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View Full Version : JetX 737-800 skids off runway in Keflavik


149pax
28th Oct 2007, 10:51
The plane was vacating the runway after landing when it skidded off the runway at around 02:00 local time early this morning. The runway was slippery with snow and ice. Nobody was harmed and pax were transported to the terminal with buses.

Pictures here (http://www.vf.is/frettir/numer/33526/default.aspx)

A few hours later, 2 aircraft diverted to Egilstadir after holding over Keflavik, unable to land because of snow and ice on the runway.

BIRK
28th Oct 2007, 13:33
Not surprised, we had a bit of rain here around 7pm and then the temp. dropped to -3°, cars were skidding all over the place.

The plane was towed from the scene around 11am this morning following an inspection and currently investigators from Boeing are on their way.

blackmail
28th Oct 2007, 19:11
hello everyone,

without wanting to give any lesson to anyone or being pedantic, here is an advice i came across some years ago, regarding vacating slippery rwy's : suppose you have made a successfull landing on a slippery rwy according to your sop's (medium braking action would be ok, poor would not) . now you have to vacate the rwy. if, with idle thrust, you keep the aircraft rolling even at low speed/low kinetic energy & turn with the nosewheel steering/rudderpedals onto the taxiway, you are at risk of skidding/slipping( into the grass).
the correct technique in this case is to almost stop the aircraft straight ahead on the rwy & in order to turn the aicraft onto the taxiway, need to ADD thrust to keep the aircraft moving. the keypoint is the need to add thrust, opposed as to just rolling off. you will see that in the latter case you won't skid or slip.
happy landings,
bm

M609
28th Oct 2007, 19:18
I once had a Jaguar that tried to vacate the runway via a 90 degree exit at a fairly decent clip in snowy conditions. That ended outside the edgelamps where i powered up and skidded onto the RWY again.

Full stop, then turn is the way to go.

Packsonflight
28th Oct 2007, 21:14
Some pax complained in the local media of a terribly hard landing and that the aircraft bounched of the rwy before it landed second time.

In KEF sometimes they only sweep 40 meters of the total 60 m width of the rwy, so if you partially loose control of your ac and you are way off the centerline you might find your self in the snow. That is what I think happened there.

flying eagle
28th Oct 2007, 22:11
I dont think the landing had anything to do with it. You can see on the pictures that the aircraft is on taxiway N. So landed on rwy 02.........3000m. So it didnt skid off to the side of the rwy during the landing but when they wanted to taxi off the rwy.

Remember that pax always have alot of good ideas about what happened. So lets wait and see what the professionals have to say;)

Fly safe!

Aviator 101
29th Oct 2007, 01:18
The landing had nothing to do with this, the aircraft just skidded off as it was turning off the rwy onto taxiway N.

This happened after a loooong day for the crew, KEF-AYT-EDI-KEF.

There was a layer of ice that formed VERY quickly and later that night it snowed heavily having a breaking co-efficient 0.20 which caused the 2 757's to divert to EGS.


P.S. about an hour earlier to this incident, John Travolta landed at KEF on his B707, N707JT for a fuel stop :}

Admiral346
29th Oct 2007, 07:27
On the pictures it looks as if the nose gear is completely turned one way. Now the captain would have had to hold the tiller while shutting down engines/elec pumps for it not to turn back to neutral at least a little bit...
But then I have never flown a 737, it is a generalized assumption - maybe any of you know more about the type and its guts?
And why would Boeing specialists make their way to Iceland if it was a simple skid off in snow? As far as I know, they only consult manufacturers in case of technical problems or to reconstruct airframe/engines when torn apart in major accidents...

Nic

Tmbstory
29th Oct 2007, 11:34
It is a wonder that the Airport Authority had not closed the runway at Keflavik if the braking co-efficent was around 0.20. On the information that I used to use,it would show as Code 1, 0.25 & Below, Calculated Braking Action poor, Operational Meaning, Directional control will be poor.

Tmb

Ranger 1
29th Oct 2007, 15:05
No such thing as Co efficient of braking action exists, the Co efficent of Friction, Mu (μ) can be measured, based on this the aircraft manufacturer can give some sort of rough idea of the braking action which may be encountered.
As for Airbus I have been told they just require depth of contamination to assess likley braking action.
Braking action can vary signifcantly due to type of aircraft, technique, speed, weight of aircraft wind dircection / speed etc, therefore no machine has yet been devised to give "Braking action" yet.
A reading of .25mu is regarded as poor friction, .40mu & above good.

ICEMAN757200
3rd Dec 2007, 10:05
I was flying that day and yes we hold over KEF waiting for an improvement but we knew that conditions were not good long before. RWY 02 has an up slope gradient so you don't even have to use brakes or rev to stop the 757 at std spd (125-145 kts).

Maybe they were too fast at the end of the rwy? By our experience in winter ops we know that icy patches or low braking action + snow = trouble in KEF. JetX crew had a loooooong duty that day. The nose gear is also at an angle of 90°. That will not do the turn on a slippery taxyway. You first have to try to reduce the angle to regain control, but all this is only speculation as we are still waiting for the report.

Mungo Man
3rd Dec 2007, 10:32
Any other links to pictures? I can't get anything out of the link given.

ICEMAN757200
3rd Dec 2007, 12:29
http://vf.is/ljosmyndir/safn/987/1/default.aspx
PUSH ON "Næsta" TO SEE THE REST YOU HAVE ABOUT 10 PICS.

ICEMAN757200
3rd Dec 2007, 12:31
By The The Way Rwy 02 Is 10000´ft Long

ICEMAN757200
3rd Dec 2007, 14:42
Txwy N-4 Is A 90° Turn At The Very End Of Rwy 02. I Don´t Remember Exactly The Forecast But We Had Snsh Vc , Ba Was Ok On Rwy 02 But With Icy Patches, Braking Action Poor On Txwys Wind 250°/40g50kts. I´ve Landed 757 At Mldw , Autobrake Off, And Idle Rev On Rwy 02 Acft Usualy Stop By Itself Before Txwy Kilowich Is Aprox 600 Mtrs Before Txwy N-4 Or Rwy 20 Thr, Same Thing Anyway

ICEMAN757200
3rd Dec 2007, 15:00
When Jetx Landed Conditions Were Similar But Wind Wasn´t That Stron About 30kts Cw And Some Tail Wind To I Think

BOAC
3rd Dec 2007, 15:15
I'm certain I posted this in post #2 but Danny deleted it so here goes again! The ends of all runways in KEF are ungrooved in the last 900m and although BA may be perfect on the runway it can be zilch on the last 900m. I had a 'near grass track' experience there a couple of years back in exactly the same place which prompted KEF ATC to actually own up to the condition of the ends by NOTAM as it was a well-kept 'secret' before :mad:.

I assume the lack of grooving has something to do with the run-out on the RHAGS but I am not sure?

calypso
3rd Dec 2007, 18:41
At those wind speeds and with icy taxiways you may skid into the grass even if you have stopped. I remember a few years ago in Kef under similar conditions aircraft spinning out of control in the ramp. They came with bags filled with hot sand to chock them up.

iko wapi choo
3rd Dec 2007, 23:06
Flight was being operated on behalf of Astraeus

sevenstrokeroll
3rd Dec 2007, 23:15
Blackmail:

agree with you buddy and I'll add...don't stow the reversers too quickly. they might come in handy. (all warnings of course)

stop completely on the real runway.

when you start moving again, check the braking action and if there ain't any, at least you have time to think