This particular incident seems to have largely avoided media coverage.
One would have thought that considering recent events, a widebody aircraft forced to descent while experiencing severe turbulence and unreliable airspeed would be of particular interest.
I'm sure that if this had been from manufacturer 'A' rather than manufacturer 'B' there would be media hysteria.
I experienced one encounter with severe turbulence on a 767-300, and while we experience some erratic airspeed info, just like LOT, it returned to normal after the event stopped.
I will add that we were also unable to maintain altitude, and descended. All ended well without injuries. The yoke, thrust levers and flight controls behaved normally, and even though not a single digit on any instrument was readable due to the shaking, the blue above/brown below on the ADI worked just fine. I don't remember the EEC lights, nor cared to look at anything on the overhead panel during the event.
Ask yourself if we would have ended up in some other flight control law or had many more blinking lights and distracting warning bells, alerts or tones had we been in manufaturer "A"'s aircraft (I don't know)
I experienced one encounter with severe turbulence on a 767-300, and while we experience some erratic airspeed info
Did you read the link?
There is a very big difference between 'erratic airspeed info' caused by turbulence/sheer and the textbook definition of unreliable airspeed.The LOT aircraft experienced 'unreliable speed' in the textbook sense.
While the problem was initially resolved as they descended through FL280 it's interesting to note that the problem reoccurred much lower in the descent at around 16000ft.
They had overspeed warnings followed by stick shaker which are indications consistent with a blocked pitot/static system which has led to several fatal accidents including:
The Polskie Linie Lotnicze LOT SA (LOT Polish Airlines SA) Boeing 767-300 series aircraft was on a scheduled IFR flight from Chicago (O'Hare) International Airport, IL (U.S.A.) (KORD) to Warsaw (Okecie) International Airport, Poland (EPWA). The aircraft was en-route when the flight crew reported severe turbulence vicinity of North Bay at approximately 0203Z. The aircraft lost 5,000 feet of altitude (dropping from FL330 down to FL280). The flight crew elected to divert back to Toronto (LBPIA) at 0215Z. The aircraft completed a fuel dump from 0225Z to 0248Z. At 0255Z, the flight crew requested and were given a hold vicinity of the Simcoe VOR at 10,000 feet. At 0248Z (sic), the flight crew advised that they were unable to maintain their altitude and the aircraft climbed through 10,600 feet. At the time, JZA7927 was at 11,000 feet and their flight crew reported receiving a TCAS alert and flew their aircraft in a climb to 12,000 feet. The LOT flight crew commenced their approach to runway 23 at 0302Z. The aircraft landed without incident on runway 23 at 0316Z with ARFF services on standby. Ops. impact -- unknown. Aircraft landed safely runway 23 at 0316 Zulu. Emergency equipment on standby
UPDATE Supplemental information received from T.S.B. Initial Notification [#A09O0117]: The Boeing 767-300 series aircraft (SP-LPA, operated as Polish Airlines flight number LOT2) departed Chicago, O'Hare destined for Warsaw, Poland. In the vicinity of North Bay, Ontario, while cruising at FL330, the aircraft experienced a sudden and uncommanded overspeed condition, stick shaker and illumination of left and right electronic engine control (EEC) caution lights. The aircraft descended to FL280 before the situation was resolved. The aircraft diverted to Toronto (LBPIA) and landed without further incident. The T.S.B. deployed investigators to the site. Note: the class of investigation is being assessed.
Only a bit of turbulence actually. In fact while in cruise they had an ADC failure leading to a sudden overspeed indication on the captain's side. Thrust brought back to idle while the autopilot climbed. Captain disengaged the autopilot and manually pitched further up to 12 degrees until the stall warning activated(along with the continuing overspeed warning). Stickshaker lasted almost 2 minutes intermittently.
After recovery, they diverted to Toronto. There was no longer an overspeed indication at the lower altitudes. While burning off fuel in a hold at 10,000 feet, a separate incident happened as they let the airspeed bleed off after reducing thrust to idle. The stickshaker activated and altitude was lost so 111% thrust was selected but they then climbed up to 10500 and had a TCAS RA.
"LOT Polish Airlines initial and recurrent flight training syllabus does not include practical training for an overspeed warning event. Consequently, flight crews may respond improperly and exacerbate the situation. "
IMHO the apex of the problem and by all means not unique to LOT.
With todays complex systems, and us pilots being mere mortals with all our flaws, no wonder things like this continue to happen. From my point of view, sim sessions are mostly about checking (and checking things that can rarely be practiced beforehand, anyway) rather than training.
Might I suggest a radical makeover of training worldwide - to include training rather than just checking (disguised as training), with a substantial increase in quantity, such as 8-12 sessions pr year, divided into 4 or 6 blocks?
