Missing Malaysia Airlines jet carrying 239 triggers Southeast Asia search

[F4UCorsair]

hawker, why do you contend that a controlled ditching would not have succeeded? Five years ago. Capt Sullenberger ditched an A320 very successfully on the Hudson River, and there have been others over the years, not recently of heavy category aircraft though. A B777 could handle quite rough water, i.e., it would not have to be river smooth, if flown well, and that would be with or without power from the engines.

An IAI Westwind was ditched off Norfolk Island a couple of years ago, at night, and all 6 aboard survived. See the report here http://www.atsb.gov.au/publications/investigation_reports/2009/aair/ao-2009-072.aspx

It has gotten to be a long thread, hasn't it. See #3527. 'Specifically addressed that comparison already. Apples & oranges, for a variety of reasons. And Sullenberger's accomplishment shouldn't be minimized. Most of his peers thought it nearly miraculous.

And the Westwind? Which would YOU rather try & ditch, having to dodge between even light swells at sea, a 13,500# aircraft with a 45ft wingspan, or a 400,000# aircraft with a 200ft wingspan?! (I'll bet the Westwind lands a little slower, too.) And the Westwind at Norfolk, in the controlled ditching you're referring to, broke in two.

Paste post # 3527

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.

Of course comparing a B777 with a Westwind is like comparing apples and oranges, but landing one of either on water (or land) isn't all that much different, and I'd guess that approach speeds aren't much different either, but I haven't bothered to check. The Westwind may be marginally less because because it doesn't have a swept wing, but the B777 has LED's and they reduce the approach speed significantly, typically 20+ knots less than with trailing edge flaps only. They both have V2's of about 140 knots, so approach speeds wouldn't be a lot different, and my guess would be not more than 15 knots, but certainly 20 as an outside figure.

The weight and size are irrelevant because the wing will effectively lift the weight of each and that's what is important. The B777, by virtue of its size, will handle much rougher water than a smaller aircraft. I would prefer to ditch a 777 than a Westwind.....anytime, same logic as crashing in a Lincoln Continental rather than a Morris 850; there's a lot more airframe to absorb impact forces.

I think you're placing way too much importance on experience levels. Based on straight experience, I should/would do a much better job than Sullenberger, but on the day, who knows?? There would be a lot of variables and unknowns to take into account, one of which would be that your butt hole would be puckering so fast that it would be cutting washers out of the seat. I think the ability to remain cool under enormous pressure, and that's part of the pilot psychological profile, would be a far greater attribute than experience. When we're considering actual manipulating ability, there is only so much 'experience', after which one doesn't improve any, or at all. When considering overall aeronautical experience, one never stops learning.

Yes, the Westwind did break in two on contact, but we don't know that the 777 didn't. What we do know of the 777 is that there has been no major wreckage spotted, but even from a few hundred feet, seat cushions are invisible, and that may be all that was released from the wreck if impact was gentle. I've participated in searches in years gone by, and even larger pieces can 'disappear' in water due to varying light conditions. Even on land wreckage can be difficult to see.

Edited April 11, 2014 by F4UCorsair

[P45Mustang]

MH 370 Black Box Found.

http://www.perthnow.com.au/news/unconfirmed-report-says-malaysia-airlines-flight-mh370-black-box-has-been-found/story-fniztvnf-1226880483186

Search coordinators say there has been no major breakthrough in the search for missing Malaysia Airlines flight MH370, contradicting prime minister Tony Abbott's comments that authorities were confident they know the location of the black box.

http://news.ninemsn.com.au/world/2014/04/11/13/10/mh370-black-box-within-reach-abbott

11 April 2014 Last updated at 03:47

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Missing plane MH370: Abbott 'confident' over signals

http://www.bbc.com/news/world-asia-26984162

Thai news is reporting the same. So it must be correct.

[NanLaew]

The inital discovery report was Tweeted by aviation expert Geoffrey Thomas, the editor-n-chief of the website airlineratings.com and executive editor of AirlineReview.com.

I mean look at this guys credentials. He runs a couple of lower-order airline rating websites.

