As I write this, AirAsia flight 8501 has been missing for less than 24 hours, and in the absence of wreckage its too early to speculate on what happened. But the flight, which took off from Surabaya bound for Singapore, appears to have been traveling through an area of intense thunderstorm activity, so it may be instructive to look at the kind of danger this sort of weather can present to aircraft.
The region around the equator is known to meteorologists as the Intertropical Convergence Zone, or ITC. Here, the heat and moisture of warm ocean waters provides the energy to power tremendous updrafts that produce clusters of thunderstorms called a Mesoscale Convenction Complex. These storms can punch up through the stratosphere up to 50,000 feet, far above the crusing altitude of commercial airliners. From Smartcockpit.com:
A thunderstorm brings together in one place just about every known weather hazard to aviation. A single thunderstorm cell can hold 500 000 tons of water in the form of liquid droplets and ice
crystals. The total amount of heat energy released when that much water is condensed amounts to approximately 3 x 1014 calories. Equated with known energy sources, this falls just below an entrylevel hydrogen bomb. Even a small thunderstorm would have the caloric equivalent of a Hiroshimatypeatomic weapon… The thunderstorm occupies a unique place in the pantheon of aviation meteorology because it is the one weather event that should always be avoided. Why always? Because thunderstorms are killers.
Some of the deadly forces include lighning, airframe icing, large hailstones, extreme turbulence, and downdrafts that can reach speeds in excess of 100 mph. Perhaps the greatest hazard facing a modern airliner, however, is the sheer volume of precipitation that a thunderstorm can put out.
On May 24, 1988, a TACA 737 en route from Belize to New Orleans was descending towards its destination when it blundered through a thunderstorm. At an altitude of just 2000 feet, a deluge of rain and hail doused the flames of its twin turbofans. Unable to regain power, the captain managed through superb airmanship to put the stricken plane down undamaged atop a mile-long levee. Notes superb aviation writer Peter Garrison:
The event was not unique. Nine months earlier, an Air Europe 737 descending through rain and hail over Thessaloniki, Greece, had suffered a double flameout. In that case, the crew managed to restart the engines and land without trouble. In 2002, a Garuda Indonesia 737, also descending among thunderstorms, suffered a double flameout over Java. Its crew ditched the airplane in a river; one person died, and there were a dozen serious injuries.
According to preliminary reports, the pilot of QZ8501 had asked air traffic control for permission to ascend from 32,000 to 38,000 feet in order to evade the weather. Historically, however, attempting to fly over a thunderstorm has proven a dangerous strategy. In 2009, Air France 447 was flying through the upper reaches of a thunderstorm when it hit turbulence and its pitot tubes froze, leading to loss of airspeed indication; in the ensuing confusion the pilot flying lost situational awareness and flew the plane into the ocean.
It is worth noting that in the vicinity of strong thunderstorms, the vertical airspeed can change very abruptly from very strong up to very strong down in <1NM horizontal. Thus, very strong vertical wind shear is common. The fact that UAE409 was close by (~30NM west) and apparently not experiencing these conditions is not surprising. The biggest vertical speed change problems are very localized. Flying into such conditions at high speed causes very high instantaneous G loads.
PK-AXC seems to be only about 6 years old, but does multiple takeoffs and landings each day in the region. Perhaps an Aloha Airlines 243 type of scenario?
Layman here. Fascinating discussions on this site! Pardon my ignorance, but I am curious.
If this is weather-induced:
1. Would the transponders not have gone off by now? (if crashed/in water)
2. Wouldn’t the pilot/crew be able to send a distress signal in the seconds following?
And if not, any way to equip a commercial jet to auto-trigger a distress signal if it drops, say a X-feet withing a certain timeframe?
I guess if it’s weather we’ll have our answer shortly.
But given what we know of MH370, immediately after this disappearance maybe they should’ve scrambled some jets to FIR boundaries/alt flight paths just in case.
Just seems so odd..
