Yesterday I shared the rather insane story of a Singapore Airlines A330 flying from Singapore to Shanghai, which lost power in both engines and descended for 13,000 feet before the pilots managed to restart the engines. This was by no means a “plunge,” but rather a gradual glide, given that planes can glide for quite a distance even without any engine power.
Singapore Airlines #SQ836 lost power on both engines & lost 13,000 feet before power returnedhttp://t.co/l0m3uoLds6 pic.twitter.com/IOjO2FujsN
— Flightradar24 (@flightradar24) May 26, 2015
A double engine failure is exceptionally rare, though perhaps the most shocking part is that the pilots didn’t divert the plane, even though they were near several diversion airports.
So what really happened? The Sydney Morning Herald has a quote from an airline spokesperson about the incident:
“Both engines experienced a temporary loss of power and the pilots followed operational procedures to restore normal operation of the engines,” Singapore Airlines said in a statement.
The airline added that one engine returned to normal operations almost immediately.
The pilots followed operational procedures to restore normal operation of the second engine by putting the aircraft into a controlled descent before climbing again, the airline said.
It doesn’t seem like they’ve figured out what caused the double engine failure, and a further investigation will be done by both Airbus and Rolls-Royce:
The plane landed safety in Shanghai, where no immediate “anomalies” were found in the engine, it added.
Rolls-Royce said it was providing “support and technical assistance” to Singapore Airlines, while Airbus said it was in contact with both the airline and the engine maker to determine the cause of the power loss.
But the part of the story which is truly bizarre is that the plane didn’t divert. On one hand I’m by no means in favor of second guessing pilots’ decisions, since ultimately they’re trained for virtually any kind of situation, and we have to trust they’re acting in everyone’s best interest.
This is a very unique case, though. I just spoke to a friend who’s a “heavy” captain for a major carrier, and asked him if there were any circumstances under which he could imagine not diverting after undergoing a double engine failure. He said no, because in such situations his airline trains pilots to divert as quickly as possible (of course after gaining control of the aircraft, which is the first priority).
There’s also a quote from a “senior captain:”
Pilots told Reuters that losing power in both engines was an extremely rare event, but one that they were trained to handle.
“We do occasionally lose power in one engine for various reasons, but you hardly ever lose both engines. If that happens, you follow the procedures in your check-list and try to restart the engines. The pilots successfully did that here,” said a senior captain with a southeast Asian airline.
“If it was a very serious incident, they would have diverted to Hong Kong. But the fact that they continued on to Shanghai indicates that this may not have been as serious,” the pilot said, declining to be named as he was not authorised to speak to the media.
And while that makes perfect sense, I guess I’m just shocked that there’s a circumstance under which a double engine failure would be considered “not so serious.”
I know I have plenty of airline pilot readers, so rather than me cluelessly speculating, I’d love to hear what you guys have to say. Pilots are understandably opposed to speculating, but I’d ask the same question I asked my “heavy” pilot friend — are there any circumstances under which you could imagine not diverting after undergoing a double engine failure, assuming you have suitable diversion airports?
Interesting stuff, and I’ll be very curious to see what comes of this investigation.
GE is a great company that makes quality products. They are an excellent employer with great leadership.
Exactly why I don’t think GE’s and RR’s F-136 engine should fly. Now that GE is working with P&W, and P&W’s F-135 caught fire right before the Farnborough show, the AETD isn’t in a much better position. The claim in this article about the GE90 engines being different is just as bizarre. The GE90 was certified in 1995 before any analysis was done on the combustor (1996-1997, Don Gardner, 513-243-2000) and in 2000 the GE90-115B...
Exactly why I don’t think GE’s and RR’s F-136 engine should fly. Now that GE is working with P&W, and P&W’s F-135 caught fire right before the Farnborough show, the AETD isn’t in a much better position. The claim in this article about the GE90 engines being different is just as bizarre. The GE90 was certified in 1995 before any analysis was done on the combustor (1996-1997, Don Gardner, 513-243-2000) and in 2000 the GE90-115B engine was certified. The fact that analyses aren’t being done is what is disturbing. Westinghouse was late a year to the NRC with vibrational analysis of 400 new nuclear rods for the AP1000 and Westinghouse wanted to take the “5 week” study down to one week, ie, no study, Frank DeLose, Waltz Mill, PA, and that GE wanted to pull the heat shield out of IHI’s turbine rearframe of the GE90-115B commercial jet engine with a ~5 week aero study only, impossible to get all signatures in 5 weeks. Write your Congressmen and women, all of them.
