Air Asia Flight D7237 was forced to turn back to Perth from  "technical issue" - Page 1
Forum section: electronics / general

author: Homer J Simpson
author_rank: Super Contributor
timestamp: June 25, 2017, 06:41:07 pm
content: http://www.bbc.com/news/world-australia-40396554

author: Gyro
author_rank: Super Contributor
timestamp: June 25, 2017, 06:44:58 pm
content: QuoteThat sounds exciting!

author: boffin
author_rank: Unknown
timestamp: June 25, 2017, 06:57:07 pm
content: "Air Asia X" not "Air Asia" (technically different companies)I'm quite surprised with a catastrophic engine failure that they didn't divert to the much much closer RAAF Learmonth's long runway (3000+m), vs turning around and flying for another 2 hours back to Perth. Most airlines have a policy for "nearest suitable airport" for this kind of failure.http://flightaware.com/live/flight/XAX237/history/20170624/2250Z/YPPH/WMKKFrom the Wikipedia page forhttps://en.wikipedia.org/wiki/RAAF_Learmonth,it's actually not unusual for a divertOn 7 October 2008, Qantas Flight 72 made an emergency landing at RAAF Learmonth.On 1 June 2012, an AirAsia X flight to Perth made an emergency landing at RAAF Learmonth for fuel refilling.Learmonth is designated an emergency alternative airport in the case of fog or bad weather affecting Perth Airport.An AirAsia X Airbus A330-300, registration 9M-XXE performing flight D7-237 from Perth,WA (Australia) to Kuala Lumpur (Malaysia) with 359 people on board, was enroute at FL380 about 200nm southsouthwest of Learmonth,WA (Australia) when the left hand engine (Trent 772) suffered a blade fracture, ingested the blade resulting in severe damage in engine core and severe vibrations. The crew shut the engine down, drifted the aircraft down to FL200 and returned to Perth for a safe landing about 2 hours after the engine failure.Passengers reported a large bang was heard followed by severe vibrations and sounds like a spinning washing machine. They were instructed to brace for landing.Australia's emergency services reported they put their marine emergency services on stand by for a possible water landing of the aircraft north of Perth.The airline reported the aircraft returned to Perth due to a technical problem without confirming an engine issue. Emergency services were called as precaution only as part of the standard operating procedures. The passengers were rebooked onto other flights.http://avherald.com/h?article=4aac9f14&opt=0

author: Homer J Simpson
author_rank: Super Contributor
timestamp: June 25, 2017, 07:01:00 pm
content: Odd to leave that engine running ?What is the failure mode on an "engine seizure"?Can A330 fly with one ? I would think so for water certification.

author: Wytnucls
author_rank: Super Contributor
timestamp: June 25, 2017, 07:16:55 pm
content: Engine fan was wind milling, not seized. Aircraft may have flown at high speed too.

author: Avacee
author_rank: Unknown
timestamp: June 25, 2017, 08:29:07 pm
content: Quote from: Homer J Simpson on June 25, 2017, 07:01:00 pmA330 is certified for ETOPS-240 since Nov 2009, coincidentally the same month the aircraft concerned (9M-XXE) entered service.https://en.wikipedia.org/wiki/ETOPSQuote from: Wytnucls on June 25, 2017, 07:16:55 pmPlayback of the flight is available athttps://www.flightradar24.com/data/flights/d7237/#dda2d15You can see it descends to 24,000ft, later 20,000 and maintains airspeed.

author: Wytnucls
author_rank: Super Contributor
timestamp: June 25, 2017, 09:06:23 pm
content: Like Boffin said, it is surprising the flight didn't divert to Learmonth.

author: sleemanj
author_rank: Super Contributor
timestamp: June 26, 2017, 02:25:07 am
content: QuoteIt certainly was shaking pretty good going from that video, but unfortunately that's not the only factor in deciding where to go.A landing at Learmonth would make life much more difficult for everybody involved, it's not a simple fuel up and away you go job as it would be for a low fuel emergency, it's an engine replacement for a start and full airframe inspection I would expect having been subjected to that sort of vibration stress, the plane is not going anywhere for quite some time I expect. You also have to get the passengers sorted out, get a replacement aircraft to Learmonth to replane them, or some alternative means to Perth, accommodation, they are probably going to have to re-enter and exit Australia customs whatever the case which might be a problem at an RAAF base...

author: boffin
author_rank: Unknown
timestamp: June 26, 2017, 02:56:39 am
content: Quote from: sleemanj on June 26, 2017, 02:25:07 amActually the SOP for most airlines (and aircraft) for "one engine loss on a twin-engined aircraft" would say "land immediately at nearest suitable airport". Learmonth is certainly "suitable", with a 3000+m runway; existing commercial aviation facilities (although not large). Making it convenient for the owner of the aircraft shouldn't come into it.For this reason, there's actually quite a few diversions to CYFB (Iqaluit, Canada), despite being near nothing.