... Echo has come along and done a radar scan, an echo scan if you like...

What on earth is a 'radar scan' or 'echo scan'? Radar only works in air AFAIK and the underwater bits are best done by sonar.

... Don’t forget, the ocean floor is all silt, a big object like a 250 tonne aeroplane, it is going to give you a different shaped return, rather than a softer return.

The topography in the water depths of the search area is UNKNOWN. The assumption of it being 'all silt' is laughable.

Oh... he only TWEETED his expert opinion. Say no more!

You would think that there's an election imminent the way that Tony Abbott is latching onto all these 'breaking news' non-events. In contrast, the much pilloried Malaysian acting Transport Minister Hishammuddin Hussein is much more circumspect these days and nothing less than physical wreckage from the doomed plane is going to make him say anything silly (again).

[P45Mustang]

The inital discovery report was Tweeted by aviation expert Geoffrey Thomas, the editor-n-chief of the website airlineratings.com and executive editor of AirlineReview.com.

I mean look at this guys credentials. He runs a couple of lower-order airline rating websites.

... Echo has come along and done a radar scan, an echo scan if you like...

What on earth is a 'radar scan' or 'echo scan'? Radar only works in air AFAIK and the underwater bits are best done by sonar.

... Don’t forget, the ocean floor is all silt, a big object like a 250 tonne aeroplane, it is going to give you a different shaped return, rather than a softer return.

The topography in the water depths of the search area is UNKNOWN. The assumption of it being 'all silt' is laughable.

Oh... he only TWEETED his expert opinion. Say no more!

You would think that there's an election imminent the way that Tony Abbott is latching onto all these 'breaking news' non-events. In contrast, the much pilloried Malaysian acting Transport Minister Hishammuddin Hussein is much more circumspect these days and nothing less than physical wreckage from the doomed plane is going to make him say anything silly (again).

A somewhat cynical view, if I might be so bold.

[F4UCorsair]

The inital discovery report was Tweeted by aviation expert Geoffrey Thomas, the editor-n-chief of the website airlineratings.com and executive editor of AirlineReview.com.

I mean look at this guys credentials. He runs a couple of lower-order airline rating websites.

... Echo has come along and done a radar scan, an echo scan if you like...

What on earth is a 'radar scan' or 'echo scan'? Radar only works in air AFAIK and the underwater bits are best done by sonar.

... Don’t forget, the ocean floor is all silt, a big object like a 250 tonne aeroplane, it is going to give you a different shaped return, rather than a softer return.

The topography in the water depths of the search area is UNKNOWN. The assumption of it being 'all silt' is laughable.

Oh... he only TWEETED his expert opinion. Say no more!

You would think that there's an election imminent the way that Tony Abbott is latching onto all these 'breaking news' non-events. In contrast, the much pilloried Malaysian acting Transport Minister Hishammuddin Hussein is much more circumspect these days and nothing less than physical wreckage from the doomed plane is going to make him say anything silly (again).

I would take anything he, a self styled aviation 'expert', said, with a grain of salt.

He is editor of an aviation magazine and therefore running an agenda.

A very brief search of aviation books written by him throws up "Passengers who Make Your Life Hell"... That's deep aviation knowledge!!

Edited April 11, 2014 by F4UCorsair

[tigermonkey]

hawker, why do you contend that a controlled ditching would not have succeeded? Five years ago. Capt Sullenberger ditched an A320 very successfully on the Hudson River, and there have been others over the years, not recently of heavy category aircraft though. A B777 could handle quite rough water, i.e., it would not have to be river smooth, if flown well, and that would be with or without power from the engines.

An IAI Westwind was ditched off Norfolk Island a couple of years ago, at night, and all 6 aboard survived. See the report here http://www.atsb.gov.au/publications/investigation_reports/2009/aair/ao-2009-072.aspx

It has gotten to be a long thread, hasn't it. See #3527. 'Specifically addressed that comparison already. Apples & oranges, for a variety of reasons. And Sullenberger's accomplishment shouldn't be minimized. Most of his peers thought it nearly miraculous.