The Aloha plane was 19 years old, built in 1969. It had almost 90,000 cycles and was doing 20 minute flights. It would be impossible for an A320 built in 2008 to have achieved that level of use. Even if it had been used as heavily as 243 had been, unlikely since airlines have taken steps to avoid concentration of cycles on one plane, it would only be up to 30,000 cycles. 30,000 should be a non-issue for a short haul airliner.
PK-AXC made roughly 6 flights a day:
“The aircraft had accumulated about 23,000 flight hours in some 13,600 flights, according to Airbus.”
Reuters — http://tinyurl.com/pawjt2h
“Geoffrey Thomas, of airlineratings.com, told the BBC that radar plots had shown the plane was flying at 353 knots, 100 knots slower than it should have been.
Although he stressed it was only speculation, he said it was possible the pilots may have lost data on air speed because of an ice-up of pitot tube instrumentation. This was thought to have had happened in the loss of the Air France Airbus A330 over the Atlantic Ocean in 2009.”
BBC — http://tinyurl.com/p44c49c
The stall margin at altitude is very small, [which is one of the reasons that airlandseaman found a deal of difficulty in hand flying the B777 Sim manually at altitude]. Severe turbulence in CBs , at a high altitude, and possibly climbing too, is a recipe for disaster, especially if the crew are already stressed, having been denied a clearance to climb. If the aircraft enters an aerodynamic stall it could take 20,000 ft to recover, in the best of conditions. Potentially similar conditions to AF447.
Better to fly over a thunderstorm than through it. The AF 447 pilots wanted to fly over it, but didn’t because they thought the outside air temperature was too high. Instead they tried to avoid the it by making a 12 degree left turn.
It would be great if INMARSAT (or whichever satellite company is involved) could release the satellite data early to the public to avoid a repeat of MH370.
@Denver: It has been reported that QZ8501 had not satellite capability and probably no ACARS subscription.
YOUTUBE: AirAsia FLIGHT #QZ8501 Full FlightRadar24 HD ‐1.5042S, 107.362E
“Earlier Reports Suggest The FlightRadar24.com site end point of radar was 3.2466S 109.3682E and Before that 3°36’31.0″S 109°41’46.0″E and even a wild report of 3.09 15S , 111.28 21E.
Attached is a Video Playback of the ACTUAL Full Radar Field for FlightRadar24.com and a picture is also provided showing the True LAST Known Location of ‐1.5042S 107.362E for all to see themselves.”
https://www.youtube.com/watch?v=bS7J2xEKypo&feature=youtu.be
@Nihonmama: In the video, the black dotted line represents the extrapoloated (i.e., estimated) position based on a constant track and ground speed. Notice the radar station changes from F-WARR2 to T-EST1.
Great job on CNN, Jeff.
I would be much obliged if, before you leave their studios, you’d be so kind as to pass on my request: that they re-interview the anonymous “US officials” that “confirmed” the co-pilot cell phone ping that we now understand to be incompatible with the primary radar track.
I believe the original CNN article appeared Apr.14. Thanks in advance.
And again the 7th arc if I am not mistaken… I mean QZ8501.
Condolences to families and friends of those, who were onboard.
Victor:
“Notice the radar station changes from F-WARR2 to T-EST1.”
Not quite sure of the takeaway, but are you meaning something similar to @gerry_vienna? (posted in previous thread):
“FR24 ADS-B receivers there. Radar ID “T-EST2″ also indicates that (EST=estimated). CNN needs to be told.”
I’ll keep an ear on the news today but I’m having the occasional – surely not – moment waiting for wreckage to show up. No distress call, no beacon, and anyone who ever flew has been diverted because of weather. Of concern would be that it should have been an open and shutter, and bits of junk are being spotted/disregarded up to 1100 km away.
@nihonmama: The takeaway is that the accompanying text is wrong regarding the last known FR24 ADS-B position for QZ8501. Only the first part of the track is valid for the reason I cited. That is also what @gerry_vienna is trying to say. The poster (and I can guess who it is) is misinformed.
@ Bruce Lamon
In regard to going over the storm, I believe the weather guy on CNN yesterday said this storm topped out at 52,000-53,000 feet.
