Continental 737 Off Runway at DEN
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Looks like the LE devices were down meaning at least some degree of Flaps were deployed.
Have a look at 9NEWS.com | Colorado's Online News Leader | 9Slideshows Gallery | Continental1404
For any of you 737 drivers out there, what is the crosswind limit for the 737-500? I'm not 100% sure but with winglets (which this 500 was fitted with) decreases the Max crosswind limit.
AeroPlanner.com
How that plays into the accident, who knows.. Lets wait to see what the NTSB says... Should be interesting none the less..
Have a look at 9NEWS.com | Colorado's Online News Leader | 9Slideshows Gallery | Continental1404
For any of you 737 drivers out there, what is the crosswind limit for the 737-500? I'm not 100% sure but with winglets (which this 500 was fitted with) decreases the Max crosswind limit.
AeroPlanner.com
How that plays into the accident, who knows.. Lets wait to see what the NTSB says... Should be interesting none the less..
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The media is reporting that the airplane did takeoff for a few seconds, maybe they had an engine failure during Vr, started to just leave the ground and caught wind gust which pushed it down to the ground? 
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The fact the leading edges appear to be down in the picture, does not mean that the flaps were deployed for TakeOff.
Flying the 737 on the line, as part of the evacuation drill, we select FLAPS to assist with the evacuation.
Watch this space, think there is something more to this story,
Crew forgetting to set the flaps NOT to be ruled out yet.
HighLow
Flying the 737 on the line, as part of the evacuation drill, we select FLAPS to assist with the evacuation.
Watch this space, think there is something more to this story,
Crew forgetting to set the flaps NOT to be ruled out yet.
HighLow
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De-iced therefore didn't put flaps down at normal point.
But what is that crud on the fuselage and wings? Residue of a fire extinguishing agent, overnight frost or . . . . snow and ice not properly removed during de-icing?
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No V1
Looking at the DEN airport diagram
http://204.108.4.16/d-tpp/0813/09077AD.PDF
The aircraft was using 34R....video from a local tv station this morning shows a skid trail starting between F3 and F4 exiting to the left, crossing WC just east of Fire Station #4 and ending up just beyond. That distance, at first glance, would not be enough to attain V1 with a fully loaded 735 fueled for a decent length trip to IAH with the altitude impairment that KDEN has. If that is actually the case then flap settings/deployment may not be an issue.
Winds were reported off the left wing gusting to 32kt and the aircraft had been retrofitted with vertical wing tips. (A question I have is do these retrofit wingtips change crosswind ability on the aircraft?)
The debris field starts on the runway per reports...both turbines are at the aircraft with #1 offwing just ahead of the left wingtip and #2 still onwing but very beat up. The landing gear has been sheered off and is reported upstream in the debris field...one report said on the runway and another implied on taxiway WC. Aircraft is a writeoff with the fusealge having cracked open just aft of the wingbox.
http://204.108.4.16/d-tpp/0813/09077AD.PDF
The aircraft was using 34R....video from a local tv station this morning shows a skid trail starting between F3 and F4 exiting to the left, crossing WC just east of Fire Station #4 and ending up just beyond. That distance, at first glance, would not be enough to attain V1 with a fully loaded 735 fueled for a decent length trip to IAH with the altitude impairment that KDEN has. If that is actually the case then flap settings/deployment may not be an issue.
Winds were reported off the left wing gusting to 32kt and the aircraft had been retrofitted with vertical wing tips. (A question I have is do these retrofit wingtips change crosswind ability on the aircraft?)
The debris field starts on the runway per reports...both turbines are at the aircraft with #1 offwing just ahead of the left wingtip and #2 still onwing but very beat up. The landing gear has been sheered off and is reported upstream in the debris field...one report said on the runway and another implied on taxiway WC. Aircraft is a writeoff with the fusealge having cracked open just aft of the wingbox.
Landed in DEN 5 minutes before
We were pax on a flight that touched down at 6:10. Tower gave weather confirming the winds someone listed above - 220 @ 20 gusting high 30s.
For the main rways 35 L/R and 34 L/R that's a quartering tailwind.
The weather was mostly clear but there were obvious ice patches on the taxiways as we taxied in about 90 minutes after local sunset.
