khaosai

...getting OT. Skippy made the statement that the aircraft would after losing both engines simply maintain its last established IAS, which implies whatever pitch angle and rate of descent it takes to maintain that IAS. And he stated immediately prior that all airliners are dynamically stable in all 3 axes. Does "stability" imply this ability to take up & then maintain a constant-speed descent with no power on the aircraft, and thus nothing driving (and further, no movement of) the elevators?

So let's say MH370 is cruising at .84M equals about what, 480KIAS? According to skippy, when the engines fail and autopilot goes away, MH 370 takes up a descent at 480KIAS and flies it all the way down. I'm not sure what vertical speed that represents, but I'm pretty sure the plane would be smacking the wavetops pretty hard...

Hi,

The indicated speed would be much less than 480 knots. More like 270 knots indicated. 480 knots would be close to the true airspeed however.

...getting OT. Skippy made the statement that the aircraft would after losing both engines simply maintain its last established IAS, which implies whatever pitch angle and rate of descent it takes to maintain that IAS. And he stated immediately prior that all airliners are dynamically stable in all 3 axes. Does "stability" imply this ability to take up & then maintain a constant-speed descent with no power on the aircraft, and thus nothing driving (and further, no movement of) the elevators?

Hi,

so many variables, and as stated earlier it's unlikely both engines stopped at exactly the same time. All this also assumes the aircraft did not achieve a controlled ditching under power.

I would imagine with both engines failed, no autopilot, and no one flying the aircraft then the following may occur:

Pitch down, height loss, acceleration, pitch up, speed loss, pitch down and so on until stall resulting in a large impact with the ocean.

A much less likely scenario similar to the above, but resulting in a much smoother belly contact, wings level. Highly unlikely.

Commercial jets are aerodynamically stable in all axis

If all went off, it would basically descend at the last IAS which would usually have some nose down

Contrary to popular belief:-

Power is for up and down

Elevators are for speed

Sent from my iPhone using Thaivisa Connect Thailand mobile app

My Chipmunk elevators pushed my nose up or down. But I'm curious how they're used for speed. Do you flap them like a mermaid's tail? Please explain how "elevators are for speed".

Hi,

I think it's fair and simplistic to say you can use both pitch and thrust to control speed during normal operations.

If for instance the aircrafts required indicated airspeed reduces close to the ground I certainly would not pitch forward to return the speed to where it should be, increasing thrust would be far more appropriate.

Different training organisations teach different methods with regards to pitch and power to maintain profile. Keep it simple, use nice smooth inputs to both to achieve the desired result.

So plane runs out of fuel, autopilot makes corrections to maintain level flight?

Does autopilot in such circumstances say to itself, I need to land this plane?

Whether the pilot was alive or dead, or whether the plane impacted relatively intact, or severely damaged remains unanswered.

Correct?

Aircraft runs out of fuel equals autopilot disconnect.

Autopilot no longer talks to the aircraft.

So it would have crashed with considerable damage?

It would have crashed/ditched. What sort of damage it would have suffered is very subjective. That will be confirmed when they recover the flight data recorders.

So plane runs out of fuel, autopilot makes corrections to maintain level flight?

Does autopilot in such circumstances say to itself, I need to land this plane?

Whether the pilot was alive or dead, or whether the plane impacted relatively intact, or severely damaged remains unanswered.

Correct?

Aircraft runs out of fuel equals autopilot disconnect.

Autopilot no longer talks to the aircraft.

If both engines fail on the B777 then the autopilot will automatically disconnect until such time that you get a generator working when you can then re engage the autopilot. That's not going to happen with fuel exhaustion of course.

But the likelihood of both engines suffering fuel exhaustion simultaneously is probably zero. If one failed, the auto pilot would run out of authority, and the aircraft would begin to roll, the AP would then disengage, and the aircraft would crash.

Hi,

That's true for a conventional aircraft but not necessarily so on the B777. The aircraft has thrust asymmetry compensation which works when an asymmetric situation is detected with a change in engine thrust of 10% or greater. Rudder is then automatically added to reduce yaw and will try to fully compensate for a failed engine once airborne.

