You're still ignoring the issue.

I don't give two hoots what someone's "provisioned capacity" is.

Even your beloved NASA TDRS doesn't have the SPARE capacity for live telemetry from all aircraft. So please, give it a rest !

Here, I'll even quote you a NASA 2014 report (IG-14-018) on the very subject, I have highlighted the key phrase :

Mcdunav: Should not the possibility of the plane crashing in the Belitung forests be considered?

Start with the known location of loss of comms. Take max possible a/c airspeed, and known fuel reserve to determine the furthest the aircraft could have flown from the LKP, and draw a circle of that radius centre on the LKP. In principle the a/c could have come down "anywhere" in that circle.

Now get as much information from primary radar as possible, and any other credible data source, and narrow down the area within that circle to give a starting area to concentrate the initial searches for the available search resource - if those initial searches fail then widen the search area. Resources are not infinite. Time is important but you have no control over how long the searches will take irrespective of the media clamour for "information". Make sure that you spend your time trying to get results and not wasted on chatting to the media....:)

Also, FL360 may not have been available to due crossing traffic ahead.

@mcloaked
 

the current search area already extends beyond pulau Belitung so I thought that the search should also be extended to land. I have just read somewhere that this has indeed happened. The search area has now been extended to land.

Fwiw i just happen to have been on jakarta the day of this accident.

We have had thunderstorms all week but this one which passed overhead us was by far the worst by a significant margin.

Thats is a totally anecedotal comment with no intended necessary relevance to this accident it was just noteworthy that this was a pretty severe thunderstood by local standards.

A few pages back, the Indonesian SAR briefing states the following time line:

5.36 Airbus A320 flight 8501 departs Juanda

6.12 contacts Jakarta, requests weather deviation to left of M635 Airway and
climb to FL380

6.16 still observed on radar

6.17 radar contact lost, only ADS-B signal remained.

6.18 all contact lost

Some posters wonder why no distress call was made. The priority of the pilot is to fly the aircraft and if time permits, to call a mayday. Clearly, time did not permit.

Even though it was daylight, the aircraft may have been IMC, the weather radar in the cockpit inadequate, so difficult to dodge what appears to be horrendous CB embedded enroute. How likely is it that if correct measures were taken by the Captain to fly safely through what is common weather in these latitudes, that the aircraft would have broken up?

Cozmo,

Interesting typo in the third bullet of your slide on thunderstorm penetration do's and don'ts.

"Do maintain constant altitude. Allow the altitude and airspeed to fluctuate."

http://www.pprune.org/rumours-news/5...ml#post8800720

Sorry, I think you mis-read the article. It contains no reference whatsoever to spare capacity, but to replacement satellites to maintain service as the fleet ages. I'm not saying live telemetry is good idea, just that there are already satellites up which could handle that using a tiny fraction of their existing capacity.

what diff ?
 

@training wheels
don't understand what makes diff if B777 or A320? :ugh:

In 777 - and most other BA planes, pilot has final authority over computers etc by simply pulling or pushing or turning control wheel- which backdrives other control wheel. And has minimum cable controls when shtf.

Sidearm controllers don t work that way

But at this time not worth speculating . . .

As a pax I am somewhat disconcerted that the position of impact hasn't been located after two days. Although improbable, in principle there could be survivors in life rafts waiting for rescue. On radar, transponders working, reasonably busy part of the world. Does give suspicion that reassurances about the adequacy of current location systems may not be sufficient. Surely we should expect better than this? OK the facts may eventually show peculiar circumstances but that a/c was being tracked.

More moronic journalism

» AirAsia CEO Dumped Shares Days Before Flight Disappeared Alex Jones' Infowars: There's a war on for your mind!

How hard would it be to have a hydrostatically released ELT? It sure would make finding the wreckage easier. These have been on boats for decades now and IIRC the AAF had something like that on some bombers in the Pacific Theater in WW II.

Forgive me for stating the bleeding obvious but weren't we here a year ago with disappearing aeroplanes? We're perfectly capable of tracking something as large as an airliner but don't learn the lessons. Or perhaps we haven't lost enough aircraft in busy airspace yet ( interesting how when a plane disappears it's over 'miles and miles of ocean' but when I'm flying there I'm fighting for my level!).

