The question that comes to mind is this: Why hasn't this surfaced before on A330s? Suddenly, two events within a month?
I am willing to bet that such loss of airspeed sensors is more common than the average person thinks, but by reporting this, it makes it look like a design flaw.
Any aircrew out there who can comment?
Dont’ know about the big airliners, but when I was an undergrad pilot training instructor pilot, I’d have my students memorize power settings for a given airspeed, both in level flight, and during landing maneuvers. That way, a failure of the pitot/static system would not prove disastrous. Sounds like that pilot had the same training.
As for the Airbus - if it ain’t Boeing, I ain’t going.
Uh-oh! The next sound you hear is the mass scurrying of lawyers across the Atlantic!
Bookmark
And there's the key - the A330 was still working properly. The crew just had to know when to disregard incorrect feedback from the computers and instruments and do some old-fashioned flying - admittedly a tall order in an era when people have been conditioned to rely on automation for so many things.
GPS on Tomtom etc tells you how fast you’re going. 3d vs. 2d makes this impossible in the air?
The loss of airspeed sensing is extremely rare. However, crews are trained to set certain power settings and fly at specific pitch attitudes that will give them a margin of safety above the stall and below the buffet at the altitude and weight where they are operating. All modern aircraft have attitude indicators that are independent of the 'computer system' as back ups. 'Die by wire' systems are slightly different in that the power sensing and control may be more difficult to set manually due to the computer wanting to maintain authority. In any event, given the time and crew recognition of the problem it should be within their capability to safely fly the plane. Training,experience and knowledge of procedures...wash...rinse...repeat.
The following is making the rounds among air line pilots and was sent to me by a Brazilian pilot of whom I am quite proud. He lived with us as an exchange student many years ago and knows my interest in aviation.
****************
Subject: Air France Accident: Smoking Gun Found
A Brazilian Naval unit reportedly found the complete vertical
fin/rudder assembly of the doomed aircraft floating some 30 miles from the
main debris field. The search for the flight recorders goes on, but given
the failure history of the vertical fins on A300-series aircraft, an
analysis of its structure at the point of failure will likely yield the
primary cause factor in the breakup of the aircraft, with the flight
recorder data (if found) providing only secondary contributing phenomena.
The fin-failure-leading-to-breakup sequence is strongly suggested in
the attached (below) narrative report by George Larson, Editor emeritus of
Smithsonian Air & Space Magazine.
It’s regrettable that these aircraft are permitted to continue in
routine flight operations with this known structural defect. It appears
that safety finishes last within Airbus Industries, behind national pride
and economics. Hopefully, this accident will force the issue to be
addressed, requiring at a minimum restricted operations of selected
platforms, and grounding of some high-time aircraft until a re-engineered
(strengthened) vertical fin/rudder attachment structure can be
incorporated.
Les(George Larson’s Report)-——————————
This is an account of a discussion I had recently with a maintenance
professional who salvages airliner airframes for a living. He has been at
it for a while, dba BMI Salvage at Opa Locka Airport in Florida. In the
process of stripping parts, he sees things few others are able to see. His
observations confirm prior assessments of Airbus structural deficiencies
within our flight test and aero structures communities by those who have
seen the closely held reports of A3XX-series vertical fin failures.
His observations:
“I have scrapped just about every type of transport aircraft from
A-310, A-320, B-747, 727, 737, 707, DC-3, 4, 6, 7, 8, 9, 10, MD-80, L-188,
L1011 and various Martin, Convair and KC-97 aircraft.
Over a hundred of them.
Airbus products are the flimsiest and most poorly designed as far as
airframe structure is concerned by an almost obsession to utilize composite
materials.
I have one A310 vertical fin on the premises from a demonstration I
just performed. It was pathetic to see the composite structure shatter as
it did, something a Boeing product will not do.
The vertical fin along with the composite hinges on rudder and
elevators is the worst example of structural use of composites I have ever
seen and I am not surprised by the current pictures of rescue crews
recovering the complete Vertical fin and rudder assembly at some distance
from the crash site.
The Airbus line has a history of both multiple rudder losses and a
vertical fin and rudder separation from the airframe as was the case in NY
with AA.
As an old non-radar equipped DC4 pilot who flew through many a
thunderstorm in Africa along the equator, I am quite familiar with their
ferocity. It is not difficult to understand how such a storm might have
stressed an aircraft structure to failure at its weakest point, and
especially so in the presence of instrumentation problems.
I replied with this:
“I’m watching very carefully the orchestration of the inquiry by French
officials and Airbus. I think I can smell a concerted effort to steer
discussion away from structural issues and onto sensors, etc. Now Air
France, at the behest of their pilots’ union, is replacing all the air data
sensors on the Airbus fleet, which creates a distraction and shifts the
media’s focus away from the real problem.
It’s difficult to delve into the structural issue without wading into
the Boeing vs. Airbus swamp, where any observation is instantly tainted by
its origin. Americans noting any Airbus structural issues (A380 early
failure of wing in static test; loss of vertical surfaces in Canadian fleet
prior to AA A300, e.g.) will be attacked by the other side as partisan,
biased, etc. “
His follow-up:
One gets a really unique insight into structural issues when one has
first-hand experience in the dismantling process.
I am an A&P, FEJ and an ATP with 7000 flight hours and I was absolutely
stunned, flabbergasted when I realized that the majority of internal
airframe structural supports on the A 310 which appear to be aluminum are
actually rolled composite material with aluminum rod ends. They shattered.