And the Westwind? Which would YOU rather try & ditch, having to dodge between even light swells at sea, a 13,500# aircraft with a 45ft wingspan, or a 400,000# aircraft with a 200ft wingspan?! (I'll bet the Westwind lands a little slower, too.) And the Westwind at Norfolk, in the controlled ditching you're referring to, broke in two.

Actually the landing speeds of the Westwind and T7 are surprisingly similar, but the Westwind is marginally slower. The other large difference is that the Westwind wings are mounted higher and further back in the fuselage, and the Westwind has tail mounted engines. One could reasonably expect when ditching a Westwind that you could first contact the water with the fuselage - this is not so with the T7, where (if you miraculously avoided catching a wing-tip on a swell) your first significant water contact would be with one or both of the engine pods.

Capt. Sullenberger's ditch on the Hudson is called the 'Miracle on the Hudson' with very good reason - it was just that. The only other successful ditch of a heavy jet was the ditching of an RAF Nimrod ( military version of the Comet ) in 1995 in dead calm seas, but still the tail broke off. The Nimrod/Comet did not have a problem with engine pods hitting the water, since the Nimrod's engines were built into the base of the wings.

[P45Mustang]

Tony Abbott has got bigger fish on his plate than his aviation magazine.

Check out his conversations with PRC media.

[Tywais]

A post and replies to it removed due to no link to news source that was quoted. Due to copyright issues, please leave a link to any quotes from news or other sources.

[P45Mustang]

Looking forward to the black box being found asap.

And the cargo.

Dream on...

Will do cobber.

[F4UCorsair]

Note: This post is just to put things in perspective regarding one theory of a water landing.

Example of an ocean landing when it ran out of fuel, this is the Ethiopian Airlines Flight 961 hijacking. Even though it appears to be a fairly slow water landing attempt, the damage was catastrophic. So not so easy to get it down in one piece by attempting to ocean land it.

It wasn't easy for that pilot, being bashed around the head with a fire extinguisher by one of the hijackers.

If that aircraft had ditched in a wings level attitude, it wouldn't have been nearly so catastrophic.

Notice how the pilot attempted to put it down near land ? Making a salvage/ rescue operation timely and with limited logistical problems. That isn't the case with 370.

You need to read a little more of the history of this flight.

The hijackers wanted the aircraft to fly to Australia. The crew discreetly turned it back toward land so that they had a greater chance of rescue when it inevitably ran out of fuel.

If the Captain hadn't been copping a fire extinguisher around the ears at the time, it may well have been a better landing. Fortunately the hijackers were all killed on impact, and unfortunately quite a number of pax were also.

[webfact]

Australian PM 'very confident' signals are from MH370
Agence France-Presse
SYDNEY

SYDNEY: -- Australian Prime Minister Tony Abbott said Friday he was "very confident" that signals detected in the search for missing Malaysia Airlines Flight MH370 were from the aircraft's black box.

"We have very much narrowed down the search area and we are very confident that the signals that we are detecting are from the black box," Abbott said from China.

Australia has been leading the search for the Boeing 777 aircraft, which went missing on March 8 en route from Kuala Lumpur to Beijing, ever since the operation was moved to the Indian Ocean.

More than 100 flights over the remote area off western Australia have so far failed to return a single piece of debris from the plane, but four signals or "pings" linked to aircraft beacons have been detected by an Australian ship.

The first two of these, which were picked up by the Australian vessel Ocean Shield using US equipment, have been analysed as being consistent with those from black box data recorders.

Speaking in Shanghai, Abbott said the search area had now been "very much narrowed down because we’ve now had a series of detections, some for quite a long period of time".

"Nevertheless, we’re getting to the stage where the signal from what we are very confident is the black box is starting to fade," he said.

"We are hoping to get as much information as we can before the signal finally expires."

Abbott said he did not want to go into any further detail until he had briefed Chinese President Xi Jinping on the investigation. Some two-thirds of the 239 people onboard Flight MH370 were Chinese.

But he did elaborate on his confidence.

"We are confident that we know the position of the black box flight recorder to within some kilometres.