38000 feet to ground level is a long time, plenty of time to make a call regardless of the situation at hand

Not very likely. Also I watched weather animation on weather channel showing how the systems were moving, the actual weather around this aircraft wasn't as bad as some portray it here on outdated weather photos.

I would like to point out to some of the newer posters...


why can't we track planes? well, I was watching CNN the last two days and they couldn't keep telephone guests online...the phone was invented about 140 years ago or so and we still can't keep a phone line up to allow an interview. SHOULD we spend millions of dollars for better phone lines?

ITS all about money. Are you willing to pay X amount MORE for your ticket if the plane has a 1 percent great chance of being found in 3 days after a crash?

AS to survivors in life rafts waiting for rescue. During WW2, many survived for WEEKS in life rafts before rescue. IT SHOULD BE NOTED that many if not all life rafts may have flare guns, signaling mirrors and ELT transmitter. I certainly am NOT privy to the exact equipment on this airliner, perhaps others can help us on this .

I do not think there are survivors in life rafts as they would be trying to signal if they possibly could.

BUT we may get lucky and find someone. And I am praying that they do.

continueapproach737
 

You weren't there. You have no idea what was going on in that flight deck or the situation that they faced.

Given the Xpdr etc was lost about FL290, I suspect the radios were not much use.

As others have said, there is no point in making a distress call, unless the person on the other end can act on the info and help your predicament. Contrary to the movies, reaching for the RT switch should be well down the priority list. Apart from anything else, it takes out 1 crew member answering the interminable questions :{

Sidearm controllers
 

Sampublius,

As you say [Airbus] sidearm controllers don't work that way but there are 'active sticks' out there that act like a physically linked pair of sidesticks. The new Gulfstream G500 and G600 will have them. Being new to the civil market there will be a cautious approach to them but I believe there will be increasing pressure for all sidesticks to be active.

Aviate, Navigate, Communicate....

Neither have you. Nobody has a clue what this crew faced but it doesn't help by posting incorrect weather images that are supposed to add 'drama'.

"Given the Xpdr etc was lost about FL290"

VHF line of sight range at FL320 is ~219 miles; may have dropped below line of sight?

What would they say?
 

AFR447's crew had 3.5 minutes, but never mashed the mic button...

Quote:
"38000 feet to ground level is a long time, plenty of time to make a call regardless of the situation at hand"


AF447 crew plummed out of the sky for 4 and half minutes before crashing in the Ocean .. any mayday in a such situation is going to be the last thing the pilots will think about. You fly the plane and try to do the possible and the impossible, it's a powerful instinct, our brain doesn't get stuck in a cognitive process when life is in a such danger.

Porterhouse
 

If that was directed at me - I haven't posted a single image. Nothing I say is intended to dramatise or sensationlise this accident. We have enough spotters, simulator gamers and conspiracy theorists on here for that.

Many people here, not pilots I may add, think that the priority of emergency procedures in an airliner is to keep people on an internet board informed as soon as possible. The number one priority of the aircraft design, the procedures design and the crew dealing with the emergency is to AVOID a crash. Leaving an information trail is not a priority, that is what the CVR and data recorders are for. When you hit a patch of ice in your car what do you do? Call An ambulance as the car is still moving? Start filming on you mobile? No, you try and drive out of it. Only when you have stopped and assesed if there are any injuries you call an ambulance and only when the ambulance has taken the injured away you take photos for your insurance claim.


Aircraft are not designed by idiots,;beleive it or not they are designed, like all machines with certain compromises, by people that know their stuff.

We will find out what happened here and we will change whatever needs changing to avoid a re-occurrence. Real time sattelite data downlink, not needed. It would not have ovoided the crash and the data will become available when the boxes are found. Calling ATC? At the bottom of list of priorities when your AC is out of control. What can they do to help? Fly the AC for you?

What we know isn't much but is definately painting a picture

sigmet active for emeded TS to FL500

Deviation requested to the left and climb to FL380 (from FL320) to avoid weather

Last ATC plot was climbing through FL363 with a slow 353kt G/S (aprox 200kts IAS)

?????, this aircraft was being tracked, right until what ever happened, happened. Primary and secondary radar.

