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Link from post above. Very informative.

A description of alternate law as it applies to aviation can be found here although this focuses on Airbus.

The air handling pack on a modern airliner takes hot high pressure bleed air from the engines and mixes it with cold low pressure ambient air to create the desired temperature in the cabin. This is why you can sometimes smell fuel come through with the air.

More info:

http://skybrary.aero/index.php/Bleed_Air_Systems

The pilot of an aircraft has many legal, emergency, and crew leadership duties which go beyond the actual piloting of the aircraft.

Being a pilot has been described as long periods of boredom punctuated by seconds of sheer terror.

The pilot shortage is a red herring, like any other occupation, if you pay people commensurate to their educational investment, skills, knowledge, experience, and continue their training. The airlines have had a pretty good ride up until now because they piggy-backed on the military as a pipeline.

I'll post my reply here, but there are a few other sibling posters asking similar questions.

This report collates historical data on in-flight fires. From the report: "Fire in the air is one of the most hazardous situations that a flight crew can be faced with. Without aggressive intervention by the flight crew, a fire on board an aircraft can lead to the catastrophic loss of that aircraft within a very short space of time. Once a fire has become established, it is unlikely that the crew will be able to extinguish it. The following table from a UK CAA report in 2002 supports the generally held view that, from the first indication that there is a fire onboard the aircraft, the crew has on average approximately 17 minutes to get the aircraft on the ground."

Crew guidance

It's not all doom and gloom, here is a more moderate report from the FAA.

I'll agree entirely with the observations that most cabin materials are fire retardant, and this is a very good thing. However, we are considering a very dense energy source that can spontaneously combust. In addition, have you noticed that airlines won't let you fly with a spare laptop battery in your checked luggage? They are very concerned about a spontaneous fire in the luggage hold, where most of the material is certainly not fire proof.

Safe travels everyone.

I'll post my reply here, but there are a few other sibling posters asking similar questions.

This report collates historical data on in-flight fires. From the report: "Fire in the air is one of the most hazardous situations that a flight crew can be faced with. Without aggressive intervention by the flight crew, a fire on board an aircraft can lead to the catastrophic loss of that aircraft within a very short space of time. Once a fire has become established, it is unlikely that the crew will be able to extinguish it. The following table from a UK CAA report in 2002 supports the generally held view that, from the first indication that there is a fire onboard the aircraft, the crew has on average approximately 17 minutes to get the aircraft on the ground."

Crew guidance

It's not all doom and gloom, here is a more moderate report from the FAA.

I'll agree entirely with the observations that most cabin materials are fire retardant, and this is a very good thing. However, we are considering a very dense energy source that can spontaneously combust. In addition, have you noticed that airlines won't let you fly with a spare laptop battery in your checked luggage? They are very concerned about a spontaneous fire in the luggage hold, where most of the material is certainly not fire proof.

Safe travels everyone.

From the onset of a cabin fire you have 17 minutes to get the plane on the ground before complete loss of the aircraft.

The growing situation with batteries is bloody terrifying. Will it take a total loss of aircraft before a better solution (than just an outright ban) can be found? Could this be what happened to MH-370 last year?

He he, offtopic absolutely.

Apple shill, not one bit. Their products are absolutely over-priced and under-featured.

The problem here is that why would you even choose to line up over issues as banal as smart phone choice? Young men have lined up and shot at each other over the fancies of the rich and powerful and I've always regarded that as tragic. But the older I get the more I realise that those instincts are more intrinsic than I realised.

It's a real shame that Samsung have wasted all that effort producing a product that does not work. It was not the first and it won't be the last company to do so. What is terrifying is that aircrew have 17 minutes to get an aircraft on the ground following a cabin fire, otherwise the result is total loss of the aircraft. Think about that for a minute and then decide whether you wish to fly anywhere, let alone over the Atlantic, while these products are in circulation.

Got yer app right here...

they're designed to not fail catastrophically

Correct.

What they're not generally designed to do is survive in an operational manner.

Wrong.
See here for the requirements. This article (quoted below, emphasis added) puts the former article into easier-to-understand English.