It will should continue to work with just a flame out, but in situations of severe damage it generally disconnects.

I'm not saying you're wrong, but that would be a real accomplishment. In layman's terms, if the right engine quits, the left engine will push the plane into a turn to the right. The plane will begin to bank to the right as the fuselage blocks some of the airflow from the right wing but not the left wing. The reason the airflow will be blocked is because it isn't a coordinated turn.

If a pilot is in control, he will force the plane to .bank to the left using rudder and aerolons at the back of the wings. He will continue to hold this until he has the plane flying straight and steady, but not evenly. In essence he's banking and turning left just enough to counter the right turning push from the good left engine.

Will an autopilot do that, and keep doing that?

Yes it will.

If both engines fail on the B777 then the autopilot will automatically disconnect until such time that you get a generator working when you can then re engage the autopilot. That's not going to happen with fuel exhaustion of course.

But the likelihood of both engines suffering fuel exhaustion simultaneously is probably zero. If one failed, the auto pilot would run out of authority, and the aircraft would begin to roll, the AP would then disengage, and the aircraft would crash.

Hi,

That's true for a conventional aircraft but not necessarily so on the B777. The aircraft has thrust asymmetry compensation which works when an asymmetric situation is detected with a change in engine thrust of 10% or greater. Rudder is then automatically added to reduce yaw and will try to fully compensate for a failed engine once airborne.

It will should continue to work with just a flame out, but in situations of severe damage it generally disconnects.

It think it's possible it was ditched with only one crew member being alive, but I still have difficulty with him flying it for 6+ hours before then committing suicide. It's possible he also died in a depressurization, but then the chances of the auto pilot flying it on after fuel exhaustion, without any breakup, and therefore significant debris, is about zero.

Hi,

Your correct, zero chance of that happening.

If both engines fail on the B777 then the autopilot will automatically disconnect until such time that you get a generator working when you can then re engage the autopilot. That's not going to happen with fuel exhaustion of course.

Hi,

Here is a pic of an aircraft onboard navigation display with the wind speed and direction and the effect it has on the aircraft progress.

The wind speed is 210 knots which equates approx to 240 MPH or 390 KM/H.

The information on the ticket will be the scheduled block time I would imagine and if flight time is mentioned will be an approximation as it's such a variable.

Only a certain part of the Ukraine airspace is closed at the moment, however an airline may choose to avoid it completely.

Hi,

The root cause goes right back to the check in procedure. The bags have obviously been taken off the passengers prior to boarding as deemed to large or heavy for the over head storage onboard.

Still no excuse for dropping the bags from that height tho, but give the staff the proper tools to deal with these issues if they arise.

<snip>

As much as I hate cigarettes, not sure how smoking pilots in the cockpit smell can get to the passenger cabin.

I can think of at least one regularly occurring example of how smoke can get out a 'sealed' cockpit (assuming it does happen to be sealed)

If either pilot comes out to use the toilet, or the cabin crew take in a coffee/snack/whatever, then you're going to smell it if you're anywhere in the front half of the aircraft. A 737 ain't a big space.

Hi,

Quite often on aircraft the flight deck will get a 100% fresh air supply from one of the air conditioning packs. The air in the flight deck is provided at a slightly higher pressure than the passenger cabin to prevent any unwanted smoke or odors entering. This could cause the passengers in the cabin to be aware of a pilot smoking I guess.

The passenger cabin will get its air supply from another air conditioning pack. The cabin air will be part recycled with most of the unwanted odors vented overboard.

Each airline will have a policy regarding smoking onboard. I don't know the Nok Air policy. It may stipulate no smoking onboard. It may say passengers must not smoke onboard. It may well be a very senior management pilot abusing his position. So many variables, frustrating to some I guess. Vote with your feet and choose another carrier.

I forgot to mention another 'job' that transponders have.

They are part of the TCAS (Traffic Collision and Avoidance System), and are interrogated by other aircraft, e.g., if two aircraft are approaching head on (but it can be from any angle, any calculated conflict) at the same altitude, the transponders interrogate each other, the circuitry determines what course of action is best, and a voice command is received in each aircraft, but it can never conflict. One aircraft will be told to turn left, and the other to turn right, or one to climb, and the other to descend.

