Civil Aviation Development & Discussion

Suraj · Post by **Suraj** » 18 Jun 2013 06:51

Rumors apart, Jet doesn't have a whole lot of leverage here. They're backing out of their international network, in favor of feeding Etihad at Abu Dhabi from various Indian points, in exchange for significant financial backing from them. This helps Etihad avoid the hurdles Emirates faces, where their increasing access to the Indian market caused friction with domestic carriers lacking their clout and reach, as well as their Dubai hub operations. If Emirates is further squeezed out of Indian ports, they might strike a similar deal with another Indian carrier, if not try to swing Jet over to them, to do what Etihad and Jet just agreed to do.

Singha · Post by **Singha** » 18 Jun 2013 07:19

Jet needed a financial lifeline and got it. Etihad will over time increase stake to 49% for sure and be in drivers seat officially.

Spicejet could be a good domestic candidate for Emirates or Qatar airlines to tie with...I have heard emirates is quite expensive compared to the other two though.

lets not discuss air india here, it failed to catch the boat even with huge cash infusions and the gulf airlines with deep pockets & hubs built a worldwide network from out of nowhere in just one decade.

my only hope for a indian airline to eventually attain global scale is Indigo. hope they keep eyes on ball and clear of trouble. first become #1 in India and then carefully expand via tieups and codeshares if need be.

Bade · Post by **Bade** » 18 Jun 2013 07:36

Has any large airline anywhere survived without some form of state largesse. The mid-east ones are essentially state run enterprises aren't they with their oil wealth helping them to invest into a bottomless pit with minimum pain.

Singha · Post by **Singha** » 18 Jun 2013 10:23

air asia maybe ? it has a huge regional network in ASEAN and uses only 737 sized planes.
http://www.airlineroutemaps.com/East_As ... irAsia.gif

being KL based the price of fuel might be good there. price of petrol in malaysia is said to be quite cheap. plus the east asians do the hub thing well (singapore, KL, bangkok, seoul, taipei, HK....) unlike our AAI munnas.

SSridhar · Post by **SSridhar** » 18 Jun 2013 10:50

It is painful to keep reporting one bad news after another about the new Chennai Domestic airport, but it needs to be done.

Not Enough Seats at New Terminal: Fliers - The Hindu

Too few chairs, and they’re all taken far too quickly — this is the latest complaint of passengers at Chennai airport. Frequent fliers said during peak hours, several passengers at the departure level of the new domestic terminal were forced to do without a seat, as all the chairs were invariably taken.

Devika Parashar, 33, a software professional based in Chennai said she was forced to stand for half an hour near the check-in area on her recent trip to Bangalore. “I left home early to avoid traffic and got to the airport before my colleague. Since I wanted to check-in only after my colleague arrived, I had to wait at the check-in area for nearly 30 minutes without a seat as the terminal was quite crowded then. Is it too much to ask for seating inside the terminal?” she asked.

D. Sudhakar Reddy of Air Passengers’ Association of India said he had received several complaints from passengers on the inadequate seating arrangements at the new domestic terminal. “The quality of the chairs too, could be better, considering the amount of money spent,” he said.

The presence of a standalone X-ray machine has also eaten away at space where chairs could have been provided, said an Airports Authority of India official. “There are more than enough chairs at the security area to cater to passengers even during peak hours. It is seating at the check-in area that passengers complain about,” he said.

Another AAI official however said the number of chairs provided at the check-in area was just sufficient. “There are fewer chairs here to discourage people from hanging about in the area,” he said. {I don't understand. Check-in area is meant for genuine passengers who are probably waiting for the counters to open. Yet, AAI does not want to provide them seating facilities ? Are they just hanging about there for fun ? Such is the arrogance of the AAI. Throw out this wretched AAI from designing , executing and managing airports.}

Singha · Post by **Singha** » 18 Jun 2013 12:30

lack of seats is there in both checkin and security areas of BIAL also.

SSridhar · Post by **SSridhar** » 25 Jun 2013 17:05

Two more Glass Panels Crack at Chennai Airport Domestic Terminal - The Hindu

Two more glass panels have cracked near the arrival halls of the new domestic terminal at the Chennai airport. Just a month ago, The Hindu reported about the cracking of close to 10 glass panels in the air side of the new domestic and international terminals of the airport. Officials of the Airports Authority of India (AAI) said that the cracked panels were subsequently replaced.

