Possible Tailstrike UA 744

[KrishnaM]

Hi guys just looking out over the lighthouse from CBD looks like a comercial doing circles and some dark contrails behind...

any ideas???

[Donald H]

United 870 dumping fuel after tailstrike.

[Nigel C]

Just about to join final for 34L. Nil services required.

[Andrew P]

must have been the UA 747 that went over Pymble at about 3.00pm, following a non-normal departure route

[Tony G]

I happen to get a couple of shots of the tail strike. Cannot actually see the contact due to my short ladder, however the attitude of the take off says it all. I had the scanner on and I dont think the United aircrew realised they made contact. It was the Etihad pilot on taxi out to the bay that reported it to ATC. Forgive the quality of the shots, it is me we are talking about:p. The ground staff reported metal shavings on the runway and had to be swept up before 34L and 25 were available.

http://i486.photobucket.com/albums/rr222/DAplane/TS3.jpg

http://i486.photobucket.com/albums/rr222/DAplane/TS2.jpg

http://i486.photobucket.com/albums/rr222/DAplane/TS1.jpg

[Tony G]

Rego was N128UA.

[Nigel C]

... however the attitude of the take off says it all.

Not really...United and the LA/Jo'burg bound QF birds often get the tail to within a few feet of the runway.

With no dust cloud visible in the shots one could argue that that's how they always look on departure. It doesn't help that the United aircraft has past the crest of the runway and has just begun the downhill run.

[Tony G]

Totally agree Nigel (should be Robocop :rolleyes:). I will not use these shots as evidence, however these are shots I have taken of an aircraft reported to have had a tail strike by another airline that was taxi. I thought I'd like to share them. I did say a couple in the original post and added three photos ( I am surprised you did not pick me up on that one:p). To me on the last shot the tail does look very close, and yes as mentioned in the previous post cannot see due to my line of sight.

[Nigel C]

Robocop? Nah...I've just seen one or two (thousand perhaps?) departures from close up over the years and still appreciate just how close they come without actually hitting.

[Sarah C]

I was wondering the same thing - I could see the aircraft doing circles and I couldn't tell what it was. Thanks for the info.

[Tony G]

Robocop? Nah...I've just seen one or two (thousand perhaps?) departures from close up over the years and still appreciate just how close they come without actually hitting.

Well you know better than me. I have been spotting for many years now but probably do not get as close as you do. And yes they do get very close, seen a few 777 come close as well. Can argue that the tail of the aircraft has dug itself into the ground from those photos:p, sorry could not help myself.

[Sarah C]

Amazing - change the colour of the tail and it is a front page news story. I have only seen one mention of it so far:

http://www.straitstimes.com/BreakingNews/World/Story/STIStory_523841.html

SYDNEY - A UNITED Airlines flight bound for San Francisco was forced to turn back to Sydney within two hours of departure on Friday after the jumbo jet reportedly clipped its tail during takeoff.

A United spokeswoman confirmed that the Boeing B747-400 had returned to Sydney for maintenance checks but would not confirm the media reports about the tail incident.

'I can confirm that UA870 departed from Sydney at 2.45 pm for San Francisco today and has returned to Sydney Airport for maintenance checks,' she told AFP. 'It landed without incident at 4.20 pm.'

[Grahame Hutchison]

Looks like it got underway again ...

N128UA UA0870 07/05/2010 14:58 United Airlines B747-422 Sydney-San Francisco-Chicago
N128UA UA0870 07/05/2010 16:08 United Airlines B747-422 Sydney-San Francisco-Chicago

[Grahame Hutchison]

And here are the details from ACARS ....


Operating the UA0840 service from Melbourne ...