"But confidence in the approximate position of the black box is not the same as recovering wreckage from almost 4.5 kilometres beneath the sea or finally determining all that happened on that flight."

Abbott also offered support for Chinese relatives mourning loved ones lost in the tragedy.

"I grieve with all the bereaved, especially the family and friends of the 154 Chinese victims, and I offer them the assurance that Australia will not rest until we have done everything we can to provide comfort and closure," he said.


-- The Nation 2014-04-11

[hawker9000]

The weight and size are irrelevant because the wing will effectively lift the weight of each and that's what is important. The B777, by virtue of its size, will handle much rougher water than a smaller aircraft. I would prefer to ditch a 777 than a Westwind.....anytime, same logic as crashing in a Lincoln Continental rather than a Morris 850; there's a lot more airframe to absorb impact forces.

'Couldn't disagree more. Weight & size have absolutely everything to do with it, and not a matter of the lift involved at all. Both aircraft keep flying until one or both wings stall or there's an impact. Once contact with the water begins, F=ma. And it's not a matter of a "collision" with another vehicle, like a car; in this case the other vehicle is (for all intents & purposes) the infinitely massive ocean. Also disagree categorically with your statement that "the B777, by virtue of its size, will handle much rougher water than a smaller aircraft" (which would be true of a larger ship, but not a larger aircraft...), although NEITHER would likely do well in rough seas actually. Once afloat, if that can be achieved, the larger aircraft would "ride" better (and possibly float longer even), that's true, but that's not the issue.

Think of it this way:

- Rest both aircraft on a fulcrum located at the CG. Which aircraft experiences the greater breaking force and which one has the greater moment arm at nose & tail? Keep in mind that the larger aircraft not only weighs 3x (or more) as much, but has a nose & tail that extend much farther from that fulcrum.

- Suddenly "trap" the tail with the aircraft pitched up at high AOA at landing speed. Downward pitching moment, and pitch rate (or "descent rate" - whichever way you want to look at it) at the nose, and impact force when the nose hits the ground, is greater in which aircraft? (Assuming the tail doesn't fold up, start twisting, or just rip right off, in which case we have disintegration beginning...)

- Again, suddenly "trap" the tail with the aircraft at landing speed. What's the force trying to rip off the tail of the large massive airplane vs the smaller less massive airplane?

- Which wing would you rather be trying to avoid wave tops with, the one that extends 100ft left & right, or the one that extends 22ft left & right?

I have never ditched, but I sure know about arrested landings. (And I also know what happens when a plane engages the wire while still airborne, too [due to excessive pitch angle - "inflight engagement"]). Not pretty - probably doesn't happen much anymore though. And THOSE are aircraft made to take the sudden deceleration of arrestment, the increased rate of descent at touchdown, and a lot more punishment generally. 'Know a tiny bit about mishap investigations, too, including a couple of Class 'A's, way back in another life.

Well anyway, 'not going to resolve these disagreements here I don't expect. And we're talking about impact events characterized partly by chaos & randomness to be sure, But if I ever find myself hoping to survive one of these events myself, I'll definitely take the Westwind (preferably on a much calmer surface than the southern Indian Ocean) thank-you very much. And I'm not expecting them to find any "large metal tubes" resting sedately on the sea floor, or any large anything really, that were once MH370. Provided this is where the flight really went down, some bits & pieces might start washing up on distant IO beaches somewhere someday.

Edited April 11, 2014 by hawker9000

[aguy30]

Australian Air Chief Marshal Angus Houston: "On the information I have available to me, there has been no major breakthrough in the search for MH370. I will provide a further update if, and when, further information becomes available'

Australian Prime Minister Tony Abbott said Friday he was "very confident" that signals detected in the search for missing Malaysia Airlines Flight MH370 were from the aircraft's black box.

Tony Abbott seems to have all the qualifications of a Thai politician. Guess he didn't bother to consult with the man that should have the latest info. Open mouth, say whatever and no need to have any facts to support statements.