Interestingly, when TCAS was first introduced, a protocol hadn't been established, and controllers gave conflicting instructions to the aircraft. Pilots, conditioned to accepting ATC instructions, followed those, and couple of head ons resulted. Nowadays, controllers are ignored and ONLY TCAS commands are acted upon. TCAS is that accurate and reliable.

Wikipedia makes some sense http://en.wikipedia.org/wiki/Traffic_collision_avoidance_system

Hi,

The transponders on the latest generation of commercial aircraft does not need to be switched off to change code. The last time I did that was on a light aircraft which was a long time ago.

The latest version of TCAS is excellent, but it does not give left and right commands, only vertical commands.

It's remarkable that they have not found any debris, but hopefully they will locate the recorders soon.

wprime,

You're talking in riddles, and the fact that you said that for a fire outside the aircraft you climb to an altitude as high as is safe, and your incorrect use of aviation terminology, shows you have NO knowledge of aviation. A fire cannot be sustained outside the aircraft at altitude. An aircraft levels out at an altitude, not 'steadies'.

The aircraft would only climb on a fixed thrust if the auto throttle was disengaged (you're confusing autopilot and auto throttle), and would only stop climbing if the altitude was set in the FMC way above what it could realistically achieve at the weight, at which time it would descend and climb in an oscillatory pattern. That would also depend on the climb mode selected. Pilots don't like disengaging the autothrottle, and many airlines mandate that it not be disengaged, except for training/demonstration purposes, and that's more likely to be done in a simulator. Disengaging the SPD mode is far safer, and still gives minimum speed protection. The B777 that crashed at SFO had the ATP disengaged. If had only had SPD mode disengaged, it wouldn't have crashed.

I recently retired with 20,000+ hours aviation experience, most of it on high performance jets, and I choose not to engage further with somebody who has no idea, but please don't post such rubbish because you do no more than make a fool of yourself.

I don't disagree with anything you said, but for laymen may we clarify a bit? Yes engines lose some power at altitude due to lack of oxygen, but they more than make up for it due to lack of wind resistance on the airframe in the thinner air. Cruising altitude is where they get their best fuel economy.

Yes, of course planes level off after climb or descent, but they begin a round off well before they get there for, if no other reason, to keep the passengers from feeling the change.

Planes burn a lot of fuel during climb out, but more than make it up by cruising in the thin air. Then they get the bonus of the descent when they glide back down with little to no power, but still maintaining speed due to the descent.

Take a lightly loaded Lear jet. It can climb out at 4,000 feet per minute and reach 40,000 feet in 10 minutes. There's a lot of fuel. But if it cruises for an hour, traveling about 600 miles, it will make it up. Then the bonus is that it must begin a descent from about 200 miles out, which is almost free as the descent keeps the speed up without much power.

If the plane starts down at 200 miles out traveling 10 miles per minute and descends at 2,000 feet per minute, it will take it 20 minutes to descend. That's 200 miles of nearly free flight.

The one thing I'm not sure about is that in a Lear, we blasted all the way to the beginning of the round over at nearly full throttle. I don't know what a 777 does.

Cheers

Quite right, engines do lose power due to rare air, but pick up TAS (true air speed), but that's not at the usual cruising altitude, typically, mid 30,000's, to 43,000. The best TAS for fuel burn for most engine/airframe combinations is around 28-30,000'. Thereafter, fuel burn increases, and TAS decreases, but the benefits are generally a smoother ride, and greater groundspeed due to higher upper level winds if flying east. Flying west is generally at lower altitudes.

High fuel burn on climb is just part of the game, it's unavoidable if you want to get to altitude as you must.

Descent is almost free as you say, and if you spend 30 minutes climbing, and 20 minutes descending, it does reduce the . If you were burning 20-25 tonnes an hour on climb, that would be 12-12.5 tonnes on climb, and then on descent, it would only be about 2 tonnes per hour, so about 700 Kg (.7 tonne) burnt, a total for 50 minutes of about 13 tonnes (15.6/hr), still more than cruise of 10 tonnes per hour by 50+%, but much better than cruising lower. The fuel burn at low altitude in a jet makes the company accountant's eyes water.