Exactly why I don't think GE's and RR's F-136 engine should fly. Now that GE is working with P&W, and P&W's F-135 caught fire right before the Farnborough show, the AETD isn't in a much better position. The claim in this article about the GE90 engines being different is just as bizarre. The GE90 was certified in 1995 before any analysis was done on the combustor (1996-1997, Don Gardner, 513-243-2000) and in 2000 the GE90-115B...
Exactly why I don't think GE's and RR's F-136 engine should fly. Now that GE is working with P&W, and P&W's F-135 caught fire right before the Farnborough show, the AETD isn't in a much better position. The claim in this article about the GE90 engines being different is just as bizarre. The GE90 was certified in 1995 before any analysis was done on the combustor (1996-1997, Don Gardner, 513-243-2000) and in 2000 the GE90-115B engine was certified. The fact that analyses aren't being done is what is disturbing. Westinghouse was late a year to the NRC with vibrational analysis of 400 new nuclear rods for the AP1000 and Westinghouse wanted to take the "5 week" study down to one week, ie, no study, Frank DeLose, Waltz Mill, PA, and that GE wanted to pull the heat shield out of IHI's turbine rearframe with a ~5 week aero study, impossible to get all signatures in 5 weeks. Write your Congressmen and women, all of them.
I would have been interested to know if SQ maintenance took a sample of the fuel from the sump after landing in PVG.
Trent engines do not tolerate fuel contamination well. Nit that I personally believe this coild have been the cause of the incident, but it seems like one of the possible angles to check out.
Until SQ (if ever) gives more info on what happened from the Pilots Report it seems futile to...
I would have been interested to know if SQ maintenance took a sample of the fuel from the sump after landing in PVG.
Trent engines do not tolerate fuel contamination well. Nit that I personally believe this coild have been the cause of the incident, but it seems like one of the possible angles to check out.
Until SQ (if ever) gives more info on what happened from the Pilots Report it seems futile to speculate.
Hope we find out more, since this is a major incident, if truly both engines "quit" fully with fuel in the tanks and no leak.
Time will tel..
Lucky, for what its worth, you can count me among those of your readers that absolutely love the trip reports, especially the long haul trip reports. They are my favorite part of the blog. I truly don’t care if it is a product/service you’ve previously reviewed. Every flight is different and I would gladly read about every CX JFK-HKG, or AA ORD-PEK leg you fly. Just 1 guy's opinion.
@ Greg -- Thanks! :)
@Ben - I want to apologize for assuming poor intent on your part. Your heart is in the right place, I know that. This was a reflection of my shit, not yours. :)
Add my 2 more wild guesses:
An "easy" landing at a fair weather airport is probably preferable to risking the chance of having to go around. If there really was a limited power situation, powering out of a missed approach in bad weather might require another change of underwear.
The additional time at cruise was only about 40 minutes before they started down towards PVG. They needed to go through the procedures anyway. Might as...
Add my 2 more wild guesses:
An "easy" landing at a fair weather airport is probably preferable to risking the chance of having to go around. If there really was a limited power situation, powering out of a missed approach in bad weather might require another change of underwear.
The additional time at cruise was only about 40 minutes before they started down towards PVG. They needed to go through the procedures anyway. Might as well keep cruising in the right direction rather than adding more complications. Any why not lighten up by burning off more fuel at cruise (instead of taking time and effort to dump it).
@iv - the Air Transat case was somewhat different in that they hadn't lost power - they had lost (all available) fuel due to a leak and there was no way the engines could be restarted. Gliding was the only way to go ;)
A few years back AirTransat 236 (also flying A330) lost power to both engines over the Atlantic and it glided to a safe landing in Azores.
I really have to echo what some of the others have said here: Lucky, you're not a reporter, nor are you an aviation specialist/expert. You're a travel blogger that focuses on miles and points. Even then there's a fair amount of information published on these blogs that are questionable with regard to impartiality and objectivity. With incidents such as this, it's much better to leave it to someone who's more well-versed and more informed to...
I really have to echo what some of the others have said here: Lucky, you're not a reporter, nor are you an aviation specialist/expert. You're a travel blogger that focuses on miles and points. Even then there's a fair amount of information published on these blogs that are questionable with regard to impartiality and objectivity. With incidents such as this, it's much better to leave it to someone who's more well-versed and more informed to speak/write about it rather than spouting off about some nonsense that you cobbled together in 20 minutes. It does no one any favors and merely spreads misinformation and paranoia.
SQ maintenance control and their dispatch were certainly in the decision making chain here. The pilots have final authority but there is a good possibility they were influenced by folks on the ground. I didn't read everything there is to know about this story but here is an example: Dispatch could see that HKG and other suitable airports in the region were having weather issues so were less than ideal diversion airports (as they're dealing...
