Airplane slides off runway at Chicago's Midway Airport

[Zeond]

CNN Article

Boy killed after plane skids off runway

CHICAGO, Illinois (CNN) -- A Southwest Airlines jet slid off the runway during a heavy snowstorm at Chicago's Midway Airport and crashed into at least one vehicle in a nearby intersection, killing a young boy, on Thursday night.

Flight 1248, which was arriving from Baltimore, Maryland, slid through a fence separating the runway from the intersection, said Wendy Abrams, a spokeswoman for Chicago's Department of Aviation.

The boy, who was about 8, was with his two younger brothers -- including an infant -- and his parents, said Deborah Song, a spokeswoman for Advocate Christ Medical Center in Oaklawn, where the family was transported.

The mother and father were in serious condition, Song said, and the middle son, about 3 years old, was in fair condition. There was no information on the infant.

"We're not sure if they came from one vehicle or multiple vehicles that were struck," she said.

Chicago Fire Department Commissioner Cortez Trotter said he hadn't spoken to hospital officials, but to his knowledge, there were 12 people taken to area hospitals.

Five were in serious condition -- one of those critical -- and four were in serious but stable condition, he said. Also, three people on the plane suffered minor injuries and were taken to the hospital.

There was no definitive cause given for the accident, but Federal Aviation Administration spokeswoman Laura Brown said the plane's nose gear collapsed. (Watch footage from the scene -- 1:33)

Amanda Doherty lives near the airport and said she went to the scene shortly after the crash and saw a car pinned under the airplane with its headlights still on. (Watch witness account -- :27)

A bartender at a pub down the street from the accident said he heard two loud booms when the plane crashed into the intersection.

"We thought it was an automobile accident and we looked out the window and we saw the tail section of a Southwest airliner laying across the street, on Central Avenue," said Tom Fitzgerald, adding that he saw passengers exiting the rear of the plane. "People were running and ambulances were coming down the street."

The Boeing 737 was carrying 98 passengers and five crew members. It left Baltimore-Washington International Airport about 5 p.m. ET and landed shortly after 8 p.m. ET.

Stanley Den, who was on the plane, said he noticed the plane wasn't slowing down during the landing.

"I couldn't really tell if we were on the runway or the grass. It was really bumpy," Den said. "We were kind of going for a while until the impact when we hit, maybe I guess, a barrier fence, went through that and into the middle of the street with cars and stuff riding past us."

It had been snowing all day in Chicago and visibility was poor at the time of the landing. The National Weather Service had issued a heavy snow warning in the city and surrounding area, saying that 6 to 9 inches of new snow could accumulate before midnight -- at a rate of 2 inches per hour.

There were approximately 8 inches of snow on the ground by early evening, and winds were blowing at between 13 mph and 18 mph.

Video from the scene showed at least 10 ambulances at the scene and dozens of fire trucks and other emergency vehicles converging on the intersection. The plane's fuselage was bent and its nose was on the ground.

Midway, which lies in a dense residential and commercial district of the city, west of downtown, was closed almost immediately and was not set to reopen until early Friday morning, the FAA said.

The National Transportation Safety Board was investigating the crash.

Thankfully only one fatality, sadly an 8 year old boy. From the reports on TV the snow was really bad at the time.

[Darth Mall]

Yea I heard about that, its been saturating the news here in the Chicago area.

And yes the snow has been bad. Earlier there was virtually zero visibility.

And the plows out here have been doing a shit job, but I discovered to my joy i can drive thru foot high snow banks in my car

Darth Mall

[Dartzap]

Aznyone else noticed that yet again, its been a week of aircraft related incidents? first we had that plane crash in Iran, then the man who was shot in Miami and now this?

They always come in threes!

[Broomstick]

You just know weather has to be a factor here.

At the time, there was 8 inches of snow on the ground in the vicinity of Midway. That's 20 cm for you metric folks (damn, I love that on-line converter!) All the area airports had been having problems since around 3 that afternoon. By 5, arrival delays for O'Hare were 4-5 hours and for Midway nearly 3, and the accident occured at 7, 4 hours into the storm.

Visibility was down to 3000 feet - call it a kilometer. The runway was 6500 feet, meaning if you stood at one end of the runway you wouldn't be able to see more than halfway down it. However, the runway markings at Midway are such that they inform you when you reach the halfway mark, and also when you're about to run out of pavement to allow for low visibility operations.

Midway's official weather reporting actually records a lull at 7 pm. Excerpt:

6 pm - winds east at 12 mph, snow, freezing fog
7 pm - winds east at 13 mph, light snow, mist
8 pm - winds south-southeast at 12 mph, heavy snow, freezing fog

Eyewitnesses, however, report a very heavy snow at the time of the accident, 7:15. The videos of the scene shortly after (there was at least one new crew actually at Midway at the time, doing a piece on travel delays) also record heavy snowfall. The NTSB will have access to minute-by-minute weather conditions, unlike my hourly updated link.

That level of wind shouldn't be a problem for a jet crew - hell, I fly in land in winds twice that strong on a routine basis, in a much smaller and less capable aircraft. (I do not, however, fly in low-visibility and heavy snowstorms)

The basics of what happened is that the jet touched down and didn't stop, shot off the end of the runway, through the barrier fence, and into the intersection of 55th Street and Central Avenue. It came to rest entirely off the airport property, in Central Avenue, on top of a car (impact with the car may have snapped the nosegear)

Here is a picture of Midway from the air (no, I did not take this picture):


Those buildings that surrond the airport, right up the airport property - those are houses, the classic Chicago "brick bungalo". Which gives you an idea of just how much worse this could have been. In the early 70's a similar accident happened where the airplane sheared off treetops, took the roofs off several homes, and killed some folks in their house. After that accident they upgraded the barrier fences. That seems to have mitigated this accident, as the airplane traveled much less distance past the airport boundaries. The fence almost stopped the airplane.

Apparently, the airplane was landing on one of the big diagonals, 31C. That would give the airplane a slight tailwind to deal with, meaning the same airspeed but increased groundspeed - which requires more distance and more braking power to bring the plane to a halt. Bad enough, but given the weather the runway had to be slick, which would serously reduce braking power.

Passengers said they had a hard landing (which actually IS appropirate under these conditions), their perception was that the plane, despite the usual sound of reverse thrusters, did not slow down as usual. Passengers also reported being aware of when they left the pavement - the ride becoming MUCH bumpier at that point - and certainly felt when the airplane hit the fence.

This bears some superficial resemblence to the accident in Toronto not too long ago where a jet slid off the end of a runway during a storm. In this case, however, there was no small canyon for the airplane to fall into, nor was there fire.

My guess is that a tailwind on landing combined slippery, snowy/slushy/possibly icy pavement resulted in the airplane brakes being largely useless and the airplane retaining too much speed. From what I've been able to figure out from the news/video/etc. the pilots retained directional control - they went straight down the centerline - they just couldn't slow the machine down. There just wasn't enough distance to stop. Not too much different from hitting a slick spot on a road and finding yourself unable to stop, except, of course, airplanes of this sort are a lot more bigger and more massive and do lots more damage if they hit something.

OK - why was the guy landing downwind? Well, because the tower told him to - but why would they do that, with an all-day east wind?

