777-300 Landing Tailstrike 11 Dec 2018 in Hong Kong

[FCeng84]

I just learned of this event today. A quick look through PPRUNE rumors and news did not reveal any previous thread about this one.

https://www.flightglobal.com/news/articles/air-canada-777-300er-suffers-hong-kong-tail-strike-454428/

From what I saw it seems the tail damage was fairly extensive. I'm interested in both the status of this bird and any details anyone may have about that landing.

[WillFlyForCheese]

Pictures on Twitter here: https://twitter.com/TomPodolec/status/1072434605083582466

[DaveReidUK]

Some discussion of it in this (https://www.pprune.org/rumours-news/616325-tailstrike-ural-airlines-ufa.html)thread.

[terminus mos]

What an unfortunate registration C-FITW - In the North Sea offshore helicopter industry in means controlled flight into terrain (water).

[andy148]

Ironic that i only watched a documentary on YouTube yesterday about rampant fatigue at 'Air Canada', i wonder if it had anything to do with this? They did mention that Canada were in the process of reducing the hours form 1200 (iirc) to bring them in line with the FAA as they had the third highest flight hours . Id be interested to hear other peoples thoughts on it.

[FullWings]

Interesting. The 777-300 has software tailstrike protection which reduces elevator deflection but it still has a tail skid, strike detector and a checklist, so obviously not thought to be infallible...

[oceancrosser]

Landing tail strikes usually affect a part of the fuselage forward of the tailskid (if installed) due to gear strut compression. These can cause significant damage.

[shakealeg]

Full Wings. Depends on model. Earlier ones had tail skid and no protection and later ones have no skid and a computer to protect. However one thing is for sure.. nothing is infallible.

[DaveReidUK]

Full Wings. Depends on model. Earlier ones had tail skid and no protection and later ones have no skid and a computer to protect.

I believe all -300ERs have some degree of tailstrike protection embedded in the flight control software. Later production aircraft have enhanced protection, which enabled them to be built without the tailskid, resulting in significant weight savings when all the extra structure needed for it was eliminated.

Earlier aircraft can have the software upgrade and the tailskid removed, though the weight savings are obviously less. I think a similar SB is also available for non-ER -300s.

[etudiant]

I believe all -300ERs have some degree of tailstrike protection embedded in the flight control software. Later production aircraft have enhanced protection, which enabled them to be built without the tailskid, resulting in significant weight savings when all the extra structure needed for it was eliminated.

Earlier aircraft can have the software upgrade and the tailskid removed, though the weight savings are obviously less. I think a similar SB is also available for non-ER -300s.

Interesting to have another 'protection' system, a la MCAS, that obviously limits the pilot's inputs. Boeing, unlike Airbus, used to have a philosophy that the pilot should be able to bend the airplane. Clearly that is no longer the case.

[stilton]

Interesting to have another 'protection' system, a la MCAS, that obviously limits the pilot's inputs. Boeing, unlike Airbus, used to have a philosophy that the pilot should be able to bend the airplane. Clearly that is no longer the case.


I stand to be corrected but I believe Boeing’s tailstrike protection system is a ‘soft’ limiter
You know it’s there when it operates but you can ‘pull through it’ if you have to


like all their FBW limiting systems they can be overridden by applying more force if necessary

[etudiant]

I stand to be corrected but I believe Boeing’s tailstrike protection system is a ‘soft’ limiter
You know it’s there when it operates but you can ‘pull through it’ if you have to


like all their FBW limiting systems they can be overridden by applying more force if necessary

Hope that you are right, that I was maligning Boeing unfairly in this instance. Can anyone give a definitive answer?

[vilas]

like all their FBW limiting systems they can be overridden by applying more force if necessary When they can be overridden they get overridden even when not required.

[Seat4A]

HK Air Accident Investigation Authority released its Preliminary Report. I don't have enough posts to include the link here.

Interesting read. I was on that AC 15 on Dec 11 2018. It's one of my regular routes.

[flyhardmo]

http://www.thb.gov.hk/aaia/doc/Aircraft%20Accident%20Preliminary%20Report%201-2019(rev)e.pdf

[Seat4A]

@flyhardmoThank you for posting the link.

My recorded notes on Dec 11 upon arrival had some of the same details noted in the prelim report. Plus flying as pax, we had different views rolling to the right while seated just in front of the wing on the starboard side. Knew there would be damage with the first hit. We also felt more than one bounce. She was already at the Haeco facility prior to my departure on connecting flight. She is still there.

[Callsign Kilo]

According to the preliminary report, this was the FOs first landing in the 777 since simulator (type) training. Although the report notes that Air Canada’s SOP is to disengage the autopilot at 400 agl, I’m pretty confident that this isn’t enough time to get a ‘feel’ for the aircraft; especially for someone so new to it.