Now, it has been found that two more glass panels in the new domestic terminal have developed cracks. Officials and experts say that this may be a case of engineering defect. “One of the glass panels has had cracks for a while now; the second one may have been recent. It looks like the panels were not fixed intact during the construction which may have caused the cracks on the panels,” said an AAI official.

This may continue to happen for a couple of months since the building is fairly new and the glass panels need time to stabilize, he added.

“We purchased the glass panels from Saint Gobain. After there were complaints about cracked panels we sent the samples of the panels for testing and we are yet to rule out what the exact cause is for this problem. One of the issues could be the impurities present in the glass. We will replace the cracked one soon and will take steps to ensure safety,” said another official.

However, officials of Saint Gobain said that they have supplied glass to Bangalore airport and they were no such complaints in that airport. “I don’t think impurities alone can cause such breaking of panels since we ensure that they are of high quality. Undue stress laid on the glass panels during fixation could be one of the main reasons that may have led to this problem,” said an official of Saint Gobain.

Kamal Dasgupta, acting director of Central Glass and Ceramic Research Institute said, "It is difficult to say what caused the glass panels to crack without testing it. While glass usually has impurities of varying quantities, the impurity alone may not cause the glass to break. Any mechanical stress developed will help in accelerating the cracking process. One of the reasons also could be the improper fitting of the glass panels."

Kolkata airport, another AAI-run airport, too has had several glass panels developing cracks. {Both Kolkatta & Chennai were by the AAI. That is why}

A structural engineering expert from IIT Madras said the cracks developed only because of structural and engineering deficiency.

“Glass cannot develop cracks on its own since it is manufactured after a highly rigorous and mechanised process. There is definitely an engineering defect which must have led to this problem. The glass may not have been properly cushioned within the frame,” he said.

Built at a cost of over Rs. 2,000 crore, it was only in January that the new terminals were inaugurated. The domestic terminal which was thrown open for public use in April also developed problems of false ceiling collapse in mid-May.

Sushupti · Post by **Sushupti** » 02 Jul 2013 04:38

Sushupti · Post by **Sushupti** » 02 Jul 2013 04:46

Government of India could not trace the owner of Jet Airways

http://bharatian.wordpress.com/2011/01/ ... t-airways/

Sushupti · Post by **Sushupti** » 02 Jul 2013 05:10

Watch TSR Subramaniam, ex-cabinet secretary, in PArt-III (This is no way to run democracy)

Debate: Big fight over big deal?

Part-I
http://www.timesnow.tv/Debate-Big-fight ... 431084.cms

Part-II
http://www.timesnow.tv/Debate-Big-fight ... 431085.cms

Part-III
http://www.timesnow.tv/videoshow/4431086.cms

Sushupti · Post by **Sushupti** » 02 Jul 2013 21:02

ABU DHABI CIVIL AVIATION: RAISING THE PROFILE

http://www.wikileaks.org/plusd/cables/0 ... 966_a.html

Sushupti · Post by **Sushupti** » 02 Jul 2013 22:06

Austin · Post by **Austin** » 04 Jul 2013 19:23

Indian airliner to hire female-only cabin crew to save on fuel costs

Indian low-cost airline GoAir has calculated it could save more than $500,000 a year by hiring a female-only cabin crew, as women are on average 20kg lighter than men.

In a move to trim fuel costs, the airline is considering putting a hiring freeze on heavier male cabin crew applicants in favor of lightening the airplane load.

40 percent of GoAir’s current crew members are male, and will continue their contacts with the airline.

"We are looking at every possible way of cost-cutting to remain profitable," Giorgio De Roni, the company’s chief executive, told the Times of India.

The airline wants to expand its 15 aircraft fleet to 80, and employ a total of 2,000 cabin crew and pilots, and burning less fuel, they believe, will help them achieve this aim quicker.

GoAir has implemented similar weight-saving tactics as other airlines- luggage fees, lighter in-flight magazines and blankets, and less food and drink on board.

GoAir’s new aircraft will help reduce the fuel used by 5 percent by installing ‘sharklets’, or wingtip devices.

Rupee rut

The rupee’s sharp fall against the dollar has tightened the airline’s budget, coupled with rising jet fuel prices, the Times of India reported.

"The rupee's fall has hurt the industry badly. All major expenses – aircraft leasing, spare parts and fuel costs – are linked to the dollar," De Roni told the Times of India.

The rupee has lost more than 8 percent against the dollar so far this year, and it dropped below 60 against the dollar to 59.911 early Thursday, continuing its decline.