It's because everything was so backed up. Chicago's two airports are busy - O'Hare is arguably the world's busiest, Midway ranks 47th world-wide (it's small only in comparison to O'Hare). Weather was horrible - they just couldn't bring the planes in nearly as fast as they usually do. That means there were airplanes stacked above the skies of Chicago yesterday, at some points arriving overhead faster than they could be put on the ground. A further complication is that the airspaces for O'Hare and Midway not only abut, they overlap to some degree. In order to prevent a collision overhead, the traffic may be arranged in such a manner that planes are forced to use a less-than-ideal runway to land. Under normal conditions, meaning dry pavement, there is sufficient runway to land a 737 with a slight downwind and stop safely with room to spare. But yesterday wasn't normal conditions.

I hope this stays to just one fatality - a first for Southwest, by the way. Until last night, they had never had a fatal accident. So that distinction reverts to Qantas alone.

I also hope the guy in charge wasn't the Southwest captain who is a regular down at my home airport... I just know the guys in the front seat are going through hell right now between guilt over causing death and injury and all the investigatory shit pilots are put through post-accident.

[LadyTevar]

Thanks, Broomstick. I was guessing that the landing slip was icy or at least too slick to stop the plane, but I had no idea the runway was that close to a urban area.

[Edi]

Very informative. I figured something like that (bad weather, icy runway etc) as well, was nice to have it confirmed in such great detail. One can always count on her posts being worthwhile reading.

Edi

[The Duchess of Zeon]

The fact that anyone at all survived in a car which was struck by a passenger jet shows this accident to be an example of astonishing fortune for all involved save that one poor boy.

[Broomstick]

Duchess, I'd be more relieved if some of those in the two cars that wound up under the jet had improved from "critical". It is entirely possible we may lose more of them, although everyone is hoping for rapid improvement and complete recovery of all injured.

A mod might want to put a warning in the subject about pictures - I'd do it but I don't have the ability. (And if it's more appropriate to move to Art and Photos at this point go right ahead)


This is a picture from last night - I'm guessing around 9:30 to 10 pm local because that's when there was another lull in the storm, allowing for a relatively sharp picture:

Indisputably, the airplane is in the intersection, not on the airport property.

Another view from last night:




This gives a good view of the situation post-crash:

And another one:

You can see what might be landing gear tracks in the snow in the upper picture, and the remains of the barrier the plane smashed through as well as the airport perimeter fence - which shows that the airplane remained on-course until it was past the wall. It wasn't the crosswind throwing them off... if it had been the airplane track would not be so straight. What skewed the airplane's path was (I'm guessing) damage to the landing gear and getting two cars snagged under the airplane.

Considering this was rush hour, when the streets are bumper-to-bumper with traffic, it's surprising that only two cars were hit. Momemts before the stoplight had been red and the street was full of sitting vehicles.


From this morning:

Some of this damage looks like it might be street signs and traffic lights and not just jet engine. This, by the way, is what happens when you attempt to travel on the engine nacelle rather than the landing gear.



You have to look closely at this one - there's a car under the wing just to the right of the engine nacelle. This, if I have the facts correct, is the lesser damaged of the two cars that were hit by the airplane.




I believe this car is the one where the boy was fatally injured:

Do keep in mind some of that damage was caused by rescue crews cutting the victims out of the wreck.



Another view showing just how close this thing came to hitting houses:

[Broomstick]

And, oh yes, the airplane also demolished part of the instrument landing system that guides airplanes to the runway in low visibility. It's part of that tangle around the nose... although for the life of me I can't pick it out of the mess even though I know what the things look like... what the plane plowed through it pretty much destroyed.

[lukexcom]

The last time something like this happened with a Southwest jet, in Burbank, CA, it touched down WAY too far down the runway at 182 knots!, way above its usual Vref speed which is in the 110-120 knot range. Careened out of the airport, ending up at a gas station. A few serious injuries, but fortunately no deaths. Accident factors: pilot error due to flying a high and unstable approach and trying to rush into the airport. Some Southwest pilots can be a bit notorious for using the infamous "Southwest Airlines style" technique of get there fast, taxi to the gate fast, and do everything very very fast. I have heard of many complaints from other airlines' flight crews about how some Southwest flight crews have what they deem as a somewhat reckless attitude about handling their aircraft, flying faster than the Vref - the recommended approach speed when flying down to the runway, sometimes to the point of ATC instructing them to slow down in order to maintain proper aircraft separation distances. Last time I asked a Northwest 757 Captain (and a very good friend of mine), he didn't have the prettiest words about some of the Southwest flight crews out there.

He wrote a very fascinating article about the "Captain and F/O found naked by flight attendant in the flight deck of a Southwest ferry flight" and some other Southwest incidents.

I hope that this isn't the case here. And honestly I kind of doubt it is, due to the challenging nature of the airport and the weather factors, the crew would most likely have not been playing around. Midway Airport is a very challenging airport for 737-sized jets to operate out of. The useable runway distance available from where the ILS glideslope intercepts the runway is within 4,900 to 5,200 ft. for those runways (depending on which one). Challenging enough to plant the aircraft firmly on the ground at the right spot (not much room for a flare here for those sized aircraft) and stopping it on a calm day on a dry runway when your 737 Next Generation aircraft (-600, -700, -800, and the -900 models) landing distances can be from 2,500 ft at a low landing weight over 4,000 feet at max landing weight, among other factors.

With such heavy snow, the runway conditions must have been pretty bad. But in any case, we must await the NTSB reports as to the probable causes and contributing factors of this accident. Did the pilots land too fast? Did they touch down too far down the runway? Were the thrust reversers deployed to full power? Was there an issue with the braking system? Were spoilers also deployed? Should the crew have diverted to O'Hare and it's 10,000 ft.+ runways? Were there any other factors involved in this incident?

[Broomstick]

Accident factors: pilot error due to flying a high and unstable approach and trying to rush into the airport. Some Southwest pilots can be a bit notorious for using the infamous "Southwest Airlines style" technique of get there fast, taxi to the gate fast, and do everything very very fast. I have heard of many complaints from other airlines' flight crews about how some Southwest flight crews have what they deem as a somewhat reckless attitude about handling their aircraft, flying faster than the Vref - the recommended approach speed when flying down to the runway, sometimes to the point of ATC instructing them to slow down in order to maintain proper aircraft separation distances. Last time I asked a Northwest 757 Captain (and a very good friend of mine), he didn't have the prettiest words about some of the Southwest flight crews out there.

And yet, Southwest went 35 years without a fatal accident -- something Northwest, United, American, Delta, and the others can't claim. I take flight crews ranting about the competitors' flight crews with a grain of salt. Every company has its bad apples.

Another factor is that Southwest routinely flies 737's into smaller airports than the big hubs. That is, in fact, one of their cost-saving strategies because the smaller airports have lower fees. Getting a jet that size into and out of relatively small fields in all weather is a challenge.

In addition to the insanely small (for a 737) footprint of Midway, certain approaches require you to maintain a high altitude for safety since Chicago does have buildings over 1000 feet tall (over 300 meters). Cargo pilots, in particular, from ALL carriers bound for Midway tend to come in high and drop fast - which is a non-standard approach, makes maintaining airspeed a challenge, but is actually safer for that particular airport than the idealized 3 degree glideslope.

It's been a concern of pilots for at least 30 years about just how tightly confined Midway is.