ACARS mode: S Aircraft reg: .N128UA
Message label: H1 Block id: 0 Msg. no: F58A
Flight id: UA0840
Message content:-
#M1BPOSS34061E150498,TAMMI,021332,87,BOOGI,021540, DUDOK,P5,1655,315,,/TS021332,070510A27A
-------------------------------------[07/05/2010 12:13]
ACARS mode: S Aircraft reg: .N128UA
Message label: H1 Block id: 1 Msg. no: F59A
Flight id: UA0840
Message content:-
#M1BPOSS34021E151003,BOOGI,021524,60,DUDOK,021628, NASHO,P6,35013,313,,/TS021526,070510F23C
-------------------------------------[07/05/2010 12:15]
ACARS mode: S Aircraft reg: .N128UA
Message label: H1 Block id: 2 Msg. no: F60A
Flight id: UA0840
Message content:-
#M1BPOSS34050E151045,DUDOK,021624,53,NASHO,021756, SOSIJ,P8,00411,312,,/TS021627,0705106ABE
-------------------------------------[07/05/2010 12:16]

Operating the UA0870 service to San Francisco ...

ACARS mode: S Aircraft reg: .N128UA
Message label: 5Z Block id: 6 Msg. no: M33A
Flight id: UA0870
Message content:-
/C4 SYDSYD
DUMP COMENCED AT 0510Z
DUMP TIME 50 MINS.
HOLDING ON SY 060 RAD
AT 40 DME LEFT CIRCUIT
-------------------------------------[07/05/2010 15:38]
ACARS mode: S Aircraft reg: .N128UA
Message label: 5Z Block id: 1 Msg. no: M36A
Flight id: UA0870
Message content:-
/71 SYDSYD 0\FLOOR PANELS NEAR SEATS 59AB LOOSE
-------------------------------------[07/05/2010 15:51]
ACARS mode: S Aircraft reg: .N128UA
Message label: 5Z Block id: 6 Msg. no: M38A
Flight id: UA0870
Message content:-
/B6 SYDSYD SYD R34L F30
-------------------------------------[07/05/2010 16:09]

[Nigel C]

Looks like it got underway again ...

N128UA UA0870 07/05/2010 14:58 United Airlines B747-422 Sydney-San Francisco-Chicago
N128UA UA0870 07/05/2010 16:08 United Airlines B747-422 Sydney-San Francisco-Chicago

Nope, it returned to Sydney at 1620 after dumping fuel. Initial departure was about 1500. Your ACARS reports in the post below this one quoted confirm the dump time.

[Nigel C]

Well you know better than me. I have been spotting for many years now but probably do not get as close as you do. And yes they do get very close, seen a few 777 come close as well. Can argue that the tail of the aircraft has dug itself into the ground from those photos:p, sorry could not help myself.

The worst tail scrapes I've seen in previous years were off B777-300's. Singapore had one that left quite a deep and very long gouge not long after they started using them into Sydney. Thai were another culprit, again with the B777-300.
Thankfully with a bit more practice since then they don't seem to hit them anymore...

You could also argue that this bird has no undercarricage apart from the nosewheel too. No wonder the tail hit....;)

[Grahame Hutchison]

Hi Nigel, the way I have programmed my ACARS setup is to report the first receipt of a unique Registration / Flight number combination for the day, which could be up to 30 minutes out of YSSY. This works perfectly for commercial operations where every service is a different flight number normally. To pickup all corporate movements where the same flight number is generally used all the time, there is a one hour reset of this rule in place. This is also handy for the Emirates EK418/419 services as the turnaround in Sydney is over the hour reset mark, and ACARS will report the service in and out of Sydney with the same Registration / Flight number combination.

In the original post above I assumed that the second pickup was the delayed departure (although the times looked a little close), but from reports in another thread (Monty) it actually stayed overnight.

[Grahame Hutchison]

If fact that the crew reported this in ACARS would suggest a possible tail strike to me (strange not to confirm it if this is the case).

ACARS mode: S Aircraft reg: .N128UA
Message label: 5Z Block id: 1 Msg. no: M36A
Flight id: UA0870
Message content:-
/71 SYDSYD 0\FLOOR PANELS NEAR SEATS 59AB LOOSE
-------------------------------------[07/05/2010 15:51]

[Matthew Chisholm]

Nigel, has there in your time ever been significant damage to a runway after a tailstrike ?

[Nigel C]

Yep, the Singapore one mentioned a few posts ago was probably the deepest gouge. Any strikes since then have generally been quite mild and left no damage to the runway, just a scrape mark.

[Grahame Hutchison]

Today's UA870 service was operated by N105UA and the aircraft involved in the incident yesterday, N128UA, has not popped up on ACARS yet. Did it depart today, or is it still being inspected ?

