Dec 20th 2010
A Germanwings Airbus A319-100, registration D-AGWK performing flight
4U-753 from Vienna (Austria) to Cologne (Germany) with 144 passengers
and 5 crew, was on approach to Cologne when the crew reported smoke in
the cockpit. The airplane continued for a safe landing. Paramedics
needed to treat both flight crew at the airport and subsequently took
them to a hospital. The cause of the smoke is unknown.
Sep 27th 2012
The German BFU released their preliminary report in German
stating, that both flight crew became partially incapacitated within
seconds following a strong burning electrical smell on base leg and
during intercept of the localizer. The captain's oxygen level in his
blood fell substantially below 80%, the first officer's oxygen level
below 80% (normal value 95-98%). The first officer was in sick leave for
6 months following the event.
The flight had been delayed due to
heavy snowfall in Cologne. The aircraft finally departed Vienna with a
delay of 3 hours, the flight was uneventful until the aircraft turned
onto the left base leg for Cologne's runway 14L when both flight crew
smelled a strong electrical burning odour. Upon query the purser
reported no smell in the cabin. The odour seemed to subside after a
brief moment.
While the aircraft turned to intercept the
localizer the first officer reported he felt seriously sick close to
vomiting (German "kotzübel"), he smelled a strong electrical sweet odour
and would don his oxygen mask. Alerted by that remark the captain
noticed his legs and arms were tickling, his senses were literally
vanishing and his sight abruptly reduced to a tunnel view. He too donned
his oxygen mask. The first officer needed two attempts to don his
oxygen masks. After both flight crew had donned their oxygen masks, the
captain improved slightly, while the first officer's condition continued
to deteriorate.
The captain (35, ATPL, 7,864 hours total, 3,107
on type) instructed the first officer (26, CPL, 720 hours total, 472
hours on type) to advise approach they would immediately contact tower
and to declare Mayday on tower. While the first officer was
communicating with tower declaring emergency and reporting strong smell
in the cockpit the tower instructed an aircraft ahead of the A319 to go
around, the aircraft established on the glide path, the captain, pilot
flying, selected flaps 1 himself and disengaged the autopilot now flying
manually. The aircraft was flying too fast (around 220 KIAS), the
captain therefore deployed spoilers, instructed the first officer
therefore to lower the gear and later to select flaps 2.
At that
point the first officer felt overwhelmed, he could no longer overview
the scenario, could no longer process the arriving information and had
difficulty to focus on single aspects of the scenario. The captain felt
that while manually flying the aircraft he was at the upper limit of
what he was capable to do in his bad bodily shape.
After the
crew managed to configure the aircraft for landing, the aircraft was
still too fast, the captain decided that a go-around was not possible
and thus cancelled the stability criteria (gate at 1000 feet), their
only option was to put the aircraft down as quickly as possible.
The
first officer described the time between 1800 feet and touchdown as an
eternity, he was however able to recognize that the aircraft had reached
and was maintaining correct approach speed and realized they had not
worked the landing checklist. He thus processed the landing checklist
which required all his efforts, it was difficult to process the
checklist, it was difficult to concentrate and think.
Both pilots reported that just prior to landing they perceived their situation as surreal and like in a dream.
The
aircraft touched down on the runway, the automatic brakes slowed the
aircraft to about 40 knots, the captain subsequently applied manual
brakes, the aircraft began to skid, the captain however managed to slow
the aircraft to taxi speed and vacate the runway via taxiway A3. He then
joined taxiway A and handed controls to the first officer to be able to
talk to emergency services. The first officer totally focussed on
steering the aircraft that he did not get anything that happened around
him.
The captain in the meantime was talking to emergency
services, tower did not want them taxi to the gate but to a remote stand
away from the buildings, following that decision the captain took over
again and taxied the aircraft to the stand. Shortly before arriving on
stand the first officer noticed they had not yet run the after landing
checklist, the checklist was now executed. After reaching the stand and
applying park brake both crew realised the APU had not yet been started,
the APU was started.
The first officer wanted to open his side
window, but needed three attempts to do so. After the window was open he
removed his oxygen masks, but immediately noticed the acrid smell again
and donned his oxygen mask again.
Emergency services
subsequently entered the cockpit, the first officer needed assistance to
get off the aircraft, while the captain remained in the cockpit until
all passengers had disembarked. Emergency services measured oxygen
levels in the blood of both pilots and found the captain substantially
below 80% (at about 70%) and the first officer below 80%, paramedics
commented both pilots were close to faint.
The BFU stated the events in the cockpit remained unnoticed in the cabin until after landing.
Following
landing the aircraft was checked by airline maintenance who identified
de-icing fluid as source of the smell. The technicians reported that
they could clearly detect the odour even 15 minutes after landing.
Maintenance replaced cooling fans for cockpit instrumentation, no
pollution was detected. The engines were checked, washed and ground run
with no findings, the flight crew oxygen supply and masks replaced, and a
45 minutes test flight undertaken with no odours, the aircraft was thus
returned to service on Dec 20th 2010.
A C-Check 13 months later also did not identify any possible causes of the smell.
The
BFU reported that their initial information received from emergency
services had been smoke in the cockpit, both pilots were treated in
ambulances, it was suspected they were suffering from smoke poisoning.
Subsequently the airline told the BFU, that there had been no smoke but
only smell, maintenance had identified de-icing fluid as cause of the
smell, the crew had been released from hospital, the crew did not suffer
from any poisoning. Following that information the BFU decided to not
open an investigation.
Only a year later the BFU received additional information which prompted the BFU to open an investigation.
The
BFU reported that medical services at the airport already measured the
blood oxygen levels of both pilots and found the values below and well
below 80%. Both pilots were subsequently taken to a hospital for further
diagnosis. During the drive to the hospital one pilot recovered to the
point where he commented he could clearly think again. After two hours
in the hospital both pilots were discharged without blood analysis.
