Malaysian airlines has lost a 777

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Dari

Lifer
Oct 25, 2002
17,133
38
91
iirc there was a mid air collision over Brazil a few years back as well

Yeah, that was because of incompetent ATCs allowing both planes (one flying east another flying west) to fly at the same altitude.
 

MaxFusion16

Golden Member
Dec 21, 2001
1,512
1
0
It's the pilots.

One of the pilots or both, hijacked the plane for some reason. It would explain the lack of a distress call, and they'd have the knowledge and access to disable the transponders.
 

TraumaRN

Diamond Member
Jun 5, 2005
6,893
63
91
I'm thinking if this plane was flying under radar coverage it could be anywhere. Hell it could have crashed on the island of Aceh in the dense jungle and be months until it is found.
 

mmntech

Lifer
Sep 20, 2007
17,501
12
0
I'm going with Langoliers, even though I'm sure that joke was probably made at least 5 pages back.
 

RaistlinZ

Diamond Member
Oct 15, 2001
7,470
9
91
It's the pilots.

One of the pilots or both, hijacked the plane for some reason. It would explain the lack of a distress call, and they'd have the knowledge and access to disable the transponders.

I was thinking that too. If the plane had 7 hours of fuel, that's a lot of territory that will have be searched.
 

pilotofdoom

Junior Member
Dec 11, 2007
11
0
66
You might be surprised that commercial airliners typically have a glide ratio around 3:1. That is, for every 3 feet forward glided, they will lose 1 foot of altitude. This of course will vary depending on what speed they started the glide, head winds, and other factors, but if an airliner is cruising at 36,000 feet, it could make 100 miles.

36,000ft*3 (glide ratio)= 108,000 ft
108,000/6076 (ft/nm)=17.7nm, which is not 100 miles.

Most aircraft are in the 7-10:1 glide ratio iirc. Just gotta remember to convert ft to nm. If your plane happens to be 6:1, makes the calculation easy since its basically 1000 ft of altitude equal 1nm glide. 9:1 is also nice, 1.5nm per 1k feet.

The only aircraft that get as bad as 3:1 glide ratios are helos, depending if they are trying to get max glide or minimum rate of descent. At 3:1 ratio, you are falling out of the sky quite quickly. At 9:1, you might actually get somewhere useful.

----------------
NikolaeVarius, thanks for your inputs.

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Other thoughts:

If the aircraft had a complete loss of electrical power, the jet engines should keep running until they run out of useable fuel, which maybe much less than fuel onboard if electric pumps feed the tanks that directly feed the engine. Jet engines typically have mechanically driven fuel pumps in order to prevent loss of power if electrical power is disrupted.

However, other systems may depend on electrical power for critical flight operations, and that is dependent on the specific aircraft model. I'm not spun up on the 777, but the idea is that a simple aircraft (ie Cessna 172) depending on bell cranks and pulleys doesn't need electrical power, but the moment you transition to fly-by-wire, you have a computer that needs electrical power from somewhere, whether it be generators, wind/APU backup generator, or a battery. If generators and backup APU/generators failed to come online, battery would give limited time. Most aircraft I've seen is about 10-30 minutes for that battery, depending on how large of load was placed on the battery. I would hope the transponder would be on the Essential Bus (powered by the battery), but that would only do good if the aircraft was within radar range. I am also ignoring other things that could be on the electrical buses, such as environmental, cooling, assorted pumps, switches, valves, etc, some of which may be critical to keep flying that are specific to every aircraft.

Radars- yes, ATC can pick up aircraft without a transponder operating, but only at much closer ranges than with an operating transponder. Think of it this way: at night, with your car headlights you can only see trees so far away. But then a reflective sign can be seen at significantly longer distances. Basically a transponder acts in similar fashion, though the analogy is not technically correct, since the transponder emits its own energy vice reflecting the radar energy. To disable a transponder, just gotta pull the right Circuit Breaker, probably labeled (in English jets) XPNDR. Every piece of electrical equipment on an aircraft goes through a CB, which means there typically 100+ of them.

Lost Comms - there are dedicated procedures for lost communications per the FAA for the United States. Its found in a publication that should be carried aboard every flight conducting IFR operations. Simplified instructions are: if clear of clouds (VMC), remain clear of clouds and land at nearest suitable airport and contact FAA. If in clouds (IMC), execute your filed flight plan shooting an approach at your destination at the time filed.

The way that would play into this accident, if the aircraft lost comms and navigation, but still had the ability to fly, the pilot likely turned back to Malaysia to get back to his departure airport on the West coast. Being a Malaysian Airline pilot, I imagine he'd be more comfortable going back there then continuing on to Vietnam or China. If I wasn't sure about the length of runways available, and without navigation, I would go a familiar airport, such as the departure airfield. To get there, I would hit the east coast of Malasia (not knowing exactly where on the coast), cross Malaysia, turning South to follow the coast to eventually reach the airport in Kuala Lumpur. (credit to benzylic, thought of the same thing). The biggest two issues I could think of arising from extended flight operations, 1-if an electrical fire started this mess in the beginning, it could have become a problem later especially if they were trying to bring systems back online, or 2, if they were unable (or forgot to), transfer fuel to the tanks that directly feed the engines and they flamed out. Of course, that's assuming no foul play involved.
 

