Factual info from ERj145 off Runway in YOW Sept 2011.

Heres a cliff note...

"Just before touchdown a heavy downpour obscured the view of the crew, they perceived the aircraft was dramatically increasing its sink rate and the captain applied maximum thrust on both engines resulting in a master caution and a warning that flaps were not in takeoff configuration. The maximum thrust was maintained for about 7 seconds.

The aircraft touched down smoothly about 2700 feet past the runway threshold at 119 KIAS, the airspeed however was increasing and the aircraft became airborne again. The aircraft touched down a second time at 3037 feet past the runway threshold at 125 KIAS and about 20 feet to the right of the runway center line, the speed peaked at 128 KIAS, the nose wheel touched down and the thrust levers were pulled to idle. Both outboard spoilers immediately extended after touch down, the inboard spoilers deployed 8 seconds later but retracted abotu 4 seconds later again, the outboard spoilers retracted about 20 seconds after deploying.

After the nose wheel had touched down the captain applied maximum braking, the crew however noticed almost instantly that the aircraft began skidding. The captain requested the first officer to apply maximum braking, too, however no noticeable deceleration was felt and no significant brake pressure was indicated. Brake pressure suddenly increased to its maximum about 18 seconds after the outboard spoilers had extended, the aircraft skidded to the left with application of full right hand rudder remaining ineffective, a spray of water from the wheels rose up to 22 feet above runway surface and about 300 feet past the aircraft, the captain applied emergency braking however stowed the emergency brakes again after no noticeable deceleration was felt."
 
SFCC/UND said:
Hence the reason we don't fly to Canada anymore
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I dunno, the cliffs notes that I read below seem to indicate a failure to go around when the aircraft was still airborne 2500+ feet down the wet runway, not necessarily a fault of the Canadians.
 
I won't deny that having thrust reversers would have helped immensely but why not just go missed and give it another shot when the weather cleared? I don't think it would have been a fun ride for crew or passenger.
 
Roger Roger said:
I dunno, the cliffs notes that I read below seem to indicate a failure to go around when the aircraft was still airborne 2500+ feet down the wet runway, not necessarily a fault of the Canadians.
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The touchdown zone is generally defined as the first 3000 feet of the runway or the first 1/3 of the runway, whichever is shorter. Runway 32 in Ottawa is over 10,000 feet. This aircraft's first touchdown was at 2700 feet and the second (final) touchdown was at 3037 feet.

I'm also not following the criticism of a "higher than recommended vRef" in the report. The crew calculated a vRef of 128 with a VAPP of 133 (standard). At about 1000 AGL they were told of a 10 knot gust so they upped VAPP to 140 to account for the gust. Yes, the correct number probably would have been 138, but this was at 1000 AGL. Furthermore, the aircraft crossed the threshold at 139 KIAS which is one knot above VAPP with 5 knots of gust factor.
 
Canada doesn't groove their runways do they? I'm pretty sure every runway I landed on in Canada was not grooved. YUL, YHZ, YYZ, YOW.

I remember I would always feel the anti-skid kick in and reduce braking and would have to resort to reverse thrust to get the a/c slowed when the runway was even just wet. In the US, on a grooved runway, a wet runway is almost no different than a dry one.
 
adk said:
The touchdown zone is generally defined as the first 3000 feet of the runway or the first 1/3 of the runway, whichever is shorter. Runway 32 in Ottawa is over 10,000 feet. This aircraft's first touchdown was at 2700 feet and the second (final) touchdown was at 3037 feet.

I'm also not following the criticism of a "higher than recommended vRef" in the report. The crew calculated a vRef of 128 with a VAPP of 133 (standard). At about 1000 AGL they were told of a 10 knot gust so they upped VAPP to 140 to account for the gust. Yes, the correct number probably would have been 138, but this was at 1000 AGL. Furthermore, the aircraft crossed the threshold at 139 KIAS which is one knot above VAPP with 5 knots of gust factor.
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Their ops manual has them add the full gust factor? Interesting. I can see your point about having 10,000 feet of runway, however I'm still curious why they didn't go around when wind shear had them adding full power for 7 seconds after having descended within 20' of the runway. I don't fly jets but from what little I know of their flight characteristics wouldn't it be generally considered to be a bad idea to continue a landing attempt after such a point?
I guess really the discussion of runway length is moot since they went off the side, not the end. The fact of the matter is though according to the NTSB the approach did not meet their stable approach criteria and therefore a go around should have being initiated.
 
wheelsup said:
Canada doesn't groove their runways do they? I'm pretty sure every runway I landed on in Canada was not grooved. YUL, YHZ, YYZ, YOW.

I remember I would always feel the anti-skid kick in and reduce braking and would have to resort to reverse thrust to get the a/c slowed when the runway was even just wet. In the US, on a grooved runway, a wet runway is almost no different than a dry one.
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They don't know how to paint markings either.
 
Roger Roger said:
Their ops manual has them add the full gust factor?
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I don't work for them but my Ops Manual says 1/2 the gust, minimum 5 knots gust factor added to VAPP, which is normally vRef + 5. So when I fly, a 5-10 knot gust would equal a VAPP of vRef + 10.


Roger Roger said:
I'm still curious why they didn't go around when wind shear had them adding full power for 7 seconds after having descended within 20' of the runway. I don't fly jets but from what little I know of their flight characteristics wouldn't it be generally considered to be a bad idea to continue a landing attempt after such a point?
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I agree with you here, however the report did not mention windshear but rather an illusion of increased sink rate as they entered an area of heavy precipitation. I don't want to crucify the crew but it sounds to me like an overager attempt to smooth out the landing.



Roger Roger said:
I guess really the discussion of runway length is moot since they went off the side, not the end.
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The CA opted to set the emergency brake, which disabled anti-skid. He set it after getting little to no braking from both his and the FO's pedals. My theory is that if the plane had thrust reversers or the the runway had grooves this plane would have stayed on the runway.
 
I doubt they were trying to get a squeaker by adding full thrust for 7 seconds. Perhaps it wasn't full thrust but enough to trigger a takeoff config warning? Or maybe it was a "go around" but then when they touched down anyways they tried to make a landing out of it?
 
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If they got the takeoff config warning they were already on the ground. Takeoff config isn't checked unless you have weight on wheels.
 
If there's some reason why I have to have FULL POWER in for any amount of time approaching the threshold, it's time to try the approach again. A small bump up because you think it's about to drop in is fine but FULL POWER? Broooo! And why was it still in after they touched down?

I also got a chuckle out of the request for the FO to apply max brakes.
 
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