author: sleemanj
author_rank: Super Contributor
timestamp: June 26, 2017, 03:05:47 am
content: Quote from: boffin on June 26, 2017, 02:56:39 amAir Asia X is a very budget airline.

author: sleemanj
author_rank: Super Contributor
timestamp: June 26, 2017, 05:06:35 am
content: Quote from: blueskull on June 26, 2017, 03:54:18 amPutting aside that you also are confusing Sydney with Perth (those two cities are about 4000 kilometers apart, further than Beijing to New Delhi), aviation is a tough cut throat business, pilots are quietly under pressure from company all the time, especially in the budget sector of the industry.As you say yourself, factors like "home airline engineer" absolutely do factor into diversions where possible, and that's not a safety consideration, it's a financial/convenience/company one.At the end of the day, there will be an investigation and report on the incident, which will certainly include analysis of the pilot's decision to return to Perth instead of other options.Image from PPRUNE thread (unauthenticated as to if it's actually from this incident).http://www.pprune.org/australia-new-zealand-pacific/596307-merged-air-asia-turnback-perth-25-jun-17-a-5.html

author: boffin
author_rank: Unknown
timestamp: June 26, 2017, 06:22:02 am
content: There will be an investigation, and I'm pretty sure 2 years from now when it comes out, you'll read that the Australian Transport Safety Bureau will report negatively on the pilot/company's decision to discount Learmonth, and instead head all the way back to Perth.

author: noidea
author_rank: Unknown
timestamp: June 26, 2017, 06:57:40 am
content: Quote from: sleemanj on June 26, 2017, 02:25:07 amI was working at Learmonth a couple of weeks ago, there is a small terminal building on the Gulf (East) side of the landing strip and the RAAF base is on the West side of the strip. The RAAF base is a "bare base" so whilst there is a massive airstrip and lots of dispersal areas for military aircraft there is not much else around and a handful of people on site, Wikipedia sums it up nicely:https://en.wikipedia.org/wiki/RAAF_bare_basesA big factor in their decision making may have been that there are no ARFF facilities available at the airport, they are only brought in by the RAAF when the base is made operational.

author: EEVblog
author_rank: Unknown
timestamp: June 26, 2017, 07:21:43 am
content: Quote from: blueskull on June 26, 2017, 03:54:18 amSure, buttwo hoursextra flight time with that vibration?Would seem like a no-brainer to me, get it on the ground ASAP.

author: German_EE
author_rank: Super Contributor
timestamp: June 26, 2017, 08:27:14 am
content: Another possible solution to the vibration problem would be to break off a turbine blade at the other side of the fan, thereby restoring the balance***.Finding a hacksaw and a volunteer to go out on the wing might be a problem though.EDIT:*** Yes, I am joking.

author: Avacee
author_rank: Unknown
timestamp: June 26, 2017, 09:21:11 am
content: Quote from: German_EE on June 26, 2017, 08:27:14 amIt has happened....https://en.wikipedia.org/wiki/Norman_Cyril_JacksonThis chap earned the Victoria Cross (highest award for gallantry) for going out onto the wing of a Lancaster bomber with a fire extinguisher to fight a fuel tank fire.

author: gamalot
author_rank: Super Contributor
timestamp: June 26, 2017, 09:21:48 am
content: Tractors, oh tractors, there are so much funTractors, oh tractors, they get the job doneTractors work all day, tractors work all nightGot to bale the hay, got to bale it tight

author: SkyMaster
author_rank: Frequent Contributor
timestamp: June 28, 2017, 12:04:17 am
content: The worst part could be the captain admitting that he was scared and asking the passengers to pray.

author: Bud
author_rank: Super Contributor
timestamp: June 28, 2017, 12:44:09 am
content: Was it the same plane a Chinese grandma tossed some coins into the jet engine for good luck?EDIT: added a linkhttp://www.abc.net.au/news/2017-06-28/elderly-woman-throws-coins-into-plane-engine-causes-delay/8658654

author: IanB
author_rank: Super Contributor
timestamp: June 28, 2017, 12:56:57 am
content: Quote from: EEVblog on June 26, 2017, 07:21:43 amIt doesn't seem the vibration was much different than some air turbulence.Airlines really do have to consider what will happen after the plane puts down. There were over 300 passengers on board; there need to be facilities on the ground to look after them (food, lodgings, people, etc.), a way to evacuate the passengers and get them on their way, and facilities to repair the airplane and get it back in the air.All of these things affect a decision about where to divert to. Given that such aircraft are fully certified to fly with one engine and that this was not a life threatening emergency, the captain probably made an appropriate decision by the book.

