Irrational: I avoid 2-engine 777 transpacific
#20
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Originally Posted by Braniff
...so I'm afraid of breaking my irrational policies. 

.
#23
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I'm no aviation expert, but if I recall one engine on the 777 can fully power and fly a 747, If I remember they actually tested this and had a 747 flying with one 777 engine.
#24
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Given the normally overwater usage, I've heard it as
Engines
Turn
Or
Passengers
Swim
Anyway, I don't know of any all engines out failure on a twin that would have been helped by an extra engine or two. You don't get a failure of two. You get either one, or all regardless of the number. (However, there have been 747 engine failures where one engine took out the adjacent engine on the wing.)
The all engines out scenario is usually lack of fuel. Other than that, there's been cases of water or volcanic ash ingestion. There was also a Tristar that had the same faulty maintenance done on all three engines (missing O rings) that caused all three to fail.
The other thing to consider is that non-ETOPS jets can still go up to 60 minutes from an airport. Having both engines go out when you're an hour from a runway is no fun either.
Engines
Turn
Or
Passengers
Swim
Anyway, I don't know of any all engines out failure on a twin that would have been helped by an extra engine or two. You don't get a failure of two. You get either one, or all regardless of the number. (However, there have been 747 engine failures where one engine took out the adjacent engine on the wing.)
The all engines out scenario is usually lack of fuel. Other than that, there's been cases of water or volcanic ash ingestion. There was also a Tristar that had the same faulty maintenance done on all three engines (missing O rings) that caused all three to fail.
The other thing to consider is that non-ETOPS jets can still go up to 60 minutes from an airport. Having both engines go out when you're an hour from a runway is no fun either.
#25
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Originally Posted by zoonil
I guess a lot of people are thinking four engines are better than two! Why else will Virgin Atlantic paint all their planes with "four engines for the altantic" or something similar to that ( I don't remember the exact phrase)
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#26




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Originally Posted by railroadtycoon
I'm no aviation expert, but if I recall one engine on the 777 can fully power and fly a 747, If I remember they actually tested this and had a 747 flying with one 777 engine.
Per Wikipedia (http://en.wikipedia.org/wiki/ETOPS):
In the North Pacific, ETOPS-180 (180 minutes) is satisfied by the availability of airports in the Aleutians Islands and Midway Atoll. As the Aleutians airports are prone to adverse weather conditions and volcanic activities, Boeing subsidised construction of the Midway Atoll diversion airport to enable the 777 to fly the North Pacific routes. After a petition from Boeing and United Airlines, in 2001, the FAA allowed a 15% extension to the ETOPS-180 rules bringing them to ETOPS-207. The approval is granted only to the 777. This approval is granted only if Northern Pacific route diversion airports are closed.
Last edited by globetrekker84; Nov 1, 2006 at 6:54 pm
#27




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Originally Posted by og
The words were "four engines for long haul". But that is no longer the case. The VS 346s that visit SYD have had the slogan removed. IIRC, VS are now buying 2 engine long haul aircraft.
http://www.airliners.net/open.file/1124431/L/
Too bad they're getting rid of the slogans with the new livery. Always liked "Mine's bigger than yours."
Can you provide a link regarding your statement that VS is going to buy 2-engined aircrafts? Because I sure haven't seen or heard of anything (other than those nuts at a.net).
#28
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Originally Posted by globetrekker84
Oh yeah. The engines on the T7s are insanely powerful, especially the newer General Electric GE90-110B1 (110,000 lbf thrust), and insanely huge - the diameter of the engine is bigger than the cabin of a 737.
#29




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Originally Posted by alanh
Anyway, I don't know of any all engines out failure on a twin that would have been helped by an extra engine or two.
4 March 2001; United Air Lines 767; near Kona, HI: While early reports indicated that this 767 had a complete loss of power in both engines, the analysis of the flight data recorder by the NTSB does not support this conclusion. According to early FAA and media reports, United Flight 42 took off from Kahului on the Hawaiian island of Maui on a flight to Los Angeles and experienced a dual-engine shutdown about 70 miles (112 km) into the flight, followed by an in-flight restart and a diversion to the Kona airport. Later analysis of the flight data recorder by the NTSB showed that both engines had a reduction of power to below idle, but did not show any evidence of a complete loss of power in either engine. However, there was roughly a 30-second gap in the data during the time when the engines were operating at reduced power. The aircraft, registration number N666UA, has since been returned to service.
Other 767 aircraft have experienced dual engine shutdowns on at least five other occasions:
23 July 1983; Air Canada 767; near Gimli, Manitoba: The aircraft ran out of fuel after the crew miscalculated the weight of fuel on board. The aircraft made an emergency landing on an abandoned airfield. There were no serious injuries.
19 August 1983; United Air Lines 767-200; near Denver, CO: Fuel contamination led to a dual-engine shutdown at about 41,000 feet. The crew restarted the engines at about 15,000 feet.
31 March 1986; United Air Lines 767-200; San Francisco, CA: The engines were inadvertently deactivated the engines during climb at about 3,000 feet. The crew was able to restart the engines and returned to the departure airport.
30 June 1987; Delta Air Lines 767-200; Los Angeles, CA: The engines were inadvertently shut off during climb at about 2,000 feet. The crew was able to restart the engines at about 500 feet and continued to their original destination of Cincinnati.
23 November 1996; Ethiopian Airlines 767-200ER; near Moroni, Comoros Islands: The aircraft was on a flight from Ethiopia to Kenya when it was hijacked. The hijackers refused to allow the aircraft to refuel, leading to a dual engine shutdown due to fuel exhaustion. Ten of the 12 crew members and 117 of the 160 passengers were killed during a subsequent ditching. The three hijackers apparently died.
#30
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Originally Posted by Braniff
Statistically, that would make it dangerous to fly one now. 

Pardon my ignorance, but with a 3 or 4 engine plane, how many engines does the plane need to remain in flight? N-1? or fewer? It's been a while since I did Stats, but I'm pretty sure a 4 engine plane is more likely to lose 1 engine than a 2 engine plane, no?