@ Matty – Perth
In January 2007 it took over a week in Indonesia to find pieces of Adam Air 574 which was also lost in a thunderstorm while flying at about 35,000 feet.
Today the search will move to include land. This can’t be going well.
Thanks Victor.
@Matty – actually, there ARE some reports coming from Australia about debris, according to Jusuf Kalla.
I am still completely awestruck by Richard Quest’s comments to the effect that this isn’t the deep Indian Ocean in this case. Hindsight is usually 20/20, but in this case the rear view mirror appears to be fogged up. MH370 wasn’t in the “deep Indian Ocean” at this stage either. In fact, we could argue that it still isn’t, for practical purposes, because we haven’t found it yet.
I’m inclined to think that QZ8501 is indeed at the bottom of the Java Sea but I am very disturbed by the sheer nonsense coming out or being presented to the media.
Until further developments, this event is EXACTLY like MH370.
@Bruce L: In regard to flying over the storm, the weather guy on CNN yesterday said this storm topped out at 52,000-53,000 feet.
@Matty: It took over a week to find parts of Adam Air 574. It was lost while flying at about 35,000 feet in a thunderstorm over Indonesia in January 2007.
@JS: At some time in the very near future, if no evidence of a crash is found in the current search area, it is time to start demanding the release of the raw primary radar data, the ADS-B data, and the unredacted ATC communications. We as a group of private citizens are much more knowledgeable, much better organized, and much less gullible than we were at this point in the MH370 incident.
Victor – I could not agree more. I have a feeling, though, that if the situation doesn’t progress beyond unrelated oil slicks, debris, and pings (the audible variety), I think there will be nothing short of an uproar.
Right off the bat I’d say that these locator beacons appear to be useless. I’m disinclined to load up a plane with more equipment for rare events, but at least the equipment it possesses should do what it was designed for.
The cynical side of me, unfortunately, says that this time, we will not hear of any ping rings, radar sightings, radar non-sightings, cell phone connections, or any of the other “facts” that led to the impression that any government agency was incompetent. I suspect this time will consist of Tony Fernandes playing a competent, compassionate airline boss, with a gag on everyone else.
No need for another peanut gallery, right?
@JS: I agree about the uproar if solid evidence is not found. That is why I keep harping on the primary radar data. It is easy to understand (no complicated communication satellite physics) and would tell us a lot more than the FR24 data we have now. And this time, we will not be fooled into believing that the military and the transportation ministries don’t share data in a timely manner.
AirAsia flight QZ8501: final communications from pilot of missing plane revealed
December 30, 2014 6:36 am
Michael Bachelard
http://t.co/nrKOczINjn
“A senior Indonesian aviation source tells Reuters that authorities have the flight’s radar data and are waiting for search and rescue teams to find the debris before starting their investigation.”
It seems to me that once again, we have a conundrum. If the plane went down in one piece, shouldn’t there be either an ADS-B- or a transponder-reported altitude below the 32,000 feet? There should have been time.
Also, since when do planes depart two hours early? Is that a regional thing?
From same SMH article:
“Relatives wanted to know why the departure time of QZ8501 had been brought forward from 7.20am to 5.20am on Sunday. They were told it was just a routine change.”
How do you move a flight departure UP TWO HOURS? Particularly so if you’re turning the in-bound. I’ve NEVER seen that happen anywhere, ever. Neither as a traveler nor as a (former) gate agent.
Switching topics, let’s return to the “Signal Unit Logs”, for which the ATSB provided an update on Dec 23. The update consisted of adding two lines to the start of the log – the “Log-On Request” messages at 15:59:55 and at 15:59:56, just seconds before the previous 16:00 cut-on. What do we learn from these messages? In conjunction with the messages immediately following, we learn that the sequence of messages at this logon is different from those at the 18:25 and 24:19 events later on. Normally (according to the “MANUAL FOR AERONAUTICAL MOBILE SATELLITE (ROUTE) SERVICE”), a Log-on Request is initiated by the AES and send over an “Rsmc” channel, at which point the GES responds with a “Log-on Confirm” using a “Psmc” channel, followed by a subsequent broadcast of a new set of P/R (so-called Pd and Rd) channels and T channel assignments to be used for future communications. We see the P/R and T messages at 18:25 and 24:19, but not at 16:00. In fact, just after sending the “Log-on Request” message at 15:59, the AES immediately switches from the Rsmc channel (36F8) to the Rd channel (36D3) without being told to do so. My guess is that the 15:59 event is a “Log-on Renewal” request, but the sequence of events for a renewal is not found in any documentation that I have at hand. Anyone?