author: SkyMaster
author_rank: Frequent Contributor
timestamp: June 28, 2017, 02:08:44 am
content: Quote from: IanB on June 28, 2017, 12:56:57 amWhat do you mean by "such aircraft are fully certified to fly with one engine"? Following an engine failure, or engine shut down, the Airbus A330 has to land at the nearest suitable airport.An engine failure on a twin engine aircraft is an emergency. The aircraft performance is highly degraded on one engine.In today's world, the crew will contact the airline while still in the air. The airline will try to convince the captain to fly to an airport deserved by the airline, exactly for the reasons you gave. But if this turn out to be a bad decision; the captain will blamed.At a small airline I flew for, there was a crew that had to face a cabin smoke/fire. The crew was able to put the smoke/fire out. They overflew a small town airport with no facilities and decided to continue to the main base, which was about 10 minutes away. The plane landed uneventfully. The captain was blamed (by the airline) of having placed the passengers in danger and was downgraded to first officer.The choice of the nearest suitable airport should not be influenced by the passengers comfort once on the ground, or access to repair facilities. "suitable airport" is in reference to the aircraft capabilities and pilots workload; it is easier to make an approach to a runway when you have local knowledge of this particular airport. Of course, the type of emergency would play a big role in the decision.Should a Boeing 747 continues to fly after an engine failure? The story of British Airways flight 268:https://en.wikipedia.org/wiki/British_Airways_Flight_268

author: IanB
author_rank: Super Contributor
timestamp: June 28, 2017, 02:34:19 am
content: Quote from: SkyMaster on June 28, 2017, 02:08:44 amOh, then I stand corrected. Perhaps I should have said "fully able to fly with one engine".If an engine failure on a twin engine aircraft is an emergency, what should we call an engine failure on a single engine aircraft?

author: SkyMaster
author_rank: Frequent Contributor
timestamp: June 28, 2017, 02:57:30 am
content: Quote from: IanB on June 28, 2017, 02:34:19 amTwin engine airliners do not have two engines for redundancy; they have two engines out of necessity.In North America (in Canada at least), there are only two single engine aircraft that I know of that can legally carry passengers in commercial operation (Air Taxi type of operation); the Pilatus PC-12 and the Cessna Caravan. And this is because they both fly behind the very reliable Pratt & Whitney PT-6.In a perfect world, all single engine aircraft pilots would take into consideration the possibility of engine failure when they plan their route.

author: SkyMaster
author_rank: Frequent Contributor
timestamp: June 28, 2017, 03:03:14 am
content: Quote from: blueskull on June 28, 2017, 02:38:53 amB767 and A330 were both glided, to successful landings; by Canadian crews

author: Brumby
author_rank: Unknown
timestamp: June 28, 2017, 03:12:26 am
content: Quote from: IanB on June 28, 2017, 02:34:19 amMany years ago, I was privileged to be part of a group that was given a ground tour of a 747. After walking past a 707, this thing looked HUGE ... and so did the engines.Inside, we had a ground engineer escort us around and I had an opportunity to sit in the co-pilot's seat - and under the direction of the engineer, pushed some buttons! One of those brought up a display showing the air pressure in every one of the tyres. Very cool.We then talked about the engines - and we were told that the 747 only needs the four engines to take off. So, yeah, it needs 4 engines. A fully laden Jumbo can fly and land on 2 - and an empty one on a single engine. So having these capabilities and knowing about them is essential in being able to assess a course of action in an emergency. They are not something you should plan on.I asked what happens if, say, two engines failed on the same side of the aircraft - obviously curious on the resulting yaw moment. The reply came: "That's when the pilots earn their money".It would seem very clear designing such capabilities into aircraft - especially passenger carrying commercial aircraft - has been around for a very long time. Further, inasmuch as much as we have had examples of aerial mechanics, that is not the norm. Problems need to be managed in the air since you can't just "pull over".

author: BradC
author_rank: Super Contributor
timestamp: June 28, 2017, 04:01:30 am
content: Quote from: SkyMaster on June 28, 2017, 02:08:44 amWhich can actually be determined by its ETOPS-240 rating. So if the aircraft is deemed airworthy by the pilot in command, any airport within 240 minutes flight time might be deemed suitable by the airline/pilot. I'm not defending the actions of the pilot or airline however.

author: BradC
author_rank: Super Contributor
timestamp: June 28, 2017, 04:06:48 am
content: Quote from: SkyMaster on June 28, 2017, 03:03:14 amTrue. The B767 was mis-fueled by a Canadian crew, and it appears the A330 was mis-maintained by a Canadian crew. So while the flight crew who saved the day in both instances were Canadian, the direct cause for both failures was also Canadian. Whilst both landings were a miracle of properly trained Canadians, they could have both been prevented by properly trained Canadians. That's a draw I reckon

author: boffin
author_rank: Unknown
timestamp: June 28, 2017, 06:34:03 am
content: Quote from: SkyMaster on June 28, 2017, 02:57:30 amActually there are a heck of a lot more than that in terms of singles flying commercially, and carrying passenger. There are plenty of aircraft around here like the DHC-3 Otter and DHC-2 Beavers, along with Cessna 206/207, and even 172s and 182s in commercial service. I can even think of a PA28 Piper Warrior II flying for a (small) airline commercially.And lastly, it's not Pratt and Whitney that makes the PT-6, it's Pratt & Whitney CANADA.

