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Old 26th March 2014, 10:54   #286
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

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Originally Posted by audioholic View Post
The US airways flight was still at a low altitude when the engines failed. Yet it could glide for a few minutes. Hence I think that a flight in its cruising altitude Can glide for a longer period of time.
+1. The aerodynamic properties of a plane can keep it in air gliding for a long time, especially when it had reached cruising altitude. The aircraft will not fall from the sky abruptly.
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Old 26th March 2014, 11:17   #287
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

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@Jeroen, some interesting points there. Thanks for that.This is the only point I would like to add to. The wings are what hold the fuselage up in the air. The wings hold the engines which provide the power for the flight, and the wings also contain the flaps that help in ascent & descent. The fuselage is actually the load.
Technically speaking the fuselage is also part of the total aerodynamics of a plane. So whereas the wings create most of the lift, some of it could/is created by the fuselage as well.

The wings have large tanks, and most of the fuel is held in the tanks. Although, I'm pretty sure a 777 might have centre tanks as well (like a 747).

Especially towards the ends of a long flight the wing tanks will be just about empty, so greatly contributing towards buyancy. Not sure how the math would work out if they are still full with fuel. But even then, fuel is lighter then water, so you might still get buyancy, I just don't know exactly

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Old 26th March 2014, 11:25   #288
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

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+1. The aerodynamic properties of a plane can keep it in air gliding for a long time, especially when it had reached cruising altitude. The aircraft will not fall from the sky abruptly.
But then there is something called stall speed.
The airflow over the wings SHOULD be higher than this figure or else your wings will not generate sufficient lift and gravity will embrace you.

Flaps help decrease this figure (which means you can fly slower and still generate lift) - no wonder it is used during the takeoff and landing.
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Old 26th March 2014, 11:51   #289
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

If these are the search conditions, the delay or a possible loss of recovery is expected.

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Old 26th March 2014, 12:21   #290
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

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Here you will find what I think is the most comprehensive and factual write up to date:
Jeroen
Jeroen, What is the meaning of terms like FL350, FL295 etc?
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Old 26th March 2014, 12:32   #291
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

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If these are the search conditions, the delay or a possible loss of recovery is expected.
Probably one of the reasons no debris were found and just two or three pieces which are still not confirmed, were found in this area.

If the sea had been like this most of the times and the search in this part had started only recently, the parts of the plane would have spread out quite a bit and most of it sunk, before it could be seen.

Like putting some pieces of paper in a washing machine.
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Old 26th March 2014, 12:36   #292
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

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Jeroen, What is the meaning of terms like FL350, FL295 etc?

FL is abbreviation of Flight Level, which in layman terms mean altitude of the aircraft. It is normally conveyed in hundreds of feet. Hence FL350 means an altitude of 35,000 feet.
FL as I said is altitude in layman terms but altimeter in planes is only a calibrated barometer or a pressure altimeter, hence it is also specific barometric pressure. Hope I have not confused you. I manage to do it with even intelligent guys around

Edit: And sorry to bump up a question meant for Jeroen.

Last edited by saket77 : 26th March 2014 at 12:39.
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Old 26th March 2014, 16:34   #293
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

Conspiracy theory. If not already posted.

http://www.presstv.ir/detail/2014/03...-370-revealed/
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Old 26th March 2014, 21:45   #294
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

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Jeroen, What is the meaning of terms like FL350, FL295 etc?
See the answer below

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Originally Posted by saket77 View Post
FL is abbreviation of Flight Level, which in layman terms mean altitude of the aircraft. It is normally conveyed in hundreds of feet. Hence FL350 means an altitude of 35,000 feet.
FL as I said is altitude in layman terms but altimeter in planes is only a calibrated barometer or a pressure altimeter, hence it is also specific barometric pressure. Hope I have not confused you. I manage to do it with even intelligent guys around

Edit: And sorry to bump up a question meant for Jeroen.
No problem and your answer on what it means is spot on. How it is measured needs a little further explanation, because Flight Levels are given against a set barometric pressure of 1013.25 hPa (29.92 inHg), and therefore is not necessarily the same as the aircraft's true altitude.

Let me explain in what I hope are simple terms. For obvious reasons it is necessary to get an accurate way determining altitude for each and every plane in the sky. The first thing you need to do then is to agree a datum, i.e. what do you call 0 (zero). In aviation (and in other fields as well) altitude is measured against Mean Sea Level (MSL). Altitude above MSL can be easily measured as indicated before by measuring the air pressure. Essentially the further you are away from zero the lower your reading will be. However, you do need to adjust for the actual local barometric pressure. Again, I'm simplifying here. When you're flying at relative low altitudes you need to constantly adjust your altimeter for actual barometric pressure. These values are transmitted constantly as part of the ATIS messages on the radio, or Air Traffic Control will be able to tell you. It is very important to do this often and set your altimeter accurately. Before you know it you can introduce and error of hundreds of feet.

