Airbus 310 accident in Congo fully caught on camera...

[JanetFlight]

Please mods i recognize that one thread/topic its already opened about this very accident, however i think the importance here could get some nice interesting comments regarding operationals/pilots/lessons learned, etc.,,,,for those who have a FB account...wow, tricky things here:

https://www.facebook.com/luc.ntambwa/videos/1041292502560848/

Updated...YT:

https://www.youtube.com/watch?feature=player_embedded&v=CAGIQEMyPQA

[Doors to Automatic]

Interesting video in that contrary to earlier reports the aircraft does not appear to touch down excessively late, nor is it too high over the threshold. The reason for the overrun seems to be high landing speed plus, maybe, the condition of the runway.

[Chris Scott]

Runway may have standing water: certainly very wet, and might even be classed as "contaminated". Aquaplaning quite likely. Touchdown position looks reasonable enough, but full reverse selected very late. Hard to see what flap has been used for the landing. Also hard to judge the speed, but it looks higher than normal (bearing in mind the A310 is not a small a/c). No windsock visible to assess W/V.

[Airbubba]

Touchdown position looks reasonable enough, but full reverse selected very late. Hard to see what flap has been used for the landing.

And, hopefully, autobrakes to Max. On some A310's the top square button is guarded, on others it isn't as I recall. Inadvertently select Max brake landing with a light aircraft on a dry runway and any economy pax with loose seatbelts get upgrades to the front cabin for the taxi in. :eek:

Having said that, some 'bus operators always used autobrakes, others never did in my experience.

Looks like the spoilers did deploy in the video.

[safelife]

Looks like braking action was not much better than poor, autobrake selection wouldn't make a lot of difference here.
Seems they touched faster than aquaplaning ground speed, and stayed above that at least until full reverse was effected.

[Chris Scott]

Must admit I can't see if the ground spoilers have deployed immediately on touchdown. Haven't got my (early) A310 course notes to hand, but I presume automatic deployment is signalled by main-wheel spin-up? The latter, of course, may not happen on a flooded surface, and the touchdown seems to be fairly gentle: a firm touchdown is desirable on a wet surface. Lack of main-wheel spin-up due to aquaplaning, as safelife points out, would be a double-whammy: no braking capability and no ground spoilers. (Ground spoilers dump the residual lift of the wing, as well as providing valuable drag in the early stages of the landing run.)

Not sure at what point in the landing run Airbubba can see the ground spoilers, but I think their second-line deployment signal comes from the pilot selection of reverse idle. That may have been done immediately after touchdown, but I can't tell from the video. (Can someone current tell us if reverse selection also requires main-wheel spin-up? If that were the case, it could explain why full reverse was not achieved until the a/c is abeam the camera.)

Re use of autobrake, the MAX selection is only used for rejected take-offs in my experience. On the A320, MED (medium) is standard for landing on wet or contaminated runways, and I think the same would apply to the A310. It goes without saying that brakes are useless until the wheels spin up.

[Doors to Automatic]

Note the time taken for the aircraft to pass between the 1000ft and 500ft markers at the far end. For reference, at 60mph it would take around 6 seconds.

[silvertate]

In my experience, aquaplaning due water depth is not the problem, oil and rubber are the key. If there is a little rain, after a long hot summer, the oily surface can become like an ice-rink.

I landed at xxxx in the Mediterranian, with barely a spatter of water on the runway, and max braking did absolutely nothing. I truly thought the brakes had failed. So we cruised down the runway at the same speed patiently waiting for the inevitable incident, until reaching nearly 3,000m down the runway which is not used much and had no deposits. And then the brakes grabbed and stopped us within 500m.

A complaint was raised, but I did not notice any difference to the surface deposits the next time I flew there.

[wanabee777]

In my experience, aquaplaning due water depth is not the problem, oil and rubber are the key. If there is a little rain, after a long hot summer, the oily surface can become like an ice-rink.

Though water depths over 1/2" can definitely be problematic, I fully agree with your observation regarding oil and rubber deposits on the runway mixed with a little water.

Been there. Done that. Had the ever luv'n ****e scared out of me.

[Chris Scott]

Quote from Doors to Automatic:
"Note the time taken for the aircraft to pass between the 1000ft and 500ft markers at the far end."

Think I can see the 1000ft (time about 0:22), but the 500ft would be guesswork... (~ 0:24?).

It'll be interesting to see what the BEA have to say when they emerge from the Xmas break. Presumably they will send a team, and be responsible for the DFDR/CVR retrieval - in the event they haven't already been nicked or tampered with... (The QAR cassette would also be invaluable, but that's even less likely to be unsullied.)

[Airbubba]

Re use of autobrake, the MAX selection is only used for rejected take-offs in my experience. On the A320, MED (medium) is standard for landing on wet or contaminated runways, and I think the same would apply to the A310. It goes without saying that brakes are useless until the wheels spin up.

You're right, I'm probably thinking of recent FAA guidance on the widebody Boeings that might not be used on Airbus freighters in Africa.