"We're out of control!" "HELP!"
 

Phew! Sense at last.

Try calling ATC while actively dealing with a full-on emergency in the simulator and you'll be strictly admonished (b....cked) by the examiner as a matter of course. And rightly so.

And when in the dwang for real, "Mayday" means "m'aidez" = "help me". What help can ATC offer?

Answers on a postcard.......

(When in control having addressed the emergency, and with time allowing, once the actions have been performed, then it is time to let ATC know what you are up to)

Radar MEL
 

Lucille, does this mean a plane can be dispatched for a week without operating radar, even in a storm environment as existed in this case?

Oh, thanks for that, RoyHudd ... so that's my career completely wasted. :(

Although I do completely understand where you're coming from ... Aviate, Navigate, Communicate.
But - does pressing the Tx button involve that much distraction from the acknowledged essentials? Perhaps it does?

I only ever had one airborne emergency, in a Piper Colt, and one of the very first things after "Aviate" was to whimper "Pan". But then I was only a PPL student at the time, and someone in the circuit landed to get an Instructor up to the Tower ... :mad:

.... THAT THEY SHOULD READ THE WHOLE THREAD BEFORE POSTING THE SAME QUESTIONS AGAIN AND AGAIN.

Ahem, cough, sorry something was stuck in my throat there..... :E

RoyH is correct. ATC is last priority unless it is an ATC related problem.

On the speculation that this aircraft stalled; discounting wind, the 353knots ground speed equates to approx 167KEAS and 172KCAS.

This is not a stall speed for the A/C weight of approx 59 tonnes and roughly equates to where you would expect the airspeed to be in a high alpha situation being managed by the FMGEC.

There was about a 20 knot tailwind at the altitude the aircraft was flying at. Whether this can be factored in depends on whether the aircraft actually entered a CB, as the local wind speeds in the up draught and down draughts would render the calculation moot.

The 353 knot radar groundspeed (if accurate) probably means that the aircraft was very slow, but not stalled.

It is indeed about money. But, think about it this way. Governments and businesses have already spent many, many tens of millions of dollars on the MH370 SAR operation [1].

In my opinion, the argument "improved tracking ability would benefit less than 99% of flights, so therefore we shouldn't invest in it" is NOT a strong argument. We can quantify *precisely* how much should be spent on an improved tracking ability because it is a given that some number of planes will be lost.

Even if we only lose a plane once every 5 or 10 years, many millions of dollars are spent on search and rescue by various entities, and we also must include damages and potential losses for airlines, plane manufacturers, related business and industries, etc.

So if the search for lost planes costs $1B per decade, economics dictates we should then simply spend up to $1B per decade on preventing planes from being lost. Even if that investment wouldn't actually save the lives of passengers, it would reduce SAR costs, reduce risk of accidents during SAR operations, reduce grief of affected family, and also have side effects such as bolstering the perception of travel in the media and reduce any public fear of flying.

[1] MH370 search: Australia has spent far more than Malaysia | World news | The Guardian

MMEL says Weather Radar "May be inoperative provided weather reports indicate that no thunderstorm or other harzardous weather condition which can be detected by weather radar exist enroute."

Without any basis of fact I, like everyone else, is "assuming" that this is a weather related incident. Specifically, a possible inadvertent cell penetration.

So here's my pet peeve regarding the serviceability of weather radar.

Most MEL's allows for the weather radar to be unserviceable for 10 days (Category C) albeit with certain exceptions. These exceptions are open to interpretation.

And as we know, whenever there are commercial pressures, interpretation of any exceptions pertaining to safety never ends well for the crews.

The MEL for Radar needs to be changed to Category A. And the exceptions tightened up to minimize a "relaxed" interpretation for commercial reasons.

The thing that really angers me is that in contrast, the CVR, which does absolutely nothing for the immediate safety of the aircraft in which it's installed is allowed to be unserviceable for only 3 days.

Every MEL I have flown under adds to the above that the MEL may only be used if there is zero chance of convective weather along the route of flight. I think a 10 day MEL with the above restriction is reasonable.