If you want more details/ information have a look here:

https://www.faa.gov/regulations_poli...apter%2007.pdf

On long hauls, and high up, the constant adjustment of the altimeters is not practical so once you climb above a certain altitude you will switch to what is known as pressure altitude or sometimes also referred to as standard altitude. What you do is you dial in a set (standard) pressure. The altitude where you change over is known as transition altitude. From there upwards you call out the altitudes as Flight Levels

Above the transition altitude everybody sets their altimeter to 1013.25 hPa (29.92 inHg). This will ensure vertical separation. Below the transition altitude, as explained you need to constantly adjust your altimeter for actual barometric pressure. This will do two things. It will ensure vertical separation between planes, and it will tell everybody their altitude above ground. Aviation charts typically show altitudes as above mean seal level. So for instance Delhi airport is at 773 ft above sea level. So with the plane on the ground and the correct barometric pressure set the pilots altimeter will read 773 ft.

The transition altitude is different around the world. In the USA it's (mostly I think) 18000 feet, where as in Europe it varies from a couple of thousand feet upwards.

Have a look for some more detail: http://en.wikipedia.org/wiki/Flight_level

So, a flight level will ensure vertical separation it does not indicate how high up you are from the ground or from MSL. But at Flight Level altitudes that is of no relevance.

You will notice we are talking about feet, there are a few countries out there that are using metric measurements. So they will have altitudes expressed in meters and Flight Level in hundreds of meters. Altimeters of most commercial airliners have an option to simply switch the scale of the altimeter from feet to meter and vice versa.

Hope this help,

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Old 26th March 2014, 23:03   #295
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

Thanks a lot Condor and Jeroen. This really helps.
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Old 27th March 2014, 09:05   #296
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

New angle. Doesnt look nice. Hope it's not true.

http://www.dailymail.co.uk/news/arti...ys-friend.html
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Old 27th March 2014, 09:51   #297
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

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Originally Posted by condor View Post
New angle. Doesnt look nice. Hope it's not true.

http://www.dailymail.co.uk/news/arti...ys-friend.html
Can't say it is true or not at this moment. But could not negate this possibility. Remember Karl Slym, MD Tata Motors suicide case in Thailand. Family feud can lead stress to any direction.
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Old 27th March 2014, 10:05   #298
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

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Can't say it is true or not at this moment. But could not negate this possibility. Remember Karl Slym, MD Tata Motors suicide case in Thailand. Family feud can lead stress to any direction.
Let's see if the story holds. It is certainly not unknown for people under great duress to undertake extremely "out of character' actions.

Partners leaving, divorcing is one of the most stressfull events for most people. Some airlines have policies aroudn this, so if yuo find yourself in a stressfull family situation, you can discuss and you could be taken of the active duty roster, wich no impact on pay.

Certain airlines even do this for when wife's are getting close to giving birth. Husband wants to be there and might take more risk in getting home then normal. Although you won't find it in the accident report, the world largest aviation accident, the infamous KLM-PANAM Tenerife disaster had such an element in it. The KLM captain has personal reason to go home quickly and that, most likely, influenced his decision to commence and continue the take off and subsequently crash into the Panam Jumbo.

Even today, statistically speaking, more accidents happen on the inbound leg compared to the outbound leg. So when flying home, pilots (all pilots from GA to commercial) are likely to take bigger risks. Good pilot training will adress and put a lot of emphasis on these factors, how to recognize and deal with them.

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Old 27th March 2014, 10:07   #299
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

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New angle. Doesnt look nice. Hope it's not true.

http://www.dailymail.co.uk/news/arti...ys-friend.html
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Originally Posted by anujmishra View Post
Can't say it is true or not at this moment. But could not negate this possibility. Remember Karl Slym, MD Tata Motors suicide case in Thailand. Family feud can lead stress to any direction.
If that is true, then it is the toughest 'weak link' to deal with for the aviation safety experts. One can plug in technical weak holes and operational issues but the toughest & most tricky part is to deal with human psychology, not only in aviation, but on any front.
Feel sorry for the pax and even for the airlines (for the mess they have been into) if that news is really true.
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Old 27th March 2014, 11:01   #300
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Re: Malaysian Airlines Boeing 777 (MH370) goes missing

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If that is true, then it is the toughest 'weak link' to deal with for the aviation safety experts. One can plug in technical weak holes and operational issues but the toughest & most tricky part is to deal with human psychology, not only in aviation, but on any front.
Although all pilots have to undergo very strict medical test on a regular basis every pilot needs to "declare" him/herself fit for duty, mentally and physically, for every flight.

There is nobody else that does that for you, you just have to be very frank and honest with yourself. Proper training does help and certainly the various FAA programs have shown that pilots that take this seriously are statistically speaking safer pilots (less likely to have an accident).

Airlines need to promote this too. Needs to be embedded in the companies flight safety philosophy and in the actual policies supporting the implementation.

So I'm very cautious of airlines that pay their cockpit crew by the hour flown, rather then a fixed base salary. Because if you know you won't get paid unless you fly, what will that do to your "honest and frank" self assessment before each flight?

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