We were not aware that anything had happened until we left the airport by cab 25 minutes later and saw emergency equipment lights rolling on access roads and taxiways.
We were a United flight, so I was following the cockpit communications during approach on the cabin audio (ch. 9), and at least one other Frontier flight ahead of us requested rway 26 because "the winds are over our limits" for X-wind landing.
OTOH we had a smooth touchdown (757) on 35L a mile east of the accident rway and there was a Saab turboprop on a parallel approach with us to 35R that also landed OK at the same time.
Reports here all seem to point to a starboard engine/wing fire or explosion AFTER the plane had already veered and/or dropped, so it sounds like it may have been an aftereffect rather than the cause - but clearly it is way too early to rule much in or out.
Does sound like an inopportune wind gust will be one of several suspects.
Reports say the craft had traveled 2000 feet down the rway (corresponds to the diagram and analysis above) - would a 737 at 5,400 feet elev. have reached Vr and rotated in that distance? Seems short. OTOH a low speed would account for the relatively low number of casualties.
For the main rways 35 L/R and 34 L/R that's a quartering tailwind.
The weather was mostly clear but there were obvious ice patches on the taxiways as we taxied in about 90 minutes after local sunset.
We were not aware that anything had happened until we left the airport by cab 25 minutes later and saw emergency equipment lights rolling on access roads and taxiways.
We were a United flight, so I was following the cockpit communications during approach on the cabin audio (ch. 9), and at least one other Frontier flight ahead of us requested rway 26 because "the winds are over our limits" for X-wind landing.
OTOH we had a smooth touchdown (757) on 35L a mile east of the accident rway and there was a Saab turboprop on a parallel approach with us to 35R that also landed OK at the same time.
Reports here all seem to point to a starboard engine/wing fire or explosion AFTER the plane had already veered and/or dropped, so it sounds like it may have been an aftereffect rather than the cause - but clearly it is way too early to rule much in or out.
Does sound like an inopportune wind gust will be one of several suspects.
Reports say the craft had traveled 2000 feet down the rway (corresponds to the diagram and analysis above) - would a 737 at 5,400 feet elev. have reached Vr and rotated in that distance? Seems short. OTOH a low speed would account for the relatively low number of casualties.
Last edited by pattern_is_full; 21st Dec 2008 at 17:46.
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Not a Classic 737, a NG ?? ...
Girls/Guys , the a/c has winglets, so a 737-700 or greater, ie a NG, according to the 9NEWS.com | Colorado's Online News Leader | 9Slideshows Gallery | Continental1404 pix from the affiliate in DEN.
This is from a B777/A320 (ex) driver, so I stand to be corrected.
Hope the injured crew/passengers are OK, at at least in hospital with the right people looking after them.
Kiwi1
This is from a B777/A320 (ex) driver, so I stand to be corrected.
Hope the injured crew/passengers are OK, at at least in hospital with the right people looking after them.
Kiwi1
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its a classic
CO says it is a classic 735....they are retrofitting them with winglets....it has confused a lot of folks but it is a 735. 
Here is their statement
Continental Airlines Responds to Flight 1404 Accident: Financial News - Yahoo! Finance
HOUSTON, Dec. 21 /PRNewswire-FirstCall/ Continental Airlines (NYSE: CAL - News) tonight confirmed that flight 1404, a Boeing 737-500 aircraft carrying 110 customers and five crew members, went off the runway at Denver International Airport following a scheduled 6 p.m. MST departure to Houston Bush Intercontinental Airport
snip....
Here is their statement
Continental Airlines Responds to Flight 1404 Accident: Financial News - Yahoo! Finance
HOUSTON, Dec. 21 /PRNewswire-FirstCall/ Continental Airlines (NYSE: CAL - News) tonight confirmed that flight 1404, a Boeing 737-500 aircraft carrying 110 customers and five crew members, went off the runway at Denver International Airport following a scheduled 6 p.m. MST departure to Houston Bush Intercontinental Airport
snip....
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No it's a 500 all right (winglets retrofitted an increasingly common mod to save a bit of gas)
Older guys (300/400/500) had pitot probes under FD no 2 window where they would catch your b@lls during evacuation, the NG moved them forward to a more pilot friendly location.
Taxying behind it, the NG is the female version ( two holes below the fin for APU) the Classic is only blessed with one.