JS – Looks like they were trying to adhere to a schedule for the QZ8501:
http://www.flightradar24.com/flight/qz8501
I guess it’s a discussion for post-rescue but seems like potentially a profit-before-safety thing happened, for one.
They push a flight ‘earlier’ (closer to storm), in crowded airspace that squeezes flights so tight that pilots can’t navigate if needed. Hmm…
Why did it depart 2 hours early is an excellent question.
I would think that Leo has probably nailed, with the caveat that the flight was perhaps advanced to hours in the interest of avoiding extreme weather.
If weather happens to emerge as the larger contributing factor, then perhaps someone has threaded the needle a little too closely; I suppose heads will roll in this instance, as advancing the flight (awareness of the extreme weather) would provide foundation for claims of negligence. Nihonmama has already highlighted how anomalous is the change; if it is ignored in any investigation, then perhaps we will know that it is claims of negligence that the authorities are attempting to avoid. In line with what Victor said, we should raise holy hell if, as with the radar data, there is not complete transparency in this regard. My guess is that there won’t be, and that we will be quite busy.
Here are where the similarities to MH370 are to be found: the hierarchy has structured things in such a way as to produce opportunities for malfeasance on the part of the authorities. It’s no different than the International Criminal Court: US interests have NEVER served All, and it would appear that the ICAO needs its own independent investigation body and perhaps a set of titanium incisor implants.
I’m confused by this talk of the flight leaving two hours early. According to Flightradar24.com, it left the same time as always:
http://www.flightradar24.com/data/flights/qz8501/#5240449
(Note that its departure date is 12/27, since time is UTC; I don’t know why its status is given as “landed.” Unless I’m totally reading it wrong)
Rand, Leo:
Having flown(and worked) many flights where extreme weather was expected, one of two things is going to happen from an operations perspective: the flight is delayed, cancelled or if you hit that weather mid-flight, you are re-routed around the weather.
A flight may (legally) push off the gate a few minutes early if all checked-in pax are boarded, in order to make take-off slot. But But advancing the departure by TWO HOURS for weather?
Sorry, NOPE.
“@turnermx: @nihonmama @tamarindlemur unheard of to move ahead departure time. I fly a hundred times a year.”
https://twitter.com/turnermx/status/549730459756679169
Ok, so the fattest solution is that its apocryphal, the flight did not depart two hours early. Nihonmama, can you confirm either way?
re the early departure time, I came across this article…
http://www.straitstimes.com/news/asia/south-east-asia/story/airasia-flight-qz8501-unread-email-sees-family-10-miss-flight-201412
@Jeffwise – it is reported (huffingtonpost, as an example) that numerous folks missed the flight because they missed an email saying it was departing early. There were 23 no-shows, which seems excessive for a flight of 170 passengers, IMO.
@nihonmama – I have several hundred flights myself and I have also never heard of this.
That said, I have occasionally seen a scenario which may explain this. I have had flights delayed several hours, only to be un-delayed and leave near the original departure time. Generally this happens when they pull a spare in from somewhere or another flight gets cancelled. I always wondered – what about the people they told to go have a beer for two hours who then come back to learn the plane left?
So perhaps that is what happened here. The news accounts aren’t thorough enough to explain it.
Note that for 12/31, the scheduled time is listed as 5:30am. So the other possibility is that this was a permanent schedule change that wasn’t communicated.