A little history (out of memory) about Midway airport: Midway was originally a small truck farm back in the early, early 20th Century. Specifically, an onion farm. This is sort of interesting in that the name "Chicago" is probably derived from the Native word for "wild onion" (a possible alternative is "stinking swamp", but not much favored by officials for obvious reasons). Anyhow, that's how it got its dimensions - it occupies the old farm parcel. Back then, it wasn't even in the city limits and the area was small farms. The owner got interested in aviation, and as many farmers did in those days, and quite a few still do, he carved a runway out of his cropland. As time went by more and more flying went on and airplanes replaced the onions. In 1927 Midway, now part of the city of Chicago (which had grown outwards), was designated an official airport, and since that time the airport has not expanded. In 1927 the current space was more than ample, and from the 1930's through the 1950's it was, supposedly, the world's busiest airport. In the 1960's bigger jets were built, and that's when the city of Chicago built O'Hare, specifically to accomodate those bigger jets. Now, up until that point, Midway wasn't so hemmed in by housing because most folks don't want to live so close to a major air hub. But then, in the early 1970's, the airlines all pulled out of Midway and went to O'Hare, leaving a much less busy Midway to general aviation and cargo (and even a lot of the cargo moved to O'Hare). Talk emerged of eliminating Midway and putting the land to other use. Real estate people encouraged people to buy land near Midway and build homes, telling them that the airport would be gone in five years. There were plans to build a sports complex there, among other things like shopping malls and more housing. THAT's when people built right up to the airport perimeter. When I first moved to Chicago in the very early 80's there were no commercial flights out of Midway at all and I commuted between Chicago and Detroit through O'Hare, there being no other alternatives. Then, in the mid-80's, with O'Hare at capacity, someone had the bright idea of flying smaller passenger jets out of Midway. I remember this because I started flying out of Midway then, MUCH relieved at the ease of getting there and the lack of crowding (back then - that's changed. Midway is as much a zoo as O'Hare these days). Apparently, a lot of other people made the same choice. Today, Midway handles even more passengers than it did in it's prior heydey in the 1950's. So, because Midway nearly died in the mid-70's and there are greedy real estate agents we have people living an insanely short distance away from runways.

There are three ways to make Midway safer:
1) Ban big jets - but this will do Bad Things to the airport and local economy.
2) Eliminate the airport - not gonna happen, even worse than #1
3) Expand the airport - a political hot potato, because that means evicting people from their homes and seizing their property. Certainly, the city or state could do this through eminent domain with public safety as a justification. It's certainly on the table, and has been for years, but with 33 years since the last jet skidded off the airport there hasn't been the perception of danger by people outside the immediate area. Now there is - there were politicians on the local news last night making noises about Doing Something to Prevent Such Awful Tragedies.

He wrote a very fascinating article about the "Captain and F/O found naked by flight attendant in the flight deck of a Southwest ferry flight" and some other Southwest incidents.

Now, be fair - the Southwest pilots were naked, yes, but isn't Northwest the airline that's been having problems with drunken pilots the past few years? Yet I wouldn't suggest all Northwest pilots have a drinking problem, nor do I think most Southwest pilots are reckless or naked.

due to the challenging nature of the airport and the weather factors, the crew would most likely have not been playing around. Midway Airport is a very challenging airport for 737-sized jets to operate out of. The useable runway distance available from where the ILS glideslope intercepts the runway is within 4,900 to 5,200 ft. for those runways (depending on which one).

The runway involved in this accident was 31C, Midway's longest at a little over 6500 feet, which, with a standard 1,000 touchdown point, leaves 5500 feet. The ILS might well intercept the runway past the standard 1,000 feet given the local obstacles.

I can verify, as someone who has flown as a passenger through Midway many times, that the pilots frequently put the wheels down right on the edge of the pavement, as in the tail is still over grass at touchdown, in order to maximize their available runway. I have no doubt that the NTSB will be trying to verify through multiple means the approach, airspeed, and touchdown of the jet. For accident analysis purposes, it's a small blessing to have so much snow, in that the tracks of the airplane can still be seen the next morning (of course, if the snow hadn't been there at all this might not have happened) but they'll also be using the CVR and FDR, which, since there was relatively little damage to the jet, are in perfect condition. They've already pulled the plane-to-tower tapes and radar data.

CNN got ahold of some of that and had some wanker talking about it - there were some unusual speed numbers there, but they never made it clear if it was groundspeed or airpseed. It can be an important difference. But it was raw data and they weren't even sure if the numbers were miles per hour or knots! Shouldn't have been speculating about it on the TV.

With such heavy snow, the runway conditions must have been pretty bad.

They had, in fact, closed all other runways at Midway to devote all their snow moving equipment to just that one, their longest.

There's a cultural aspect to all this as well, which may not be apparent to outsiders. Chicago is NOT a city that stops for a snowstorm. Midway's official total was 10 inches/25 cm with some unofficial observations of 13 inches/33 cm of snow just a few blocks away. At the time of the accident, the snowfall was estimated to be at the rate of 3 inches/8 cm an hour. The city is trying to maintain that it's "perfectly safe" to be running an airport in those conditions. It's not - there really is a higher risk than in good weather. Just like on the road. That's a certain level of disconnect among the city officials, where they'll talk about hazardous streets and ask people to limit driving or go slower yet maintain the aviation side of things is just as safe as ever. Well, that's partly becuase that fuckwad asshat Daley knows jackshit about aviation, the same for most of his despotic regime. But it's also because both those airports are major, major economic engines in the region and shutting them down, even partially, hurts the city's pocketbook.

But even beyond the economics, Chicago has a mindset that "a little snow" is not to disrupt business. People still work and shop in horrendous weather conditions - deep snow, hurricaine force winds, artic cold, whatever, doesn't matter, the city doesn't stop until it becomes physically impossible for vehicles to move through the streets or the power grid fails or something equally catastrophic happens. And anyone who thinks this doesn't extend to the airports is only kidding themselves. There is ENORMOUS reluctance to close those airports. They'll report 8 hour delays before they close either airport. They'll cancel almost all flights, but cheerfully go in front of the TV cameras and say, with a straight face, "but the airport is still open!". It's a hazardous attitude. Airplanes aren't city busses, they can't slow down because the runway is slick, they have to maintain a certain minimum speed until they touch down. A city like Washington, DC would close their airport in such conditions as we had last Thursday, but Chicago didn't close Midway until the accident, and O'Hare never closed at all even though it, too, was affected by the same storm. Sure, O'Hare cancelled almost all flights after the accident, and had several thousand people sleep on cots in the terminal, but thank God the airport didn't have to CLOSE!

But in any case, we must await the NTSB reports as to the probable causes and contributing factors of this accident. Did the pilots land too fast? Did they touch down too far down the runway? Were the thrust reversers deployed to full power? Was there an issue with the braking system? Were spoilers also deployed? Should the crew have diverted to O'Hare and it's 10,000 ft.+ runways? Were there any other factors involved in this incident?

Absolutely. All of that must be looked into. Which is why I was annoyed at CNN pontificating one out of context set of data which might or might not have been accurate.

Not sure about the "divert to O'Hare" option though - they were in the same storm, after all. Where did the Midway traffic go after the airport closed?