Edited April 11, 2014 by aguy30

[GentlemanJim]

After catching up on the last 4 pages I have to say that from now on I know I can travel by air in absolute confidence that I am safer than I have ever been. In the unlikely event that both pilots suffer a heart attack there will be so many experts down the back that we will have enough volunteers to fly us out of any given situation. I reflect and wonder why I did all those endless years of training and specialist simulator sessions and constant ground exam work to over degree level even when in my 50's when there are so many out there to whom this is all a piece of piss.

Thailand, hub of expat experts in everything

Edited April 11, 2014 by GentlemanJim

[hawker9000]

After catching up on the last 4 pages I have to say that from now on I know I can travel by air in absolute confidence that I am safer than I have ever been. In the unlikely event that both pilots suffer a heart attack there will be so many experts down the back that we will have enough volunteers to fly us out of any given situation. I reflect and wonder why I did all those endless years of training and specialist simulator sessions and constant ground exam work to over degree level even when in my 50's when there are so many out there to whom this is all a piece of piss.

Thailand, hub of expat experts in everything

You did all that training & simulator work just in hopes of being called to the cockpit to save the day someday? What a guy! A real hero.

Actually, I actually think a great many people (not saying everybody, but many) would be capable of being talked down in perhaps most of today's airliners if not prone to panic and able to follow instructions by radio calmly. Do flight attendants get any such "contingency" training at all?

Hub of experts & know-it-alls, yeah, maybe, but definitely lurk-central for snarky cynics (who actually just want us to know that they know more than the know-it-alls, but are just more "humble" about it).

[P45Mustang]

Yep.

Never mind Sherlock.

Looks like a case for Colonel Custard to me.

Don't tell Malaysia or the PRC though.

Answer is in the box

[P45Mustang]

I think it was suicide, or an act of revenge (possibly related to treatment of ethnic minorities), btw.

Just a hunch.

Anyway, back to the story.

[Thaiready]

Australian Air Chief Marshal Angus Houston: "On the information I have available to me, there has been no major breakthrough in the search for MH370. I will provide a further update if, and when, further information becomes available'

Australian Prime Minister Tony Abbott said Friday he was "very confident" that signals detected in the search for missing Malaysia Airlines Flight MH370 were from the aircraft's black box.

Tony Abbott seems to have all the qualifications of a Thai politician. Guess he didn't bother to consult with the man that should have the latest info. Open mouth, say whatever and no need to have any facts to support statements.

he just wants to get his 2 cents worth in

[P45Mustang]

Meanwhile Aussies who may or may not vote for him are looking for the box.

Abbott bashing is not part of the main story mate.

[GentlemanJim]

<script type='text/javascript'>window.mod_pagespeed_start = Number(new Date());</script>

After catching up on the last 4 pages I have to say that from now on I know I can travel by air in absolute confidence that I am safer than I have ever been. In the unlikely event that both pilots suffer a heart attack there will be so many experts down the back that we will have enough volunteers to fly us out of any given situation. I reflect and wonder why I did all those endless years of training and specialist simulator sessions and constant ground exam work to over degree level even when in my 50's when there are so many out there to whom this is all a piece of piss.

Thailand, hub of expat experts in everything

You did all that training & simulator work just in hopes of being called to the cockpit to save the day someday? What a guy! A real hero.

Actually, I actually think a great many people (not saying everybody, but many) would be capable of being talked down in perhaps most of today's airliners if not prone to panic and able to follow instructions by radio calmly. Do flight attendants get any such "contingency" training at all?

Hub of experts & know-it-alls, yeah, maybe, but definitely lurk-central for snarky cynics (who actually just want us to know that they know more than the know-it-alls, but are just more "humble" about it).

How funny, and I was referring to if I should be one of those who suffer the heart attack. Actually I wasn't referring to posts by you or Mustang who seems to like your response, but as you have taken offence and replied with a personally aimed attack then go take a hike.

Edited April 11, 2014 by GentlemanJim

[RubbaJohnny]

After catching up on the last 4 pages I have to say that from now on I know I can travel by air in absolute confidence that I am safer than I have ever been. In the unlikely event that both pilots suffer a heart attack there will be so many experts down the back that we will have enough volunteers to fly us out of any given situation. I reflect and wonder why I did all those endless years of training and specialist simulator sessions and constant ground exam work to over degree level even when in my 50's when there are so many out there to whom this is all a piece of piss.

