Swiss A333 at Zurich on Nov 26th 2015, hydraulic leak, first officer and flight attendant feel ill as result

Last Update: November 22, 2016 / 17:14:07 GMT/Zulu time

Bookmark this article
Incident Facts

Date of incident
Nov 26, 2015

Classification
Incident

Airline
Swiss International Airlines

Flight number
LX-18

Departure
Zurich, Switzerland

Destination
Newark, United States

Aircraft Registration
HB-JHC

Aircraft Type
Airbus A330-300

ICAO Type Designator
A333

A Swiss International Airlines Airbus A330-300, registration HB-JHC performing flight LX-18 from Zurich (Switzerland) to Newark,NJ (USA) with 203 passengers and 12 crew, was climbing through FL090 out of Zurich's runway 16 when the crew declared PAN PAN PAN reporting a hydraulic failure. The crew initially requested to maintain FL080, they were currently clear of cloud, but then reported they were back in cloud and requested to continue climb to FL120 to remain clear of cloud. The aircraft entered a hold at FL120 while the crew worked the related checklists and to burn off fuel. The first officer donned his oxygen mask after odour of hydraulic fluid became noticeable on the flight deck and the first officer started to suffer from headache. The aircraft returned to Zurich for a safe landing on runway 16, stopped on the runway for checks by emergency services for brakes temperatures and state of tyres and was finally towed off the runway. A flight attendant suffered from dizziness and nausea the following day with no medical findings.

A passenger reported the crew announced they had lost a hydraulic system at about 9000 feet climbing out of Zurich, they needed to burn off fuel as no fuel dump was available, and returned to Zurich for a normal weight landing. The aircraft was disabled on the runway and was towed off the runway.

On Dec 7th 2015 the Swiss SUST reported, that the crew decided to return to Zurich due to lack of hydraulic fluid. The aircraft received damage to its hydraulic pumps. The SUST rated the occurrence a serious incident and opened an investigation.

On Nov 22nd 2016 the SUST released their summary report in German reporting that the captain (48, ATPL, 11,378 hours total, 369 hours on type) was pilot monitoring, the first officer (34, ATPL, 2,022 hours total, 224 hours on type) was pilot flying. The crew received indication "HYD G LEAK" about 5 minutes after takeoff when the flaps were to be retraced one step. The message was confirmed via the HYD ECAM screen, the crew stopped the climb and requested to enter a hold to work the checklists. More messages including "HYD G RSVR LO LVL" and "HYD G ENG 1 + 2 PUMP LO PR" occurred. An odour of hydraulic fluid was noticed on the flight deck, the first officer started to suffer from headache and donned his oxygen mask. A number of passengers and cabin crew also started to suffer from nausea and headaches.

The crew re-arranged the bleed air supply to the air conditioning systems from the engines to the APU. The intensity of the odour began to decrease afterwards.

The crew discussed the advantages and disadvantes of an overweight landing with the prospect of possibly toxic hydraulic fumes in the cabin and cockpit and consulted with dispatch. Maintenance suggested that no major maintenance action would be necessary if touchdown occured at less than 360fpm. A reduction to the MLW (187 tons) would have meant 3.5 hours burn off time. The crew therefore decided to burn off to 205 tons, which required a landing distance of 2700 meters, chose runway 16 for the return, the captain took control of the aircraft. The aircraft positioned for an ILS approach to runway 16 and touched down at less than 300 fpm, rolled out and stopped about abeam taxiway E7. The brakes temperatures increased and reached the maximum 425 degrees C about 10 minutes after touch down. The aircraft was towed to the gate, where passengers disembarked normally.

The following day each member of the crew was phoned, all but one flight attendant reported on health issue, one flight attendant however reported suffering from dizziness, nausea, difficulties with memory and concentration as well as difficulties with senses of taste and smell. The flight attendant underwent medical examination with no findings.

The SUST reported that a largely unexplored illness is known since 1950, this illness became known as "Aerotoxic syndrome" in 1999. The illness is related to contamination of cabin air. It is possible even in normal operation, that small quantities of toxic parts of operating fluids could be released, evaporate by the hot engines and enter the cabin unfiltered via the bleed air system, in case of leaking seals even large quantities of such toxic parts could enter the cabin that way. The EASA has ordered the University of Hannover and the Frauenhofer Institute to conduct research on that topic, results were not expected before October 2016.