N105UA UA0870 08/05/2010 14:59 United Airlines B747-451 Sydney-San Francisco-Chicago

[Nigel C]

It won't be departing for perhaps a few days while the 'maintenance checks' are carried out.

[Sarah C]

Last night it was over at the QF Jet Base, near the enterance. Reg Grundy's private jet is parked along the fence so it might be blocking any view from QF Drive.

[Grahame Hutchison]

"Perhaps a few days", sounds like the "maintenance checks" may involve Spackfiller and Gaffer Tape.

[Philip Argy]

Who wants to sit in 59A or B on its next flight? :D

[Tony G]

I drove past Qantas drive on the way back from the city, only because it is the most economical route:D. There was a stand underneath with a tradesman working on the aircraft. Apart from the pilot missing out on his christmas bonus, does such an event stay with him if he/she were to seek other employment. I guess it will depend if the actual airline takes the wrap at puts it down to further training on rotating on take off :-).

[Nigel C]

Firstly I'd happily fly Row 59 for a trip to Melbourne...it's the most looked at part of the aircraft in recent history.

Tony, I've no doubt there'll be an internal review as to why the aircraft is in 'maintenance', so any impact on the flight crew will probably depend on the final outcome of the report.

[Tony G]

Okay, thanks Nigel. Who conducts the report, it will have to be someone independant of the airline and Sydney airport. Is that correct. CASA.

[Nigel C]

United will probably conduct their own internal investigation, and perhaps their ground handling company might get involved if there was any loading discrepancies.

I don't know if any other agencies would, or indeed have the need, to get involved.

[Philip Argy]

ATSB would usually investigate a tail strike I'd have thought, given its potential, and I think UA has to report it too.

[Bradley Porter]

I drive past the QF Jet Base quite regularly (2-3 times each way per day) when at work and correct me if I'm wrong but N128UA looks like it has a punctured fuselage just below the rear left door.

Looking at the UA 747 seat map it looks to be around that region or am I just seeing things ?

Brad

[Nigel C]

Perhaps seeing things. Maintenance is being carried out on the area under and surrounding the APU.

[Adam W]

ATSB investigation under way.
http://www.atsb.gov.au/publications/investigation_reports/2010/aair/ao-2010-029.aspx

[Philip Argy]

It's interesting that tailstrike is not expressly prescribed as reportable matter under the relevant legislation (the TRANSPORT SAFETY INVESTIGATION REGULATIONS).

To be 'immediately reportable' a tailstrike incident has to be within the description 'the aircraft suffering serious damage, or the existence of reasonable grounds for believing that the aircraft has suffered serious damage'.

The next category down, which is routinely reportable, does not include the immediacy requirement. It includes 'the aircraft suffering damage that compromises or has the potential to compromise the safety of the flight but is not serious damage' and also 'operation outside the aircraft's approved flight envelope'.

I'm a bit surprised that tail strike isn't explicitly prescribed as immediately reportable matter. If the extent of damage isn't immediately apparent to anyone required to report the matter to ATSB, it may be hard to fit it into an immediately reportable matter category. Something along the lines of 'contact with the runway by any part of the aircraft other than the tyres/skids' would cover the sort of strike I have in mind.

[Owen H]

Why the immediacy requirement?

Just because it isn't in the "immediately reportable" category doesn't mean the ATSB don't hear about it.

Immediately reportable has to be telephoned to the ATSB within 24hrs, with a follow up written report in 72 hours.

A Routinely reportable matter just needs the written report within 72 hrs.

I'm sure the ATSB don't want to know by telephone about every minor tailstrike, and if it is a major one then it fits into the immediately reportable by serious damage.

[Philip Argy]

Who decides whether a tail strike was serious or minor - what criteria can be applied by crew, ATC, ground staff, observers when the seriousness is not visually obvious? Was the UA tail strike serious or not?

With increased performance available in modern aircraft the rotation angles are increasing, which may increase the chances of tailstrike.

[Mark W]

United is a U.S carrier, operating under an FAA AOC - as such, the crew is bound by United reporting policy, which would be ICAO / IOSA compliant being an FAA carrier.