Tallking Lears, I recall reading about Bill Lear's personal aircraft many years ago, and it could climb at 12,000 fpm!! Many years ago I flew a 737/500 with 24,000 lb thrust engines, and one of the airports we operated out of required a 270 degree turn from 500'. We could set heading over the top of the field coming out of the turn at 12000, fully load of pax, but not max weight, a climb rate of 8000 fpm!!

Back to the search. The hard work is just beginning and even with a search area of 40,000 sq kms, (200 X 200 kms) it could take a long time, if in fact they have reliably narrowed it down to that zone. It would seem that the oil slick may be a good lead though if it's proven to be from MH370, and is still leaking. If it's just drifiting, it could be worthless.

The headline on the aircraft being flown like a fighter seemed a bit sensationalist, and typical of the press. Flying low isn't flying like a fighter because they typically operate at altitude, and it still wouldn't avoid radar if manoeuvering in tight turns etc.

Hi,

All good stuff.

Best TAS on the B777 is at approx 30000ft. Fuel burn on climb will be in the region of 5 to 6 tons depending on model and weight and takes from 15 mins to 30 mins, again depending on weight and model.

Fuel used on descent is such a variable, but generally in the region of 700kg to 1000kg.

wprime,

You're talking in riddles, and the fact that you said that for a fire outside the aircraft you climb to an altitude as high as is safe, and your incorrect use of aviation terminology, shows you have NO knowledge of aviation. A fire cannot be sustained outside the aircraft at altitude. An aircraft levels out at an altitude, not 'steadies'.

The aircraft would only climb on a fixed thrust if the auto throttle was disengaged (you're confusing autopilot and auto throttle), and would only stop climbing if the altitude was set in the FMC way above what it could realistically achieve at the weight, at which time it would descend and climb in an oscillatory pattern. That would also depend on the climb mode selected. Pilots don't like disengaging the autothrottle, and many airlines mandate that it not be disengaged, except for training/demonstration purposes, and that's more likely to be done in a simulator. Disengaging the SPD mode is far safer, and still gives minimum speed protection. The B777 that crashed at SFO had the ATP disengaged. If had only had SPD mode disengaged, it wouldn't have crashed.

I recently retired with 20,000+ hours aviation experience, most of it on high performance jets, and I choose not to engage further with somebody who has no idea, but please don't post such rubbish because you do no more than make a fool of yourself.

Hi,

All good points F4UCorsair however the B777 auto throttle is far safer with speed (SPD) mode engaged. The threat comes from hold (HLD) mode. No auto throttle wake up if in hold mode.

Hi hawker9000,

You mentioned that if the pilot had attempted a controlled ditching he would not have succeeded. You may well be right, but truth be told you and I don't really know.

It may well be possible with the correct techniques applied along with copious amounts of luck. It may well be impossible regardless of technique or an abundance of luck.

I do however enjoy the various theories people on here come up with. Nothing wrong with some healthy debate and opinion regardless of whether an expert or not.

Oh, you're right, I don't "know", I wasn't there, I didn't see it, and I've never ditched an airplane myself. But I know a little... And I've tried to share what I know as clearly and objectively as I can, without just saying "no, it couldn't have" without explanation, and not really seen any thing to the contrary posted except either "well it just could" (unsupported) or examples of smaller transports doing it in calm water (which I've also specifically addressed). And I just don't think it actually IS possible under all the circumstances of this case. Else I wouldn't have said it, and I've detailed, repeatedly and at length, my reasons for saying so. I wasn't just spit-balling something. Go ahead and give us your facts (but please, please, please, let's not just keep repeating the same unsupported theories & claims I've already repeatedly addressed).