There you go simple guide to 737 model recognition.
Older guys (300/400/500) had pitot probes under FD no 2 window where they would catch your b@lls during evacuation, the NG moved them forward to a more pilot friendly location.
Taxying behind it, the NG is the female version ( two holes below the fin for APU) the Classic is only blessed with one.
There you go simple guide to 737 model recognition.
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that's why?
They moved them...to save Pilot's privates??? Dang...all this time I thought it was because the jetway jockeys kept smashing them....the sensors I mean...grin
737 drivers (or equivalents): What are the dynamics of a twin-jet during acceleration in the early part of a TO roll?
I know the Guppies have a honking big rudder, but how does its effectiveness build up as speed increases? Is there a vulnerable point to a gust at moderate speeds (40-70kts) where the wing is starting to develop some lift and reduce tire contact ("light on its wheels") but not enough airflow for the rudder to be fully effective?
I'd guess if there is, then that is calculated in in certifying the X-wind limits, but that an overlimit gust at just that moment could make for a bad day.
I know the Guppies have a honking big rudder, but how does its effectiveness build up as speed increases? Is there a vulnerable point to a gust at moderate speeds (40-70kts) where the wing is starting to develop some lift and reduce tire contact ("light on its wheels") but not enough airflow for the rudder to be fully effective?
I'd guess if there is, then that is calculated in in certifying the X-wind limits, but that an overlimit gust at just that moment could make for a bad day.
Highlow;
Some observations and a question..
Extension of the slats alone would bring the stall speed down significantly. While the flaps can't be seen in the available photos, the fact that the slats are extended perhaps lends credence to correct extension of the flaps even given your helpful comment re evac procedures and extension of flaps, an interesting if not unfamiliar procedure, and my question is at what point in the Passenger Evacuation Checklist (QRH) is that checked/done and what setting is used? Additional question...are there any WAT circumstances in which a slats-only takeoff is made? - I ask because on the DC9, slats-only takeoffs were employed at high gross weights, (which this flight would certainly not have been). Just curious - not suggesting anything. The recorders will be in good shape.
We can see that the wind, as posted above anyway, was from the aircraft's left (west) side with a crosswind component of between 13kts, (sin50deg x 18kts) to (sin50deg x 38kts) 24kts on the gusts yet, (not particularly significant or unusual in and of itself), from the photos thus far available, the aircraft appears off the west side of 34R. No overhead photos seem to be available to confirm the site. One report stated that the aircraft was near WC when it departed the runway environment. WC is about 3800+ft from the threshold of 34R. I should think a typical takeoff run would be in the neighbourhood of 4500ft given WAT conditions and headwind.
The fact the leading edges appear to be down in the picture, does not mean that the flaps were deployed for TakeOff.
Extension of the slats alone would bring the stall speed down significantly. While the flaps can't be seen in the available photos, the fact that the slats are extended perhaps lends credence to correct extension of the flaps even given your helpful comment re evac procedures and extension of flaps, an interesting if not unfamiliar procedure, and my question is at what point in the Passenger Evacuation Checklist (QRH) is that checked/done and what setting is used? Additional question...are there any WAT circumstances in which a slats-only takeoff is made? - I ask because on the DC9, slats-only takeoffs were employed at high gross weights, (which this flight would certainly not have been). Just curious - not suggesting anything. The recorders will be in good shape.
We can see that the wind, as posted above anyway, was from the aircraft's left (west) side with a crosswind component of between 13kts, (sin50deg x 18kts) to (sin50deg x 38kts) 24kts on the gusts yet, (not particularly significant or unusual in and of itself), from the photos thus far available, the aircraft appears off the west side of 34R. No overhead photos seem to be available to confirm the site. One report stated that the aircraft was near WC when it departed the runway environment. WC is about 3800+ft from the threshold of 34R. I should think a typical takeoff run would be in the neighbourhood of 4500ft given WAT conditions and headwind.
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Am I imagining things, or do the photos we have so far show a rip around the circumference of the fuselage aft of the wings, wider at the top than on the sides? Makes me think the tail section of the plane almost came off. Would mean some pretty powerful downward force, no?