As such, the event is an event to be reported - to the carrier, by the crew. They would fill out an Aviation Safety Incident Report (as it is an operational occurence - "ground contact during landing or takeoff, including tail strike/over rotation and pod or wing strike").

The report would go to United Flight Safety. United Flight Safety would do an assessment and decide whether it should be reported to the NTSB (if the Pilot in Command has not ticked the "report to NTSB" box).

Once it has been received by the NTSB, they would then do their own assessment as to whether they wish to engage an investigation under Annex 13 (that is, the ATSB would investigate the matter, as it occurred in Australia) or whether the NTSB simply wished to be advised of the result of an internal United investigation (and United will do an investigation regardless).

Simultaneously, Air Services have to fill out an ESIR, which is the Air Traffic Control version of an ASIR, which may ultimately end up being reported through to the ATSB.

The ATSB and the NTSB will follow the protocols as set out in the ICAO Annex and the ATSB most likely will be guided by the NTSB given the carrier is a US carrier. Whether the NTSB wishes to have an external investigation will depend on many matters ie does United B744 operations have a higher propensity for tail strikes than other Part 121 B744 operators in the U.S, as one example.

That is the way the system works in simple terms.

[Donald H]

N128UA as UAL9918 about to depart 34L now.

Hmm. I wonder where it's off to. Passed Richmond on H202 & still going...

[Stefan Perkas]

N128UA as UAL9918 about to depart 34L now.

it is departing to Gimhae Int'l (RKPK) in Korea.

[Nigel C]

Was the UA tail strike serious or not?

It's like me asking if you're old.......

It depends on what you define as 'serious'.

Was half of the tail left on the runway?
Did it affect the flyability of the aircraft?
Were any passengers/crew in any danger?
blah, blah, blah, etc, etc, etc.

[Philip Argy]

Are they? I would think 'rate-of-climb', but not degrees of rotation as that is aircraft design specific?

Good point, Andrew. There's often an increased climb angle to go with increased performance but that angle is more often established after rotation when there's ground clearance available. Still, perhaps tail strikes are more likely if the pilot is planning a steep climb angle and inadvertently establishes that angle on rotation.

Also, in response to Mark W, United is bound by our legislative reporting requirements independently of its internal or FAA reporting requirements, so an immediately reportable incident would have to be reported to ATSB even if UA or FAA policy didn't require that. Usually there isn't much discrepancy but it's still our law that UA and crew have to comply with.

[Donald H]

Thanks Stefan. Any idea why?

[Mark W]

The point I was making is ICAO / IOSA standards from the relevant ICAO Annex, from which the Transport Regulations are derived lists "ground contact during landing or takeoff, including tail strike/over rotation and pod or wing strike" as an "operational occurence" - it is not an "immediately reportable" incident.

The crew follow their Policy and Procedures Manual with regards to Safety Reporting - which will be wholly to their carrier (the Flight Safety Department) not to outside agencies.

It is the carriers responsibility to make the assessment as to what is or must be reported, and if the requirement exits on United's Ops Spec for operations to Australia that they must independantly report any incidents to the ATSB (ie not via Annex 13 conventions [to NTSB to ATSB] because of Australian Law), then they will do so.

My experience with tail strikes is few are pilot technique - most are environmental and in aircraft like the B747, as flight crew you are not normally aware that it has occurred until ATC or another aircraft notify you - or more usually, the F/A's seated at the back call though a "loud bang" on take-off, to the flight deck during the sterile period.

[Mark W]

The ATSB is investigating -

http://www.atsb.gov.au/publications/investigation_reports/2010/aair/ao-2010-029.aspx

[Noel White]

N128UA departed SYD today at 1045 as UAL9918

[Philip Argy]

The ATSB is investigating -

http://www.atsb.gov.au/publications/investigation_reports/2010/aair/ao-2010-029.aspx

There's an echo from post 33: http://yssyforum.net/board/showpost.php?p=46450&postcount=33

:confused:

[Simon Jackman]

N128UA departed SYD today at 1045 as UAL9918

And went to RKPK. See http://flightaware.com/live/flight/UAL9918/history/20100511/0016Z/YSSY/RKPK

Repairs/inspections there?

