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Air Asia Indonesia Lost Contact from Surabaya to Singapore

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Air Asia Indonesia Lost Contact from Surabaya to Singapore

Old 28th Dec 2014, 17:19
  #181 (permalink)  
 
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So a bit of patience before going into establishing " facts " and deducting wild theories .
So true ATC Watcher. Sadly, most of these people wouldn't have a life if they couldn't do that. The wilder the theory the more they get off with it. Sad.
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Old 28th Dec 2014, 17:20
  #182 (permalink)  
 
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Originally Posted by Downwind Lander
Apols if anyone has commented on this - MH370 taught the world that there is merit in flight data going to the FDR and CVR, but ALSO to an Internet based repository (- just in case). Can it be, almost a year on, that nothing has been done about this?
Much can very easily be done but the problem of course comes down to cost and a justification of what actual benefit such a thing provides. In terms of actual safety it provides no benefit at all bar letting investigators know what was happening to the aircraft before finding the flight recorders.

It costs a huge amount of money to maintain a satellite link and to therefore transfer flight data in real time, I really doubt it is possible to do so economically. Factor in how many aircraft are in the sky and all of them maintaining satellite links... That is serious bandwidth.

I hate to mention the worst but this plane will be found and occurances like MH370 are thankfully extremely rare to almost unheard of. Engineering a hugely expensive comms link for real time flight data transfer is just not necessary.
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Old 28th Dec 2014, 17:29
  #183 (permalink)  
 
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Originally Posted by Downwind Lander View Post
Apols if anyone has commented on this - MH370 taught the world that there is merit in flight data going to the FDR and CVR, but ALSO to an Internet based repository (- just in case). Can it be, almost a year on, that nothing has been done about this?
The Internet repository at FL350 is called satellite transmission. Lack of bandwidth and/or huge costs is your answer.
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Old 28th Dec 2014, 17:38
  #184 (permalink)  
 
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"This flight was on primary radar when lost. Hence this is nothing like MH 370."

so what else than midair breakup could happen to get lost from the primary radar? (provided it was not on the limit of radar coverage area)
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Old 28th Dec 2014, 17:44
  #185 (permalink)  
 
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Downwind Lander,

Pretty much as blue_ashy & Caygill have told you.

The limited number of scenarios, and the rarity of the instances in which said scenarios have/would/could occur is what makes is a pointless endeavor to have live data.

As blue_ashy & Caygill say, its not just the underlying technology, because its 2014 and so the technology is there. The problem is with the associated opex and capex.

The opex of building and certifying the system, the cost of the airlines to acquire and install such systems etc.

The capex of maintaining such systems, and of paying all those expensive satellite comms bills etc.

And of course, probably the fact that the limited number of satellites "up there" could probably not cope with the combined volume of data that would be generated by all the aircraft "up there". Its not like they can launch new satellites on a whim without yet more vast expenditure.

I suspect the manufacturers and satellite operators would find it easier to sell pork in a Kosher butchers than to convince their airline customers to roll out such technology across their fleets. Airlines are not exactly rolling in money, its a highly competitive business on wafer thin margins.... and I very much doubt the SLF will be willing to pay higher ticket prices.
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Old 28th Dec 2014, 17:51
  #186 (permalink)  
 
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"This flight was on primary radar when lost. Hence this is nothing like MH 370."

so what else than midair breakup could happen to get lost from the primary radar? (provided it was not on the limit of radar coverage area)
Low height. Electromagnetic waves as used to by radar follow quasi-optical rules, so limits imposed by the earths curvature ("below the horizon") apply here as well.
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Old 28th Dec 2014, 17:52
  #187 (permalink)  
 
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Caygill says: "The Internet repository at FL350 is called satellite transmission. Lack of bandwidth and/or huge costs is your answer".

Don't forget that the repository entry for each flight can be wiped and space recycled at the end of each flight.

An important point is that when something happens, the data is needed VERY QUICKLY INDEED or the exercise becomes one of salvage.

Question: What would be the percentage increase in overhead costs to the industry? [You may use the exponential notation]

Last edited by Downwind Lander; 28th Dec 2014 at 17:54. Reason: A
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Old 28th Dec 2014, 17:57
  #188 (permalink)  
 
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Don't forget that the repository entry for each flight can be wiped and space recycled at the end of each flight.
Three people have just spelled it out to you .....

Data storage would the cheapest part of the whole solution, infact it verges on irrelevant in the context of the other costs.

The main problem in terms of operational expenditure surrounds the use of satellite communications. Which isn't cheap, and will probably suffer from capacity issues if all airlines used it.

Pile the operational expenditure on top of the capital expenditure and you can see why your dream is destined to remain a dream. It simply is not workable from a financial point of view given the highly limited number of rare circumstances where it would be useful.
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Old 28th Dec 2014, 17:58
  #189 (permalink)  
 
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I would imagine there is a slight difference between a Cessna 206 and a commercial airliner flying at 35,000 feet across multiple countries.
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Old 28th Dec 2014, 18:04
  #190 (permalink)  
 
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This idea of "huge cost" of satellite tracking is surely nonsense,
Read what Downwind Lander is proposing.