Qianglong

Senior member
Jan 29, 2006
937
0
0
Vietnam despite being a relatively poorer country out of all those participating in the SAR, has put in quite a bit of manpower and whatever old planes they have to the mission. Impressed by their dedication!
 

norseamd

Lifer
Dec 13, 2013
13,990
180
106
Vietnam despite being a relatively poorer country out of all those participating in the SAR, has put in quite a bit of manpower and whatever old planes they have to the mission. Impressed by their dedication!

vietnam is a rising nation

what other countries are you talking about
 
Feb 4, 2009
35,209
16,667
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Holy crap the screen name, one post a year and the knowledge bomb epic. I was going to say its the Flying Dutchman but pilotofdoom is much better
 

quikah

Diamond Member
Apr 7, 2003
4,100
670
126

Qianglong

Senior member
Jan 29, 2006
937
0
0
Not anymore, suspending their operations. http://m.nzherald.co.nz/world/news/article.cfm?c_id=2&objectid=11218446

Seems that Malaysia has no clue wth they are doing, or they are trying to cover something up.

Well unless Malaysia can get their fact straight there is no point in wasting fuel and manpower on a wild goose chase. I read online that by the time vietnamese SAR planes get to the "crash site" they only have 20 minutes of fuel left to conduct the actual search! If Malaysia is really putting out false information or hiding stuff, all the countries should send them a big fat bill!
 

norseamd

Lifer
Dec 13, 2013
13,990
180
106
This is compared to their neighboring country such as Singapore, Malaysia, Thailand and Indonesia.

vietnam would likely be more powerful than malaysia or thailand. singapore is a developed country with strong commercial industry but it is a very small country.

indonesia is underdeveloped but a huge country with a large population and it is rising.

would say that vietnam is the most powerful of all of them but that indonesia will eventually become more powerful. all 5 of the countries have some amount of power
 

norseamd

Lifer
Dec 13, 2013
13,990
180
106
Well unless Malaysia can get their fact straight there is no point in wasting fuel and manpower on a wild goose chase. I read online that by the time vietnamese SAR planes get to the "crash site" they only have 20 minutes of fuel left to conduct the actual search! If Malaysia is really putting out false information or hiding stuff, all the countries should send them a big fat bill!

that and investigate any links malaysia has to terrorism or insurgents like the ones in southern thailand
 

Uppsala9496

Diamond Member
Nov 2, 2001
5,272
19
81
Payne Stewart situation? Cabin pressure issue; everyone passes out, pilots turned the plane around when they noticed a minor warning about it, however it turned out to be a major issue. Plane just kept coasting along on autopilot or was slightly nose down after the turn and cruised until it crashed?
 
Oct 25, 2006
11,036
11
91
Payne Stewart situation? Cabin pressure issue; everyone passes out, pilots turned the plane around when they noticed a minor warning about it, however it turned out to be a major issue. Plane just kept coasting along on autopilot or was slightly nose down after the turn and cruised until it crashed?

Issue has been tackled like 10 times.

Transponder shut off. That wouldn't have happened if cabin pressure dropped.
 

Brian Stirling

Diamond Member
Feb 7, 2010
3,964
2
0
Yes, I'm leaning towards a massive electrical power failure and loss of engines and that would explain the loss of communications. I guess there must be some separate power to operate the fly-by-wire controls otherwise the plane would not have been maneuverable and would not have been able to turn around. If this is what happened then it's likely they attempted an ocean landing and with the exception of Captain Sully there's not much chance of making a successful ocean landing. If they had made a decent landing then there would be people in lifeboats and that would have been seen by radar.

So, odds are the plane and its passengers are at the bottom of the ocean somewhere between the point it was lost on radar and Malaysia.

This is so strange it's going to be made into a movie...


Brian
 

norseamd

Lifer
Dec 13, 2013
13,990
180
106
Yes, I'm leaning towards a massive electrical power failure and loss of engines and that would explain the loss of communications. I guess there must be some separate power to operate the fly-by-wire controls otherwise the plane would not have been maneuverable and would not have been able to turn around. If this is what happened then it's likely they attempted an ocean landing and with the exception of Captain Sully there's not much chance of making a successful ocean landing. If they had made a decent landing then there would be people in lifeboats and that would have been seen by radar. So, odds are the plane and its passengers are at the bottom of the ocean somewhere between the point it was lost on radar and Malaysia. This is so strange it's going to be made into a movie... Brian

why not turn towards land and try to land near the coast or on land?
 
Oct 25, 2006
11,036
11
91
Yes, I'm leaning towards a massive electrical power failure and loss of engines and that would explain the loss of communications. I guess there must be some separate power to operate the fly-by-wire controls otherwise the plane would not have been maneuverable and would not have been able to turn around. If this is what happened then it's likely they attempted an ocean landing and with the exception of Captain Sully there's not much chance of making a successful ocean landing. If they had made a decent landing then there would be people in lifeboats and that would have been seen by radar.

So, odds are the plane and its passengers are at the bottom of the ocean somewhere between the point it was lost on radar and Malaysia.

This is so strange it's going to be made into a movie...


Brian

The reason this is very very unlikely from everything that's happening here is that every single backup generator powers the radio, the RAT automatically deploys on power loss and powers the hydraulics and radio. There is reduced handling but controls will still work and the radio still still work.

The only way to lose all radio and handling is if there is complete and total power loss from something cutting through the main conduits in the airplane. Save for some sort of flash fire or explosion, the chances of that happening without a mayday or anything are pretty slim.

The complete and total lack of any debris evidence is a huge issue among these "lose power" type moments.

I'm not quite sure how far an airplane can glide with NO control whatsoever. It won't immediatley crash, but it would drop alot faster than if it was actively piloted.

The "miracle on the hudson" incident only came off so well because the plane was a) never that high up in the first place, b) they crashed in the hudson, which isn't exactly rough seas and is easily within reach of resuce crew.
 

brainhulk

Diamond Member
Sep 14, 2007
9,376
454
126
I wonder if terrorists figured out how to make a pinch that can get through security
 
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