India’s fiscal deficit , and the weak rupee, will continue to drop when the US Federal Reserve cuts back on stimulus spending.

Jet fuel prices have provided a challenge for the entire airline industry, which has created a demand for new aerodynamic and fuel efficient technology.

chaanakya · Post by **chaanakya** » 07 Jul 2013 01:35

Boing 777 crashes in SF. Looks skidding. Emergency chute deployed. debris seems scattered around but plane lower body is intact and foam fire tenders used. Upper skin seems totally burnt out . No word of casualty details yet. Fireball after large pop sound as per witness. looks tragic

Hope Bhai Relatives and Friends are safe.

Asiana Airlines Flt 214 from SoKo

chaanakya · Post by **chaanakya** » 07 Jul 2013 01:54

Twitter from one survivor

https://path.com/p/1lwrZb

I just crash landed at SFO. Tail ripped off. Most everyone seems fine. I'm ok. Surreal...
— David Eun at San Francisco International Airport (SFO) (Airport)

photo shows survivors walking off before plane is engulfed in fire and upper part destroyed . cockpit seems intact.

saip · Post by **saip** » 07 Jul 2013 02:18

I may be wrong but I thought I saw a passenger dragging a carryon.

nachiket · Post by **nachiket** » 07 Jul 2013 02:41

This'll be the second serious accident for the 777 after British Airways 38 which also crashed while landing after losing thrust in both engines. (There was another which burned on the ground with no casualties). There were no fatalities in flight 38 and it is unclear whether there are any today. Hope everybody escaped unhurt.

manish · Post by **manish** » 07 Jul 2013 09:45

nachiket wrote:This'll be the second serious accident for the 777 after British Airways 38 which also crashed while landing after losing thrust in both engines. (There was another which burned on the ground with no casualties). There were no fatalities in flight 38 and it is unclear whether there are any today. Hope everybody escaped unhurt.

Looks like a RWY undershoot for whatever reason.

People citing FlightAware tracking reports of the flight say that the plane had slowed down to an abnormally low 98kts at the start of its final approach.

Now some reports are claiming upto 3 casualties and several more critically injured.

chaanakya · Post by **chaanakya** » 07 Jul 2013 11:22

looks like plane stalled and undershot the runway, going by one passenger account.
Tail section broke off and in one of the pictures seen around runway splintered in many pieces.
One engine , left side perhaps detached , while right one still attached to the body.
Undercarriage was deployed and probably hit the concrete at runway edge on waterfront, one piece seen on runway. Plane was on it belly for sure.
Power loss could be one reason for low speed and loss of height and stalling just above runway edge.

Except two/three all others including crew are safe.
Fire breakout was after most of the passengers got off the plane. Lucky escape for them.

manish · Post by **manish** » 07 Jul 2013 12:13

If confirmed, these will be the first fatalities ever related to the B777 in the 18+ years that the type has been in service with around 1100+ doing duty around the world on longhaul routes.

Shows how far technology has come with regards to aviation safety.

RIP to the dead.

chaanakya · Post by **chaanakya** » 07 Jul 2013 12:34

For 777-300
Landing threshold speed Vat is 135-145 knots full flap. gear down . Reported speed of 98 Knots is certainly stalled plane dropping dead. It would not have captured glideslope , generally , from below by increasing the speed and then descending . If ILS was off then it would have performed non precision approach, which is ok as visibility was reported to be 10 km.

May the dead attain moksha.
Passengers had miraculous escape.

chaanakya · Post by **chaanakya** » 07 Jul 2013 13:03

This is an excellent landing sequence on Airbus 380 at SF

chaanakya · Post by **chaanakya** » 07 Jul 2013 14:03

And perhaps the plane that met its end finally
Asiana Airlines Boeing 777-200 landing at SFO

SriKumar · Post by **SriKumar** » 07 Jul 2013 22:03

Following some pilot discussion fora. Seems like PAPI (a color-based light system showing pilots the right glide slope) was shut down at SFO (atleast for that runway). So one basic visual indicator out. There were some passenger accounts that the engines were revved up at the last moment (too late of course), but this suggests that the engines were running fine. Also, CEO of Asiana gave a public statement that aircraft and engines were fine. Flight started in Shanghai, which means about 1.5 hours flight + 2 hours wait time = about 4 more hours of flying added to the 10 hours of flight time for pilots. The airframe took a solid beating and stayed intact and kept people inside the fuselage (except for the 2 unfortunate souls RIP)......Also, the passengers had time to get out before the fire enveloped part of the plane...those precious minutes saved a lot of lives.

