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-   -   American Airlines Two Planes Grounded After Tail Strikes (http://www.pprune.org/rumours-news/440189-american-airlines-two-planes-grounded-after-tail-strikes.html)

airman1900 20th Jan 2011 12:21

American Airlines Two Planes Grounded After Tail Strikes
 
From Wall Street Journal, Jan. 20, 2011 page B4:

Two Planes Grounded After Tail Strikes
By ANDY PASZTOR
A recent spate of safety lapses by American Airlines, including a Boeing 757 that apparently took off at an unusually slow speed and slammed its tail on a California runway last week, are prompting concerns among federal safety officials as well as some of the carrier's pilots and mechanics.

None of the incidents resulted in injuries, though two planes suffered enough damage to warrant temporarily taking them out of service. An airline spokeswoman said "we take each incident very seriously," various internal reviews are under way to understand the causes, and American usually works together with labor and government officials "to make sure these types of incidents are mitigated."
She didn't provide details of what precipitated the operational problems.
Federal officials are conducting their own investigations into a number of incidents ranging from last week's takeoff error at Los Angeles International Airport to a botched landing in late December that resulted in a jet carrying 181 people running off the end of a snowy Jackson Hole, Wyo., runway.
The takeoff mistake in Los Angeles ended with the Hawaii-bound Boeing 757—piloted by a senior-management captain who is the chief pilot for 757 crews based in Los Angeles—quickly returning to the field. The aircraft may have suffered significant damage from what is called a "tail strike," which usually happens when the takeoff angle is too steep and the rear portion of a departing jet's underbelly hits or drags on the runway.
The heavily loaded Boeing 757 was taken out of service and may need repairs to its rear bulkhead, according to people familiar with the details.
The plane was ferried to American's Tulsa, Okla., maintenance base earlier this week, without passengers and under rules requiring the pilots to fly at lower altitudes in order to reduce structural stresses from pressurizing the fuselage.
A Federal Aviation Administration spokesman said the agency is investigating the Los Angeles tail strike and safety experts are "assessing the extent of the damage to the bulkhead." The National Transportation Safety Board also has looked into the incident. Tail strikes occur from time to time, mostly on longer models such as Airbus A340 or Boeing 767 and 777 jets, but safety experts said they are particularly unusual during takeoffs of 757 jets.
Greg Smith, the management captain who was in command of the flight, didn't respond to questions, and the American spokeswoman said employees aren't authorized to speak to reporters.
In the past few weeks, the AMR Corp. unit also experienced a separate tail strike at Los Angeles Airport involving a Boeing 737 taking off for Canada. American said it didn't tell U.S. or Canadian investigators about the event because the damage wasn't significant enough to warrant such reports. The plane, however, remains out of service, pending a decision slated for next week by American's engineering and maintenance experts. At a minimum, according to people familiar with the matter, the aluminum skin around the plane's tail was damaged.
In early January, yet another American jet, this time a Boeing 767 wide-body aircraft, had to return to New York's John F. Kennedy International Airport shortly after takeoff, when its nose gear wouldn't retract. After making a safe but overweight emergency landing, it turned out that mechanics had failed to remove a pin installed during overnight maintenance.
The New York incident has attracted attention from American pilots and mechanics because such pins have red-and-white streamers attached to them, reminding crews to "Remove Before Flight." None of the mechanics, baggage handlers or other ground staff noticed the pin prior to the plane's beginning its taxi for takeoff. The aircraft's pilots, who are responsible for visually checking the condition of every aircraft prior to flight, also missed the pin.
The American spokeswoman said the airline doesn't publicly "discuss corrective actions" affecting pilots.
At least three of American's recent incidents featured some unusual factors, and that's partly why they have sparked intense scrutiny from different groups.
The staff of the safety board, for example, appears especially interested in figuring out why the experienced captain in the Jackson Hole event failed to manually deploy panels on top of his jetliner's wings to help decelerate the speeding plane after touchdown. The panels failed to deploy automatically as the cockpit crew expected. Investigators are examining whether a maintenance mix-up contributed to that failure, and somehow also may have helped delay deployment of devices at the rear of the engines intended to slow the jet by reversing the direction of engine thrust.
Initially, the pilots of the Boeing 737 that scraped its tail climbing away from Los Angeles didn't realize anything unusual had happened. But during the flight, according to people familiar with the details, flight attendants alerted the cockpit crew that they had heard sounds of creaking metal after the jet's tail smacked the runway.
The Boeing 757 damaged during takeoff from Los Angeles may have been climbing at a speed of less than 120 miles an hour, according to people familiar with the details. That's markedly slower, these people said, than such a 110-ton jet typically would be flown in order to lift safely off the ground.
Write to Andy Pasztor at andy.pasztor@wsj.com
Copyright 2011 Dow Jones & Company, Inc. All Rights Reserved

Mercenary Pilot 20th Jan 2011 13:03

Quote:

piloted by a senior-management captain
Investigation over. :E

sevenstrokeroll 20th Jan 2011 13:52

mercenary pilot... seems to know how things really are.