This bizarre insistence on continued debate of this particular issue puzzles me - does anyone really think there's some scenario that has the pilot flying all that time and all that way just to finally try and save the aircraft in a controlled ditch? (I've asked this before, but none of those insisting on this whole ditching thing seem to want to respond...) Why would he do that? I could understand emergency circumstances maybe forcing him to attempt it (regardless of his chances) much earlier in the flight but not way out there in the middle of a famously rough ocean after (one can only suppose) deliberately exhausting his fuel and losing himself to anyone who might want to find him. What's the reason for all this palaver? We're just beating to death the esoteric difference between could have and would have. What's the point? But at this point, if it's all that important to you to think that he could have successfully ditched out there, that's fine. Be my guest and have the last word and then, really now, let's move on to stuff that's more relevant.

Hi,

It's surely all relevant until the FDR sheds light on the actual facts of what went on during the flight. I can't imagine the authorities have discounted the issue of an attempted successful ditching and potential motives of why. Crew or passenger motivation will continue to be looked at closely, in addition to the multiple failure scenario. As a current experienced B777 training captain I certainly have an interest in what's happened. That also includes did the aircraft successfully ditch.

Like all topics, it's a choice we all have on whether to participate in things you are interested in or not.

Repetition is inevitable with people joining the topic part way through. It's really not that big a deal.

So what's the answer for lack of debris do you reckon?

This is all kind of academic, as I doubt very much the pilot flew all those extra hours and miles out into the middle of a particularly rough area of ocean just to end up conducting a precision ditching drill. Much more likely I think that the aircraft, if it did indeed come down there, came down without power, on its own without pilot control, in a high rate of descent, and with no regard or planning for wind direction or sea state.

Thanks for the details. Since there are so many oddities about the plane's disappearance, I'll add another possible scenario: pilot was still alive near end of odyssey, and timed ditching for right before fuel ran out - in order to power an abrupt nose-up turn upwards, just above sea level. Granted, he would have known about rough seas, and the dynamics of a fuselage of a large plane breaking upon impact on water. Yet, it fits with the supposed scenario of him wanting his crime to be as un-findable as possible - along with the odd route the plane purportedly took - to a remote region.

Huh? So, suicide? Or not? If yes, then why an absurd attempt at an impossible ditching. If not, and he had some expectation of personal survival, why not turn back toward land at some point, rather than choose the roughest, most remote seas accessible to him instead? And if he wanted "unfindable", and wasn't expecting to survive, then why not a steep or vertical dive, a la Silk Air, which would grind up the aircraft about as finely,and leave as little to be found, as possible?

OK - I'm saying that if he DID attempt a controlled ditching, whatever the convoluted reasoning behind it, he wouldn't have succeeded. Period. He might as well have attempted to hide the evidence of his crime by trying to fly it into outer space.

The whole intended ditching concept in those search areas is just too far-fetched. But you seem pretty locked in to this idea of a ditched aircraft waiting to be found. Well, maybe some giant methane bubble burst to the surface like a monster airbag precisely at the right location and just before the 777 crashed down, or maybe an alien tractor-beam caught MH370 and set it down gently on the water. Whatever.

Meanwhile, back in the real world, they make those black boxes to survive the most catastrophic mishaps, so I think it's reaonable to hope they won't have been destroyed. Whether they can be found & retrieved off the bottom, however deep & uneven it actually is there, is another question I couldn't even guess at. 'Sure hope so though.

Hi hawker9000,

You mentioned that if the pilot had attempted a controlled ditching he would not have succeeded. You may well be right, but truth be told you and I don't really know.

It may well be possible with the correct techniques applied along with copious amounts of luck. It may well be impossible regardless of technique or an abundance of luck.

I do however enjoy the various theories people on here come up with. Nothing wrong with some healthy debate and opinion regardless of whether an expert or not.

Hi,

Still no definitive information on whether the aircraft flew back across the Malaysian peninsula then North West bound or immediately turned South from the Vietnamese boundary.

A North West route then turning Southbound would be more likely deliberate action. The other scenario which would take it directly over Indonesia could possibly be multiple uncontrollable failures leading to loss of control.

If the aircraft had hit the ocean at high speed I would still expect debris to be visible somewhere by someone.