Rather than O'Hare, diverting to Rockford - which was expericing much less intense weather - would make sense as Rockford does have a 10,000 foot runway and much, much less traffic even on a busy day. Gary, with a 7,000 foot runway, might have worked on a good day but their weather was as bad as Midway's. South Bend has an 8,000 foot runway and the same weather situation that was slamming Midway resulted in South Bend having much less snow than usual (the lake effect snow was blowing away from South Bend for a change and winding up over Chicago). Under the circumstances, diverting to either Rockford or South Bend would make more sense than going to an already overloaded and very snowy O'Hare.

[Broomstick]

Couple more items and then I might retire from this thread. This is a normal approach to Midway, as seen from a nearby street.

It's actually alarming, even though routine, to see planes that low over homes. It's not too comforting a view from inside the airplane, either - you think you're going to be knocking shingles off the roofs.


From the Chicago Sun-Times:

The Southwest Airlines jet burst through a barrier at about 46 mph and into traffic, striking cars in an incident that injured at least 10 people and killed a 6-year-old boy, Joshua Woods of Leroy, Ind....snip....

Midway lacks the 1,000-foot margin at the end of the runway that the federal government considers adequate for safety. The runway is 6,500 feet long, compared with 8,800 feet at Dallas' Love Field and 5,800 feet at Burbank, Calif., all airports used by Southwest.

If I recall, Burbank is where a Southwest jet ran off a runway, busted through a barrier/perimeter fence, crossed a street, and wound up with its nose in the middle of a gas station. So this problem is not unique to Midway. Furthermore, the Burbank incident happened in good weather on a dry runway. It was ruled to be entirely pilot error - they landed at too high a speed and couldn't stop in time.

Mayor Daley called Midway "very safe, very efficient'' and noted that the Federal Aviation Administration has deemed Midway large enough. Nearly 300 U.S. commercial airports lack the 1,000-foot margin, though a new federal law will force airports to comply by 2015.

I find it entirely fucking amusing that Dictator Daely is discussing aviation in any way, shapre or form. I'd let ya'll know how I really feel about Dick Daley, except it would detract from the rest of this thread. Suffice to say that a properly expressed rant on my part would make my recent tirade against PainRack look pretty limp and lifeless. Most pilots feel Daley should be banned from air travel of any sort (including air ambulance, should he ever need such) for life. There has been all sorts of colorful and inventive suggestions for other things to do to him, but in the US some of those suggestions, if published in a public forum, could be construed as threats and in Daley's kingdom one does not threaten the King.

Just before Flight 1248 from Baltimore touched down at Midway about 7:15 p.m., its speed was 143 mph [230 km per hour]-- . Once on the ground, its speed increased to 152 mph [245 km per hour].

And that's very interesting isn't it? It sped up after touchdown. That's VERY strange, isn't it?

Not really - a 9 mph or more tailwind acting on an airplane on a slick, that is, low friction, runway could very well do that. Winds were reported as 13 mph gusting possibly as high as 20. Hmm.... close enough. And, if true, and illustration of why downwind landings are not usually a good thing. The flight data recorder will be key here. If it shows that the pilots kept the throttles back, used de-acceleration procedures, and the plane STILL sped up on landing it skews the verdict towards "weather".

It skidded off the end of the runway and across a grassy area before -- at about 46 mph [74 km per hour] it slammed through a barrier and into the street. The plane hit one vehicle and pinned another beneath it.

It's amazing how much damage a large object moving as slow as 46 mph can do, isn't it?

Erin O'Donnell, deputy city aviation commissioner in charge of Midway Airport, said that before the accident, officials had closed all but one runway -- 31 Center -- to concentrate snow removal efforts. The runway was being plowed continuously, and there was one-sixteenth of an inch of snow when the accident occurred, which is an acceptable landing condition, said Patrick Harney, acting commissioner of the city's Aviation Department.

I've also heard that 1/16 is unacceptable. I suspect that it depends - 1/16 of preciptitation that allows traction is different than 1/16 of an inch that doesn't.

O'Donnell described the runway, in terms of its braking conditions, as "good." Later, in an evening press conference, Conners said air traffic controllers reported runway braking was fair on most of the runway but poor at the end.

Sounds like either conditions were changing rapidly, or folks are covering their asses on that one.

Earlier, Daley defended snow-removal efforts. "Midway Airport is accustomed to handling takeoffs and landings during snowstorms,'' said Daley

Here we go with that "Chicago never stops for snow" attitude.... Sure, light snow is one thing. Hell, even I fly in flurries. But there are different levels of snow storm. Driving a car was hazardous on Thursday night. This wasn't lightweight weather.

Harney said he knew of no complaints from pilots about the length of Midway's runways.

I could give him a dozen phone numbers - LOTS of pilots bitch about runway lengths at Midway. At least off the record. There's a lot of pressure not to bitch on record, for the usual reasons.

Fact is, 737's and 757's are pretty much the maximum size airplanes that can land at Midway. It's near the lower size limit for those aircraft. Add to that the close proximity of residential neighborhoods and this is NOT an easy airport to get into and out of. Further complicating the issue is the fact that if you do have a problem on departure or arrival there is literally no place to go, no relatively unused patch of ground to try for - even for the small airplanes I fly. No matter what size airplane you fly, if you have a problem going into or out of Midway you'll be landing on top of someone's house or car. In the mid-70's that was used as an argument to get rid of the airport back when it was folks in little 2 and 4 seaters dominating the place -- yet, somehow, flying much larger and potentially much more hazardous jets in and out of the place is perfectly OK and safe.

Don't get me wrong - airplanes can and are flown into and out of that airport safely every day. It is not inherently hugely more hazardous than other airports. But if an accident does occur the potential for a mass disaster is much higher. There are risks at Midway that aren't nearly so common as at other airports. Those risks are managable... but you have to manage with the thought in mind that the margin for error really is smaller than many other places and, with that in mind, perhaps that airport should close in weather like we had Thursday.

The Woods' car was crushed under the plane's wing. Three people were in a 1995 Chevrolet Cavalier that was also hit by the plane.

Alright, with those car pictures earlier in the thread - apparently I got the two backwards. The car under the wing is the one the kid and his family were in, and the one between the airplane and the lightpole the one with less serious injuries.

Rep. Jesse Jackson (D-Ill.), who has supported building a third airport, suggested in a letter to the National Transportation Safety Board that Midway is overtaxed.

He noted that the airport opened in 1927 and said "it is no larger today than it was in 1927 even though the size and speed of airplanes have increased dramatically.''

In the letter, Jackson asked, "How many operations over the original plan and design does Midway Airport currently handle?" and, "Did constraints within the local air space have any impact or causal effect with respect to the accident?''

You know, I'm not a big fan of the Jackson family, but he raises some good points here. And asks some good questions. Unlike some other Chicago politicians.

Daley, while expressing condolences to the Woods family, said the airport has been an economic boom to the city's Southwest Side.

Ka-ching, ka-ching! The only reason Daley gives a damn about Midway is the tax revenue it generates.

A little bit of history:

In the 1950s, Midway held the title of world's busiest airport. But by 1961, O'Hare had claimed that title. By the 1970s, Midway was a veritable ghost town, although it later regained popularity with Midway Airlines, then Southwest and ATA. A $927 million renovation project was completed last year, and the airport now serves more than 18 million people a year.

"The airport was closed for many years. Many people were laid off, lost their jobs. This is one of the most successful airports ... in the country,'' said Daley.