SQ maintenance control and their dispatch were certainly in the decision making chain here. The pilots have final authority but there is a good possibility they were influenced by folks on the ground. I didn't read everything there is to know about this story but here is an example: Dispatch could see that HKG and other suitable airports in the region were having weather issues so were less than ideal diversion airports (as they're dealing with other company flights with weather issues in the area). MX control says all indications are now normal, so flying an extra 90 minutes (over land) presents minimal additional risk to the situation. They also have maintenance support staff at Shanghai so that may have led to a preference to continue on. I still think a diversion to the closest suitable airport is probably the best course of action after a dual flame out but there were other factors at play here most likely.
James is right.
Just because an aircraft descends while experiencing a loss of thrust doesn't mean that the descent was done because the aircraft couldn't maintain straight and level. 1% less than the demanded power level is still a loss of thrust.
If I were to guess, and it would be a guess, I'd say that as a result of flying through the thunderstorms in the region the engine inlet probes got covered in ice...
James is right.
Just because an aircraft descends while experiencing a loss of thrust doesn't mean that the descent was done because the aircraft couldn't maintain straight and level. 1% less than the demanded power level is still a loss of thrust.
If I were to guess, and it would be a guess, I'd say that as a result of flying through the thunderstorms in the region the engine inlet probes got covered in ice and sent faulty temperature data to the engine controller. An iced up probe will report something in the region of 0C, at 40,000ft the temperature is typically around -50C this discrepancy will cause the engine to trim the fuel back.
I don't have a copy of the FCOM but it would seem likely that the profile flown was in accordance with the guidance to defrost the probes, once this was done full thrust would once again be available and there would be no need to divert at all.
Go and re-read the statement from Singapore airlines and what they say makes absolute sense. Lucky's comment that, "It doesn’t seem like they’ve figured out what caused the double engine failure" is unhelpful and taints the rest of the article - there was no double engine failure.
@Charles says: Do we reasonably think GE engine is more reliable than RR engine?
I checked some A330 use GE engines.
What information would you have that would support that notion? Or even that it was a reliability issue in the first place? These comments get so silly so quickly...
@Kevin - Even the busiest airport will be able to find a way to prioritize a plane that has had both engines fail. Getting them to a gate would have been another matter, but at least they would have been on the ground safely as soon as possible.
Like other readers have said, perhaps the incident as not as severe as it may seem, but HKG certainly would have been an option.
Do we reasonably think GE engine is more reliable than RR engine?
I checked some A330 use GE engines.
@Ben - Given the fact that you have been critical (more than once) when either non-pilots or anyone without specific facts speculate on airplane incidents, it disappoints me that you end this post asking your readers what they think (when only the pilots can answer this question). I'm beginning to think your post blueprint is to end a post with a question to encourage comments (thus, controversy, thus, traffic). In other words, creating click...
@Ben - Given the fact that you have been critical (more than once) when either non-pilots or anyone without specific facts speculate on airplane incidents, it disappoints me that you end this post asking your readers what they think (when only the pilots can answer this question). I'm beginning to think your post blueprint is to end a post with a question to encourage comments (thus, controversy, thus, traffic). In other words, creating click bait, if you will. Also, you posted yet another 'trip report' of CX first with no real added insight is another indicator that it may be time to rethink your mission for this blog. Or maybe my expectations are too high - or - I've outgrown the blog.
@ Seattle Eric -- Appreciate the feedback, and maybe I didn't phrase it correctly. I said: "I know I have plenty of airline pilot readers, so rather than me cluelessly speculating, I’d love to hear what you guys have to say." The intent was for airline pilots to chime in.
As far as the Cathay Pacific trip report goes, the only reason I wrote that installment was because everything else I was reviewing with the...
@ Seattle Eric -- Appreciate the feedback, and maybe I didn't phrase it correctly. I said: "I know I have plenty of airline pilot readers, so rather than me cluelessly speculating, I’d love to hear what you guys have to say." The intent was for airline pilots to chime in.
As far as the Cathay Pacific trip report goes, the only reason I wrote that installment was because everything else I was reviewing with the trip report was new, including Cathay Pacific business class, the Qantas Lounge Hong Kong, Park Hyatt Maldives, Regal Airport Hotel Hong Kong, etc. I wanted to be as complete as possible, so figured it made sense to write the first installment about my Cathay Pacific flight rather than starting the report in Hong Kong. Seems easy enough to skip if it's not of interest to people.