The best description of flight path I have seen is this one.

http://www.bbc.com/news/world-asia-26503141

It's a good summary, yes but has many assumptions to 'fill in the gaps'. The truth is that we really DO NO KNOW. The assumptions start with the Malaysian military primary radar, when MH370 turned west and started to head back over the peninsula. I know that the Vietnamese military radar also reported a turn, but there is no way to be sure that this was MH370 that they were tracking, especially given the intermittent track of the Malaysian radar.

I am still trying to wrap my mind around the fuel and weight issues. MH370 left the gate with 19,100 kg of fuel which is about right for a fully loaded T7 to get to Beijing with considerable safety margin. Malaysian has never announced the take-off weight or the complete cargo manifest - only walkie -talkies, mangosteens and baggage. However, the fight departed with 50 empty seats, which is usually done to compensate for heavy cargo ( ie fully loaded), and the walkie-talkies should have flown out of Penang,

The calculations and recalculations of the Inmarsat .plots, getting further and further north are really straining credibility concerning fuel consumption. Of course we are only observers, and have no need to know.

Hi,

The fuel figure of 19100 kg you mention will be insufficient to complete a flight to Beijing. The authorities will have the flight plan that was generated on this particular flight so will know precisely what weights were involved.

The Boeing 772ER basic operating weight will be approx 140 tons.

Add on approx 2 tons for crew and approx 5 tons for pantry to generate a dry operating weight (DOW) of approx 147 tons.

You then add to the DOW the traffic load which is generated by the passenger, baggage and cargo weight which then gives you the zero fuel weight (ZFW)

Total passenger weight will be approx 17 tons.

Checked in bags will be approx 6 tons.

Let's assume a cargo weight of 5 tons.

This gives a ZFW of 175 tons.

To the ZFW you then add on the actual fuel required for the flight.

The fuel loaded will be in the region of 50 to 55 tons.

This aircraft will burn the following per hour at a cruise altitude of 35000 ft depending on the aircraft weight:

180 tons: 5600kg/hr

200 tons: 6200kg/hr

220 tons: 6800kg/hr

240 tons: 7300kg/hr

Hi,

Still no definitive information on whether the aircraft flew back across the Malaysian peninsula then North West bound or immediately turned South from the Vietnamese boundary.

A North West route then turning Southbound would be more likely deliberate action. The other scenario which would take it directly over Indonesia could possibly be multiple uncontrollable failures leading to loss of control.

If the aircraft had hit the ocean at high speed I would still expect debris to be visible somewhere by someone.

I did see a posting by someone on an aviation site who said there is in fact a circuit breaker for the cockpit voice recorder, but it is located in the lower electronics bay, not in the cockpit. Perhaps a 777 pilot here could verify that. It would truly be the final bizarre twist to this incident if the plane is recovered, and the cockpit voice recorder is.............blank.

Hi,

That is correct. The circuit breakers are not located in the flight deck for the CVR/FDR.

The CVR can be erased in the flight deck via the erase switch, but only on the ground with electrical power established and the brakes set.

I disagree with the notion that this aircraft could have been ditched intact.

US Airways Flight 1549 (A320, wingspan 112ft) ditching in the Hudson was one thing. Trying to put a 777 (wingspan 200ft) down in the middle of the ocean would be quite another. CAPT Sullenberger successfully ditched his aircraft on a calm river, and holes were torn in the fuselage even so. I don't think I've seen any informed guesses as to the sea conditions specifically in the areas which have been the focus of recent days' searching, but generally I have to guess that they couldn't have been anywhere near as benign as the Hudson River on the day of Sullenberger's ditching. It doesn't take much to catch a wing tip or the tail on a wave top; it's difficult enough even on smooth water. CAPT Shah's flying experience, though he WAS an instructor pilot, was not quite as extensive as Sullenberger, who is an ex-USAF fighter pilot who at the time of the accident had logged over 19660 hours, 4765 of them in type. He's also an air safety expert and glider pilot. Furthermore, if MH370 came down having run out of fuel and deadstick, perhaps without even a living pilot in the cockpit, and just hit the water in a steep glide (best case; nose-first worst case), I think it almost certain the aircraft would have been torn apart by the impact. ...torn apart to the extent that the remains consist of small pieces now widely dispersed, as TaH has suggested. Even if CAPT Shah was alive, and controlling the aircraft, under power, at the time of a ditching attempt, I'd consider the possibility of him doing it successfully beyond remote.

