Much More
Than Losing an Engine Involved in Extended Range Twin-Engine Flights "The water
looked so cold," one captain confesses... Air Safety Week, Jul.5, 1999
The decision whether or not to
expand engine-out diversion times to 207 minutes now rests with the Federal Aviation
Administration (FAA). Approval to expand extended twin-engine operations (ETOPS) from the
current 180 minute engine-out limitation to 207 minutes will allow the B777 to fly certain
trans-Pacific routes. What's next? Perhaps a request to allow a 234 minute diversion on
one engine to open a route from South Africa to Australia.
The comments in the FAA docket on
the proposed 207 minute diversion time focused largely on reliabilities and probabilities
(see ASW, June 21). We present below perspectives on ETOPS from the cockpit, based on real
in-flight situations. They were gleaned from the Aviation Safety Reporting System (ASRS).
To be sure, these are anecdotal reports, reflecting perhaps the few times out of thousands
of ETOPS flights where problems occurred, but the issues the reports raise seem worth
noting, if nothing else as indicators of the rich variety of things that potentially can
go wrong. Among the items in these reports: the allegation that pilots are under pressure
not to shut down their engines in order to retain ETOPS certification (and possibly
biasing the comforting low in-flight shutdown rates), the utility of satellite telephones
to solve problems (although the phones are not required for ETOPS flights), aircraft
departing without the required ETOPS inspection because of a last-minute aircraft switch
and, above all,
the capacity of aircrews for
intelligent improvisation in the face of surprising circumstances not part of the usual
discussions about ETOPS.
Since the ASRS data base relies on
voluntary confidential reports, it represents a lower number than the actual number of
events which are occurring. This statistical limitation is further compounded by the
belief of some that reports should not be filed under the ETOPS category unless the
airplane experiences a problem within the window of its divert flight time (e.g., 120
minutes, 180 minutes, etc.). This interpretation may be subject to challenge on the
grounds that a problem 5 minutes out of that window could be significant for ETOPS
reporting purposes. In fact, a pilot who experienced a compressor stall during takeoff
reported it as an ETOPS-related event.
Having noted these points, the real
value of ASRS lies in the vivid power of its narrative reports. Herewith, extracts: Human
error:
* B767-300: When we were well into
the transatlantic crossing, the captain informed me that he had checked the minimum
equipment list (MEL) and discovered that all igniters are required for ETOPS...we
understood from our previous reading of the MEL that flight was permitted with one igniter
inoperative. En route to O'Hare we discussed the problem further and consulted the MEL,
which states all 4 igniters shall be operative for all international flights. Why we
failed to check the MEL on the ground I will never under-stand, but it is something I will
always do in the future. Equipment failures
* A300: At almost top of climb,
engine advisory came on and indicated overheated #2. Returned to San Juan. Upon
inspection, maintenance found reverse bleed line, a 1 - inch pipe, cracked and burnt and
melted in many places. Also could not get APU bleed operating in (the) air to supplement
air for packs, if needed. Bleed would not work on the ground, either. No emergency was
declared as situation was contained by turning all air sources off and out of
engine...never did get any bleed light warnings.
* B757: During climbout the #2
engine bleed overheated...so we could not continue on our ETOPS flight and returned to JFK
and made an overweight landing, which is no problem in itself...as this aircraft has no
fuel dump system. However, would have had marginal performance in the event of an engine
loss and a missed approach.
* B757: Caution light came on...In
an attempt to regain the airspeed bug and autothrottle he (first officer) inadvertently
and unknowingly pulled circuit breakers labeled 'spd card' at which time the ram air
turbine deployed. With increased drag and only rough fuel estimate of 7,000 lbs. over
destination, I declared fuel emergency and was given direct route to Newark International
(EWR)...the circuit breaker pulled simulates a hydraulic failure, so the ram air turbine
extended. Once extended, it cannot be retracted until on the ground....These circuit
breakers should be labeled, 'Will cause irreversible ram air turbine deployment. The worth
of satellite radiotelephones
* B767-300: Flight attendants
reported an oven fire in mid cabin galley. They had already extinguished it with halon.
The crew conferred with our company dispatch, maintenance and safety personnel via satcom.
We verified the fire was out and depowered the entire galley and the flight continued
without further incident. Two things stand out to be as being beneficial to the successful
handling of the fire: 1) our company's commitment to putting satellite communications on
our overwater planes. It provided instant, continuous communications with ground
resources. 2) Our crew resource management (CRM) with flight attendants improved our
ability to communicate and bring the entire crew together as a team. The reporter was the
relief pilot riding in the first class cabin when the fire was discovered. The reporter
said the cause was an accumulation of debris, food wrappers, food remains and dirt pulled
into the fan, stalling and overheating (it) and ultimately burning the debris. The
reporter stated the oven fan cir
cuit breaker did not trip.
* B767: In the dead center of the
Atlantic...we noticed an electrical smell in the cabin. Quickly isolated it to seats 3A/B
and shortly thereafter saw smoke from the 3A/B center console. Smoke from a known
source...that has no mention in our manuals. No switches to turn off. No circuit breakers
outside of the E/E (electronics and equipment) compartment and no procedure to solve...via
satcom link...we were able to cut electric power to seats 3A/B by using a Phillips
screwdriver to remove a cover under the seats and dis-connect a cannon plug. Problem
solved. Resources we could have used besides the luck of having satcom would have been
accessible switches or C/B's to deactivate all or parts of the entertainment system. A
clearly marked cover under the seat that could be removed without tools to access the
canon plug and some information to help us cope with ever more complex cabin electronics.
While the broad axe solution of cutting utility power probably would have been enough by
itself, we can do better than
that with a little effort,
information and training. A pilot offers "some human factor thoughts"
* B767-200: This was my second
inflight diversion in just over 1 month for smoke in the cockpit. Last time we were 50
miles from Chatham, Alaska (CYM). Things happened fast. We were on the ground in 14
minutes. This time it was just over 1 hour. It is very stressful with some denial thrown
in. Some procedures are questioned or not completed in entirety (descent to 10,000 ft. on
smoke removal checklist). It is just not as smooth as in the simulator. We never thought
about the possibility of ditching except at one point when passing near the island of
Flores we asked about the airport there (4,800 ft. strip)...We would try that before
putting it in the water. The lead cabin attendant never came up (to go) over his checklist
with the captain. Another pilot offers the ultimate human factors thought
* B767-200: Approaching 42N50W we
noticed the left engine oil quantity decreasing...We declared an emergency and received a
clearance back to New York...an uneventful landing was made...the engine should have been
shut down (in flight). However, there is considerable pressure to keep them running to
maintain ETOPS certification. Also, our POM (pilots operation manual) is not real clear on
what colla-borating evidence is if we get a low oil pressure indication. Is low oil
quantity sufficient or should we wait for a rise in oil temperature? I also had 'the
runway is close' syndrome, and my first officer counseled me not to shut it down. I should
have shut it down. Did I error? (sic) Yeah. I should have shut it down. But the water
looked so cold.
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