Southwest Airlines grounds 81 planes after emergency

Reuters ^ | Sat Apr 2, 2011 10:57am EDT | David Schwartz

[Paleo Conservative]

(Reuters) - Southwest Airlines grounded 81 aircraft from its Boeing 737 fleet for inspection after a gaping hole in the fuselage forced one of its planes to make emergency landing in Arizona on Friday, the company said on Saturday.

Southwest (LUV.N) and Boeing (BA.N) engineers will inspect the aircraft to try to determine the cause, Southwest said in a statement. Passengers heard a loud noise and suddenly saw a hole about mid-cabin.

Southwest Airlines is working with the National Transportation Safety Board and the Federal Aviation Administration on the ground in Arizona to determine the cause of a sudden drop in cabin pressure on Southwest Flight 812 from Phoenix to Sacramento on Friday, airline officials said.

[NittanyLion]

Otherwise, you’d have some internal force pushing its way out and leaving the plane with edges pointing outward from the exiting force.

You do have an internal force - air. At 30K feet, it's pushing out at something like 10 pounds of force per square inch.

[Ernest_at_the_Beach]

Something rather strange in that flight record.....

****************************EXCERPT******************************

06:56PM	33.67	-113.97	282°	West	410	472	33,400	1,320	Los Angeles Center
06:57PM	33.69	-114.10	282°	West	405	466	34,400	-1,380	Los Angeles Center
06:58PM	33.71	-114.23	276°	West	400	460	30,700	780	Los Angeles Center
06:59PM	33.72	-114.37	269°	West	412	474	36,000	-5,520	Los Angeles Center
07:00PM	33.72	-114.51	261°	West	428	493	19,700	-10,740	Los Angeles Center
07:01PM	33.71	-114.65	260°	West	423	487	14,600	-4,320	Los Angeles Center
07:02PM	33.69	-114.77	257°	West	407	468	11,100	-1,860	Los Angeles Center
07:03PM	33.67	-114.88	283°	West	369	425	10,900	-60	Los Angeles Center
********************************************** Notice at 34,000 altitude then went down to 30,000 then zoomed up to 36,000 then back down to 30,000. That would really be fighting if that is in fact what happened...

[slotin flash]

Saved for later.

[Ernest_at_the_Beach]

Maybe the altimeter was starved for air??

[Strategerist]

Has Jack Cashill finished his book about how it was caused by a missile yet?

[ecomcon]

That was my thought also. I suppose terrorism has been ruled out already, per sop.

[Christian Engineer Mass]

That problem was dealt with 50 years ago.

[Moose4]

There was a case in the 1970s on a National Airlines DC-10 where one of the wing engines had an uncontained engine failure and shot a fan blade through one of the windows, popping it out at 39,000 feet. One passenger was ejected. That’s the only time I’ve ever heard of a hole anywhere near the size of the one on that SWA flight causing someone to be ejected. Aloha 243 lost a massive portion of the roof, something like the first four or five rows of seats were completely exposed down to the floor. It’s a miracle that only the one flight attendant was blown out.

“Pieces of the engine fanblades struck the fuselage breaking a window near seat 17H. According to a witness, the occupant of the seat was partially forced through the window opening and was temporarily retained in this position by his seatbelt. Efforts to pull the passenger back into the airplane by another passenger were unsuccessful, and the occupant of seat 17H was subsequently forced entirely through the cabin window.” (from http://www.super70s.com/Super70s/Tech/Aviation/Disasters/73-11-03%28National%29.asp )

This airplane was a 737-300 that was delivered new from the factory to SWA in 1996. It had around 40,000 landing/takeoff pressurization cycles on it. That’s about half the expected life of a 737 airframe.

}:-)4

[freedumb2003]

>>You don’t fall 30,000ft in most car accidents.<<

You are just as dead at 55 MPH at 3 feet.

[Loud Mime]

My gawd....a 24ft reserve, shot and a half capewells and a motorcycle skidlid? That guy’s going to die!!

[gorush]

Give me a break...it was 1975. D7166. I retired with a..stratocruiser I'm the guy in the middle...

[AGreatPer]

Oh come on, that is purely a simple fatigue failure.
It is simply going to happen sometimes depending upon how that plane was used, etc.

[gorush]

Correction, now I remember, it was a “CruiseAir”.

[gorush]

So what makes you so conversant on those cut-away devices?

[Loud Mime]

I had one of the first ParaPlanes. SCS 1299 with six friggin 7-man night stars. Needed a splash for my D. Good going, guy!

[gorush]

SCS 4429, SCR 8604, FFB 693 :{) This brings back great memories, thanks.

[gorush]

The night was right!

[CedarDave]

This plane is relatively new -- built in 1996

I caught a segment on Fox this morning. Southwest has contracted out major maintenance to San Salvador, a location where English is not the language. The feds don't do many inspections out of country and in this case they are required to notify the facility prior to their arrival.

I only fly on Southwest but this may make me rethink my travel arrangements.

[GOPmember]

These numbers suggest that the plane descended from 36,000 feet to 19,700 feet between 6:59 and 7:00 PM, or 16,300 feet in one minute.

In other words, if the data are actually correct, it looks as if the plane descended at an average rate of 16,300 feet/min = 271.7 feet/sec during this one minute period.

So, I don’t understand what the number under “rate” indicates. Maybe my math is bad. Or, maybe someone can clue me in.

Anyway, a 271.7 feet/sec descent can’t be a walk in the park. Because, according to the all-knowing Wikipedia, the terminal velocity of a skydiver is in the neighborhood of 122 mph (or, about 178 feet/sec).

[NavyCanDo]

It looks to be the approximate location of one of the fuselage mounted antennas. Could have been metal fatigue where the antenna attaches to the fuselage or when the antenna was last replaced or serviced it was not installed correctly. Just a guess from someone who builds these planes.

You can see one of these antennas in this photo, just in front of the tail fairing.

http://cdn-www.airliners.net/aviation-photos/middle/8/1/7/1503718.jpg