General Discussion
Related: Editorials & Other Articles, Issue Forums, Alliance Forums, Region Forums"It's impossible for an aircraft to evade radar"
I've heard this repeated constantly as an argument against a hijacking and redirection to another country. That it couldn't have happened because some country's military radar would have detected it.
If this is true, why don't we know exactly where the plane went down? How did it fly undetected for 4-5 hours? Why assume it couldn't have flown further undetected and landed?
itsrobert
(14,157 posts)n/t
B2G
(9,766 posts)Bjorn Against
(12,041 posts)You could also ask "Crashed where?" as well, but no one knows. At this point however I think it is more likely that it landed than crashed, the limited evidence we have suggests the plane was deliberately off course.
rrneck
(17,671 posts)I'm honestly trying to understand this.
rrneck
(17,671 posts)But if you plot a course due west or northwest from the last known location it's over water.
I'm no expert but I'm guessing there was a serious malfunction, maybe a cockpit fire, that disabled communications and the aircraft tried to turn back to it's point of origin. The problem got progressively worse before the turn could be completed and the crew tried to work with it as the plane carried them out of radar contact.
If there was a mechanical malfunction that damaged the control systems of the aircraft it could have resulted in a long turning arc that kept them over water in the Indian Ocean. The malfunction might have caused the aircraft to bank left and execute a slow turn that they couldn't correct. Or maybe the crew just let that problem go while they worked with other more serious concerns. That malfunction might have crashed the plane after a period of time beyond radar contact.
There was a 747 a while back that suffered catastrophic hydraulic failure and the crew had to steer the aircraft with the engines, adjusting power to turn. If the plane can't tell us where it is, and the crew can't control where it goes even for a short amount of time, it can be really hard and maybe impossible to find it. You can cover a lot of ground at four or five hundred miles an hour.
HereSince1628
(36,063 posts)that was lost as it left Malaysian radar coverage?
itsrobert
(14,157 posts)n/t
Blue_Tires
(55,445 posts)hack89
(39,171 posts)few countries can afford to cover every inch of airspace 24/7.
upaloopa
(11,417 posts)covered by radar. I was a radar repairman in the Army. Radar has it's limits. To cover the whole ocean there would have to be transmitters and receivers on the water all over the sea. That could be on platforms on ships or on planes like AWACS
B2G
(9,766 posts)Would it have been possible for the aircraft to fly undetected offshore and an altitude that would allow it to land in a hostile country?
upaloopa
(11,417 posts)countries have defensive radar
My guess is it was tracked by more than one radar but they haven't put all the pieces together. The radar could tell the size but not what the object was all except for ECM.
B2G
(9,766 posts)if it was picked up by a hostile country, I could imagine them not reporting it.
In fact, maybe they knew the plane was enroute all along.
Just thinking out loud.
upaloopa
(11,417 posts)If it was hijacked what was done with the passengers and crew.
B2G
(9,766 posts)If they didn't want a ransome, but the plane or something in the cargo.
One_Life_To_Give
(6,036 posts)Reality is you have a young person sitting day after day in-front of an antiquated radar unit. Over which not much interesting ever happens nor is there the means and will to do something when certain a anomalies occur. Thus when the military is on high alert and told to report every non-conformance no matter how small, much can be seen. When the human factor starts filtering what is reported there is much that becomes not significant enough to be noticed.
B2G
(9,766 posts)the military radar from countries who would have been within range of the projected path. So maybe they'll find something..
Renew Deal
(81,877 posts)From what I read, there are gaps in radar coverage.
upaloopa
(11,417 posts)Maybe it was hijacked and flown just above sea level
That's my guess. I think it was flown to a country that will not cooperate in it's finding.
I wouldn't be surprised if it is used in a terrorist attack. If on the ground it would have to be hidden because satellites could see it.
B2G
(9,766 posts)Flying at that altitude is very inefficient from a fuel usage standpoint.
At altitude, they had about 7 hours of flight time.
DanTex
(20,709 posts)BlueStreak
(8,377 posts)Just adding another crackpot theory to the list. Somalian pirates is as plausible as any of the other theories people are pulling out of their backsides.
SidDithers
(44,228 posts)once you're a good distance away from land, the curvature of the Earth shields everything below the horizon from land-based radar installations.
http://en.wikipedia.org/wiki/Horizon
If I'm doing it right, then the appropriate image is this one:
Where h is the altitude of the plane, and s is the curved distance to the nearest land based radar installation.
Solving for s, when h is 10km (assuming the Earth is spherical, with a R=6371km, close enough for this approximation) we get
s ~ 360 km.
So, any land-based radar installation can only "see" an airplane, cruising at 10km above the Earth surface, once it gets to be with ~360 km.
Range can be extended by raising the height of the radar installation. Putting the radar on the top of a 500m tower would mean you could see a plane at altitude 10km from about 440 km.
There's lots of ocean that's further than 400km from the nearest radar installation.
Sid
B2G
(9,766 posts)do you think it would be possible to fly offshore at an altitude long enough to avoid radar detection until it would be picked up by, say, Iranian or Pakistani radar and be allowed to land?
Malaysian officials have stated the aircraft had enough fuel for approx. 7 hours of flight time.
SidDithers
(44,228 posts)I don't think there are any gaps in radar coverage of the borders of Chinese airspace.
Sid
B2G
(9,766 posts)headed up toward the Gulf of Oman, avoiding land.
Don't know if 7 hours of fuel would get it there, but based on the map I posted above, it looks like it would.
We could probably figure it out by doing a series of great arc length calculations, plotted along an imaginary path from last known position, through intermediate points near the Maldives, and then up toward Pakistan.
But that's more math than I want to do
Sid
B2G
(9,766 posts)SidDithers
(44,228 posts)if you wanna plug in the lat/long of the starting point and finishing point, along with the initial bearing, you might be able to approximate the distance, and figure out if fuel load be sufficient.
http://www.movable-type.co.uk/scripts/latlong.html
Sid
hootinholler
(26,449 posts)File what follows under: "this person has no idea what the limitations of radar is let alone how radar is used for air Traffic Control and how that use is different from how radar is used for military defense."
B2G
(9,766 posts)it would have been rendered useless once the transponders were turned off.
Focus is in military radar at this point.
krispos42
(49,445 posts)With the transponders off, it's just a blip to any radar within range. No ID or anything.
Plus, radars have a limit based not only on the power of the radar, but on the altitude of the aircraft, the so-called "radar horizon". Radar is line-of-sight, so if the plane is low you have to be closer to the radar before it can see you; otherwise you're below the curve of the earth.
Not only that, but radars can be blocked by terrain features such as hills and mountains. This creates blind spots, sectors where the plane can't be detected.
If the plane was hijacked and the hijacker's pilot was experience, he could have flown fairly low to evade detection by all but the closest radars, and used terrain features (such as valleys) to mask the plane.
Finding a plane that doesn't want to be found can be difficult.