Whatever category the WX radar would be, no MEL should substitude proper AIRMANSHIP. Especially in that area full of monsters with top higher than many airliners max ceiling.

Last GS was 353kts, maybe the plane wasn't stalling at that time... But what about a few second later, inside the cell, in a shear, turbulence, icing crystal condition...?

Probes blocked by ice maybe, loss of control due to shear very close to rec max alt. And speed tape so narrow, sudden unusual attitude followed by improper recovery technique..

Just my two cents, not speculating but recalling past accidents.. Wishing all the best to the SAR team and condolences to the families..

...and YES, communicating is last thing and quite useless if you are falling from the sky...

Or was the sale of stock by CEO of Air Asia a planned sale of insider stock announced quite some time ago?
On another note, I find it less than amusing; the frequent bashing of posts here of those unwashed and ignorant masses of lowly journalists, PC sim gaming pilots, self loading freight, etc, who dare to post their thoughts or opinions in this lofty realm of "Professional Pilots". To my knowledge, non of those bottom feeders have ever flown perfectly good airliners into terrain or bodies of water, never tried to race thunderstorms to an aerodrome with a full cabin of paying passengers merrily riding along. Non of these disrepected classes of fools have killed a single fare paying passenger with acts of egregious idiocy or outright recklessness. Plenty of sometimes well respected and experienced professional aviators have. There rant over.....:D

Satellite Available Bandwidth

It is dangerous in any technology field to say something is impossible.

Check INMARSAT latest offerings for broadband internet to passengers Inmarsat S-band services - Inmarsat
Check their new connectivity for ATM services SwiftBroadband - Inmarsat

Iridium Next is also adding broadband links https://www.iridium.com//About/Iridi...echnology.aspx including importantly 'short burst data with bandwidth on demand'

Tracking

That brings me to the repeated posts on Tracking. Both INMARSAT and Iridium Next are offering a free tracking service. This is for aircraft carrying ADS-C (that is Automatic Dependent Surveillance - Contract over Satellite links). All widebodies are equipped for this from the factory, even if the operators turn the equipment off it is standard fit. It provides more than ADS-B and is usually transmitted at 4 or 10 minute intervals. After AF447 the French BEA asked for the transmissions to be increased in regularity. This was avoided as beancounters in the operating companies did not want to pay the cost. As the SATCOM companies are providing it FREE there is now no excuse not to regularly pass ADS-C reports (which can contain a lot more data than just position and altitude.

It is mandated in many areas for aircraft to broadcast their position at up to twice a second on Automatic Dependent Surveillance - Broadcast (ADS-B Out). This is line of sight transmission to ground systems and other aircraft. In this case the aircraft WAS broadcasting its position. The air traffic unit will have stopped receiving it if the aircraft was below the horizon (below line of sight) or the power failed in the aircraft.

Emergency Location Beacons
These ELTs are carried by large numbers of aircraft both fixed and portable. In most cases the fixed beacons have a g-switch and the portable beacons an immersion switch that activates them. They broadcast mainly to 406Khz and give aircraft ID and position. Note people they already exist. However, if the aircraft sinks and the crew have not deployed life rafts with ELTs then the ELTs will not be able to send radio transmissions through the water. There are several military aircraft that have deployable external ELTs that would float. Needless to say the beancounters have not gone for these on commercial aircraft. Standard response: How many aircraft have been lost at sea that would have been helped by an ELT in the last 10 years? How many flights have there been in the last 10 years? What is the chance of one of our aircraft being one of those 3 or 4 that might crash in the next 10 years? Have you seen how much these things cost and the life-cycle maintenance cost? Go away.

So to sum up-
There IS sufficient satellite bandwidth to send DFDR/CVR data but probably as a short burst when the aircraft thinks it has a problem rather than a continuous download.
There are already tracking systems on aircraft that can provide accurate positions all the way to the surface - but no compulsion for the airlines to switch them on despite the satellite comms providers providing the tracking as a FREE service.
There are already methods of auto deploying ELTs when an aircraft crashes on land or in water, but only the military have fitted them to aircraft.