Ka-ching, ka-ching! Of course, the three flights schools - one of which had been at the airport since the 1920's - he ran off the property don't fucking matter, being small businesses beneath his contempt. After he raped Meigs field he didn't want the Coast Guard search and rescue copter based at Midway because he felt it was somehow "unsafe" - so it's in Muskegon, Michigan now and if someone fucking drowns in Lake Michigan that's just too fucking bad - we can always find new tourists and/or breed new citizens, right? And somehow it's always Daley counsins or close friends who get the contracts for construction or services at Midway...

While a 1972 crash near there killed 45, accidents at Midway have been rare. In April 2002, a jet lost a piece of fuselage, which bounced off the top of a house but injured no one. In September 2003, a jet overshot a runway and crashed into a barrier wall. No one was injured.

Yep, shit drops off airplanes a lot more often than people want to know about - happens over by O'Hare, too. It's an inherent hazard of using air travel, though of course everyone involved tries to minimize the number of bits falling off. Likewise, airplanes do run off runways, although it usually doesn't make the news big time because usually it's a minor thing with no hurt and little if any damage. If you're at an airport and see three parallel gouges in the ground next to a runway or taxiway... well, someone goofed.

Thursday's death was the first accident-related fatality in the 34-year history of Southwest, the world's biggest low-fare airline. U.S. airline passengers are in the safest period in aviation history, with a three-year accident rate of one per 15 million flights, the FAA said last month.

It's a damn shame Southwest's no-fatality record has been broken... but 34 years of such is quite a testament to the airline's safety.

[Broomstick]

From the Chicago Tribune, with quotes from Mr. Woods, father of the family that wound up under the airplane:

Joshua Woods and his brothers were in the back seat of the family's new car, eating chicken strips on the way to their grandmother's house.

While heavy snow swirled outside, Joshua, 6, broke into a rock-and-roll chorus of "Santa Claus Is Coming to Town."

Relatives and a lawyer say that as the Woodses approached Midway Airport Thursday evening and heard the roar of jet engines, the boys grew even more excited. They hoped to see a plane take off overhead.

Leroy Woods, the boys' father, had intended to drive up Cicero Avenue, but the snowstorm had snarled traffic so badly that he steered over to Central Avenue, hoping it would move faster. It didn't.

As traffic crawled and he listened to the jets, he thought one sounded too loud, and kept getting louder. He looked out a window and straight into the engine of a 737.

Southwest Airlines Flight 1248 had skidded through the end of its runway and crashed through a steel wall. It crushed the Woodses' car.

Joshua died in the crash, and his parents and two of his brothers were injured. Another brother was not in the car.

Leroy Woods remained hospitalized late Friday.

Battered and distraught, the Indiana family grieved in private Friday.

"As you can imagine, the loss of your little child is devastating, especially in an accident so bizarre," said attorney Ronald Stearney Jr., who with his father is representing the family.

After the plane hit the car, Leroy Woods immediately tried to save his boys, said Ronald Stearney Sr.

He was yelling for Joshua, and shouting, "I can't see him," Stearney Sr. said Friday.

Woods then climbed out through the shattered driver's side window. As the jet engine continued to roar overhead, Woods reached through the rear window and grabbed 4-year-old Jake and pulled him free, the lawyer said.

Joshua and Matt, 1, had to be extricated with machinery, Stearney Sr. said.

In all, at least 10 people were injured in the crash, including minor injuries to three of the 98 passengers on the airplane.

A second car carrying four people appeared to have run into the plane as it skidded into the street, fire officials said. Those four were taken to hospitals, but their injuries did not appear to be serious, Fire Department spokesman Larry Langford said.

Relatives and the lawyers described the Woodses as a family that never had it easy but were looking forward to better times and a bright Christmas.

Joshua was a kindergartner at Winfield Elementary School, about a mile outside Leroy, a tiny town in northwest Indiana where the family moved this year. School officials were heartbroken about the news of the sweet-faced boy's death.

Lisa Woods called Joshua's school Friday morning to tell the principal about her son.

"It wasn't a long conversation," Principal Patricia Carnahan said. "It wasn't a detailed conversation. It was just a sharing of tears and hugs through the phone. And letting her know how hurt we were along with her."

[Broomstick]

Norwest Indiana Post-Tribune:

CHICAGO — It started out a joyful trip. Six-year-old Joshua Woods was singing Christmas songs when he and his family turned to watch the plane land beyond the gates at Midway Airport, some 60 miles from their Leroy home.

Then, suddenly, a deafening roar arose and the family watched in horror as the jetliner crashed through the fence onto Central Avenue and headed toward them.

A panicked attempt to avoid the careening plane instead carried the Leroy family’s Pontiac Bonneville into a utility pole and into the path of the 737.

Joshua died from injuries he suffered when the Southwest Airlines jetliner crushed the family’s car Thursday night as they drove to visit grandparents.

The Woods family had moved to Leroy only this year, but Joshua and his three brothers — Joey, Jacob and Matt — already were a familiar sight to neighbors.

“The kids would always ride bikes, and they all had this screaming blond hair,” said Gale Reynolds, who lives down the block from the Woods’ modest frame house.

“This is a real shock. It hits very close to home,” Reynolds said, shaking his head while his sons played in the snow nearby.

According to an official with knowledge of the crash, the car had slowed so the family could watch the flight touch down.

The car, carrying all the Woods except Joey, who was with grandparents, tried to pull away from the skidding flight, but hit the pole and could not get away in time.

The boy and his family came to Leroy from Lowell about 10 months ago, according to Terry West and Monica Taylor, who live near the Woods with their five children on Elkhart Place.

The Woods moved to town to get a new start after Joshua’s father, Leroy, got hurt and lost his job at a steel mill, West said.

Leroy Woods recently received a settlement check because of his injury, and things were improving for the family, according to West.

“Everything was just starting to come together for them,” West said. “Things had been rough lately and were finally starting to look up, and then this.”

Leroy Woods had purchased the Pontiac about a week before the crash, West said.

Friday evening, Leroy Woods remained hospitalized at Advocate Christ Medical Center in Oak Lawn, Ill., the same hospital where his son was declared dead on arrival after they were pinned inside the car.

Hospital officials declined to give an update on Leroy’s condition at the behest of the family.

Matt and Jacob were treated at the hospital for minor injuries as was their mother, Lisa.

Steve Peters, Joshua’s uncle, came to Leroy to get clothing and other necessities for the family so they could stay with relatives closer to Oak Lawn.

“I’m still at a loss for words,” Peters said as he got in his car outside the Elkhart Place house. “I haven’t accepted the fact that this happened.”

“Joshua was a beautiful child, just like all 6-year-olds. He was an average kid.”

At Winfield Elementary School, where Joshua was a kindergartner, Principal Patricia Carnahan was trying to cope with waves of emotion as the full impact of the crash became apparent to the boy’s fellow students.

“When we saw this last night, coverage of the crash, our hearts broke because we knew there were injuries,” Carnahan said. “But this morning, we learned this tragedy touched our school family, and it became so much more tragic for us.”

Joshua’s mother called the school Friday morning to tell Carnahan what had happened.

“It just speaks so well of the family, that they thought to get in touch with us as quickly as they did to let us know,” the principal said.

During morning announcements, Carnahan spoke to the students about what had happened.

As Joshua’s classmates got into their cars with their parents Friday, they grappled with the news.

“That boy, he was in our school,” one child told his father while hurrying through the cold morning to his car.

