Indonesian aircraft missing off Jakarta
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And an hour later, did it *still* show the airplane having landed, or had it replaced the data predicted in error with the correct data as received? I would expect the latter. But more to the point, I could see perhaps an writing an algorithm which predicts an airplane to have landed, when it notes that it is on a straight descending path pointed right at a runway, and if the airplane goes missed instead, it might take a few received data points and some data processing by the software to discover that the landing prediction was in error, and correct that. It seems a lot less likely that someone would write a predictive algorithm which would "predict" an airplane maintaining 5000 ft MSL and 300 knots, plus or minus random excursions either side of both parameters, for 6-ish minutes, when in fact the airplane did something completely different.
When you view the flight later or download the raw flight data it is only the received data, there is no estimated flight data.
Something surely must have failed or fallen off ... nothing else makes much sense.
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An aircraft can stall at any speed! It is the angle of attack which determines when stall (pitch angel) if they had flew at 350kt they would stall anyway if the nose was 40 degress nose up. A passenger airplane is is not designed nor have the trust required to do that, a rocket is a different thing.
i cant remember exactly how it is but if your static or pitot ports are blocked (either one) your airspeed will increase with altitude. So if they put on the autopilot after take off the plane will pitch up and up to contain the airspeed increase and rather quickly put the aircraft in an unusal attitude, nose high low airspeed (actual airspeed). Autopilot will disconnect and stall warning alarms etc. If the pilots dont react quicly and correct the airplane will stall. There might be a startle factor for the crew as well, which delay their reaction time. This only speculations from my side anyway. Tragic to see another fatal accident in Indonesia.
If you don't like it - go away.
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Jon Ostrower has an interesting analysis over at The Air Current which notes that there are at least three different versions of that Aircraft Flight & Maintenance Log circulating in social media:
The chilling concern of this is not only that documents are changing in different iterations on social media but that a signed maintenance document mightve been modified in some fashion to include a corrective action after the fact.
https://theaircurrent.com/aviation-safety/the-perilous-unreliability-of-lion-air-logs-floating-through-social-media/
While he correctly points out that sometimes purported relevant documents posted on social media are fakes I would also observe that the pictures of different versions of the pink maintenance page are not necessarily inconsistent with the workflow of a maintenance signoff.
A lot of folks take pictures of the signed paperwork these days for CYA purposes, these pictures could be a shot of the inbound squawks and another of the page with the work signed off.
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Not a Boeing guy, but this thread caused me to wonder the same thing, so I went googling. It appears that the 737 does have a trimmable stabilizer actuated by a jackscrew.
Please not. Let the Boeing redesign and service changes be the solution we all thought it was.
The underwater locator beacon has limited range so there is a need to start the search close to the wreck, we learnt that from flight MH370.
Mjb
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Well there was a loss of energy, but there was a gain in speed (and you're right about your inference, under the assumption of ~1G, of the very low likelihood of stall). In a discussion like this it's particularly important not to say "energy" as a stand-in for "kinetic energy." Normally that's a nitpicky pet peeve of mine, but here it actually matters as it introduces an ambiguity in a central area of the discussion.
Ostrower's article is here:
https://theaircurrent.com/aviation-safety/the-perilous-unreliability-of-lion-air-logs-floating-through-social-media/
While he correctly points out that sometimes purported relevant documents posted on social media are fakes I would also observe that the pictures of different versions of the pink maintenance page are not necessarily inconsistent with the workflow of a maintenance signoff.
A lot of folks take pictures of the signed paperwork these days for CYA purposes, these pictures could be a shot of the inbound squawks and another of the page with the work signed off.
What is CYA?
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ATC
Did they at any time declare an emergency?
The authorities said they aircraft requested ATC to return and no further contact afterwards. With the Fr24 data available we can see the situation was serious very early in the flight, surely a full emergency would have been declared.
Yes, I know, fly first talk later but there must have been concern on the ground and some attempt at communication.
The authorities said they aircraft requested ATC to return and no further contact afterwards. With the Fr24 data available we can see the situation was serious very early in the flight, surely a full emergency would have been declared.
Yes, I know, fly first talk later but there must have been concern on the ground and some attempt at communication.
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Well there was a loss of energy, but there was a gain in speed (and you're right about your inference, under the assumption of ~1G, of the very low likelihood of stall). In a discussion like this it's particularly important not to say "energy" as a stand-in for "kinetic energy." Normally that's a nitpicky pet peeve of mine, but here it actually matters as it introduces an ambiguity in a central area of the discussion.
Does it not?
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What is CYA?
Cover- Your- A*s
If Maintenance say "you're good to go", well take that with a grain of salt. Put a snag in the logbook, call maintenance so they " know" you have a snag in the log, then they have to answer it, consult the MEL, and sign off the snag with a signature. Then a copy is in the system, plus there is a answered snag in the aircraft logbook.. Or wait for a part/repair before the aircraft is good to go.
Always keep a copy , if you can of any irregular ops , ie datalink messages from crew sked, "you are legal to fly an extra leg" or whatever..
Cover- Your- A*s
If Maintenance say "you're good to go", well take that with a grain of salt. Put a snag in the logbook, call maintenance so they " know" you have a snag in the log, then they have to answer it, consult the MEL, and sign off the snag with a signature. Then a copy is in the system, plus there is a answered snag in the aircraft logbook.. Or wait for a part/repair before the aircraft is good to go.
Always keep a copy , if you can of any irregular ops , ie datalink messages from crew sked, "you are legal to fly an extra leg" or whatever..
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[QUOTE=Volume;10295496]If airspeed is unreliable, it does not matter that it indicates the aircraft is going fast.
Unreliable might mean too hig, unreliable might mean too low, for sure unreliable means neither the pilot nor any speculations should rely on it...
This is the part that doesn't seem to make sense. VMC/Day. Plenty of fuel, lots of time to work the problem?
Are we missing something here?
Unreliable might mean too hig, unreliable might mean too low, for sure unreliable means neither the pilot nor any speculations should rely on it...
This is the part that doesn't seem to make sense. VMC/Day. Plenty of fuel, lots of time to work the problem?
Are we missing something here?
[QUOTE=Volume;10295496]Anyway, the aircraft took of around 90 Minutes after sunrise in good weather. Quite different from Birgenair or AF, there was clear visual reference all the time. Good pilots could handle aircraft under such conditions even after full loss of instruments...
This is the part that doesn't make sense to me.
Are we missing something here?
This is the part that doesn't make sense to me.
Are we missing something here?
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Do FW training schools not teach manual control manipulation? Day, CAVOK, setting a power figure you know is cruise or whatever profile you require. Fly the attitude!
Compass and GPS Ground speeds and heights are not pressure tube connected. BASICS are missing from todays Hi-Tech 'Auto-Pilot' Eerr what's it doing now lah, crews. Air France 447 plus a few others recently.
Compass and GPS Ground speeds and heights are not pressure tube connected. BASICS are missing from todays Hi-Tech 'Auto-Pilot' Eerr what's it doing now lah, crews. Air France 447 plus a few others recently.
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No, it drops off precipitously at the end, along with altitude as the speed shoots up. But more to the point, it's speed and not TE that matters for ~1G stall. You can haul any low-performance plane 45 degrees up and coast it into a stall, and the TE will stay about the same. I.e., you won't be able to tell what's about to happen from a TE graph.