I would like to know if the rate of rotation was too quick on the hawaii bound plane.

but seriously...if the plane wasn't loaded as the weight and balance info (numbers) said, the trim setting may have been wrong for takeoff.

that bit about the nose gear pin is a bit disturbing though. we kept our pins onboard the plane , checked them on the walk around and counted them in the cockpit.

PEI_3721 20th Jan 2011 13:55

I recall some Boeing data, several years ago, which showed a cyclic pattern to 757 tailstrikes. IIRC this was against fleet flight-hours which at that time equated roughly to a two and a half year period. Boeing were investigating reasons for this, some of which were that pilots progress through the industry, training programs evolved to match new priorities, and that humans (management, training and crews) forget the context or priority of safety initiatives.

I have seen and generated similar safety data which showed a cyclic pattern. Patterns probably can be found in any data, but with some circumstantial correlation from the items above, I wonder if there are any other safety patterns or studies which might help the safety of our industry.
The items all appear to be aspects of change, thus is the pattern a function of change management?

Sqwak7700 20th Jan 2011 15:46

Quote:

Investigation over.
So true. What's the saying - those who can't, manage? That is the biggest threat, a manager at the controls. :eek:

Quote:

I would like to know if the rate of rotation was too quick on the hawaii bound plane.
I hate to quote journos, but it sounds like rotation at the wrong speed;

Quote:

The Boeing 757 damaged during takeoff from Los Angeles may have been climbing at a speed of less than 120 miles an hour,
Again, this is coming from a journo. but a Hawaii bound 757, or even a lightly loaded one should not be climbing out at 120 (assume he means rotation?). Maybe this management genius mistook the V1 call and began rotating? I've seen it happen before with new pilots when they are nervous, which could happen to someone out of their element (ie, flying only enough to stay current.)

Anyway, tailstrikes on a 75 do seem quite rare. :confused:

411A 20th Jan 2011 16:05

American Airlines...again.
It should be remembered that it was a 'senior management pilot' that crashed his MD-80 at Little Rock, trying to land in a thunderstorm.

Perhpas...management pilots need to stay firmly in the office, or...have a bit more regular line flying experience.:rolleyes:

aterpster 20th Jan 2011 16:26

411A:

Quote:

Perhpas...management pilots need to stay firmly in the office, or...have a bit more regular line flying experience.
Depends on what the management pilot does. If he gives line checks all the time he (she) is probably fine. If, however, he/she is a "chief pilot" office paper shuffler, then watch out.

At my airline the latter type usually were smart enough to assign a "F/O" to their occasional currency flight who was, in fact, a sharp check airman.

lomapaseo 20th Jan 2011 17:37

I always interpreted a management pilot to be one who exhibits strong personality traits and opinions without the currency of flying the actual product.

Much like the opinions we often see posted on PPrune:E

stepwilk 20th Jan 2011 17:45

Since I have never flown aircraft long and powerful enough to whack their tails, can somebody explain to me what causes tailstrikes?

Yes, I understand that overrotation "causes" the strike, but what leads to the overrotation? Simple carelessness? Pulling too hard/fast? Not paying attention to the proper pitch indication? Nervousness about too long a takeoff roll? It seems so simple that if 10 degrees is a proper rotation and 12 degrees will hit the tail, you don't let the little veebird go past 10.

Or am I missing something?

bearfoil 20th Jan 2011 17:54

Lack of sufficient a/s, (Lift) to leave the ground. Once committed, one gets airborne, or plows ahead into the Autobahn, Beach, Snow bank. 100 knots probably not enough velocity, imo.

hetfield 20th Jan 2011 18:54

These incidents/mistakes happen frequently.

In our airline we had a summary about it. To make it short, mostly it was due to wrong inputs in the FMS e.g. wrong weights, or wrong flap settings, or a combination of both.

gulfairs 20th Jan 2011 19:05

When I was an apprentice pilot I recall being admonished for rotating to quickly in an L188c aircraft. fortunately that type of machine just got up and flew, but the admonishment stuck in my memory core right thru my career thru to the big heavies.
The growling I received from a long deceased crusty old Captain was
"When-you-rotate-you-will-count-to-three!"
I even used it when were were running out of cement at Gatwick, right on the last 500ft mark before the piano keys.

misd-agin 20th Jan 2011 19:11

bbg - a better technique would be to use the 'NY decimal' system for your 'count'

That's a one...
That's a two...
That's a three...