A girl pulled her head off her father’s chest to face him as he carried her. “He got hurt really bad, and he died,” she said.

[Broomstick]

And I think that's about it - I saw a video on CNN of them moving the airplane today - it was quite impressive. They've been off-loading cargo and baggage since Friday, to lighten the load. Today, the used a BIG crane to lift the front half of the airplane onto a truck - it reminded me of one of the steel-hauling trucks they use at the area steel mills to transport tons of metal. I wonder where they got the crane, have to wonder what construction site loaned it to them. Quite impressive, but I can't locate an on-line picture - if someone else can by all means at it to the end of this thread.

An empty Boeing 737-700 weights 38,147kg (84,100lb). It requires a large tow truck.

[lukexcom]

Well, more media coverage into the rumor mill. MSNBC (originally AP)reports that the crew stated that ... (a snippet of the article) :

CHICAGO - The reverse thrusters that should have slowed a Southwest Airlines jetliner before it slid off a runway at Midway Airport and into the street didn’t immediately kick in when the pilots tried to deploy them, federal investigators said Saturday after interviewing the crew.

How much of a role that braking equipment played in Thursday’s deadly accident wasn’t immediately clear, though, and the investigation is continuing.

The plane’s flight attendants told investigators that the Boeing 737 didn’t appear to slow after it touched down at Midway in a snowstorm Thursday, said Robert Benzon, the National Transportation Safety Board’s investigator in charge.

“They all said it was a smooth landing but they could sense a lack of deceleration,” Benzon said.

He said the pilots told investigators they began applying the brakes manually as soon as they noticed that the plane wasn’t slowing properly. The plane, with 98 passengers aboard, slid through a fence and into street traffic, where it killed a six-year-old boy in a car.

Because of the blowing snow, none of the air traffic controllers actually saw the plane land, but more than 10 cameras have been identified that could provide additional information, including details about the runway conditions, Benzon said.

On Saturday, workers used a crane with a sling to lift the damaged airliner off the city street and into a hangar for further inspections.

Southwest said the captain piloting Thursday’s flight has been with the airline for more than 10 years, and the first officer has flown with Southwest for 2½ years. It was the first fatal crash in the airline’s 35-year history.

Full article available here

Interesting, Associated Press/MSNBC claims that the pilots stated that the thrust reversers didn't initially deploy properly, and thus had to revert to "manual braking", and the flight attendants reported "it was a smooth landing but they could sense a lack of deceleration".

Now, I'm going to throw some aircraft performance numbers out here: A Boeing 737-700, supposedly the model that crashed at Midway, has the following landing distance variables from its AFM:

At a 1,000 ft. Pressure Altitude (usually aroud 3-5% landing distance difference per 1,000 ft. Pressure Altitude difference, for the first few thousand feet), "wet" runway conditions, assuming max reverse thrust and max wheel braking application, zero wind tails. The flight was from Baltimore-Washington, so it's landing weight should fall somewhere within these landing distance figures...

minimum runway distance required - at this specified landing weight:
4200 ft. - 85,000 lbs.
4600 ft. - 96,400 lbs.
5000 ft. - 108,000 lbs.
5400 ft. - 119,700 lbs.

Now, take those results, and correct for an assumed 10 knot tailwind, and we get the following modified runway distances required at the same landing weights. Landing weights still remain the same as computed above...

Original runway distance required in previous table- runway distance required with 10 kt. tailwind:
4200 ft. - 4450 ft.
4600 ft. - 4860 ft.
5000 ft. - 5270 ft.
5400 ft. - 5680 ft.

Autobrakes settings (the automatic wheel braking systems that activate on wheel touchdown, when preset to one of these levels during the descent/landing checklists), on a DRY runway:
Setting 1: 4 ft./s^2
Setting 2: 5 ft./s^2
Setting 3: 6 ft./s^2
Setting 4: 7.5 ft./s^2
Max Auto: 11 ft./s^2

The AFM notes that it is beneficial that lift spoilers and reverse thrust is applied, to reduce the pressure, wear and tear to the wheel breaking system, thus preventing severe damage or overheating issues to the wheel breaking system if it's used by itself. The settings listed above will be the target settings that the system will strive to maintain regardless of whether or not the reverse thrusters and lift spoilers are used or not.

Now, one last crucial piece of information. Numbers like these are usually derived with the following criteria:
-brand new, out-of-the-factory test aircraft
-highly skilled test pilot
-controlled conditions, usually with as few variables being changed per flight as possible

All pilots are trained to account for those facts when computing various flight variables for their aircraft. This is especially evident at the Private Pilot level, with differences from the "by-the-book" numbers to one's assumed actual aircraft performance (your flight skills factor in significantly on these calculations, among other things) during the flight planning process, is as much as 20-50% difference on the conservative side, for one's own safety. At the Commerical Pilot and Airline Transport Pilot levels, these differences are FAR smaller to the point of being almost negligible in some calculations during flight planning (due to high precision performance, parts, maintenance, training, etc), but nevertheless the differences may still be there. And pilots are trained to be aware of that, plus the fact that there are many other variables that may affect the performance tables.

Now, if the runway still had "good" or "fair" braking conditions, as some news sources claim that previous landing aircraft and ATC claim, then a thrust reverser anomaly or malfunction could have possibly contributed to the accident....but, like I said, we should let the NTSB determine the probable causes and contributing factors to the incident, no matter how long it takes. In the mean time, the best we can do by discussing this accident and the media's reports on it is by speculating on how an accident like this could be influenced by various factors like the ones mentioned by the media, so long as we understand that those are only speculations at best, and that we must let the NTSB do their work and not jump to any conclusions in the mean time.

Broomstick, I am very impressed by your contributions to this thread and other aviation topics, especially your "Airport Stories". I am glad to share the skies with those who have the aviators' common-sense like you. May your landings be soft and crosswind-free.

[Broomstick]

CHICAGO - The reverse thrusters that should have slowed a Southwest Airlines jetliner before it slid off a runway at Midway Airport and into the street didn’t immediately kick in when the pilots tried to deploy them, federal investigators said Saturday after interviewing the crew.

Well, that can certainly cause a problem!

The plane’s flight attendants told investigators that the Boeing 737 didn’t appear to slow after it touched down at Midway in a snowstorm Thursday, said Robert Benzon, the National Transportation Safety Board’s investigator in charge.

“They all said it was a smooth landing but they could sense a lack of deceleration,” Benzon said.

It's interesting that everybody is saying that, and at least some of the equipment concurs. Wonder if this was actually a mechanical failure in part or whole?

Because of the blowing snow, none of the air traffic controllers actually saw the plane land

Yet more indication that the weather was bad.

At a 1,000 ft. Pressure Altitude (usually aroud 3-5% landing distance difference per 1,000 ft. Pressure Altitude difference, for the first few thousand feet)

You may wish to revisit your altitude assumption - Midway is at 620 MSL. I couldn't retrieve pressure altitude for the time in question, but let's assume it's the standard 29.92 (probably wasn't, but gotta plug something in) at a temperature of 22F/-5C (I remember checking the temp before I headed home) that yields a density altitude of -1,701. Now, I'm no expert on the big jets, but would the density altitude being that low affect the runway distance, meaning that the required distance would be a little shorter than what you posted? Seems to me it would, but given how early it is and that I haven't had my morning caffeine yet I could be a bit muddled.

assuming max reverse thrust

Ah! - but if the thrust reversers didn't operate as they should that would throw all those figures off, wouldn't it?

