have seen recent research designs for 'perfect airports' out of universities here in the U.S. (from non-ATC trained engineering professors) where to maintain acceptance rate without runway crossings, the idea of 'end-around' taxiways through overshoot and undershoot areas is recommended and pressed hard. Indeed ATL now has an 'end-around' on 08R but currently only on the undershoot of what is normally a departure runway. The Air France overrun at Toronto and the South West overrun at Midway are other cases that show that undershoot and overrun areas of active runways are not places to be without crossing clearance.
However, the airport operators are driven by the one or two runway operations an hour increase in capacity rather than the potential for collisions. Not to mention all that car parking space!
Join Date: May 2005
Location: uk
Posts: 573
Likes: 0
Received 0 Likes
on
0 Posts
You need thrust to maintain a 3 degree glidepath.
If I asked you : Can you climb without thrust? You would say off course not! thinking I was mad. But the correct answer is: yes, sacrificing speed.
This just comes to show your lack of experience/knowlegde.
I think is time pprune limits it's access to proffesionals only, this people have no idea what they are talking about.
Join Date: May 2005
Location: USA
Posts: 65
Likes: 0
Received 0 Likes
on
0 Posts
I have extensive flight test experience. The equipment we bring on board to monitor the aircraft systems, performance and navigation are off the shelf computers and electronics that are hand built.
I can't even count the amount of times I have used a cell phone on the flight deck of an aircraft, many times during approach to tell the wife what time I would be home for dinner.
How many of you pilots have used hand held GPS on the flight deck? (I know nobody will answer that)
As one poster pointed out, all the sensative electronics are tested and shielded for EMI.
The reall reason they don't want you using and electrical devices during takeoff and approach is because they don't want them flying into people if a crash happens. How do you think a cell phone would feel at 100 mph?
(I had a can of coke fly from the back of a 727 all the way to almost the front about 3 ft in the air when the pilot hit the brakes when we landed. There was no interior in the plane except a row for me to sit in to watch the wings and make sure nothing flew off during stalls)
fyi - Isn't there an airline in the EU that is installing a system that will allow people to make and receive cell calls in flight?
I can't even count the amount of times I have used a cell phone on the flight deck of an aircraft, many times during approach to tell the wife what time I would be home for dinner.
How many of you pilots have used hand held GPS on the flight deck? (I know nobody will answer that)
As one poster pointed out, all the sensative electronics are tested and shielded for EMI.
The reall reason they don't want you using and electrical devices during takeoff and approach is because they don't want them flying into people if a crash happens. How do you think a cell phone would feel at 100 mph?
(I had a can of coke fly from the back of a 727 all the way to almost the front about 3 ft in the air when the pilot hit the brakes when we landed. There was no interior in the plane except a row for me to sit in to watch the wings and make sure nothing flew off during stalls)
fyi - Isn't there an airline in the EU that is installing a system that will allow people to make and receive cell calls in flight?
Join Date: Dec 1999
Location: UK
Posts: 2,584
Likes: 0
Received 0 Likes
on
0 Posts
I think is time pprune limits it;s access to proffesionals only, this people have mo idea what they are talking about.
Join Date: May 2005
Location: uk
Posts: 573
Likes: 0
Received 0 Likes
on
0 Posts
Agraricus bisporus , (mushroom, for non latin speakers...)
Well you may have noticed I corrected the errors on my spelling before you actually posted a time wasting post.
By the way English is not my mother tongue so I do have a excuse...
You wouldn't happen to be the British pilot overflying Egypt 2 weeks ago saying on the radio:
Cairo , XXXX123 , we have tried to call Hurghada on the box , no reply, please give them a call on the landline fo us.
He never realized that it was his english that was causing the problem, what about:
Cairo , XXXX1123, no contact with Hurghada on frequency 123.455 , please call Hurghada by telephone for us.
I don't think that was up to ICAO level 4....
Quote:
I think is time pprune limits it;s access to proffesionals only, this people have mo idea what they are talking about.
Eagle, would you extend that ban to "proffesional" writers too?
I think is time pprune limits it;s access to proffesionals only, this people have mo idea what they are talking about.
Eagle, would you extend that ban to "proffesional" writers too?
Well you may have noticed I corrected the errors on my spelling before you actually posted a time wasting post.
By the way English is not my mother tongue so I do have a excuse...
You wouldn't happen to be the British pilot overflying Egypt 2 weeks ago saying on the radio:
Cairo , XXXX123 , we have tried to call Hurghada on the box , no reply, please give them a call on the landline fo us.
He never realized that it was his english that was causing the problem, what about:
Cairo , XXXX1123, no contact with Hurghada on frequency 123.455 , please call Hurghada by telephone for us.
I don't think that was up to ICAO level 4....