Perhaps in response to a Southwest B-737 overrun at MDW years ago, we've now got tables of minimum autobrake settings for landing on slippery runways. In some situations with a tailwind, short runway and/or braking reported fair, the table can go to MAX at a normal landing weight. I think I've only used MAX outside the sim once, at EWR landing on runway 11 with strong favorable winds but marginal runway conditions.

In my experience, aquaplaning due water depth is not the problem, oil and rubber are the key. If there is a little rain, after a long hot summer, the oily surface can become like an ice-rink.


One place I've sure seen that is BOM. The pavement on runway 09-27 is over 11,000 feet long but the oil and rubber deposits coupled with the rain and heat can make things challenging. And periodically, 09-27 is closed for maintenance and hopefully rubber removal. Then, you get to wave at the folks on Trombay Hill as you shoot the VOR Rwy 32, especially if you line up on the runway centerline a little early.

[JammedStab]

Is it me or does the speed seem very high? I wouldn't say that it was heavy rain at the time and certainly no heavier than normal ops seen around the world. Runway does look a bit short.

[RAT 5]

BA L10-11 many years ago at LBA. Rubber deposits + wet runway?

[Thrust Augmentation]

Is it me or does the speed seem very high?


Yes, looks more like a touch-n-go up to a certain point. Take a look at the nose high attitude at around 13 seconds, not much braking there? Looks more like an RN F-4K ready for launch.

[Wageslave]

Does the Book not say "Thou shalt not" on contaminated runways?

So why is anyone surprised at the result when some numptie does?

Look at the curtains of water being flung up above the wing - that runway isn't just "contaminated", it's flooded!

Rubber deposits + wet runway?
Wet! Wet??? !!!!!! You think that's "wet"? You are having us on, aren't you? Please say so...



My completely unprovable tuppenyworth is that the touchdown doesn't look at all positive, indeed it looks like a greaser. In those conditions he should have thumped it in and I don't believe he did. I wonder if the brakes ever got a chance.

[Doors to Automatic]

Chris - correct 0:22 and 0:24

By my calculations around 21 seconds to cover 6000ft, meaning 17,142 feet per minute, or around 1 million feet an hour. With 5280ft in a mile that gives an average ground speed of 194mph (169 kts) during the entire landing run.

The runway is actually very slightly longer so the speed was even higher.

It seems like a very high approach speed followed by virtually no deceleration.

[Chris Scott]

The accident is now included in the BEA's summary of incidents and accidents in week 52 of 2015 (only on the French-language site):

http://www.bea.aero/fr/enquetes/2015/2015.semaine.52.pdf

It lists SOB as only 5, with 8 fatalities and 9 serious injuries. Presumably the 5 on board would be flight and cabin crew: all uninjured (?). Damage to the airframe "substantial". They attribute the information to the local authorities (of the Democratic Republic of the Congo).

One imagines the landing weight would have been very low, unless they were tankering fuel. Does anyone know if fuel is available at Mbuji-Mayi?

[Centaurus]

Difficult to accurately judge from the photo, but appears to be a relatively long time between touch-down and actuation of full reverse thrust. Readers know that reverse thrust is most effective at high speed. This means a fast manual selection of the reverse levers to full reverse immediately on touchdown. On slippery runways, and if wheel spin-up is slow, automatic speed brakes may not operate and it is necessary to raise the speed brake lever manually immediately on touch-down if max stopping capability is to be realised.

In the simulator it is often observed that some pilots lift the reverse levers up slowly as if to graduate the amount of reverse. It is a faulty technique and often results in delayed spool up in reverse. Obviously this is undesirable on a slippery runway where wheel braking efficiency can initially be very low, despite auto-brakes operating. Full and immediate reverse may be the only effective retarding force after touchdown and until the brakes begin to bite. This is where good quality simulator training on wet runways is vital.

The video should be used as an excellent training tool as it is a very rare display leading to an actual accident. The following link depicting several stills where the aircraft finally stopped, is borrowed from another thread on the same subject called How to lose two A310 before Christmas.

http://avherald.com/h?article=49150489&opt=0

[Chris Scott]

Quote from Centaurus:
"Difficult to accurately judge from the photo, but appears to be a relatively long time between touch-down and actuation of full reverse thrust. Readers know that reverse thrust is most effective at high speed. This means a fast manual selection of the reverse levers to full reverse immediately on touchdown. On slippery runways, and if wheel spin-up is slow, automatic speed brakes may not operate..."

Cannot disagree with any of that, as it more or less paraphrases parts of what other posters, including myself, have been discussing for the last 36 hours! (See posts above.) Can we assume you are using a small-screen internet device? :sad:

Quote:
"On slippery runways, and if wheel spin-up is slow, automatic speed brakes may not operate and it is necessary to raise the speed brake lever manually immediately on touch-down if max stopping capability is to be realised."

That sounds like good advice for some second-generation jets. However, in the case of relatively modern a/c, like the A310, the airbrakes are designed to go into ground-spoiler (lift-dumper) mode, in which the spoilers are raised to a higher angle than possible in speedbrake mode. On the A310, ground-spoiler mode raises all seven spoiler surfaces on each wing to 50 degrees. Speedbrake mode uses only four, and at a maximum of 20 degrees for the inboards and 45 deg for the outboards.