@Mark: Yep, big ol' crack. In the News9 slide show linked to on this thread above, the first slide shows the plane skipped over a ridge or dam across the ravine, topped by an access road (too skinny to be a taxiway/runway) - likely the one marked WC on the airport diagram. That thump (or the flop after it) probably cracked the hull and took the left engine off.
Airport officials who've been on the scene report the plane veered off the RIGHT side of the runway, BTW. That skinny ridge-top road I mentioned above, that is about 150 feet behind the tail, is not the runway.
But it's early, so I'm open to being corrected (or correcting myself) if I see better imagery.
Airport officials who've been on the scene report the plane veered off the RIGHT side of the runway, BTW. That skinny ridge-top road I mentioned above, that is about 150 feet behind the tail, is not the runway.
But it's early, so I'm open to being corrected (or correcting myself) if I see better imagery.
Mark in CA;
Yes, it is a crack. No it does not necessarily mean "downward" - the crack extends from the right side of the fuselage, across the top but does not appear on the left side of the fuselage. I don't know the 737 but that may be a joint where the rear fuselage section joins the over-wing section. That would be more consistent with stronger lateral forces than vertical forces although rough terrain will present a complex mixture of such forces, of course.
Note that the track of the aircraft curves very slightly left, and that the heading of the aircraft is pointing slightly left (about 10 to 15 degrees) of the track taken.
Would mean some pretty powerful downward force, no?
Note that the track of the aircraft curves very slightly left, and that the heading of the aircraft is pointing slightly left (about 10 to 15 degrees) of the track taken.
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originally posed by kiwi1:
Girls/Guys , the a/c has winglets, so a 737-700 or greater, ie a NG, according to the 9NEWS.com | Colorado's Online News Leader | 9Slideshows Gallery | Continental1404 pix from the affiliate in DEN.
This is from a B777/A320 (ex) driver, so I stand to be corrected.
Girls/Guys , the a/c has winglets, so a 737-700 or greater, ie a NG, according to the 9NEWS.com | Colorado's Online News Leader | 9Slideshows Gallery | Continental1404 pix from the affiliate in DEN.
This is from a B777/A320 (ex) driver, so I stand to be corrected.
This is from a CO employee - me. Our classic 737's are retrofitted with winglets, as well as our NG 737 fleet.
pattern is full;
Yes, knew that, it's just a service road.
Yes, it probably was the "right" side - looking south! The frame of reference needs to be enlarged from someone's "handedness" to a north-east-west-south grid! 
Seriously...a right side departure doesn't correlate with the photos.
The shadows of the aircraft and service road taken as they are in morning sun, show that the aircraft maintained a northwesterly track as it left the runway. A left (west) side departure fits the available photographs. Going off the right side of 34R would mean that the aircraft "reversed course" to maintain the relationship it has with the service road - not possible! Take a look at the angle between the aircraft track and the service roads in the following diagram to see why:
That skinny ridge-top road I mentioned above, that is about 150 feet behind the tail, is not the runway.
Airport officials who've been on the scene report the plane veered off the RIGHT side of the runway, BTW.
Seriously...a right side departure doesn't correlate with the photos.
The shadows of the aircraft and service road taken as they are in morning sun, show that the aircraft maintained a northwesterly track as it left the runway. A left (west) side departure fits the available photographs. Going off the right side of 34R would mean that the aircraft "reversed course" to maintain the relationship it has with the service road - not possible! Take a look at the angle between the aircraft track and the service roads in the following diagram to see why:
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Conti Checklists on the 737 call for a Flap check several times, also on "Before Takeoff", they also have a Takeoff Config Warning Switch incorporated on all 737's. They have some of the best procedures on the 737 i have ever seen, contribution to flight safety due to training and standards is very high at CAL - i wonder what happened there... 
hbiwe;
I couldn't agree with you more strongly. We've had some excellent contact with your safety people - a great safety and operational culture, a full embracing of FOQA and ASAP programs - yes, it will be interesting to know what happened.
From an aerial video sequence, it appears that the a/c left the runway well before taxiway WC:
They have some of the best procedures on the 737 i have ever seen, contribution to flight safety due to training and standards is very high at CAL
From an aerial video sequence, it appears that the a/c left the runway well before taxiway WC:
Last edited by PJ2; 21st Dec 2008 at 20:40.