[FCeng84]

Report also indicates late change to parallel runway. Sounds like an appropriate situation for extra briefing to be ready for and execute a go around if not sufficiently stable. Had the FO had any time on that flight hand flying prior to disconnect at 400 ft? The cost of this event could have paid for a lot more training including some hand flying in the real thing. With a high enough pilot gain any airplane can be made to PIO.

[Sqwak7700]

How come Cathay’s tailsyrike in HKG got no report released by CAD?

[Chris2303]

How come Cathay’s tailsyrike in HKG got no report released by CAD?

Report is issued by the accident investigation unit of the state of occurrence unless delegated to the state of registration

[vilas]

Considering that the PF was getting the feel of the aircraft first time and below 200ft. aircraft was laterally disturbed requiring correction which wasn't adequately coming from the PF and CM1 had to intervene he might as well have postponed the first landing of the FO to another day and completed the landing himself. Two people trying to maintain the center line nobody seems to have flared. 777 is a big aircraft to successfully do all that at such a low altitude. What happened to stabilized approach concept?

[DaveReidUK]

Interesting that, judging by the photos in post #2, the damage was sustained roughly in line with the bulk cargo door - several frames forward of the tailskid.

[Capt Fathom]

Why is that interesting?

[suninmyeyes]

With a high rate of descent in conjunction with a nose high pitch attitude,

Interesting and unusual. I am aware of a tail scrape on a B777 landing due to the Vref speed manually inputted incorrectly. (Why do some people insist on manually knocking off a bit of weight for the descent and approach and typing in a revised landing weight instead of selecting the present weight figure which at worst will give you a 2 knot greater speed?)

My experiences of someone's first landing on type after a long flight is a tendency to under flare and a firm arrival. I wonder if the trainee on this flight flared late and continued to raise the nose as the wheels touched, possibly aided by a Captain rapidly increasing back pressure. I'd be interested in what the nose pitch was when the tail scraped. For a normal landing the nose is raised to no higher than 5 degrees and the tail would not scrape until at least 8 degrees pitch or so. An extended flare can lead to a tail strike but that would not give a firm landing.

[DaveReidUK]

Why is that interesting?

I guess it's just my natural curiosity.

YMMV :O

[Seat4A]

Just saw her the other day at HKIA, still outside Haeco, but after 60 days there, she just landed at YYZ as AC 2328

[physicus]

What does a carrier like AC do with a pilot that caused that kind of of damage (or was at least in part responsible)?

[FlightDetent]

YMMV :ODave, is seems quite typical of landing and bounce scrapes. The tailskid is mounted to protect the impact point against takeoff tailstrikes. With MLG oleos extended, the geometry is different.

[stilton]

What does a carrier like AC do with a pilot that caused that kind of of damage (or was at least in part responsible)?


Depends


We had a tailstrike event with a 777 on departure at my airline, there was extensive damage to the aircraft


In that case the crew went through some retraining in the sim and went back to the line


If either one of the Pilots had a ‘record’ of negative events there may have been a different outcome but management was very fair, obviously it wasn’t intentional so why throw away someone’s invaluable experience?


Of course it depends on the individual Airline

[oceancrosser]

Dave, is seems quite typical of landing and bounce scrapes. The tailskid is mounted to protect the impact point against takeoff tailstrikes. With MLG oleos extended, the geometry is different.

Spot on. Pretty much applies to all the stretched Boeings.

[EI_DVM]

Although the report notes that Air Canada’s SOP is to disengage the autopilot at 400 AGL.

Surely that cannot be an actual SOP? That sounds exceptionally prescriptive and in today's more enlightened environment of encouraging hand-flying/reduced levels of automation/raw data etc when appropriate for the prevailing conditions, it sounds almost draconian for a western airline and totally out of line with best practise.

[CanadianAirbusPilot]

Surely that cannot be an actual SOP? That sounds exceptionally prescriptive and in today's more enlightened environment of encouraging hand-flying/reduced levels of automation/raw data etc when appropriate for the prevailing conditions, it sounds almost draconian for a western airline and totally out of line with best practise.
You're correct. Our FOM encourages hand flying i am not on the 777, but what the boys and girls do after being in the air for 16 hours I am not sure I am on the 320. Some pilots disengage pretty late. Others will turn everything off above 10,000 when appropriate. I subscribe to the later personally, I like flying the bus raw data, AP and A/THR off I feel more in the loop of current performance. Some others will take over at minimums and leave A/THR engaged.

Regarding what happens to said pilot, my understanding is the skipper was close to retirement so unfortunately this was his last landing. The PF will probably get further coaching and released back to line indoc (if not already having done so).