author: Gyro
author_rank: Super Contributor
timestamp: June 28, 2017, 09:22:08 am
content: There was another serious metal ingestion type engine 'technical issue' that seriously disrupted a flight on Tuesday, also an Asian flighthttp://www.bbc.co.uk/news/world-asia-40421811

author: VK3DRB
author_rank: Super Contributor
timestamp: June 28, 2017, 10:54:48 am
content: I wondered how you'd feel if you were in the aeroplane's toilet and the plane shuddered like that. Or the air hostess just served you meal or drinks. Would they spill or fall off?

author: BradC
author_rank: Super Contributor
timestamp: June 28, 2017, 11:00:41 am
content: Quote from: VK3DRB on June 28, 2017, 10:54:48 amIf you were in the toilet that would expedite your movement, or probably create an unplanned one, and yes you and the people adjacent would all be wearing your food. Not my idea of a good time.

author: IanMacdonald
author_rank: Frequent Contributor
timestamp: June 28, 2017, 12:06:10 pm
content: Quote from: SkyMaster on June 28, 2017, 12:04:17 am'Why did you divert here when the other runway was closer?''Because I wanted the passengers to remain in their seats for safety's sake.. and this destination was conveniently on the same heading as Mecca.'

author: SkyMaster
author_rank: Frequent Contributor
timestamp: June 28, 2017, 09:42:05 pm
content: Quote from: BradC on June 28, 2017, 04:01:30 amETOPS-240 is not a permission to allow an aircraft to fly for 240 minutes on one engine. ETOPS-240is a restrictionthat is forcing the aircraft to fly along a route that keep the aircraft within 240 minutes of a suitable airport for landing in case of an emergency.

author: SkyMaster
author_rank: Frequent Contributor
timestamp: June 28, 2017, 09:54:39 pm
content: Quote from: boffin on June 28, 2017, 06:34:03 amboffin, you are correct, there is a lot of single engine commercial operations in Canada; Aerial work and Part 703. But they are all restricted to VFR (Visual Flight Rules); none of them can operate IFR (Instrument Flight Rules) with passengers.The Pilatus PC-12 and Cessna Caravan are the only single aircraft that can operate IFR while carrying passengers in Canada. I don't know how an airline could operate profitably if it is restricted to VFR.And thank you for pointing out that all PT-6 are build in Canada; all the good stuff is made in Canada

author: StillTrying
author_rank: Super Contributor
timestamp: June 28, 2017, 11:02:12 pm
content: Quote from: IanB on June 28, 2017, 02:34:19 amA crash ?

author: Cerebus
author_rank: Super Contributor
timestamp: June 29, 2017, 12:14:41 am
content: Quote from: SkyMaster on June 28, 2017, 09:54:39 pmMaybe, possibly, but we do know thatallthebeststuff's made in Japan.

author: ConKbot
author_rank: Super Contributor
timestamp: June 29, 2017, 04:16:33 am
content: Quote from: IanB on June 28, 2017, 02:34:19 am"On final approach"https://en.m.wikipedia.org/wiki/ETOPShad some info on regulations on twin engine aircraft operating on one engine. It looks like aircraft that aren't ETOPS certified must remain within 60 minutes of a diversion site, and aircraft can be certified for up to 3 or more hours of range from a diversion site. Still an emergency though.Kind of interesting that a fully functional engine, as heavily maintained as they are (or not, but that's a different story) is only reliable enough that the risk of a second failure is only statistically small for 1-4 hours.

author: Nusa
author_rank: Super Contributor
timestamp: June 29, 2017, 05:31:17 am
content: Quote from: ConKbot on June 29, 2017, 04:16:33 amThat would depend on why the first engine failed, which is often not known until after landing. Things like bad fuel or faulty maintenance procedures could mean a 2nd engine failure is coming.

author: Brumby
author_rank: Unknown
timestamp: June 29, 2017, 07:08:28 am
content: Quote from: StillTrying on June 28, 2017, 11:02:12 pmIf an aircraft has some altitude to work with, the pilot will be able to dosomething. Whether they can make a successful landing or crash, depends on the terrain within their range. As said earlier - an unpowered aeroplane becomes a glider.There is a similar capability in a helicopter, called autorotation - but from my limited understanding ... it's much more challenging than a fixed wing glide.

author: james_s
author_rank: Super Contributor
timestamp: June 29, 2017, 07:36:10 am
content: Quote from: Nusa on June 29, 2017, 05:31:17 amOr bird strikes, which as we saw a few years ago can take out both engines. If there is something around to be ingested by one engine, there's a reasonable chance it will be ingested by one or more of the other engines.

author: BradC
author_rank: Super Contributor
timestamp: June 29, 2017, 08:39:21 am
content: Quote from: SkyMaster on June 28, 2017, 09:42:05 pmYou are, of course, absolutely correct. I really didn't communicate myself properly when posting that. What I meant was that it is entirely possible that Air Asia don't even have Learmonth listed in their flight manuals as a suitable diversion, and as such Perth was the closest "suitable" diversion still within the ETOPS-240 allowance that the flight crew were "aware" of. Qantas use it, but different airline with different operating procedures.Again, it'll all come out in the investigation.