Agree 110%. I give you an A+.

Further back there's a quote of an "expert" who predicted that if the plane when in nose first and vertical, that the wings would tear off and sink, but the fuselage wouldn't be significantly harmed and would simply go into the water and sink. I throw the BS flag. It would have shattered to bits.

Somewhere else in this thread there's an article that says the typical wave height in that area is 5 meters, or 15 feet. So if you're alive and controlling the plane, what to you do? Land parallel to the waves and if so in the trough or try for a wave top, both of which are moving? Or do you land perpendicular to the waves and plow into them?

I think either would be impossible and would destroy the plane.

Well, there is training gouge, for smaller aircraft anyway, which dictates that you land parallel (and into the wind if possible, but more important not to nose into a swell). But hitting the surface of the water nose-first at somewhere around 200+ knots, or much more if actually in a steep dive, you might as well be smashing into a concrete wall. Literally. Don't know where the other poster got his information about just "shearing the wings off" and leaving the fuselage intact. That's pure fantasy and totally untrue.

Hi,

The B777 flight crew training manual states the following technique to adopt during ditching.

Fly at the appropriate reference speed, dictated by weight and flap setting. Descent rate of approx 200 to 300 feet per minute. Touchdown on the windward side, parallel to the waves or swell if possible. To accomplish the flare and touch down, rotate to the touch down attitude of 10 to 12 degrees nose up. Maintain airspeed and rate of descent with thrust. This obviously assumes a controlled ditching.

At 180 tons in weight the reference speed with flaps 30 will be 128 knots. At 200 tons the speed increases to 135 knots.

Hi,

Pretty cool video. Demanding day at work for the crews involved.

The video at 5:22 depicting the control surface movements is very good. Lots of input on the control wheel, column and rudder.

It's not just Thailand, so don't make out that it is.....last month I walked in to a bed shop. The sales guy was on his mobile, speaking in Hindi. I am familiar with Hindi so could tell he was talking to a mate about a girl. He looked at us and looked away, carrying on his conversation. I waited patiently for 5 minutes. He kept on glancing at me, but refused to put down the phone. I am fairly sure he is the kind of salesman who is on a measly retainer but a good commission. Next time he looked at me, I waved my Platinum card at him, smiled, and walked out. He was an idiot as I was fully intent on buying a big bed.

Should have just jumped into the bed until he was finished on the phone.

still no debris though to go with the pings

Yes.

I don't know what aviation experts say about whether a plane can be flown into the ocean without leaving a trace.

Not being an expert, it seems the best way would be to go in vertical.

But I'm not a pilot.

Hi,

I think with skill and lots of luck involved you could ditch fairly much intact, but some panels would no doubt come off during water contact. If so then why no attempt at getting out prior to sinking if passengers and crew still alive.

Hi,

Here is hoping it's the aircraft location.

Certainly further both North and East of where I expected.

There's 132 pages at the moment, would someone mind giving a quick synopsis of the current "theories" running around please . . . ?

Here are 10 - http://nypost.com/2014/03/19/top-10-theories-about-what-happened-to-flight-mh370/

Some more - http://www.huffingtonpost.co.uk/navjot-singh/post_7222_b_5056524.html

And if a conspiracy advocate, 12 of them here - http://www.rediff.com/news/slide-show/slide-show-1-10-weird-conspiracy-theories-on-flight-mh370/20140314.htm

Here's a "what if..."

What if there was a fire, the comms went down, the cockpit crew were overcome, but the autopilot was still on.

Is there a default heading that the autopilot would take if it could not communicate with other systems on the plane?

Would that be south?

thinking.gif

Hi,

The autopilot flight director system (AFDS) will continue to fly along the programmed route in the flight management computer using lateral navigation (LNAV) until it reaches the end of that route where it then will automatically change from LNAV to heading hold (HDG HOLD)

It will also maintain the current altitude/flight level if no pilot intervention.

It won't turn southbound unless the route is either programmed in that direction or the pilot selects heading or track select.