Jeffwise, All:
I just queried the reporter on SMH piece where the two hour early departure was mentioned. Here’s his reply, which I find wanting:
https://twitter.com/nihonmama/status/549762856795652096
CNN was saying too as Jeff says above that the AirAsia pilot requested a higher flight level (4 I think) minutes before they lost contact I think. Assuming then he was trying to go over the thunderstorm. It doesn’t seem similar to MH370 in the fact that we know there was funky weather out there, yet no debris, no wreckage, no elt’s, here we go again?
And look at the fuselage of this airship, bright red. Did anyone see if AirAsia was out the night of March 7 into March 8 possibly crossing Kate Tee’s yacht?
My heart goes out to the families of the missing of Flight 8501.
Since this airbus seemingly did not have Classic Aero and a satcom link and was not communicating with an Inmarsat satellite, isn’t it a little presumptuous to assume it is on the bottom of the ocean if there are many islands in that sea?
@jeffwise – it was flightstats that lists the 5:20 departure for 12/31. Flightradar24 lists it at 22:20UTC for the last week, while flighttracker shows various times after 7am for every day except 12/31, which it lists as 5:30am. No wonder people missed it.
Looking at the history, I notice something VERY interesting. Most of the flights on flightradar24 go out of coverage for parts of the route.
If you guessed that they go out approximately where QZ8501 disappeared, you’d be mostly right.
All the 8501 flights in recent days were at 05:20 Local. There was no time change.
http://www.flightradar24.com/flight/qz8501
jeffwise – yes, I see ‘landed’ in your link, too. Eerie. Dirty data?
Nihonmama – Thank you kindly for the clarification! Makes sense. And I agree, logically/legally moving ahead just wouldn’t happen.
As a layman, I can only speculate from the generic human-greed/incompetence perspective (delay/cancel = bad business, ‘nothing happens on MY watch’, mis-labelled gate time, etc). Given the region of the world, I wouldn’t even be surprised by anything. JS’s scenario of delay un-delayed makes most sense, but hope we get confirmation.
Had such a flight (illegally moved ahead) gone smoothly, would it have been noticed, I wonder. Not suggested that’s what happened, just wondering aloud.
Either way, so much about this is not right.
OK, so we can disregard ‘no delay’ default to JS’s advance departure, yes or no? One more time into the breach of ambiguity?
As for the QZ8501 disappearing just after going off a public domain tracking system, this is interesting, if true. JS, can you elaborate?
I am interested in seeing whether the depth structure of “the plane departed two hours early and people missed the flight” as reported by the Huffpost proves true or false.
A little side test is whether the media had corrupted our perspective re the facts of the departure time and misled us into embracing an erroneous assumption, which in turn leads us down a rabbit hole of rottenness. It’s chicken:egg::media message:facts; let’s see which is leading us.
@JS:
“Looking at the history, I notice something VERY interesting. Most of the flights on flightradar24 go out of coverage for parts of the route.”
You’re right on point and Jason Rabinowitz tweeted re this:
https://twitter.com/AirlineFlyer/status/549053035813806080
“If you guessed that they go out approximately where QZ8501 disappeared, you’d be mostly right.”
And thank you. You’ve just answered the question I posed yesterday: did point at which 8501 disappeared appear to coincide with part of route out of flightradar24’s coverage?
The reporting is indeed ambiguous.
On my reading, a family of 10 had been booked on a 7:20 flight but AirAsia changed the booking to the earlier 5:20 flight, ie two different flights. The family did not read AirAsia’s email notification of the change and hence missed the 5:20 flight.
My interpretation is supported by the ticket of another family who also missed the 5:20 flight. That ticket was purchased 9 months in advance and shows a departure time of 5:20, ie no reschedule. See http://tinyurl.com/qg44ceq .
There does not seem to be agreement among four flight tracking sites as to the route’s past or future departures. The fact that there is disagreement on 12/31 suggests this is either an ongoing screw up, or I’m confused, or sites are showing time zones differently for past and future flights.
It will probably be part of a negligence claim but it doesn’t appear “weird” in that it doesn’t seem to be limited only to the missing flight.
@Rand – at least on flightradar24, several of the prior flights turn to dotted lines at the same point that the missing flight went off radar. Apparently, others have noticed this as well. Fr24 also displays a message saying part of the flight route is outside coverage.