author: Yansi
author_rank: Super Contributor
timestamp: June 29, 2017, 02:47:33 pm
content: Quote from: Brumby on June 29, 2017, 07:08:28 amThats when the gyrocopters come into place!

author: boffin
author_rank: Unknown
timestamp: June 29, 2017, 10:36:02 pm
content: Quote from: james_s on June 29, 2017, 07:36:10 amWe've actually had four-engine ingestion (747s) a couple of times with aircraft flying into ash clouds (once over Indonesia and once over Alaska jump to mind).

author: langwadt
author_rank: Super Contributor
timestamp: June 29, 2017, 10:48:35 pm
content: Quote from: German_EE on June 26, 2017, 08:27:14 amfor the first jet powered land speed record Breedlove had some how gotten hold of a scrapped jet engine from an F-86with a few missing turbine blades, it was balanced by removing opposite blades and ran like that

author: langwadt
author_rank: Super Contributor
timestamp: June 29, 2017, 10:54:56 pm
content: Quote from: Brumby on June 28, 2017, 03:12:26 am

author: CatalinaWOW
author_rank: Super Contributor
timestamp: June 29, 2017, 11:17:35 pm
content: Not being an Aussie, and not wanting to spend time Googling this I don't know what the ground situation is at Learmouth this time of year. Passenger injury or even death is possible at some remote airports from cold, heat exhaustion, critters, transportation injuries, delays in receiving urgent medication and gosh knows what. So it may not have been as cut and dried a decision as it seems to some. The pilots got to sit there in real time and make a decision. In retrospect their decision turned out OK.All of us internet warriors and the transportation safety boards get to make a leisurely decision with little or no personal consequences from the outcome. Hurrah for us!

author: noidea
author_rank: Unknown
timestamp: June 30, 2017, 06:22:40 am
content: Quote from: CatalinaWOW on June 29, 2017, 11:17:35 pmGoogling's not that hardhttps://www.google.com.au/maps/place/22%C2%B014'24.2%22S+114%C2%B005'36.4%22E/@-22.2400081,114.0938326,339m/data=!3m1!1e3!4m5!3m4!1s0x0:0x0!8m2!3d-22.24005!4d114.093437Shelters not an issue there's an air conditioned terminal building as per my previous post and the weather is pretty mild this time of the year ~25C, it actually rained every day I was there two weeks ago.There's some pretty robust discussion going on still in the pprune thread posted earlier about what constitutes a "suitable airport". If they were looking for somewhere suitable to put it on the ground in a hurry it fits the bill, its long enough that C-141's used to fly in and out every week when the US/Aus naval communications base was in full swing and other airlines have used it an emergency below, ie QF72https://en.wikipedia.org/wiki/Qantas_Flight_72My guess the lack of firefighting equipment may have had something to do with their decision but if the plane was potentially going to go up in flames I'd rather it be off the ground with the passengers sitting on the runway than flying nearly 2 hours back to Perth...

author: Howardlong
author_rank: Super Contributor
timestamp: June 30, 2017, 10:20:36 am
content: Quote from: StillTrying on June 28, 2017, 11:02:12 pmNot really, I've landed countless times in a SEP* with no engine. Operations without an engine are a key, and significant, part of SEP pilot training. This also includes methods of picking convenient places to land that doesn't include built up areas.*SEP: Single Engine Piston fixed wing aircraft

author: coppice
author_rank: Super Contributor
timestamp: June 30, 2017, 12:43:12 pm
content: Quote from: Howardlong on June 30, 2017, 10:20:36 amI find it strange that almost everyone knows that gliders exist, yet many assume a powered plane will plummet as soon as its out of power. The only type of aircraft in danger of that today are advanced military aircraft, which require a mass of clever gizmos functioning normally to have any stability. It may happen that future civilian aircraft move in the direction of no inherent stability, but none are like that today.

author: james_s
author_rank: Super Contributor
timestamp: June 30, 2017, 03:34:34 pm
content: They won't plummet, but they won't glide nearly as well as a plane that is designed as a glider, and if you're not expecting to be without power you may not have much time to find a suitable place to land. A true glider can remain in the air for a rather long time utilizing thermals to gain altitude, a powered aircraft with a dead engine is going to go down fairly quickly.

author: coppice
author_rank: Super Contributor
timestamp: June 30, 2017, 03:52:51 pm
content: Quote from: james_s on June 30, 2017, 03:34:34 pmIf you turn off the engines of an airliner at cruising altitude it takes around half an hour for the plane to glide to the ground. I think that's some pretty good gliding.