The SUST mentioned specifically that in case of a leak of the used hydraulic fluid the instructions with the hydraulic fluid warn of irritation of respiratory tract, dizziness, nausea and/or loss of consciousness in case of inhaling vapors, especially if beyond the short term limits.

The cause of the leak was determined to be either hydraulic pump 1 or hydraulic pump 2, both pumps were replaced, no further issues were encountered afterwards. The pumps were further examined and, following the 34,000 operating hours, were found with increased seizure of the rotating parts and degradation of the piston shoes.

The SUST concluded that most likely pump 1 suffered internal damage while running under takeoff power due to previous degradation of the piston shoes, which led to a leak of hydraulic leak. Both pumps subsequently began to run dry under the load of retracting gear and retracting flaps until pump 2 became damaged as well due to lack of lubrication and cooling.

The SUST analysed that the decision to land above maximum landing weight was appropriate and prevented the occupants of the aircraft from being explosed longer than necessary to the hydraulic fumes. The symptoms decribed by the first officer in flight and the flight attendant the day after are conceivable even without pathological results - best results would have been possible had blood samples been taken shortly after landing back.
Aircraft Registration Data
Registration mark
HB-JHC
Country of Registration
Switzerland
Date of Registration
Ac dgjejeddAf Subscribe to unlock
Certification Basis
Ik ejh Subscribe to unlock
Airworthyness Category
Ki kjpgi qiclcql Subscribe to unlock
Legal Basis
Qjlg Subscribe to unlock
TCDS Ident. No.
DpmkhgdcAm Subscribe to unlock
Manufacturer
AIRBUS S.A.S.
Aircraft Model / Type
A330-343
ICAO Aircraft Type
A333
Year of Manufacture
Iljg Subscribe to unlock
Serial Number
Gpfp Subscribe to unlock
Aircraft Address / Mode S Code (HEX)
Pfjcnj Subscribe to unlock
Max. Operational Passenger Seating Capacity (MOPSC), indicative
Ged Subscribe to unlock
Minimum Crew
F Subscribe to unlock
Maximum Take off Mass (MTOM) [kg]
Adi eh Subscribe to unlock
Engine Count
A Subscribe to unlock
Engine
ckeehepcdn fbgnnjngpqAghbhgminbnif Subscribe to unlock
Main Owner
L Subscribe to unlock
Main Operator
AgbncqmipeficbAhincqqcb hh ikAdj fj nAgdgbcjibebAbe glnggknmjbnjqAgljmiAdginbjkmlf Subscribe to unlock
Incident Facts

Date of incident
Nov 26, 2015

Classification
Incident

Airline
Swiss International Airlines

Flight number
LX-18

Departure
Zurich, Switzerland

Destination
Newark, United States

Aircraft Registration
HB-JHC

Aircraft Type
Airbus A330-300

ICAO Type Designator
A333

This article is published under license from Avherald.com. © of text by Avherald.com.
Article source

You can read 2 more free articles without a subscription.

Subscribe now and continue reading without any limits!

Subscribe now
Are you a subscriber? Login
Subscribe

Read unlimited articles and receive our daily update briefing. Gain better insights into what is happening in commercial aviation safety.

Compare our plans

Send tip

Support AeroInside by sending a small tip amount.

Send tip

Related articles

Newest articles

Subscribe today

Are you researching aviation incidents? Get access to AeroInside Insights, unlimited read access and receive the daily newsletter.

Pick your plan and subscribe

Partner

ELITE Logo

ELITE Simulation Solutions is a leading global provider of Flight Simulation Training Devices, IFR training software as well as flight controls and related services. Find out more.

SafetyScan Pro

SafetyScan Pro provides streamlined access to thousands of aviation accident reports. Tailored for your safety management efforts. Book your demo today

AeroInside Blog
Popular aircraft
Airbus A320
Boeing 737-800
Boeing 737-800 MAX
Popular airlines
American Airlines
United
Delta
Air Canada
Lufthansa
British Airways