I did not check the other tracking sites because they want paid subscriptions for historical flight data.
This is one of those weird coincidences. If a plane is missing for a few hours, I’d say there’s a good chance it disappeared at a radar boundary or outside of coverage completely because that’s one way for nobody to notice it missing. AF447 and MH370 both did this. On the other hand, by now every hijacker knows this too.
Leo, JS, Rand:
You’re welcome.
“JS’s scenario of delay un-delayed makes most sense”
It does – but here’s the distinction:
If plane A is scheduled to depart @ 5:00pm but departure is delayed (for whatever reason) until 8:00pm, plane A can legally leave before 8:00 pm if the problem that caused the delay is rectified. But plane with a 5:00 pm departure couldn’t (legally) leave @ 4:00 pm if bad weather were the problem.
As to the 23 no-shows, that’s not necessarily excessive. Airlines book (and over-book) flights depending upon a calculation based on historical passenger loads. No-shows happen a lot, which is the reason for overbooking. If 8501 was carrying 170 pax that suggests it was configured for the higher (maximum) density for that aircraft (180), meaning the flight wasn’t full.
@nihonmama – the 170 was a number I guessed at, so I should put up the real ones.
The Guardian reports 155 passengers in 180 seats. The no shows make the total sold between 178 and 181, depending on whether the infants were “in-arms.”
That sounds slightly low but it doesn’t sound like it’s materially low. I would think that if 23 no shows were normal, a low-fare carrier is Asia would have sold closer to 200 seats (or they would have trouble staying a low-fare carrier.)
@ JS and Nihhonmama
I too noticed the radar non-coverage “hole” near the QZ8501’s announced point of disappearance yesterday.
Pls see —
Sitar_AIRCOM_02.jpg
or…
http://bbr.asia/sita.jpg
I was actually investigating the gaps in radar through/up the Bay of Bengal. I have been curious if MH370 might have gone on the Northern Route and have been trying to see how that would work in light of the BTO/BFO data.
I originally guessed that maybe a highjacked MH370 landed in Chittagong (very Sunni; much radicalism), unloaded whatever/whoever, and then took off in a western, north/western direction. Towards the rough, government-less top of the Golden Triangle.
To my surprise, I found an opening (no radar) from the sea near Chittagong and Cox’s Bazar. The corridor runs across Burma and opens up in northern Burma and the Yunan border. This is a lawless (to put it mildly) region where the Asian Triads operate from and where the peoples are Sunni Muslims (Pagtays Burmese and Hui Chinese).
It is also where the 7th arc cuts across. BTO? Yes. BFO? I don’t know.
And many international 777’s fly that exact route (yes, at flightradar24.com, the colored line becomes black) all day, everyday.
Interesting. And then I noticed the hole where QZ8501 disappeared. Interesting again.
I want to say “coincidental”…but nowadays, who knows???
@JS, Nihhonmama,
Re: QZ8501’s point of disappearance, I found the radar coverage “hole” also on this site:
http://bbr.asia/sita.jpg
I found it by accident while studying a potential northern route for MH370. Note that MH370 could have flown up the center of the Bay of Bengal and then cut westerly (below Cox Bazar) into/across Burma and then northwesterly to the top of the Golden Triangle, at the border of Burma and China’s Yunan.
The 7th arc cuts through there. That is some of the most lawless territory in the world. The Asian Triads derive their wealth/power from there. The peoples are Panthay (Burmese) and Hui (Chinese) Sunni Muslims.
When tracing flights on radarflight24.com the lines get black because there is no coverage…just an estimated path. You van see that many international flights take that exact route all day, everyday.
Same for QZ8501 when it passes through the non-radar gap…where it disappeared. That’s where the black line is visible.
Interesting.
@JS:
You are exactly right. It may be that what’s ‘routine’ about AirAsia is that they have (significant) operational issues:
The Age: Holidays thrown into chaos after AirAsia cancels direct Bali flights
December 27, 2014
http://t.co/XBd5WeMqHl
Sorry — that was easterly, not westwardly…and east/northeasterly, not west/northwesternly.