author: Cerebus
author_rank: Super Contributor
timestamp: June 30, 2017, 03:55:51 pm
content: Quote from: james_s on June 30, 2017, 03:34:34 pmAn A330 has a quite respectable glide ratio of around* 15:1. For comparison a Cessna 172 (single engined small plane) is around 9:1 and a pukka 'glider' can be around 40:1.Given the typical flight levels of commercial jets (say 30,000 feet) and a worst case glide ratio of, say, 10:1, a commercial jet could cut all its engines and still have 57 statute miles (92 km, 49 nm) of forward flight before it reached the ground.* I say "around" because the glide ratio of any plane is going to depend a lot on circumstances.

author: mrpackethead
author_rank: Super Contributor
timestamp: June 30, 2017, 05:01:26 pm
content: Its quite possible that the aircraft did not have a fuel dump system, and that the fuel load would have put the aircraft over the Max landing weight, and the fuel had to be burned off.. so they had to fly somewhere.I'd wait to i had all the facts, on this before i made any judgment calls.

author: james_s
author_rank: Super Contributor
timestamp: June 30, 2017, 06:25:00 pm
content: 15:1 best case is still not something I'd want to deal with on purpose. Even under the best circumstances you really only have one shot to line up and land, you can't go around. Then there is the matter of managing your speed, there's a rather narrow window between too fast and too slow, and on top of that you can't put a jetliner down in one piece on a residential street like you can with a Cessna. There have been a few incidents of gliding an airliner in to a successful landing and in those an enormous amount of luck and skilled piloting were involved. There have been many more cases where loss of power resulted in a fatal crash.

author: SkyMaster
author_rank: Frequent Contributor
timestamp: June 30, 2017, 07:18:23 pm
content: Quote from: mrpackethead on June 30, 2017, 05:01:26 pmSwissair flight 111 took the time to dump fuel instead of racing to the diversion airport; it did not work for them.

author: mrpackethead
author_rank: Super Contributor
timestamp: June 30, 2017, 07:31:22 pm
content: Quote from: james_s on June 30, 2017, 06:25:00 pmSingle engine landing and go around on A330 is part of ETOPS, You woud'nt want to be doing it overweight, though.

author: Nusa
author_rank: Super Contributor
timestamp: June 30, 2017, 08:06:38 pm
content: Quote from: mrpackethead on June 30, 2017, 05:01:26 pmThat's a operational rule to minimize stress on the airplane, not an inability to land. In an emergency the captain can make the call to land overweight anyway. Doing so will require the plane to be grounded for an expensive inspection before they'll let it fly again, but in an serious emergency that's not important.

author: james_s
author_rank: Super Contributor
timestamp: June 30, 2017, 11:07:26 pm
content: I'm not talking about single engine landing, I'm talking about complete loss of power landing. It has been done, but it's anything but routine and not something I would ever be eager to try. The plane won't simply fall out of the sky but it's not going to be a leisurely event either.

author: Nusa
author_rank: Super Contributor
timestamp: June 30, 2017, 11:34:11 pm
content: Quote from: james_s on June 30, 2017, 11:07:26 pmIf they are in range of a suitable airport and there's nothing compromised about the flight controls or surfaces, it's going to be ok. These pilots have many thousands of flight hours and serious training for emergency scenarios on every aircraft they're certified to fly. All-engines-out is right at the top of the list of serious emergencies. No it's not routine, but they're far more prepared for anything than the average pleasure pilot.It's when there isn't a suitable landing spot or when flight controls are crippled that things get really scary.

author: james_s
author_rank: Super Contributor
timestamp: July 01, 2017, 12:18:18 am
content: That's a big if. There have been numerous complete loss of power incidents where the flight controls were operational that still ended in fatal crashes and only a few come to mind as having been successful and those all involved a tremendous amount of luck and skill. One was the 767 at Gimli, one was the Airbus that ditched in the Hudson, and I think there was at least one other. If an airliner suffers a complete loss of engine power that is a dire situation that is not going to end well without a lot of luck.

author: SkyMaster
author_rank: Frequent Contributor
timestamp: July 01, 2017, 01:20:43 am
content: Quote from: Nusa on June 30, 2017, 11:34:11 pmThe average pleasure pilot has a clear advantage. The average please pilot is flying a single engine piston aircraft, with stiff legs, in day VFR. The best gliding speed of his airplane is relatively slow, as is the touch down speed. A strait stretch of road, an open field or even a large empty parking lot will be enough to execute an emergency landing.An all engine-out situation in a jet aircraft, at night and/or IFR is a receipt for a disaster. The ones that made it ok were in day VFR condition. I do not recall any jet aircraft that was able to make a successful landing after a dual engine flame out at night and/or IFR.Are there any example?

author: SkyMaster
author_rank: Frequent Contributor
timestamp: July 01, 2017, 01:25:37 am
content: Quote from: james_s on July 01, 2017, 12:18:18 amThe other one that you are thinking about is probably the Air Transat A330 that ran out of fuel over the Atlantic in 2001. It was at night but the sky was clear, but by the time they reached the airport where they made a successful (but somewhat hard) landing they were in daylight.

