Look at the size of the search regions in the Indian Ocean and along the Australian coast in response to Malaysian 340's disappearance. Those are relative small lakes compared to the entire Indian Ocean, but they're still massive swaths of water.
Don't underestimate the difficulty of a SAR operation, especially at sea.
Why is it that we can track boats with satellites but not planes? In fact we have a complete image[1] of boat activity in the area at the time of disappearance.
It seems as crazy to me as how we can offer in-flight satellite-based wifi but not GPS tracking.
Boats are tracked by their AIS beacons on board, not passively by radar. The beacons can be switched off or stop working just the same as the beacons on planes.
Like another commentor here I don't have a huge amount of trust in early media reports but what I read was that it was within radar range when it disapeared.
lets also not forget that there is a substantial presence of military fleets in the area, all equipped with radars etc if it was anything other than a crash they'd have noticed.
The article says it disappears from radar. When tracking aeroplanes there are two kinds of radar primary and secondary. Primary is actual radar, secondary isn't really radar at all but instead radio transmission of telemetry such as position, altitude, speed etc. This is equivalent to AIS, the system used to track boats that produced your image.
So we were tracking the plane but then the plane stopped transmitting tracking info for some reason (no idea if they even had it on primary radar). Someone could have turned it off or the plane could have crashed.
> Why is it that we can track boats with satellites but not planes?
Satellites don't track either ships or aircraft, except for huge nuclear-powered RORSATs that watch the fleets of rival superpowers.
However whilst many trans-oceanic aircraft do have VHF / UHF datalink uplinks through the Inmarsat satellite network the majority use line-of-sight UHF transponders ( beacon-tracking ) to supplement radar ( skin-tracking ):
Transponder interrogation is often referred to as "secondary radar" but that's a misnomer that unfortunately took hold in the industry. It relies on 'squitting' a generated response, not on reflections from the aircraft structure.
Starting my 48-hour media blackout around this topic. If I've learned one thing from trying to follow aviation incidents, it's that almost everything popularly reported in the hours after the incident is either wrong or lacking important context.
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[ 3.5 ms ] story [ 65.5 ms ] threadDon't underestimate the difficulty of a SAR operation, especially at sea.
Oh wait. Flight number is 804: 8 + 0 + 4 = 12
66 people aboard: 6 + 6 = 12
Must mean something!
str('66') + str('6') = '666'
it's the devil.
It seems as crazy to me as how we can offer in-flight satellite-based wifi but not GPS tracking.
[1] http://i.imgur.com/XYvC5gI.jpg
So we were tracking the plane but then the plane stopped transmitting tracking info for some reason (no idea if they even had it on primary radar). Someone could have turned it off or the plane could have crashed.
They should position the tracking hardware outside the plane making it relatively tamper-proof mid flight.
Satellites don't track either ships or aircraft, except for huge nuclear-powered RORSATs that watch the fleets of rival superpowers.
However whilst many trans-oceanic aircraft do have VHF / UHF datalink uplinks through the Inmarsat satellite network the majority use line-of-sight UHF transponders ( beacon-tracking ) to supplement radar ( skin-tracking ):
https://fr24.com/2016-05-19/00:28/12x/MSR804/9c0b766
Transponder interrogation is often referred to as "secondary radar" but that's a misnomer that unfortunately took hold in the industry. It relies on 'squitting' a generated response, not on reflections from the aircraft structure.
https://www.reddit.com/live/wy0st0j6out0