Much More Than Losing an Engine Involved in Extended Range Twin-Engine Flights "The water looked so cold," one captain confesses

Air Safety Week, July 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 circuit breaker did not trip.