author: IanB
author_rank: Super Contributor
timestamp: July 01, 2017, 01:48:36 am
content: Quote from: SkyMaster on July 01, 2017, 01:20:43 amThis also depends a little on the cooperation of the people on the ground. Not so long ago in an incident near me a pilot faced with total engine failure elected to land on a freeway, it being the most available flat, level surface. Most of the drivers saw what the plane was trying to do and got out of the way. One driver panicked and braked to a halt in the path of the aircraft. The resulting crash between aircraft and car was not pretty.

author: Nusa
author_rank: Super Contributor
timestamp: July 01, 2017, 02:04:04 am
content: Quote from: james_s on July 01, 2017, 12:18:18 amBoth situations that were NOT within range of a suitable airport.Captain Sully lost both engines at low altitude right after takeoff and couldn't make any of the airports in the area...the Hudson was the best option left to him.The Gimli glider landed at an ex-airbase that had been converted to a racetrack. The luck was in not killing anyone on the ground. There was a large rally in progress, and some kids got the scare of their life.

author: Nusa
author_rank: Super Contributor
timestamp: July 01, 2017, 02:19:37 am
content: Quote from: SkyMaster on July 01, 2017, 01:20:43 amIf they are in range of a suitable airport(bolded this time, but I said it above too) I contend that an IFR approach and landing is within the skill-set of an airliner pilot. Even with engines-out, there's nothing wrong with the nav equipment or the runway lights. I don't need an example of it happening to believe that.I agree with you when they AREN'T in range of a suitable airport. What's your point?

author: SkyMaster
author_rank: Frequent Contributor
timestamp: July 01, 2017, 02:58:12 am
content: Quote from: Nusa on July 01, 2017, 02:19:37 amMy point is simply that there is no such thing as an all engine-out (gliding) IFR approach profile. I am not aware of any situation were an all engine-out jet aircraft was successfully landed on a runway at night, let alone in IFR condition, even day IFR. I know of a few cases were the pilots were desperately trying to locate the runway, until they ran out of altitude.

author: Howardlong
author_rank: Super Contributor
timestamp: July 01, 2017, 05:08:32 am
content: Quote from: SkyMaster on July 01, 2017, 01:20:43 amThere's an interesting difference in training between countries, in the UK options such as roads, parks and golf courses are all off limits for consideration as suitable precautionary or emergency landing options. I can't think of a car park large enough in the UK to land. Pretty much you need to find a field in Blighty, or ditch on water.

author: coppice
author_rank: Super Contributor
timestamp: July 01, 2017, 05:38:20 pm
content: Quote from: SkyMaster on July 01, 2017, 02:58:12 amWhy would the lack of engine power affect the use of IFR for landing?

author: Cerebus
author_rank: Super Contributor
timestamp: July 01, 2017, 06:54:21 pm
content: Quote from: coppice on July 01, 2017, 05:38:20 pmI think you're confusing the intent. SkyMaster was talking about IFRconditions, commercial flights are always operated under Instrument FlightRuleseven under VFRconditions.

author: SeanB
author_rank: Super Contributor
timestamp: July 01, 2017, 07:25:59 pm
content: IFR relies on having power for the systems like hydraulic pumps, computers and air data computers. With all engines out you are only going to have the battery bus, the standby emergency inverters and if there a RAT to provide operational power, all other systems will be sacrificed for to give the pilots a small amount of hydraulic power for control surfaces ( and then not all of them, but only flight critical systems like rudder, elevators and elevons, and possibly a limited ability to engage high lift devices) and will rely on gravity and a hand pumped system to lower the landing gear to the point where it falls and locks with gravity and airstream assist.Remember aircraft systems like autopilot require quite a lot of power in normal operation, a good few kW of power drawn off the engines to provide hydraulic systems, electrical power and importantly cooling of these computers. Lose all engine power ( we assume the APU is dead as well, because if it is not then the APU can at least supply the critical AC buses and the critical hydraulic systems, no aircon in the cabin, no pressurisation and no in flight entertainment systems or toilets) and you are sitting with the 2 in front having to do all the work, no automation to help them, a single radio system available for calling to ATC to declare the emergency, the flight data recorders powered up for the inquest, and the only instruments they are guaranteed to have are the turn slip indicator, the magnetic compass, an airspeed indicator and a standby artificial horizon. Modern glass cockpits still have those as real physical instruments, along with the clock, and in emergency there will be a single CRT or LCD display at most available per pilot for any other displays, and only basic air data from one system running in a very degraded mode.Basically at this point the pilots are either going to make it, or not. You need at least one good engine and an APU on most modern commercial aircraft ( MD80 and other tri engine units excepted, where you need at least one on the wing running at full power and the back end not having grenaded the hydraulic systems) to at least have controls, and on a 4 engine aircraft at least one per wing running, otherwise you will torque over into a roll.There were quite a few early 747's that took off to cross the Atlantic with 4 engines, and which landed 8 hours later on the other side with 3, the fourth having suffered an in flight failure and fallen off into the ocean, and the shortest path to a suitably rated airport was the destination, where they had a direct path and no parking burning a hole in the sky either. Return was longer, and diversion to Grand Canaris was not suitable as they would have exceeded the runway length with degraded thrust reversal ability.

