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China Deploys Satellites In Search For Missing Malaysia Airlines Flight
EwanPalmer writes "China has begun using its orbiting satellites in a bid to find the missing Malaysian Airlines flight. The Xi'an Satellite Monitor and Control Center is said to have launched an emergency response to search for Flight MH370 after it went off radar over the South China Sea in the early hours of Saturday. The center is reported to have adjusted up to 10 of its high-res satellites to help search for the plane."
There's an auto-playing video embedded in the linked article's page - just in case you hate that sort of thing.
systemd is Roko's Basilisk.
Radar is line of sight. So a plane at 11000 meters, can be seen about 375 km away from the radar installation, assuming a radar at ground level.
If your radar is within 200km of the plane, the plane would fall below the radar horizon at about 5km altitude.
Given the description of the plane's flight path, if it was being tracked by radar from Kuala Lumpur, then "dropped off the radar" would have been closer to 10km altitude than to 5km.
"I do not agree with what you say, but I will defend to the death your right to say it"
Sometimes big airliners can get lost at those.
While that happens once in a while with US flights, I don't think there are very many airports in that lane where an errant 777 could go unnoticed. The route, as described on the BBC is a very heavily traveled air lane and the flight should have been easily tracked, particularly if it had veered off course.
No floating debris is perplexing as that should have been soon spotted had the flight broken up.
A feeling of having made the same mistake before: Deja Foobar
Another thought. How low does a plane need to fly to "drop off the radar"?
First, Civilian radar depends on transponders, a small transmitted signal from the aircraft that is triggered by the Radar signal. This transponder responds with a "squawk code" (a 4 digit number assigned by ATC) along with some other basic information like altitude. Transponders make it unnecessary to get a "primary" return (i.e. they don't have to get the actual radar signal return) for the aircraft to show up. In fact, most civilian radar installations run with primary returns filtered out because they create visual noise for controllers, because weather and other noise shows up.
Second, the aircraft in question was at the far reaches of radar coverage. This tells me that a primary return was unlikely. In fact, the radar coverage for this aircraft was expected to end right about where it did. I"m told that radar coverage did not start back up for the next controller for a few min of flying time so a short time out of coverage was expected. They will pull the tapes and review for any primary returns, but I'm guessing this has already been done an it provided little information.
So, this tells me that something happened to the aircraft during the short time it was outside of coverage. What ever it was, it must have disrupted the flight controls and likely their communications ability, but it seems that the aircraft stayed largely in one piece, at least until it impacts the surface. If it was generally in one piece with say the vertical stabilizer disabled it could have flown a LONG way from the last position report.
It did NOT break up at altitude. Something rendered the aircraft uncontrollable. A loss of hydraulic pressure or power does this for a 777. Decompression at 35,000 feet can do significant damage to an aircraft's systems, plus it can incapacitate the flight crew in less than 10 seconds. Decompression can do this, without causing the aircraft to come apart in the air. Metal fatigue, fuel tank explosion, small explosive device, uncontained engine failure are all possible things that can cause decompression and all of these have happened before.
My guess is that they will find the aircraft tens even hundreds of miles away from the last known position, largely in one piece under water. The longer this takes, the further away from where it was last seen it will likely be. This is because they have found nothing yet. Much of an aircraft floats, so it sank in one major chunk with out spreading debris too far. This is not totally inconsistent with past aircraft crashes. KAL 007 flew nearly 20 min in a slow descending circle after being shot down. They will find it in a day or two.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
So NOW do you see the advantage of a flat Earth?
A loss of hydraulic pressure or power does not do this for a 777. It has a RAT (ram air turbine) which pops out in such cases. Basically a big propeller which gets turned by the wind as the plane glides at 500 mph and generates enough power rudimentary electronics (including radio) and hydraulic pressure. That's what happened with the Gimli Glider - a 767 mistakenly loaded with insufficient fuel (the original boneheaded imperial vs metric conversion foul-up before the Mars Climate Orbiter). which basically turned into a 100 ton glider when it ran out of fuel mid-flight. The RAT popped out and allowed the crew to control the plane to a safe landing. (Which of course means if this did happen on MH370, the search area needs to be much larger than where they're currently looking).
Hydraulic failure usually involves structural damage which compromises all the hydraulic lines. Most commercial aircraft have 3 independent hydraulic systems; some have 4. If there's damage which severs lines in all of those systems, the plane can "bleed" hydraulic fluid until there's not enough left to control the flight surfaces. I believe the 777 used a hybrid fly-by-wire + hydraulic system though, where pilot commands are transmitted to the flight surfaces by wire, and a hydraulic pump there moves the flight surface. So severing the hydraulic lines may have killed one control surface, but not all. (Severing the wires OTOH...)
Anyway, I'm skeptical that it broke up at altitude too. That usually generates a lot of floating debris (papers, luggage, clothing, bodies, etc.) scattered over a wide enough area that the crash area is quickly located. The pingers should be firing away so it's just a matter of one of the search boats traveling within a few miles from the plane's resting location. (KAL007 wasn't located because the Soviets knew from their radar tracks where it went down, and set up decoy pingers far away to get the U.S. and South Korea to search the wrong location).
This aircraft had modern rolls royce trent engines - these come with an online 24x7x365 service back to Derby in the UK where all engines that are flying around the world are monitored in close-to real time using an independent comms facility to that of the rest of the aircraft. They will know if the engines powered up/down and what their status was at the last moments before contact was lost. I imagine the Malaysian Authorities are keeping a lot of the data under-wraps at the moment and I would assume that a lot more is known about the aircraft than is being released to the public right now.