[777JRM]

https://cimg8.ibsrv.net/gimg/pprune.org-vbulletin/1365x904/4d6d7eb8_098a_42af_815e_5be07c26213a_6374d5dd6dfda74b0ff2e18 f942cd81bd78dcb08.jpeg

[greenfields]

Others will turn everything off above 10,000 when appropriate. I subscribe to the later personally, I like flying the bus raw data, AP and A/THR off I feel more in the loop of current performance.

See how many times you do that after doing a ULR flight. I'm tipping not even one. :ok:

[fdr]

Interesting and unusual. I am aware of a tail scrape on a B777 landing due to the Vref speed manually inputted incorrectly. (Why do some people insist on manually knocking off a bit of weight for the descent and approach and typing in a revised landing weight instead of selecting the present weight figure which at worst will give you a 2 knot greater speed?)
.

Because our system of box ticking compliance driven standards results in some parts of the program having a vice like grip on the trivial, without recognition of the attendant elevation of risks. Concentrating on one minor part of the system results in opportunity to miss the big picture items, woods v trees

[CanadianAirbusPilot]

See how many times you do that after doing a ULR flight. I'm tipping not even one. :ok:
You’re probably right. For now I have no interest in overseas flying. One day the desire to make more money may have me bidding the 777/787 but for now, day flying and home most nights has me enjoying the non UlH flying.

I just wanted to correct the comment that AC mandates AP usuage. They encourage hand flying and each pilot can decide what he or she does with the automations with a few exceptions (CAT 2/3, RVSM and a few RNAV 1 operations where AP is encouraged but FD are mandated)

[Pilot DAR]

Ground Contact Angles - Normal Landing

I think that ground contact at the angle of any of those lines would be an abnormal landing?

[Jet Jockey A4]

You’re probably right. For now I have no interest in overseas flying. One day the desire to make more money may have me bidding the 777/787 but for now, day flying and home most nights has me enjoying the non UlH flying.

I just wanted to correct the comment that AC mandates AP usuage. They encourage hand flying and each pilot can decide what he or she does with the automations with a few exceptions (CAT 2/3, RVSM and a few RNAV 1 operations where AP is encouraged but FD are mandated)


Just asking... You "must" use the A/P for a CAT II approach at Air Canada? Is this type dependant?

[giggitygiggity]

In my major european airline, we have to fly CAT II with the AP in also. I assume it was a fairly common rule now? A few years ago it said we SHOULD fly CAT II with an AP and it should never be planned to be manually flown, now we don't practice it in the sim so the rules have changed meaning that anything tighter than CAT I (eg LTS/OTS etc) must be flown with the automatics.

[fdr]

I think that ground contact at the angle of any of those lines would be an abnormal landing?

Most 773 touchdown attitudes are between 3.5 and 5.0 degrees. higher than that is the result are worthy of analysis. To get a tail strike needs an extended float bleeding speed excessively, (each 5kts is another degree of attitude more or less) or an abrupt late flare at a low speed. A bounce and attempted flare to cushion the landing will result in reduced tail clearances. A very low touchdown sink rate can result in a pitch up on WOW logic triggering spoiler rise. The B777 is better than previous Boeings in that regard, but there is a pitch up moment at that time unless the gear has completed the ground stroke.

Crosswinds positively correlate to reduced tail clearances, although my data on that is at least 5 years out of date.

The lowest clearances that occur in normal operations is on takeoff, where a Vr error, or loss of airspeed following commencement of rotate can be nasty, but historically most strikes occur on landings where there is more clearance on a normally executed landing, but there is more variability in technique and dynamics resulting in speed variation in the flare, and variation in the pitch rate and attained pitch.

FWIW, adding a HUD makes it much easier to ensure that flares are appropriate, FPV remaining on the touchdown zone etc...

[Jet Jockey A4]

In my major european airline, we have to fly CAT II with the AP in also. I assume it was a fairly common rule now? A few years ago it said we SHOULD fly CAT II with an AP and it should never be planned to be manually flown, now we don't practice it in the sim so the rules have changed meaning that anything tighter than CAT I (eg LTS/OTS etc) must be flown with the automatics.So assuming you have a total A/P failure (unlikely) and the WX is CAT II for your destination and your alternate is 500 miles away you go to your alternate even if the aircraft was certified to be CAT II hand flown?

What about those aircrafts with HUDs that are certified/capable to be hand flown to CAT IIIA minimums?

The C Series now Airbus 220 was certified to be hand flown to CAT IIIA minimums a year ahead of its Auto land certification.

The irony here in Canada is that a private operator can shoot and ILS CAT I to the same visual limits (RVR 1200' / 1/4 of a mile vis) except the DH will be typically 100 feet higher (200' agl versus 100' agl) and this to runways without the same lighting systems requirements as on a CAT II runway.

Seems not allowing aircrews to hand fly down to what an aircraft is certified to can restrict daily operations when needed.