It was a new jet - delivered in June 2004. So you would think the mechanical bits would be operating properly.... though we all know that's not always the case in reality.

Now, if the runway still had "good" or "fair" braking conditions, as some news sources claim that previous landing aircraft and ATC claim, then a thrust reverser anomaly or malfunction could have possibly contributed to the accident

I have doubts about that braking report, really I do.

....but, like I said, we should let the NTSB determine the probable causes and contributing factors to the incident, no matter how long it takes. In the mean time, the best we can do by discussing this accident and the media's reports on it is by speculating on how an accident like this could be influenced by various factors like the ones mentioned by the media, so long as we understand that those are only speculations at best, and that we must let the NTSB do their work and not jump to any conclusions in the mean time.

Oh, absolutely -- thinking about how such things occur and the forces and other physics involved is mental exercise, but we don't have all the information, there's much to be looked into, and jumping to conclusions should be avoided.

Broomstick, I am very impressed by your contributions to this thread and other aviation topics, especially your "Airport Stories". I am glad to share the skies with those who have the aviators' common-sense like you. May your landings be soft and crosswind-free.

Thank you - that's very kind.

I'll be off to get ready to go to the airport myself soon (pending a good weather report/forecast). And, naturally, one of the first things we'll do after we get there is check the runway conditions....

[Broomstick]

Well, I've a picture of the Southwest jet in a sling being raised by a crane. If folks are interested I'll e-mail to someone who can host the image. If not... then not.

[lukexcom]

Well, I've a picture of the Southwest jet in a sling being raised by a crane. If folks are interested I'll e-mail to someone who can host the image. If not... then not.

Apologies for the late reply.

You can send me the pic, and I'll gladly host it on my SCSU account.

Also, you mentioned in the post above...

You may wish to revisit your altitude assumption - Midway is at 620 MSL. I couldn't retrieve pressure altitude for the time in question, but let's assume it's the standard 29.92 (probably wasn't, but gotta plug something in) at a temperature of 22F/-5C (I remember checking the temp before I headed home) that yields a density altitude of -1,701. Now, I'm no expert on the big jets, but would the density altitude being that low affect the runway distance, meaning that the required distance would be a little shorter than what you posted? Seems to me it would, but given how early it is and that I haven't had my morning caffeine yet I could be a bit muddled.

Yes, indeed, a negative density altitude of that much will lower the distance...maybe 5% (from pressure altitude-adjusted performance), by rough guess, primarily by affecting engine performance. IIRC, I *think* that storm was caused by a low pressure heading west, with the cold front eventually intercepting the warm front, turning into an occluded front eventually until it dissipated...much like the one over Minnesota now, that dumped 6-8 inches of snow on me. So the pressure altitude would be maybe 1000mb to 1005mb or 29.59 in hg to 29.67 in hg, lowering the pressure altitude by 330 ft to 250 ft respectively, from 620 msl. So the landing distance adjusted for pressure altitude would be...maybe 5% lower? 10% less overall? (from standard 29.92 in hg, 15 deg. C, and 1,000ft. pressure altitude conditions on which the table was based on). So in the end, a thrust-reverser faliure would make things very critical indeed.

This topic is a few days old, and I haven't heard much new news about it. Other than maybe posting that pic, I'll keep this thread dead. If this is thread necromancy, my apologies, I'll try to stay out of threads that are on page 2 of the forums. I didn't have a chance to reply to this earlier.

[Broomstick]

You can send me the pic, and I'll gladly host it on my SCSU account.

Could you PM me your direct e-mail? I'm not sure if it's my ancient computer or my own fumblefingerness but I'm having trouble attaching a picture to the SD.net interface.

I think it's an interesting image from the standpoint of here you have this very large, very heavy object lying disabled in a place it was never intended to be, and how the hell do you move that thing? Sure, they unloaded baggage and cargo but even an empty jet is huge and heavy. Logistically, there's the matter of getting such a large crane to the site and set up in less than 24 hours. At least with the local steel mills means there are trucks in the area capable of hauling that much weight. The city and airport were under considerable pressure to get the mess cleaned up, reopen the roads, and reopen the runway. Those are four lane city streets - sidewalks, pedestrian crossings, and nearby homes. Very tight quarters to work in. Set up and moving the airplane had to be done carefully. It took, I think, something like 4-6 hours.

Anyhow - the streets are re-opened and as of Tuesday so was the runway, with at least temporary repairs to the ILS.

As to be expected, the local politicians are trying to profit off the mess, the family of the boy who died are doing a surprisingly good job of avoiding the media for the most part, and tonight we have freezing rain and freezing fog. Ah, Chicago in winter...

I don't think the thread is completely dead, but I don't want to start annoying people, either.

[lukexcom]

Here's the pic of the Southwest 737-700 being lifted by a massive crane. There are also some at airliners.net.

[Broomstick]

The preliminary NTSB report came out. Since I note people are still reading this thread, and no one is screaming "ENOUGH!", I'll throw it in:

************************************************************
NTSB ADVISORY
************************************************************

National Transportation Safety Board
Washington, DC 20594

December 15, 2005

************************************************************

NTSB UPDATE ON SOUTHWEST AIRLINES RUNWAY OVERRUN AT MIDWAY AIRPORT

************************************************************

The National Transportation Safety Board today released the following update on its investigation into the accident involving Southwest Airlines flight 1248, a Boeing 737-700 on December 8, 2005, at Midway Airport in Chicago, Illinois. The airplane overran runway 31C during the landing rollout.

The accident occurred about 7:14 pm central standard time. The airplane departed the end of the runway, rolled through a blast fence, a perimeter fence, and onto a roadway. The airplane came to a stop after impacting two automobiles. One automobile occupant was fatally injured and another seriously injured. The flight was conducted under 14 CFR Part 121 and had departed from the Baltimore/Washington International Thurgood Marshall Airport, Maryland.

The on-scene portion of the investigation has been completed. Additional fact-finding, including tests and research, will be conducted at various component manufacturers. The Safety Board staff continues to examine
the information provided by the flight data recorder and the cockpit voice recorder.

Operations/Human Performance

The two pilots in the cockpit were interviewed on Saturday. Each interview took approximately three hours.

The pilots stated that everything was normal through the point of touchdown. Approaching the airport, weather was of concern to them, and they listened to the ATIS (the recorded weather update) four times during the latter portion of the flight. They stated that they agreed with the dispatcher's assessment of the conditions for landing on runway 31C and backed up that assessment by inputting the numbers into the on-board laptop computer tool.

The computer confirmed that the landing would be within the operational parameters of the airplane and Southwest's procedures, they said. Autobrakes were set on MAX, and they activated after a "firm" touchdown. The flying pilot (Captain) stated that he could not get the reverse thrust levers out of the stowed position. The first officer, after several seconds, noticed that the thrust reversers were not deployed and activated the reversers without a problem. At some point, the Captain noticed that the airplane was not decelerating normally and applied maximum braking manually. The first officer also became aware of the poor braking effectiveness, moved his seat farther forward, and also applied maximum braking. They stated that they continued to apply maximum pressure to the brakes as the airplane went straight off the end of the runway and came to a stop.

Interviews were conducted with a number of other Southwest Airlines flight crews, including the crew of the last Southwest flight to land at Midway and a subsequent crew that diverted to St. Louis.

