Motorer skal ikke feile, men de gjør det, også på de lange oversjøiske rutene - AVweb

Undertegnede har ca 50 000 "motortimer" og over 20 000 flytimer. Gjennom årene har jeg sikkerhetslandet tre ganger; to med motorrelaterte problemer, og en gang uten olje på MGB i helikopter. De to første var en T5 motor som driver nozzlene i en F-5 J-85 motor, og en landing med P-3B hvor akslingen til en T-56 motor røk. Jeg har altså aldri opplevet at selve motoren sviktet. Fantastisk. (Red.)


Nothing like a loud bang at 35,000 feet (FL350) .......

........westbound over the North Atlantic in late November to make the sleepiest coach passenger snap both eyes wide. Subsequent bangs from the American Airlines Boeing 777-200's right engine quickly had the cabin crew's attention, and even though the explosions were somewhat muffled forward of the cockpit door, Captain Robert Matthews, 63, also heard it, saw the EPR fall as EGT rose and knew there'd be paperwork. Spoiler alert: This Triple-Seven didn't make it to Miami from Paris as filed, but didn't make the evening news, either. Should have.

Consider how routine it is for thousands of airplanes to cross the U-boat-infested North Atlantic every day without incidents more serious than running out of Prosecco. In the piston-engine days of DC-7s and Connies, the flight engineer, an airborne mechanic, routinely nursed a misbehaving radial, while giving Ernie Gann new material for his next novel. Jet engines provide far less drama, Captain Sully's bird-sucking experience notwithstanding. In Captain Matthew's three-decade AAL career, he never shut a turbine down in flight, and six miles above the ocean isn't the ideal location to learn how to handle losing one, especially when you only have two.

While ETOPS sounds like a supporting monster in Homer's Odyssey, it really means Extended-Range Twin-Engine Operations. Or: Two engines will safely haul hundreds of passengers across the ocean, because jets are so darn reliable, and two are cheaper to run than four. Until they're not, and then the other engine, the one still turning, is expected to take you back to land, although at a lower altitude and slower speed, giving the crew more time to run through pages of emergency checklists, notify ATC and try not to consider how big and cold the ocean below is.

Flying across the Atlantic is common enough but not simple. Domestically, instrument pilots are used to receiving radar service from departure to arrival. But it's hard to construct radar sites on water, so trans-Atlantic crews will hear, "Radar service terminated," as coastal lights fade behind the tail. Non-radar lateral and longitudinal (same altitude) separation standards are huge. Put simply, traffic operating above 28,000 to 43,000 feet enters the North Atlantic Tracks (NAT), which are parallel airways (sorta) 60 miles apart, arcing between North America and Europe.

Generally, westbound traffic takes the northern tracks and eastbounders use the southern routes. Track positions change based on the jetstream and turbulence. Without radar, aircraft fly in-trail 10 minutes apart. Pilots make position reports and arrival estimates for the next two fixes. Controllers receive these reports digitally or via scratchy HF and adjust flows accordingly. It's 1940s ATC procedures augmented with datalink and satnav. Vertical separation is a skinny 1000 feet, so to avoid wake turbulence from a heavy above, lower traffic is permitted to offset one mile from the center of the track.

On Nov. 29, 2018, when American Flight 63 was 650 miles west-northwest of Shannon, Ireland, its right Rolls Royce Trent 892 experienced a compressor stall, a disruption of smooth flow of air through the engine. Not good, but the flight crew, as Captain Matthews said, "Reacted within seconds." The causal factors will be determined months hence, but immediately the crew had to shut down, get down and turn around. Oh, and declare mayday before letting the cabin crew and passengers know what was happening without panicking anyone at 35,000 feet above the North Atlantic. Here's how Matthews put it: "In an emergency, we get task saturated very quickly, even in a minor emergency. The captain has a lot to think about, just the nature of what comes with command. You worry first about safety and resolving the emergency but also legalities, procedures and policies. Not least of these are keeping the flight attendants in the loop and briefing the passengers."

Training is everything. Pilots rehearse this unlikely scenario in recurrent simulator sessions, so when the fit hit the fan blades, the crew reacted as trained with the FO reading checklists while the captain flew the airplane. The Engine Limit, Surge, Stall checklist automatically popped onto the electronic checklist display. Combined with memory items, they secured the failed engine but left it at idle so the engine generators could continue running as well as engine- and pneumatic-driven hydraulic pumps, bleed air and pressurization. All within accepted procedure. But after an hour, the engine over-temped, and they shut it down, although the APU had been fired up to provide electrical power.

Aviate, navigate, communicate. They flew the airplane, and after initial power loss, turned--as procedure demanded--45 degrees from the track and descended, because one engine wasn't going to keep them at FL350. Their choices came down to diverting to Keflavik, Iceland, where weather was awful or back to Shannon, Ireland, where it was better. Turning, they contacted Shanwick, the oceanic controller, announcing--not requesting--that they were heading back. Shanwick knew what to do, and all doors opened for the single-engine Triple Seven now descending to FL210.

Matthews flew the ILS on autopilot but kicked it off at 400 feet AGL to land the half-million-pound B777 by hand, even though it was perfectly capable of autoland. Because he's a pilot, and "The Triple Seven is an awesome airplane," that's why. Brakes smoked a bit after stopping on the 10,000-foot runway, but fire crews declared them safe to taxi, and Matthews did so to the gate.

Full disclosure: I've known Captain Matthews for decades. His wife, Jodi, was my primary student before she met Bob and realized he was a way better pilot with a really cool Stearman biplane. When Jodi informed me of Bob's unsung emergency, I thought, "Who better than Captain Matthews to handle a flame-out over water ... especially since Sully already had his Tom Hanks moment?" And now, the Paul Harvey "Rest of the story."

When things went bang at 35,000 feet, Captain Matthews was three weeks from retirement. He'd made over 900 trans-Atlantic crossings in his 20 years flying international, which, besides Europe, included South America, polar flights to Asia and even Moscow. This flight was supposed to have been his penultimate crossing before hanging it up, but when asked what he wanted after landing at Shannon, Matthews replied, "to retire."

Wasn't to be. American Airlines offered to let Captain Matthews fly his final trip from Ireland to Miami. He accepted, and the next day--with fire trucks arcing water cannon streams over the replacement Triple Seven--Captain Matthews pulled up to the gate, where below on the ramp, wearing a yellow ramp rat vest, stood (danced) Jodi, who just may have pulled off the best retirement homecoming ever, as a 40-year aviation career wound down with a healthy turbine whine and not a bang.