Thailand, hub of expat experts in everything

Don't let the Hub all bubble deter you Jim there's pub grub for drub club the know -alls will have to wait for the sub,there's the rub?

I guess only some DNA or the flight recorder will assauge the mob.

I've no technical insight but I guess with endles time and technolgy if it is there it can be found like theAntikythera machine,the titanic ,Marie Rose or Air France,assuming the pack is looking in the right area.

If it is on land,vaporized (is that possible by lightening ,meteor,laser) or other area of sea may never be found.

It's going to break Malayisa airlines and they can hardly tell the poor relatives they'll quit searching however long it takes?

[P45Mustang]

Are you suggesting the topic should be closed RJ?

[RubbaJohnny]

Knot at haul

[boomerangutang]

After catching up on the last 4 pages I have to say that from now on I know I can travel by air in absolute confidence that I am safer than I have ever been. In the unlikely event that both pilots suffer a heart attack there will be so many experts down the back that we will have enough volunteers to fly us out of any given situation. I reflect and wonder why I did all those endless years of training and specialist simulator sessions and constant ground exam work to over degree level even when in my 50's when there are so many out there to whom this is all a piece of piss. Thailand, hub of expat experts in everything

That's much of what T.Visa is about; a venue to enable anyone to vent and/or offer opinions. If there was a lunar landing that went awry, all types of folks might comment, not just astronauts trained in piloting lunar modules. You too GJ, if you like. Though I'd rather have a pilot piloting a plane that I'm riding in, pilots can make mistakes also. They're human, and some get drunk before a flight. The biggest mistake is suicide with a people-laden plane - which happened with Egypt Air 990 pilot's suicide/mass murder. Though extremely rare, it's not impossible.

A small news item today mentioned how, just two or 3 weeks ago, an Air India flight flying SW over Germany, didn't respond at all to ground control. Apparently both the pilot and co-pilot had taken off their head-sets and neglected to turn up the intercom. Both were suspended for 2 weeks. Do I need to be an adept pilot to report such an event?

Edited April 11, 2014 by boomerangutang

[HerIndoors]

Aah ... the supository of wisdom speaks. (In joke for Aussies who heard one of his speeches).

[GentlemanJim]

Are you suggesting the topic should be closed RJ?

Well you know what they say about when everything has been said that can be said and when nobody has anything to add that is remotely worthwhile...why not. Until reliable, credible information is released concerning this tragedy this thread has become a bit of a hamster wheel.

[P45Mustang]

Are you suggesting the topic should be closed RJ?

Well you know what they say about when everything has been said that can be said and when nobody has anything to add that is remotely worthwhile...why not. Until reliable, credible information is released concerning this tragedy this thread has become a bit of a hamster wheel.

Keep up GJ.

Events are unfolding.

BTW. I'm not a pilot, a pilot wannabe, or an aviation 'expert'.

[Tywais]

Are you suggesting the topic should be closed RJ?

Well you know what they say about when everything has been said that can be said and when nobody has anything to add that is remotely worthwhile...why not. Until reliable, credible information is released concerning this tragedy this thread has become a bit of a hamster wheel.

This topic is not going to be closed anytime soon guys. I try to update it with new information everyday when I can find it. A little 'chit chat' doesn't hurt in between but would like things to stop getting too personal though.

[P45Mustang]

Aah ... the supository of wisdom speaks. (In joke for Aussies who heard one of his speeches).

Hilarious.

[Tywais]

Lot of conflicting reports:

From PM Abbot: He told reporters in China: "We have very much narrowed down the search area and we are very confident the signals are from the black box."

http://www.mirror.co.uk/news/world-news/flight-mh370-black-box-found-3398513#ixzz2yZXJs53k

However:

Here's Retired Air Chief Marshal Angus Houston's full statement about the signals detected on Thursday.

The pings are not believed to be from MH370's black boxes, which have sunk to a depth of around five kilometres below the surface.