Lucky: HKG was a zoo the evening of May 23, with a massive storm hovering around the area. There must have been hundreds of planes parked at the airport and most flights were diverted, while those already on the ground were not allowed to take off. Here's one press report: http://www.scmp.com/news/hong-kong/health-environment/article/1807961/more-travel-chaos-expected-hong-kong-airport
I love your blog but your constant harping about landing immediately in HKG probably wouldn't have worked out that night, and might have taken...
Lucky: HKG was a zoo the evening of May 23, with a massive storm hovering around the area. There must have been hundreds of planes parked at the airport and most flights were diverted, while those already on the ground were not allowed to take off. Here's one press report: http://www.scmp.com/news/hong-kong/health-environment/article/1807961/more-travel-chaos-expected-hong-kong-airport
I love your blog but your constant harping about landing immediately in HKG probably wouldn't have worked out that night, and might have taken even more time than just going on to PVG.
It says "loss of power", it doesn't say the engines failed. Likewise, it doesn't say that the descent was due to an inability to maintain altitude.
Not an expert and entirely speculation as to how trivial this incident really could be. Perhaps both engines lost a small percentage of power, one immediately regained correct power levels, and the checklist/procedures state, for whatever reason, that attempts to regain correct power must be done at a particular/lower...
It says "loss of power", it doesn't say the engines failed. Likewise, it doesn't say that the descent was due to an inability to maintain altitude.
Not an expert and entirely speculation as to how trivial this incident really could be. Perhaps both engines lost a small percentage of power, one immediately regained correct power levels, and the checklist/procedures state, for whatever reason, that attempts to regain correct power must be done at a particular/lower altitude? For all we know, these reports could be describing an incident in which one engine was down (say) 5% power for a couple of minutes, and a known (even human) cause was found and corrected.
Lucky
I guess the plots at Singapore do not worry about lawyers first.
Do I hear you worrying about the Singapore F class suites flight you have booked?
If you have enough Dom it will not matter if one engine or both are gone.
I find it amusing that in the previous comment section people were fighting it out over whether or not the pilots should have diverted to HKG—as if the only two choices were a perilous backtracking or risking the lives of all onboard by pressing on—completely ignoring the fact that there were 4 other suitably large airports between Hong Kong and Shanghai to divert to if necessary, with 3 of them even handling international flights. But...
I find it amusing that in the previous comment section people were fighting it out over whether or not the pilots should have diverted to HKG—as if the only two choices were a perilous backtracking or risking the lives of all onboard by pressing on—completely ignoring the fact that there were 4 other suitably large airports between Hong Kong and Shanghai to divert to if necessary, with 3 of them even handling international flights. But at the end of the day, one probably shouldn't expect trip report blog commenters to know that much about geography or aviation.
they were less than 2 hours from final destination and the checklist brought back both engines with no further issues. Diverting from altitude may not have gotten them on the ground a whole lot faster.
Rare, strange incident. We should study the pilots' actions and learn from them. I can't stand when people make it out like they are gods who can't be questioned or analyzed. BUT it must be done in context by professionals,...
they were less than 2 hours from final destination and the checklist brought back both engines with no further issues. Diverting from altitude may not have gotten them on the ground a whole lot faster.
Rare, strange incident. We should study the pilots' actions and learn from them. I can't stand when people make it out like they are gods who can't be questioned or analyzed. BUT it must be done in context by professionals, not by media or enthusiasts whose analysis is ignorant at best and flawed at worst.
No one can drive a car as well as a back seat driver.
"I’m just shocked that there’s a circumstance under which a double engine failure would be considered 'not so serious.'"
I suppose you could say that at FL400 a massive (but temporary) water ingestion event resulting in a dual flameout is substantially less serious than an unrecoverable fuel leak resulting in permanent starvation. That being said it's hard to be certain the threat is fully understood and addressed while you're still up in the air. You...
"I’m just shocked that there’s a circumstance under which a double engine failure would be considered 'not so serious.'"
I suppose you could say that at FL400 a massive (but temporary) water ingestion event resulting in a dual flameout is substantially less serious than an unrecoverable fuel leak resulting in permanent starvation. That being said it's hard to be certain the threat is fully understood and addressed while you're still up in the air. You say pilots don't like to speculate, but that's exactly what appears to have happened here. The pilots speculated that everything was resolved and continued on with the original flight plan.
What's even more interesting is that they checked the engines and had the plane flying again in two hours.
Ben, what if one of the engine failed, and they inadvertently turned off the wrong one when trying to restart it? It's been known to happen before. Then, when they realized what they had done, they restarted the working engine and pressed on...
This is such a weird incident