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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."
Sometimes big airliners can get lost at those.
SJW's don't eliminate discrimination. They just expropriate it for themselves.
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"
Of course the US has satellites that can look at that part of the world. And they may well be doing so. It's just China is trying to score a couple of PR points by showing that they can act like a Big Important Country and task their surveillance satellites to suit their interests.
We of course know that they can - spy satellites don't do much good if you can't spy on people. The US is also spending assets in the search. So will everyone else who is involved.
Faster! Faster! Faster would be better!
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.
Why do they not have satellite location based reporting on the planes providing the planes position every five minutes? Expand the ACARS system to give the position of the plane. This would help the searchers narrow down the location where the plane was lost.
I was thinking about this yesterday. Doesn't the vast majority of modern aviation tracking radar systems depend pretty heavily, not just for identification but for returns at all at at long distances, on the planes own IFFtransponders for replies?
http://en.wikipedia.org/wiki/S...
Could it not "drop off" the long range radar simply by turning off it's transponder? At that distance the radar return might be low enough that without the transponder response, it'd "disappear"...
Sure thing?
http://en.wikipedia.org/wiki/Over-the-horizon_radar
.
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
IANAATC, but...
Most center surveillance radars have a range of 200 - 250NM (ARSR-3, ARSR-4, AN/FPS-117, AN/FPS-67B). Secondary beacon radars have a range of about 190NM for 1090ES equipped transponders.
You are correct in assuming most high altitude center control ops, for aircraft in cruise, rely heavily on MODE-S data. This is transponder data and not primary radar echo return data.
Terminal radar, the kind you see at your local airport, mostly relies on primary radar data. But at a shorter range (~50NM).
The reasons for the difference are many, but come down to accuracy and overlap. Center controllers use a mosaic of data from multiple radars that must average primary returns, this leads to slight disagreements on the true location of the aircraft. The MODE-S data is constant though, so it is preferred. In terminal environments, there's usually a single radar set. So the primary data is more useful in terms of accuracy for spacing the aircraft (they can pack them in tighter more safely). Terminal radar sets also have a higher scan rate.
MH370 was over the Gulf of Thailand and was under coverage of about three different radars. Even if the transponder was turned off, primary return data would still be available for the track. CrimsonAvenger has a valid point, but the last known location of the flight was far off shore and at a cruising altitude. So we could possibly speculate that line of sight was not a big factor.
There's a lot of big mysteries and speculation at this point, but we just need to give it time. They will eventually find the wreckage and hopefully determine they cause. There are many historical crashes that required more searching than has been applied to MH370 (AF447). In the meantime, grab some popcorn and enjoy the conspiracy theories...
Time periods? Polar Bears? Smoke Monsters?
I disagree. The plane is hidden on a deserted volcanic island that's part of the Lesser Sunda Islands in Indonesia.
The planes occupants (including Mik Kanrokitoff) are currently aboard a flying saucer. Most will reappear in due course suffering from amnesia.
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).
The planes are not tracked by simple radar, but by responses. If it stops responding, and is not close to an airport, it is lost.
It will be found, but the sea is big, and they did not have the courtesy to plummet from the last known location.
The pilot that you're talking about was an awesome guy that frequently posted on flight sim forums, posted youtube videos about how to save you money on your air conditioner and had a daughter, a family. He was a better human being then you'll ever be.
OK, You win.
How soon can you implement changeover?
Don't let THEM immanentize the Eschaton!
I'm somewhat familiar with the RAT system and I'm not discounting it.
What I'm saying is that we must have had multiple system failures. ALL power or ALL hydraulic pressure (both of which have multiple redundant and independent systems) or possibly an unfortunate combination of partial system failures. Such catastrophic failures should be vanishingly rare, and usually would be the result of a major structural failure and one would expect the breakup of the aircraft would result. In flight breakup didn't happen or we'd have found this thing by now.
I have two primary theories at this point. First, it's possible there was a windscreen failure or small structural failure near the cockpit that leads to decompression. In the confusion the crew fails or is unable to get their O2 masks in place within the 10 seconds they'd have at 35K feet. If they where flying manually or disconnected the flight director somehow (pushing on the yoke or peddles would do this) the aircraft could fly for quite awhile and end up way off course. As we where almost 2 hours into the flight, it's even possible that only one pilot was in the cockpit. My second theory is that there was an intentional crashing, either by hijacking or suicide. In any case, the aircraft flew for awhile after the incident and impacted the water well away from their expected location generally in one piece.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Could it be that when emergency strike the crews panicked and started praying on their knees to their Allah and forgot to call for help ??
No. As my flight instructor told me, fly the plane first and if you have time, talk on the radio. If they where busy with multiple system failures the first task is to get control of the aircraft. If you don't have the aircraft under control, talking on the radio is the absolute WRONG thing to be doing unless there is time. ATC is required to ask you all sorts of useless questions and if you are struggling to control your aircraft the last thing you want or need is another distraction. "Nature of your emergency?" "Number of souls on board?" "What are your intentions?" Now if they can help you by suggesting the nearest airport, clearing the runway, getting the fire trucks rolling or getting search and rescue started by all means, get on the radio, but the first thing you do is FLY THE AIRPLANE.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Malaysian military radar's last signal for what they believe was this flight was over the Straight of Malacca. More specifically it was roughly 300km NW of Kuala Lumpur. The radar signal that showed the plane possible turning around was roughly 750km NNE of Kuala Lumpur.
If that is true, it means the plane banked port, crossed over Thailand and was probably trying to return to Kuala Lumpur. It likely also touched down on water in one piece and became submerged with a limited debris field. I'm thinking that they'll find it by Friday, submerged in the Straight of Malacca, in mostly one piece.
"Lack of speed can be overcome. In the worst case by patience." --Znork