author: mrpackethead
author_rank: Super Contributor
timestamp: July 01, 2017, 07:33:24 pm
content: Im amazed at the number of pilots with large jet experience we have in this electronics forum. Such a talented bunch we are.

author: coppice
author_rank: Super Contributor
timestamp: July 01, 2017, 07:38:59 pm
content: Quote from: SeanB on July 01, 2017, 07:25:59 pmWhy would the loss of the fans affect the APU? That would normally be startable after all the fans have died, and all flight systems (other than the fans, of course) should be able to carry on as normal.

author: SeanB
author_rank: Super Contributor
timestamp: July 01, 2017, 08:37:10 pm
content: Quote from: coppice on July 01, 2017, 07:38:59 pmRemember I said all power is lost, including APU. If APU is available then you have power and also an important ability to get into the flight regime for an in air relight of at least one engine. Battery power alone will give you at best a single engine restart ability if the APU does not relight, and in most aircraft these days the APU will be powered off after climb, to conserve fuel, automatically, so it might survive whatever took all the engines out and be capable of at least 2 attempts to start ( lower load on the battery bus to do so) and provide power. You need a running APU for the best chance of an in air relight of one engine, and then that single engine ( some limitations depending on aircraft type and engine configurations as well here can also play in this) and the APU can do a relight of others, providing the cause of the engine failures was not a fuel or mechanical issue, and the engines are capable of operating again to provide thrust.However the typical cause of engine failures in flight are not a thing that you can restart from. They typically are either physical failure of the turbine, failure of the hydraulic system, failure of a rotating component or bearing ( wear detector will shut down the engine if it detects sudden abnormally high particulate contamination in the hot engine return hydraulic fluid), fire system detectors detecting continuous overtemperature in the engine nacelle, or fuel system pressure abnormality that exceeds limits, or a fuel pump or filter failure. High EGT will result in a failure warning, and in most cases a massive reduction in engine power allowed, till either the engine is shut down, or another system shows the cause for the high EGT, typically a seal failure allowing oil into the combustion chamber or some fuel system failure, or the thermocouples burning out.Basically you can have a single engine failure and still fly, but if more than one goes out you are looking for the crash site, and if there will be survivors.

author: james_s
author_rank: Super Contributor
timestamp: July 02, 2017, 05:50:46 am
content: Quote from: mrpackethead on July 01, 2017, 07:33:24 pmHow many? I'm not seeing a lot of people claiming to have large jet experience. A couple of people who seem to be reasonably knowledgeable about aviation, they may be pilots or it may just be a topic of interest. I'm in the latter category, aviation is something that has always been of great interest to me but not something I chose as a career path because it wouldn't fit my lifestyle to be away from home so much. I can't afford to fly full scale as a hobby so I stick to flying model aircraft. One doesn't have to be an experienced airline pilot to be knowledgeable or weigh in on the matter. That said, I've refrained from stating an opinion on the judgement of the flight crew in this incident. I wasn't in the cockpit or onboard the plane so I'm going to assume that the pilots made a reasonable decision based on all of the information they had at hand.

author: mrpackethead
author_rank: Super Contributor
timestamp: July 02, 2017, 01:21:56 pm
content: Quote from: james_s on July 02, 2017, 05:50:46 amWise. I am a 'pilot'. ( little single piston engines ). Have personally known several folks who are no longer with us, because of 'incidents' that occured. What was very upseting at the time, was the rumor and speculation of what happened.

author: SkyMaster
author_rank: Frequent Contributor
timestamp: July 02, 2017, 01:55:06 pm
content: Quote from: coppice on July 01, 2017, 05:38:20 pmAn IFR approach requires the aircraft to fly along a very precise route over fixes on the ground, at specified altitudes. This is done in order to position the aircraft for the final approach phase, where the aircraft is aligned with the runway, at the correct altitude. The goal being to maintain sufficient separation between the aircraft and the ground or any obstacle. When on final approach (aligned with the runway), the aircraft is descending on a slope of 3° (typically). 3° is fairly flat and engine power is required to maintain this slope of 3°. Engine power is required at all phases of a flight done under an IFR flight regime.Even the visual approach slope lights installed on the side of the runway threshold are adjusted for the 3° slope. A gliding aircraft, in landing configuration, is descending at an angle much more steeper than 3°.In an emergency scenario where all engine power is lost, to make it to a runway, the meteorological condition would need to be such that the crew can see the runway as early as possible in order to make an approach in visual condition. Sky clear and unlimited visibility, in daylight, would be ideal for this scenario.

author: SeanB
author_rank: Super Contributor
timestamp: July 02, 2017, 02:13:05 pm
content: Quote from: mrpackethead on July 02, 2017, 01:21:56 pmThat is one reason i really will never fly in a plane where I am going to be an appreciable part of the allowable mass. He was killed out at sea for some reason, hard to determine what caused the accident, just he went into the ocean and was killed along with the passenger.