Three years ago we had a storm come through, with gusts up to 60-70
kts., catching several A320s tied down on the line, out in the open.
The A320 elevators and rudder hinges whose actuators had been removed
shattered and the rudder and elevators came off.
Upon closer inspection I realized that not only were the rear spars
composite but so were the hinges. While Boeing also uses composite
material in its airfoil structures, the actual attach fittings for the
elevators, rudder, vertical and horizontal stabilizers are all of machined
aluminum.”
NTSB should ground all A330’s until this problem has been fixed.
"Tuesday 23rd June, 2009 10am enroute HKG to NRT. Entering Narita Japan airspace.
"FL390 mostly clear with occasional isolated areas of rain, clouds tops about FL410. "Outside air temperature was -50C TAT -21C (you're not supposed to get liquid water at these temps). We did.
"As we were following other aircraft along our route. We approached a large area of rain below us. Tilting the weather radar down we could see the heavy rain below, displayed in red. At our altitude the radar indicated green or light precipitation, most likely ice crystals we thought.
"Entering the cloud tops we experienced just light to moderate turbulence. (The winds were around 30kts at altitude.) After about 15 seconds we encountered moderate rain. We thought it odd to have rain streaming up the windshield at this altitude and the sound of the plane getting pelted like an aluminum garage door. It got very warm and humid in the cockpit all of a sudden. Five seconds later the Captain's, First Officer's, and standby airspeed indicators rolled back to 60kts. The auto pilot and auto throttles disengaged. The Master Warning and Master Caution flashed, and the sounds of chirps and clicks letting us know these things were happening.
"Jerry Staab, the Capt. hand flew the plane on the shortest vector out of the rain. The airspeed indicators briefly came back but failed again. The failure lasted for THREE minutes. We flew the recommended 83%N1 power setting. When the airspeed indicators came back we were within 5 knots of our desired speed. Everything returned to normal except for the computer logic controlling the plane. (We were in alternate law for the rest of the flight.)
"We had good conditions for the failure; daylight, we were rested, relatively small area, and light turbulence. I think it could have been much worse. Jerry did a great job flying and staying cool. We did our procedures called dispatch and maintenance on the SAT COM and landed in Narita. That's it."
Warm rain at FL390. I bet there was a hailstorm down on the ocean below.
Pitot tubes are supposed to prevent such crap from happening. The thing is Air France knows, and knew about before hand, that the pitot tubes on A330s were defective and was in the process of replacing them. Why they are still flying A330s with the bad ones I don’t know, at least I am assuming this particular Airbus had the defective tubes.
The miracle of the Gimli Glider was an example of how valuable fundamental knowledge of low-tech/no-tech flying can be. The 69 souls who were on board definitely owe their lives to the fact the the captain just happened to pursue a glider-flying hobby in his spare time, and thus had the skills and knowledge to successfully fly and land a Boeing 767 which had abruptly and irreversibly turned into a "glider" at 41,000 feet. http://en.wikipedia.org/wiki/Gimli_Glider
Well, I'm sure you have all heard of the Air France accident. I fly the
same plane, the A330.
Yesterday while coming up from Hong Kong to Tokyo, a 1700nm 4hr.
flight, we experienced the same problems Air France had while flying
thru bad weather.
I have a link to the failures that occurred on AF 447. My list is almost
the same.
http://www.eurocockpit.com/images/acars447.php
The problem I suspect is the pitot tubes ice over and you loose
your airspeed indication along with the auto pilot, auto throttles and
rudder limit protection. The rudder limit protection keeps you from over
stressing the rudder at high speed.
Synopsis;
Tuesday 23, 2009 10am enroute HKG to NRT. Entering Nara Japan airspace.
FL390 mostly clear with occasional isolated areas of rain, clouds
tops about FL410.
Outside air temperature was -50C TAT -21C (your not supposed to get
liquid water at these temps). We did.
As we were following other aircraft along our route. We approached
a large area of rain below us. Tilting the weather radar down we could
see the heavy rain below, displayed in red. At our altitude the radar
indicated green or light precipitation, most likely ice crystals we
thought.
Entering the cloud tops we experienced just light to moderate
turbulence. (The winds were around 30kts at altitude.) After about 15
sec. we encountered moderate rain. We thought it odd to have rain
streaming up the windshield at this altitude and the sound of the plane
getting pelted like an aluminum garage door. It got very warm and humid
in the cockpit all of a sudden.
Five seconds later the Captains, First Officers, and standby airspeed
indicators rolled back to 60kts. The auto pilot and auto throttles
disengaged. The Master Warning and Master Caution flashed, and the
sounds of chirps and clicks letting us know these things were happening.
Jerry Staab, the Capt. hand flew the plane on the shortest vector
out of the rain. The airspeed indicators briefly came back but failed
again. The failure lasted for THREE minutes. We flew the recommended
83%N1 power setting. When the airspeed indicators came back. we were
within 5 knots of our desired speed. Everything returned to normal
except for the computer logic controlling the plane. (We were in
alternate law for the rest of the flight.)
We had good conditions for the failure; daylight, we were rested,
relatively small area, and light turbulence. I think it could have been
much worse. Jerry did a great job fly and staying cool. We did our
procedures called dispatch and maintenance on the SAT COM and landed in
Narita. That's it. From what I gathered on Airliners.net, there have been 35 previous incidents with the A330.