[Chu Chu]

Maybe the angles are different for a hard landing?

[fdr]

Maybe the angles are different for a hard landing?

The geometry limit graph is a rigid body solution, e.g., it is a static clearance outcome. The dynamic solution can be different for other parts of the aircraft. The compressed oleo geometry is a limit if the gear stays in one piece. The aft body does have bending under inertial load and from the interaction of gear load v elevator/horizontal stab loads, but they are not very large. A significant change does occur for the engine cowl clearance as a response to gear loads and timing of the resultant torsion of the wing box and the engine pylon. I have investigated a couple of landings where a pod scrape occurred well within the geometry envelope, but the pod still moved enough with the wing to touch the pod on the ground. The process of those institutionally was interesting, the system wanted to hang a bunch of crews trying to ascertain why they had not picked up the damage on the intervening flights, as in both cases they didn't want to accept that the last crew who did hard landings with low pitch attitude and roll were responsible. The OEM responded in both cases confirming the geometry was a static model... which raised furore within the company as being misleading to their fine crew. 3g landings on one wheel near a geometry limit for both pitch and roll may result in a visit to the spray booth.

[CanadianAirbusPilot]

Just asking... You "must" use the A/P for a CAT II approach at Air Canada? Is this type dependant?

On the Airbus fleet it is, I think that is standard for Airbus ops though. As soon as you kick off the AP the approach capability degrades to CAT 1. In Canada I believe you require a HUD to do a CAT II or better hand flown. The only aircraft with a HUD are the 787s and the 737s. The A220 will come with dual HUDs installed. Never flown the 787 or 737 so I can't speak for those.

[Jet Jockey A4]

On the Airbus fleet it is, I think that is standard for Airbus ops though. As soon as you kick off the AP the approach capability degrades to CAT 1. In Canada I believe you require a HUD to do a CAT II or better hand flown. The only aircraft with a HUD are the 787s and the 737s. The A220 will come with dual HUDs installed. Never flown the 787 or 737 so I can't speak for those.

Auto pilot, auto throttles or HUD not required to fly a CAT II by hand... Some Dash 8s, Bombardier CRJs and some older B727s in some airlines in the USA way back in the 80s or early 90s with the proper equipment could be hand flown to CAT IIIA minimums.

[aterpster]

Fail-active autoland made CATII safe,

[Seat4A]

HK AAIA Final Report just issued. Interesting reading.

https://www.thb.gov.hk/aaia/doc/Air%20Canada%20AC15%20Final%20Report%2028%20Dec21.pdf
.

[anxiao]

As to be expected. Don't rock the boat, a good solid PIO that CAD can hang their hat on and a few minor training and operational recommendations. AC off the hook and HKIA without a stain.

Might I make a couple of recommendations for future operations?

1) Do not expect a pilot after a 17.41 duty day at a body time of 0200 to carry out his first landing on his first widebody into an unfamiliar destination. They will be as sharp as a beachball and task saturated at the moment the autopilot comes out. Equally do not expect a 64 year old training captain to be sharp enough to catch a trainee's error under the same fatigue conditions.

2) If there is a windshear warning 12 minutes before an aircraft lands of minus 25 knots it might be a smart idea to transmit it to landing aircraft. To then dismiss it in the report as not relevant is strange.

3) ZFT to widebody training on first landing, it might be a good idea to mandate to take the autopilot out above 1,000 ft so that the pilot can assess the roll rate and feel of the aircraft and experience the peripheral vision in roll which is not experienced in a simulator.

4) if ATC has just seen an incipient aluminium dust cloud at the touchdown point on a landing runway, it might be smart to send a checker car with a brush to do a runway inspection at the first available opportunity.

And so on add infinitum until the next incident/accident. Fatigue is brushed under the mat and the most economical way of training pilots wins the day.

[FMS82]

It seems very strange that a new joiner on a specific type gets his/her very first feel of the airplane on (very) short final. A short final this person isn't familiar with at that.

Give people some stick time climbing out, then gradually build out the exposure, including some proper time hand flying the long approach. On the candidate's first landing, the TC should be sharp as a razor to take control at the first sign of trouble. Especially on the 300, which is a bit less forgiving on pitch deviations

What should have been a nice and memorable training experience for the FO, now potentially has significantly dented their confidence. And I can't help but feeling for the captain. What an inglorious way to end a career. I understand this was his last landing as he was close to retirement.

[punkalouver]

What should have been a nice and memorable training experience for the FO, now potentially has significantly dented their confidence. And I can't help but feeling for the captain. What an inglorious way to end a career. I understand this was his last landing as he was close to retirement.

Reminds me of the captain for a jet cargo operator that descended into trees a few miles short of the runway(prior to climbing out again) on his last flight. In that case, I was told the company gave him one more flight so his last flight would be a good one.