[Fred C]

Seoul is a heavy maintenance facility for United. It went directly the for a permanent repair. A temporary repair was done in Syd by QF sheetmetal personnel.;)
It will probably take about a week.

For Philip. It is not serious damage. It was only a light scratch really. No parts fell off, apart from some shaved aluminium and the area of the fuselage is unpressurised so not structurally critical. If no-one told them about it, it would of happily flown to the states and been discovered there. Saving about 100,000 litres of fuel. However, you don't know this until you look, on the ground.:D

Maybe they could have scrambled an F/A 18 with a ground engineer on board to inspect the damage....................Lucky engineer I say.:)

[D Chan]

A temporary repair was done in Syd by QF sheetmetal personnel.

explains why a United 744 was sitting in the jetbase near the roundabout.

For Philip. It is not serious damage. It was only a light scratch really. No parts fell off, apart from some shaved aluminium and the area of the fuselage is unpressurised so not structurally critical. If no-one told them about it, it would of happily flown to the states and been discovered there. Saving about 100,000 litres of fuel. However, you don't know this until you look, on the ground.:D

Not sure if this is relevant but I thought I'd point out that UA has a metallic strip of some sort that runs along the base of the fuselage on a number of aircraft types in their fleet. Is this some sort of protection against tailstrikes because I think they would have otherwised painted the area in blue. Also noticed this type of strip on other carriers

[Fred C]

UA has a metallic strip of some sort that runs along the base of the fuselage on a number of aircraft types in their fleet. Is this some sort of protection against tailstrikes.
The strip you speak of is just an unpainted area of the fuselage. It is part of their colour scheme. I suspect it comes from the early 70's when most airlines had the bare aluminium along the bottom of the fuselage from front to rear. It was an easy way of preventing the paint scheme being damaged from the 47 various fluids that inevitably leak from an aircraft. The hydraulic fluid acts as an excellent paint stripper.
So rather than a constant cycle of clean and paint all the time they just leave it alone and polish it every so often.:D

[Nigel C]

The skin on the United B744 near the APU appeared to be no thicker than expected.

And I'm sure the pilots would appreciate the company effectively saying "Look, we appreciate you're good pilots (or so you think), but realistically we expect you're going to have a tail strike or 3 during your career with us, so we've taken the liberty of having extra thick tail strike protection added to our aircraft so you don't feel so bad if you give it a thump on departure. Just try not to use it too much, we can't afford too many repairs"

[Darryl Schlodder]

ATSB report Here (http://www.atsb.gov.au/publications/investigation_reports/2010/aair/ao-2010-029.aspx)

[Philip Argy]

There was more than trivial tail shell deformation, which probably explains the loose seats mentioned in ACARS. Oddly the ATSB report omits any mention of that ACARS transmission. I wonder if that's part of what they reviewed.

Bottom line seems to be a gust of cross and slight tail wind at VR combined with de-rated thrust led to some left column correction just at the commencement of rotation which in turn caused a spoiler-triggered momentary loss of lift sufficient to leave the a/c with insufficient ground clearance when rotate angle over-pitched to 4 degrees nose up. UA has now modified pilot training on their 744s from 3 degrees to 2.5 degrees of rotation to match Boeing's recommendations.

Basically a flukey wind condition just at the critical commencement of rotation was the primary cause, so I doubt that the (flying) PIC would suffer any opprobrium.

[Fred C]

Hi Philip,

Why do you not believe the ATSB when they say that the damage was minor?

All said, it is minor damage on a 747. That structure at the back end of the aircraft is not pressurised and is not really structural. Ultimately it is an aluminium cover for the APU.

If another departing aircraft had not mentioned it to ATC the aircraft would have flown to its destination without any problems and then the defect would be picked up during the maintenance check there. (I said this earlier, I just noticed)

The ACARS that you are referring to states that there are loose floor panels not seats. Not related to the tail strike me thinks. The pax, pilots and cabin crew would have been totally oblivious to the tail strike. For the amount of damage it would have been a millisecond touch, not audible over the engine noise.

What is interesting though is if you look at the pictures that Tony G took there is not a moderate aileron input as suggested by the ATSB report. It must have been before the photos were taken. I wonder if the ATSB was aware of the existence of the photos?:D