While the 4-hour sim slots might be effective for checking, they are not very effective for learning. Learning is a change in behaviour as a result of experience - too much stuff in too little time rarely produces the desired effect.
An (almost) cost-neutral way of utilising the sim would be to do two-hour blocks, twice pr crew. Let's say 1 hour brief - 2 hours sim - 0:45 debrief, 0:30 lunch, 0:45 brief - 2 hours sim - debrief. Same sim time, more time for organizing one's thoughts.
As long as a system like this (increased training quantity) would be mandated, it would not be an competitive disadvantage for anyone. It's a win-win situation. A modest increase to 3 or 4 sessions pr year would even be a great start.
This event should unite Airbus /Boeing pilots to a degree, as we can see very clearly,that despite (fortunately ) a different outcome, the similarities of how a crew failed to adequately contain this scenario, is the most worrying aspect. Failure to cross-check instruments, & cross check data against basic parameters of thrust/pitch attitude/ IRS derived ground-speed etc, is the single most basic omission in attempting to contain /trouble shoot.
Easy to say from behind the safety of a keyboard, but this most basic requirement is the one that will kill you , in the modern electronic aircraft, just as surely as it will on a dinosaur from a previous age.
As has been said so often, we need to remember what a "PILOT" is, & provide him with enough training/practice to maintain his basic skills at an adequate level, for the day when he may need them. . big time.
I heard 2nd or 3rd hand that the IAA had been "persuaded" by Ryanair that 8hrs per year (rather than the 8hrs - reduced if I remember a couple of years back to 6 ? - every 6mths we were previously assumed to require) was in fact more than adequate. If this is the best a "Regulator" can do against blatant commercial interest & Sod safety/competence, not much hope for our skills being honed any time soon. Or maybe they think we should all dig deep into our pockets & come along & buy some extra training, just to feel that little bit safer ?
Failure to cross-check instruments, & cross check data against basic parameters of thrust/pitch attitude/ IRS derived ground-speed etc, is the single most basic omission in attempting to contain /trouble shoot.
Agree. I wonder if the simple IAS DISAGREE and/or ALT DISAGREE advisory message only would not produce a better result in terms of pilot reaction. OVERSPEED WARNING is powerfull enough to rush a crew to react to it without further thinking.
Interesting to note what dust and dirt can do to a computer.
Had a similar event a few years ago in a B737-800, due to an ADC failure. Passing through FL180 in climb, ASI on Capt's side showed low airspeed / black and white checked bars closely followed by stick shaker. Cross checked instruments with F/O's and standby, flew pitch and power settings and returned to base. All returned to normal in descent.
Had a similar event a few years ago in a B837-800, due to an ADC failure. Passing through FL180 in climb, ASI on Capt's side showed low airspeed / black and white checked bars closely followed by stick shaker. Cross checked instruments with F/O's and standby, flew pitch and power settings and returned to base. All returned to normal in descent.
I would have a few questions : Was the ADC failure detected by the system and announced as such ? Was the AP or the pilot following erroneous FD commands ? Was the stick shaker justified ? Thanks
I'm sure that if this had been from manufacturer 'A' rather than manufacturer 'B' there would be media hysteria.
It has nothing to do with manufacturers and everything to do with the fact that a bunch of dead buddies makes it much better story to pursue in the case of 'A'. It's stupid, yes, but this is why the web has a chance to change things, eliminating monopoly of the usual tabloids.
There are more idiocies like that. In the present world a military pilot that gets shot down becomes a celebrity and a millionaire while the one that does not get shot down remains poor.
That said, I often wondered why on earth the avaition industry does not get rid of these idiotic pitot tubes altogether or at least have a backup of a different type. We now have much more reliable ways to measure air speed. For example this:
Yes, mass flow sensor measures mass flow, but electronics can easily calculate speed if you know the current air pressure and temperature - which every plane has to know.
Unlike pitot tube, the mass sensor cannot freeze, it is much less prone to contamination, and it is far more precise. Almost every car currently produced uses those and nobody would even think of using something like a pitot tube in their place, in spite of the fact that pitot tubes are significantly cheaper.
The theory of operation of such a sensor is quite simple - you heat a piece of metal and measure how much energy you require to keep it at a constant temperature. The more air flows over the sensor, the more energy is required to keep it at constant temperature. An aviation version of such a sensor could simply be a piece of wire/metal rod protruding from fuselage.
They controlled the airplane and kept things under control. It is amazing what a big fat yoke and attitude indicator can do to accomplish that. Who cares if you lose airspeed in a 767. Just get the unreliable airspeed chart out when you find the time.