AFAIK, ground-spoiler mode cannot be commanded ad-hoc by the crew. They must arm it prior to landing, by raising a knob on top of the speedbrake lever, and then rely on its automatic deployment. (If the crew has failed to arm it, deployment can also be achieved if reverse is selected on at least one engine.) Deployment is normally achieved by the signal of main-wheel spin-up on touchdown (provided throttles at idle). However, my early manual gives bogie (truck) rotation plus RA less than 5 ft as a back-up signal, after a delay of 3 seconds.

Spoilers extension can all be monitored on the ECAM F/CTL page. If they fail to deploy, the problem with pulling the speedbrake lever is that - IIRC - the result will be full speedbrakes only (see above). They will have little effect compared with ground spoilers.

[Chris Scott]

Quote from Doors to Automatic:
"By my calculations around 21 seconds to cover 6000ft, meaning 17,142 feet per minute, or around 1 million feet an hour. With 5280ft in a mile that gives an average ground speed of 194mph (169 kts) during the entire landing run.
The runway is actually very slightly longer so the speed was even higher.
It seems like a very high approach speed followed by virtually no deceleration."

Yes (until the end of the runway). Now why didn't I think of doing that? It certainly lends some support to the suggestion elsewhere that - following a very fast approach, possibly with limited flaps, the PF - realising there was insufficient distance remaining on a slippery surface - may have decided to go-around at or soon after touchdown. SOPs vary, but if - for example - the PNF is responsible for selecting the reverse on his own initiative after touchdown, as is (or at least used to be) the case in one large British airline, the PF can find himself faced with a fait-accompli. Any subsequent attempt to re-select forward thrust is likely to result in a grand cock-up...

One of the key points in the investigation will be how much fuel was remaining.

[Feathers McGraw]

Looking at the aircraft photos on avherald.net it looks like not much flap is selected, possibly a setting more in keeping with take-off. That would certainly tie up with the relatively high speed landing and not provide additional much-needed drag on landing.

[Empty Cruise]

Maybe my eyes are deceiving me, but it looks like the aircraft is rotated -as in a baulked landing attempt - just before the camera pans left and we lose sight of the aircraft for a few seconds.

[Halfnut]

Other then dry runways you are on your own -

http://www.faa.gov/other_visit/aviation_industry/airline_operators/airline_safety/safo/all_safos/media/2015/SAFO15009.pdf

[parabatix]

https://www.youtube.com/watch?v=0pl8jwpXxJE

A not very nice view of the carnage that followed. RIP

[Chris Scott]

Thanks parabatix,

The post-accident video clearly shows the flaps at a take-off or go-around setting: either 15 deg or 20 deg. Unless things have changed since my day, there are 4 flap positions: 0, 15, 20 & 40. The normal landing setting would be 40 deg, and - except in the case of a failure with an inability to divert - it would be unthinkable to land on a short, wet runway with anything less.

This lends support to the opinion of several posters that one or both crew members may have tried to initiate a go-around after touchdown - perhaps due to excessive airspeed and the realisation that an overrun would otherwise be likely. The only alternative is that the crew partially retracted the flaps after the a/c left the runway, which is highly unlikely. The standard go-around procedure is to select TOGA thrust, and retract the slats/flaps one step. (If the ground-spoilers have already deployed, they will retract automatically.)

An aborted go-around could have resulted, as I've speculated previously, from a misunderstanding between the two pilots. For example, if the PF elected to go-around just after the PNF had selected reverse idle, that would cause confusion that might take several seconds to resolve. The PF would know that it would take valuable seconds for forward thrust to be reinstated before he could select TOGA thrust for the go-around.

But, except for my first paragraph, the above is all speculation - particularly as we don't know the SOPs for throttle handling in the airline concerned. We do know, however, that full reverse was not achieved until about 10 seconds after nosewheel touchdown, at which point fewer than 2000 feet of runway were remaining. (That is not to suggest that full reverse is the dominant factor in deceleration, even at high speeds. The wheel brakes normally do most of the work. But on a slippery runway, any crew would want to use it as soon as possible.)

Parts of the video are not for the faint-hearted... The slats are extended, as expected (setting indeterminate). The spoilers seem to be retracted, but this could have been done instinctively by one of the pilots as the a/c came to rest.

[Hotel Tango]

That video clip demonstrates a difference in culture to many other parts of the world. I think that over here, instead of a photo frenzy, every effort would have been made to cover the bodies asap. I suppose they are more accustomed to seeing death than we are.

[22/04]

Never been to Africa except the South.

I suppose RESA boundary fence are silly questions?

[skyship007]

I suspect a lot of different factors might have been involved, for example:
1/ Vref too high
2/ Touchdown too late (No attempt to smack it down)
3/ Serious standing water
4/ Rubber deposits and no grooves
5/ Lack of fuel to divert, or get it down itis.
6/ Far Eastern brake pads
Sad about the loss of life.