He wants live streaming of telemetry data.
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Old 28th Dec 2014, 18:05
  #191 (permalink)  
 
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o
flt001

This flight was on primary radar when lost. Hence this is nothing like MH 370.
I'm sure you mixed primary and secondary radar. ATC works with secondary radar, which is the interaction of ground station with aircraft transponder, what you see on the scope is the signal information of the aircraft transponder.

Primary radar is an active ground radar and its reflected energy displayed on a radar scope.

The time where radar contact was lost points only to the point, where the aircraft transponder stopped transmitting. There are multiple reasons for such an occurance.

Last edited by RetiredF4; 28th Dec 2014 at 19:26.
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Old 28th Dec 2014, 18:07
  #192 (permalink)  
 
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Originally Posted by Downwind Lander
Caygill says: "The Internet repository at FL350 is called satellite transmission. Lack of bandwidth and/or huge costs is your answer".

Don't forget that the repository entry for each flight can be wiped and space recycled at the end of each flight.

An important point is that when something happens, the data is needed VERY QUICKLY INDEED or the exercise becomes one of salvage.

Question: What would be the percentage increase in overhead costs to the industry? [You may use the exponential notation]
As already mentioned, data storage would be the cheapest part and therefore is not the problem.

Getting live data from the aircraft down to a hard drive somewhere else in the world is the problem.

In remote locations, only satellite can be used to transfer this data and maintaining a constant satellite link for every aircraft in the sky is next to impossible to do economically and maybe even practically.

And of course this problem is one of salvage, having a live data stream would not deter the fact that this aircraft has crashed so it does nothing really for aviation safety bar solve a problem rarely encountered.
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Old 28th Dec 2014, 18:10
  #193 (permalink)  
 
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been there done that

Was in 747-100 cargo from syd-hkg same time frame nothing was painting on radar I went back to galley to get coffee as I came back up the captain said to strap in we hit a cell rising fast went from fl33 to fl39 in seconds and wild airspeed swings then back down to fl33 all three of us looked at each other and said what the hell was that? As a side note this aircraft was number 3 off the production line !
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Old 28th Dec 2014, 18:10
  #194 (permalink)  
 
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Weather was all bad

I flew just a few hours before this flight took off from Surabaya. Our radar was nothing but,skull and crossbones over most of Indonesia and the Java sea. Also to not. Jakarta radar does not depict weather. There ATC is 30 years behind at best. Coverage is intermittent. So, the likelihood of an airplane vanishing in this area is extremely high.
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Old 28th Dec 2014, 18:25
  #195 (permalink)  
 
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And UPS/FedEx seem t track their trucks. Having found "trackyourtruck.com," tracking seems possible on a large scale
Oh please !!

If you're going to quote an example at least quote a decent one in a similar environment (i.e air, sea ... or somewhere in deepest darkest Antarctica or whatever).

Quoting a ground based solution to an aviation problem is totally irrelevant and pointless.

Fedex, UPS, taxi operators .... they track their vehicles using M2M. And typically these days this operates over mobile/cellular networks. Maybe with failover to satellite, but not normally, because .... yep, you guessed it ... satellite ...is... EXPENSIVE ! So you'll probably only find that on those armored cash-carrying trucks etc.
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Old 28th Dec 2014, 18:28
  #196 (permalink)  
 
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Statistically speaking...

... any country losing 3 major aircraft ENR in a year is so vanishingly small as to be statistically impossible.

There have been 15 ENR losses of aircraft with more than 50 passengers in the last decade, and with 150 countries flying, that means each country had a 1% chance of losing an aircraft in any given year. That means one chance in a million of losing three.
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Old 28th Dec 2014, 19:02
  #197 (permalink)  
 
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... any country losing 3 major aircraft ENR in a year is so vanishingly small as to be statistically impossible.

There have been 15 ENR losses of aircraft with more than 50 passengers in the last decade, and with 150 countries flying, that means each country had a 1% chance of losing an aircraft in any given year. That means one chance in a million of losing three.
Except the aircraft that has gone missing is Indonesian. Air Asia is a franchise business.
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Old 28th Dec 2014, 19:02
  #198 (permalink)  
 
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because .... yep, you guessed it ... satellite ...is... EXPENSIVE !
Nonsense mixture!

The idea is live streaming of telemetry data ONLY in case of an emergency or suspect deviations from planned route, altitude, heading, speed, flight law, g factor etc. It would provide the exact coordinates of last transmission!
That's not expensive, just a tiny bit in comparison to the search effort already spent.
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Old 28th Dec 2014, 19:05
  #199 (permalink)  
 
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A320 drivers please...

on the A320, what's the data source for the Mode C altitude response? One of the ADIRUs or a single encoding altimeter? I see the control panel allows switching between two XPDR unit, presumably they are each fed from different altitude sources?
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Old 28th Dec 2014, 19:20
  #200 (permalink)  
 
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we hit a cell rising fast went from fl33 to fl39 in seconds and wild airspeed swings then back down to fl33 all three of us looked at each other and said what the hell was that?
So all you can say is the indicated altitude/level changed (same probably goes for airspeed).

Within a CB as well as the turbulence the pressure variations will affect readings on the pressure instruments.

Hence the advice to fly attitude and set power.
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