The
first officer went to the hospital again the following day for a
detailed analysis of his health condition. A blood analysis detected two
conspicuous values in the area of clinical chemistry, the first officer
was not fit for duty for 6 months.
The BFU did not release any safety recommendations so far.
In
a similiar event involving the very same Germanwings A319 the Irish
AAIU concluded "The probable cause of the adverse symptoms reported by
the aircraft crew and some passengers could not be determined", see Accident: Germanwings A319 at Dublin on May 27th 2008, pressurization problems.
Dec 5th 2013
The German BFU released their final report concluding the probable cause of the accident was:
The
health impairments of both pilots combined with a significant
limitation of the capability to perform which had occurred during the
approach were very likely caused by:
- Massive development of smell in the cockpit area whose origin and spread could not be determined.
Contributing factors could have been:
- Physiological and psychological effects of the smell on both crew members
The BFU added, that no smell was noticed in the cabin.
The
BFU therefore analysed that scenarios like oil leakage in engines, APU
or hydraulic systems, cockpit contamination by TCP, supply of
contaminated air from the outside, contamination with insecticides,
de-icing fluid, use of dry-ice, carbon-monoxide, rain repellent or some
sort of disease were unlikely, stating that scenario involving toxic
substances like tricresylphosphate and its isomers,
n-phenyl-l-naphthylamine and carbon-monoxide had been looked into,
however, with respect to TCP's ortho isomer which might have caused
symptoms similiar to those experienced the BFU stated: "That the TCP
ortho-isomer was present during the approach to Köln/Bonn on 19 December
2010 could not be proven".
The BFU stated however:
"The BFU does not entirely rule out the following scenario:
- Smell development due to malfunctioning electrical or electronical systems on board"
and
stated: "Such a contamination of the air in the cockpit or a local
smell development due to an electrical malfunction could not entirely be
ruled out. The BFU has knowledge of cases in which e.g. a tantalum
capacitor developed an intense smell. It was a temporarily extremely
unpleasant smell which forced the crew to don their oxygen masks.
Determination of the cause was difficult because often these tantalum
capacitors only serve as buffer amplifiers in electrical gadgets. Even
if a component were defective the electronic system would still be fully
functional and it would be very difficult to identify the "burnt"
tantalum capacitor."
The BFU reported that the captain (35, ATPL,
8,535 hours total, 7,864 hours on type) recovered and was fit to fly
after 4 days, the first officer (26, CPL, 720 hours total, 472 hours on
type) needed 6 months to recover and become fit to fly again.
The
BFU complained: "For the BFU it was unusual that about one year later
the severity of the occurrence came to light because of new information
the BFU received" stating a BFU representative had been at the aircraft
25 minutes after the aircraft landed and had talked to the captain, the
captain identified as having been impaired or partially impaired
indicating that he had difficulties controlling the aircraft. The first
officer, who was already in the ambulance, was not interviewed, the
representative not identifying it necessary as treatment in the
ambulance, e.g. to prepare blood samples, was not unusual. As result the
investigation was based only on QAR data and the interviews with the
crew, however, did not have cockpit voice or flight data recordings
available. The BFU summarised: "Due to an error in communication within
the BFU the seriousness of the occurrence had not become clear."
The
BFU analysed that the QAR data did not identify any anomaly in flight
and flight profile except that the speed was too high during intercept
of the glideslope, which however was noticed and the captain made
several inputs to correct. The aircraft and flight trajectory met the
criteria of a stabilized approach. The approach thus was stable and
safe, the aircraft touched down in the required landing configuration
and in the touch down zone of the runway.
The BFU analysed with
respect to human performance: "The only source of information the BFU
had, were the QAR data and the descriptions the two pilots had given,
because neither CVR data, nor video recordings, nor witness reports were
available. The pilots have assessed the severity of their physiological
and psychological limitations with the help of a description and
decision-making aid. The classification the PIC made of "Impairment" to
"Partial Impairment" showed that he could perform his tasks with some,
partially even great difficulties and that he made some minor errors.
One example was that the landing checklist was completed after the pilot
monitoring had reminded them to do so. The co-pilot described the
impairment of his performance capabilities as "Partial Incapacitation"
which means he could carry out his tasks with great difficulties only.
In summary, the BFU has come to the conclusion that neither of the two
pilots suffered "full" incapacitation. However, both were significantly
impaired in their capacity to perform. The co-pilot was more gravely
affected than the PIC. This assessment was confirmed by the analysis of
the course of the flight between the beginning of the occurrence and the
parking of the airplane at the parking position. In spite of severe
limitations the crew was able to bring the flight to an end in a
controlled fashion."
With respect to use of resources and
response to the fumes and recognition of impairment the BFU analysed:
"The decision of the PIC to conduct the approach and landing manually
instead of automated was noteworthy. In general, the automated conduct
of flight is supposed to be a relief for flight crews which should also
be true for abnormal situations. The BFU is of the opinion that an
autoland would have posed risks because the required operating
conditions for the instrument landing system on the ground could not be
guaranteed in the short time available." and concluded: "The BFU does
not question the pilot's decision to fly and land manually after the
occurrence had happened. The justification that the situation had scared
him, and he then rejected the thought to conduct an autoland pretty
fast, because he would have had to consider too many things, was
understandable. When the BFU reviewed the course of action, the argument
and the sense of the PIC that due to his long-term experience the
control of the airplane would occur "automatisiert" (automated) were
taken into consideration. The fact that approach and landing were
stabilised and safe shows that the PIC had estimated his options in this
situation correctly."
Source:
http://avherald.com/h?article=434e753b/0019&opt=0
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