Current standards, for both multiple and single bird engine ingestions into a single fixed wing aircraft engine, exist in equivalent form in 14 CFR Part 33-77 and in EASA Airworthiness Code CS-E 800 ’Bird Strike and Ingestion’. The basic requirements for engine ingestion were revised in 2000 to take account of both evidence of an increase in the size of birds impacting aircraft and issues raised by the development of very large inlet, high by pass ratio, engines. The requirements, to be demonstrated by testing, are, in outline, now as follows:

* That at a typical initial climb speed and take off thrust, ingestion of a single bird of maximum weight between 1.8kg and 3.65kg dependent upon engine inlet area shall not cause an engine to catch fire, suffer uncontained failure or become impossible to shut down and shall enable at least 50% thrust to be obtained for at least 14 minutes after ingestion. These requirements to be met with no thrust lever movement on an affected engine until at least 15 seconds have elapsed post impact.

* That at a typical initial climb speed and take off thrust, ingestion of a single bird of maximum weight 1.35kg shall not cause a sustained thrust or power loss of more than 25%, shall not require engine shut down within 5 minutes and shall not result in hazardous engine condition.

* That at a typical initial climb speed and take off thrust, simultaneous ingestion of up to 7 medium sized birds of various sizes between weight 0.35kg and weight 1.15kg, with the number and size depending upon the engine inlet area, shall not cause the engine to suddenly and completely fail and it shall continue to deliver usable but slowly decreasing minimum thrust over a period of 20 minutes after ingestion. [Engines with inlet sizes of less than 0.2 m2 (300 square inches) only have to meet the standard for a single bird of this weight]

* That at a typical initial climb speed and take off thrust, simultaneous ingestion of up to 16 small sized birds of weight 0.85kg, with the number dependent upon the engine inlet area, shall not cause the engine to suddenly and completely fail and it shall continue to deliver usable but slowly decreasing minimum thrust over a period of 20 minutes after ingestion. [Direct testing to this standard may not be required if the medium bird multiple standard is demonstrated or if this bird size can pass the inlet guide vanes into the rotor blades]

"then one of the brave pilots managed to dial in a rough turn to home into the autopilot before either fleeing the cockpit or dying"

The plane turned and tracked perfectly to the longest runway in the area - Pulau Langkawi

Pulau Langkawi is on the east side of Malaysia, a LOT longer than KL and has an easy ocean approach. KL is on the opposite side of Malaysia to the flight and there are 8000 foot mountain ranges in the way.

After passing Pulau Langkawi it seems to have been blown around by high altitude winds and got itself into (and stalled out of) coffin corner.(*)

Much of the "skirted around islands" shit was down to various countries refusing to admit that it went straight overhead without setting off their alert systems and the remaining tracks fit the known wind directions that day.

This insistence comes down to "Loss of Face" - Indonesia eventually admitted they had no records for the aircraft - not that they'd tracked it flying around their territory - and that admission involved greater loss of face than their initial denials.

All in all the most likely explanation is some sort of catastrophic failure which overwhelmed the crew between the time they turned around and the time the plane reached the field (easily explained by a fire fed by the cockpit oxygen system(**)). The pilot was known to be fastidious about planning and to have kept alternates programmed into the autopilot for each leg of his flights.

"What this all screams to me is that planes should be sending a regular report up to the satellites."

Many do. It's an added cost option on 777s and Malaysia airlines declined to spend the money for it. Such squawks are how the Air France debris was initially located.

MIA was facing major cutbacks after massive losses. Airline staff in all areas were reported to be lacking morale and there had been a large number of safety incidents both in the air and in maintenance shops (including a major cigarette-started fire which destroyed a lot of stuff in a heavy maintenance hanger, in an area which is non-smoking). The odds are high that this was another such event.

http://www.wired.com/2014/03/m... - remains the most compelling theory.

The only conspiracies which need to be considered are those of coverups - both within MIA and within various neighbouring countries military as they don't want to admit how badly they dropped the ball.

Having seen airlines go out of their way to deny culpability (Air New Zealand TE901), I'm quite prepared to believe that manglement would throw the pilots under a bus to save their own wretched skin.