By then the plane will have left the ground and the tail would be clear of the runway. :ok:

sevenstrokeroll 20th Jan 2011 20:40

pei3721

re: cyclic: it all boils down to ''fundamentals''...you are never too good to practice the fundamentals in the sim.

I prefer the Lawrence Welk counting method to the NY method...ahoneannatwoo anna you know what to do

Airbubba 20th Jan 2011 23:24

Quote:

Tail strikes occur from time to time, mostly on longer models such as Airbus A340 or Boeing 767 and 777 jets, but safety experts said they are particularly unusual during takeoffs of 757 jets.
I'll have to agree with that statement. The 75 is not that light in pitch compared to other planes I've flown. Also, the tail clearance is fairly generous for a long aircraft.

A couple of the classic causes for takeoff tail strikes are setting the airspeed bugs wrong and trying too agressively to achieve the 'ideal' 2 degree per second pitch rate they harp about in the sim.

bubbers44 20th Jan 2011 23:31

When you fly once a month as a management pilot you are at the same proficiency as a line pilot flying once a month. Striking a tail out of LAX with about 12,000 feet of runway would never happen with a line pilot. I don't care how mistrimmed it was if the W&B was off. I thought it was an SNA take off when I heard about the tail strike. But at LAX?

I had a friend that had his captain screw up and not set the flaps in a 737 out of LAX one day when maintenance pulled the takeoff warning circuit breaker to not hear that annoying sound about flaps everytime they advanced the thrust levers. They didn't get a tail scrape but did a stick shacker on lift off. My friend should have caught it too but he didn't. Unless I was flying out of SNA I let the airplane fly itself off the runway with proper pitch and not worry because I had 8,000 ft in front of me at rotation. I guess management guys know something we don't.

JammedStab 21st Jan 2011 02:18

Quote:

Originally Posted by stepwilk (Post 6191921)
Since I have never flown aircraft long and powerful enough to whack their tails, can somebody explain to me what causes tailstrikes?

Yes, I understand that overrotation "causes" the strike, but what leads to the overrotation? Simple carelessness? Pulling too hard/fast? Not paying attention to the proper pitch indication? Nervousness about too long a takeoff roll? It seems so simple that if 10 degrees is a proper rotation and 12 degrees will hit the tail, you don't let the little veebird go past 10.

Or am I missing something?

It seems that frequently when someone in a large jet tries to takeoff erronously with the flaps up or with V-speeds much lower than they should be for their heavy weight, that they end up with a tailstrike. A good example is the 727 in Dallas many years back.

So here is my question. Why does the tail strike happen. I assume that these particular pilots know not to exceed a certain pitch angle. 10° nose-up on the 727 was about the max you wanted with the mains still on the ground.

So is it because the pilot flying rotates, does not lift off and then tries to force the aircraft in the air. I don't think that a pitch instability would be involved as the tail is probably flying fine. If I ever happen to encounter this situation on the 727 where I am at my 10° noseup attitude and not lifting off, aside from adjusting thrust, what do you recommend in terms of pitch. I might be tempted to lower the nose.

Just curious.

Gulfcapt 21st Jan 2011 02:35

This is worse than a string of bad luck. Something isn't right at AA and they need to get to the bottom of it.

Best,
GC

bearfoil 21st Jan 2011 02:57

I think China had a TS not too long ago, in a 340. At the end of the Runway, and with bugs missing a few legs, Captain had to get airborne or plow through the fence and into some buildings. He chose flight over certain death. 30-50 million dollars and possibly a Hull loss, he did what he had to do. Keep pulling until it gets off the ground. the alternative is to not raise (or even lower) the nose, and start virtually over. Reject the T/O when you cannot stop in time, or cost the Company an airplane, or at least a gazillion Euros, (Yuan). Live, and learn Bartending.

sevenstrokeroll 21st Jan 2011 03:13

I seem to recall that the 727 has a tail skid (retractable)...so does the DC9 series, though it is called a bumper.

ok, a managment pilot bumped the tail...its the old line:

1 week away from flying and I FEEL IT
2 weeks away from flying and my copilot feels it
3 weeks away from flying and my passengers feel it
4 weeks away from flying and a tail strike happens.
5 weeks away from flying and they make me a chief pilot


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