Airplane Performance

Preliminary calculations show that the airplane touched down with about 4,500 feet of remaining runway and was on the runway for about 29 seconds. Preliminary calculations also show that, for the runway conditions and use of brakes and thrust reverser that occurred, the
stopping distance without hitting obstructions would have been about 5,300 feet (the actual stopping distance was about 5,000 feet). In addition, had the airplane landing into the wind, rather than with a tail wind, the stopping distance for a landing would have been about 1,000 feet less.

At this point, I'd like to interrupt this report to mention that airplanes are, ideally, supposed to touch down within a thousand feet of the beginning of the runway (call it 300 m for you metric folks). They touched down at twice that distance from the start of the runway. To be honest, it's not uncommon to "land long" on a downwind landing - and this case is an illustration of why downwind landings are normally avoided.

What this means is that if they had been landing into the wind they would have been OK. If they had touched down where they were supposed to they would have been OK. If the runway had been dry they probably would have been OK. Of course, that's not what happened.

Documentation of aircraft performance from the scene has been completed to the maximum extent possible. It was not possible to observe tire marks from much of the landing rollout due to the fact that the aircraft landed on a snow-covered runway and snow fell on the runway immediately following the accident.

So, you might ask, how did they know where the airplane touched down?

Couple ways - mark where the airplane stopped, then use the flight data recorder information to calculate backward based on speed and time.

Also, it's entirely possible the FDR was able to record GPS information from the navigation equipment which, combined with touchdown sensors in the landing gear (necessary to engage autobrakes) would be able to determine the actual touchdown point.

FDR data show that autobrakes were active and provided high brake pressure upon touchdown. Autobrakes and manual braking continued to provide high brake pressure throughout the landing roll.

FDR data show that thrust reversers were activated about 18 seconds after touchdown or about 14 seconds before contact with the blast fence. Testing and examination of the thrust reverser systems will continue.

Investigators have obtained the laptop computer tool used by the accident flight crew.

i.e. confiscated it.

It will be examined and calculations of landing performance will be compared to flight manual data.

Eleven security-type video cameras were identified on the airport that may show imagery of the airplane rollout or the surface of the runway and taxiway at the time of the accident. The videos will be reviewed.

Meteorology

National Weather Service forecasters and other personnel were interviewed. An enhanced snow band was in the area producing localized heavy snow due to lake enhancement. This apparently is a somewhat unusual weather phenomenon, as the band swath was only 20 to 30 miles wide with snow accumulations of 10 inches right over Midway Airport.

Midway Airport weather observation equipment and records were examined and all equipment was working normally during the evening of the accident.

Southwest Airlines dispatchers who were associated with the accident flight were interviewed. Prior to the takeoff from Baltimore, when weather conditions deteriorated and the runway switched to runway 31C, the dispatcher determined that runway 31C was approved for landing for flight 1248. Runway conditions, braking action, wind speed and direction, airplane weight and mechanical condition of the aircraft are typical factors considered in making such decisions. The flight was contacted twice on the way to Midway and the appropriateness of using the runway for landing was reaffirmed during both contacts.

Official weather observations:

Approximately 20 minutes prior to the accident, the winds were from 100 degrees at 11 knots, visibility was « mile in moderate snow and freezing fog, the ceiling was broken at 400 feet, and overcast at 1400 feet, temperature -3C, dew point -5C, altimeter setting 30.06 in. Hg. Remarks -
runway 31C rvr (runway visual range) 4500 feet, snow increment - 1 inch of new show in the last hour, 10 inches on the ground.

Approximately 23 minutes after the accident, a special observation revealed winds out of 160 degrees at 5 knots, visibility ¬ mile in heavy snow, freezing fog, sky obscured with a vertical visibility of 200 feet, temperature -4C, dewpoint -5C. Remarks - runway 31C, rvr 3000 feet.

Hmm... that's a density altitude of -1,734 feet. Pretty close to my estimate, although my starting data differed a little from what the NTSB reports.

Toxicology

Blood and urine samples were obtained from both pilots. The disposition of the blood samples is being reviewed.

Structures

The aircraft has been removed from the accident site and was transferred to a hangar at Midway Airport. The maintenance log revealed no writeups or deferred items for the accident flight or several previous flights.

Professional surveyors completed a survey of the accident scene and the geography leading up to the site to include the locations of parts shed by the aircraft after it left the paved runway surface and the blast fence destroyed during the accident sequence.

Powerplants

Both engines were visually examined at the accident site. Although the first stage compressor blades of both engines showed foreign object damage, they were all intact and present. Wood from the blast fence and other debris was present in both engines. A visual examination of the
turbine sections revealed no missing blades.

The 60-day engine history revealed no deferrals or writeups. Each engine has two thrust reverser sleeves. FDR data indicated that all four sleeves were deployed until after the airplane left the paved runway overrun surface. Hydraulic system B (that runs the thrust reversers) revealed
no leaks.

Systems

The Systems Group documented the switches, circuit breakers and controls in the cockpit. The leading edge slat, flap, and trailing edge flap extension measurements were taken and revealed symmetrical extension of all devices. The measurements will be compared to Boeing documentation to determine exact extension.

Chicago Fire Department personnel were interviewed to determine if any switch positions or other items were altered during the rescue effort. The Fire Department Chief stated that the only things his people did were to
disconnect the battery and turn off the crew oxygen source.

The brakes were found in good condition with adequate wear remaining. The main landing gear tires had acceptable tread depth and no indication of flat spots.

Air Traffic Control

The local controller, two tower controllers, and the tower supervisor were interviewed. All controllers stated that they saw the aircraft lights during the landing roll, but did not see the actual touchdown.

The investigation has revealed that runway 31C was used as the landing runway because it contained lower landing minimums for aircraft using the ILS approach. If runway 13C was used, the runway most aligned with the wind, pilots would have been unable to land because of insufficient landing minimums.

Survival Factors/Airports

All flight attendants were interviewed. They all said that they noted a smooth landing but that the deceleration feeling thereafter seem less than usual. They noted that the emergency lighting came on after the airplane came to rest, and one flight attendant opened the L1 door to begin the evacuation. The emergency slide deployed automatically, but its angle in relation to the ground was less than ideal. This caused passengers to begin to pile up around the bottom of the slide. Rescue personnel assisted people away from the slide. The first officer deplaned after about 5 passengers and also assisted in getting people away from the airplane.

Further factual updates will be issued when appropriate.

In sum, it appears the airplane was in good condition and the weather was shit. Looks like human factors are significant, although there's a lot of work still to be done to truly eliminate mechanical failure. No matter what, weather was BIG factor here.

Runway 31C/13C is the longest at Midway. Because of limitations of the guidane equipment at the airport, they couldn't use this pavement to land into the wind. Essentially, Midway has become a one-way airport due to a low cloud ceiling. There were two choices - land downwind, or divert. When you're landing jets that find your airport challenging even in good weather, perhaps, under such conditions, closing the airport and diverting traffic elsewhere would have been the wisest course of action.

Remember, boys and girls, airplane accidents happen for three reasons:

1) Things break (but maybe not here)
2) People make mistakes (check)
3) Only God controls the weather (check)

No, I will not resurrect this thread in a year to year and a half when the final report comes out. If you're still interested at that point go to the NTSB website and look it up yourself.