(*) The electrical fire theory (possibly oxygen fed(**)) could have dumped all sorts of random garbage into the autopilot, but the general feeling is that after Pulau Langkawi the plane was simply flying "straight and level" (which will inevitably result in altitude changes unless manually corrected) and no bearings set, so crosswinds would cause directional changes - and all the known changes match prevailing winds at altitude.

(**) http://www.iasa-intl.com/folde... http://www.skybrary.aero/index...

The point of having pilots in modern airliners is precisely to intervene when automation fails. This happens. There are procedures for it.

The majority of the dose at airline altitudes is from neutrons (55%), with only a small component from photons (gammas are photons) - 5%. This is, of course, on average. I do not think anywhere in the preprint they claim to be able to measure anything but photons. Therefore, a cell phone will not do a great job of monitoring your radiation dose at airline altitudes.

However, there is a tool being developed by NASA which does a real-time calculation of your radiation dose along an airline trajectory. Check out NAIRAS

References:
Cosmic Radiation @ skybrary
NAIRAS aircraft radiation model development, dose climatology, and initial validation

From flight training a long time ago, engine failures tend to happen on takeoff. At that moment a two-engine plane that suddenly loses one engine is probably in more trouble than a single-engine plane with no engine working. The single has a reasonable chance of gliding somewhere and making a dead-stick landing. Unless the pilot does exactly the right things, very quickly (two-three seconds), the plane is likely to flip sidewise and drop out of the sky, with not enough altitude to correct the situation. I already cited this article once, here 'tis again. And the numbers are there, probably on the net somewhere (I haven't looked at this stuff for a couple of decades) - NTSB flight accident stats tend to be very explicit.

It's been a couple of decades since I took flying lessons, but here goes: Engines tend to die at the worst possible moments, when they are under the most stress. This is during the takeoff phase, when you are still relatively close to the ground. In a twin-engine plane, when one of the engines dies, it has two effects - one is that the plane suddenly has both a terrific off-center thrust and an increase of drag from the stopped propeller, causing yaw (rotation on the vertical axis), and the other is that the loss of the balancing effect of counter-rotating engines and the yaw-induced loss of lift on the slower wing drastically increases the tendency to roll (rotation on the line-of-flight axis). All in all, the loss of performance is much more than just the loss of thrust.

So when one engine dies, the pilot has a couple of seconds to do the right thing, or else the plane suddenly flips and dives sidewise (like those videos of fighter planes peeling off for a run at the enemy ship) the 300-1000 feet to the ground - too enough altitude to recover. The 'right thing' is pretty complicated according to this. Some of it is counter-intuitive (so should be practiced during training). If you're fast, and lucky, you'll be able to go around and land.

Good grief, you're serious, aren't you? Answer: About negative a million times.

Ummm...pot meet kettle.

I was actually more referring to cat III autoland rather than straight an level autopilots. Autoland is used when conditions are less than optimal and typically do better than the pilots can do under optimal conditions.

and even then, that's by massive cheating using lidars and GPS

That's not cheating. Those are the very technologies that are going make it practical. Or rather improved and cheaper computing making those technologies affordable is what is making it practical.

Projects involving a BDFL tend to suffer, in reputation if not in functional potential, when s\he says or does something stupid. Among operating systems, this applies to Linux as well as OpenBSD, Minix, and others - but not to FreeBSD.

And this was indeed a very stupid thing to rant about. Romney was obviously joking. (Coincidentally, designing an aircraft fire extinguishing system that uses a rapid burst of cold air from the outside to "blow out" the flame, while probably not the most practical approach, is not outside the realm of possibility.) The only reason why anyone would lash out at Romney in this way is due to prior political convictions against him.

Celebrity programmers are obviously entitled to their opinions, but putting so much emotion into a political preference, even on a personal blog, inevitably influences the culture of their projects. The peer pressure among naive young people to support "liberal" (in USA'ian usage, s/liberal/socialist/) causes continues to grow. People who like Romney (or at least see him as a lesser evil among the viable candidates, as I do) will no longer feel welcome in the Linux world.

The choice of a restrictive anti-business "copyleft" license was of course a much bigger reason for non-socialists to avoid Linux, but now we have one more.

--libman

I said "pilot" because, at any given time, there is only one pilot touching the controls.