Have to hand it to the emergency rescue personnel. Alteast 50 passengers were injured critically (out of 181 who were injured).....which means many could not get out on their own and probably had to be bodily evacuated . These guys got out all the injured within the few minutes they had before the plane burnt out. I am guessing they had about 3-5 minutes max to get everyone out...probably less than that since there was a fireball upon impact so a fire had already started. Well-trained and committed professionals....these guys.

Lots of witnesses (pilots and passengers) and pictorial/camera evidence, black box information etc. The investigation should be conclusive.

Added later: 123 people 'walked away', which means around 180 persons were evacuated by the rescue personnel.

San Francisco Fire Chief Joanne Hayes-White agreed. "I was near the plane and took a look inside," she told reporters Sunday. "It was nothing short of a miracle that we had literally 123 people walk away from this."

Suraj · Post by **Suraj** » 08 Jul 2013 08:54

There were two flight crews on board. Apparently the captain during the landing was new to the type (B777) but had lots of experience with B747 jumbos. The FO was an experienced B777 operator. However, Korean cockpit hierarchy is such that FO may have been careful to avoid overruling the captain.

The previous two crashlandings (BA38 at London, AF358 at Toronto which was an Airbus A340) both had no casualties. However, they both apparently landed much more softly, in relative terms. This was a pretty hard crash. Seeing the amateur video of the landing, the whole fuselage bounced up and down as it spun off the runway. I would not be surprised if the serious injuries were up front among the first and business class passengers, despite the plane hitting its tail on landing. The two deceased women were seated in the front/middle, from reports.

Theo_Fidel · Post by **Theo_Fidel** » 08 Jul 2013 11:17

Anyone know or can describe what this 'slam dunk' ATC approach is.
There is much speculation that this was an accident waiting to happen but this jargon seems very mysterious.
TIA

reports are the women/girls were in the back. More confusion...

chaanakya · Post by **chaanakya** » 08 Jul 2013 11:55

Slam Dunk

http://www.airliners.net/aviation-forum ... in/702629/

Slam dunking, for those that do not know is when a plane is coming in "high" on approach, and then rather than do a "go-around", the last 3 or 4 ground miles of final approach, the pilot almost literally puts the plane into a nose dive (pitched down 30 degrees or more) and then levels off and flares just before or just as he crosses the runway numbers.

chetak · Post by **chetak** » 08 Jul 2013 13:32

Amateur video of the actual crash at San Francisco..........

Theo_Fidel · Post by **Theo_Fidel** » 08 Jul 2013 20:37

Thanx chanakya,

That sounds incredibly challenging. 30 degree nose down. How the hell do they pull that off with A380 type craft?

Kannan · Post by **Kannan** » 09 Jul 2013 07:53

The media is just making everything seem crazy to get the links clicked on.

It is not unusual to land the aircraft without ten fancy instruments. You don't need to depend on ILS to land a plane. Typically you'd capture the glideslope from below and begin your descent, but there's no reason not to do a visual approach on a day like that.

It also isn't unusual for someone with few hours in type carrying passengers for hire. Who can afford to fly around empty 777s building time? Plus, they had quite a few senior pilots in that flight deck.

At the end of the day, a professional crew with that much flight time in clear skies and amazing visibility should be able to determine that their aircraft is sinking too fast to reach the runway without having so many automated crutches. I empathize with them because they erred, which is human, but I don't think that changes my previous statement.

RIP

SriKumar · Post by **SriKumar** » 09 Jul 2013 09:12

^^^ Seems like the pilot with low time on 777 was the captain on this flight? And it was the junior pilot who had more experience on the type? But somehow that experience did not come into play in the flight deck in the last 30 seconds. A lot of speculation going on (in some fora) about 'heirarchical culture' and to some extent company training (that the company-wide emphasis was on relying on instruments rather than visual landing).

neerajb · Post by **neerajb** » 09 Jul 2013 11:32

It is obvious from the video that the pilots were too loo and they knew it too because they were pitching the nose up all the time. People on Anet are reporting that pilot called out go around 4 seconds prior to impact and pushed the throttles 1.5 seconds prior to impact and the engines responded normally. It's strange that they couldn't judge the trajectory of the plane in such clear sunny day. Their speed was abnormally low at 98 kts instead of 135 kts. Likely pilot error in this case.

Cheers....

Suraj · Post by **Suraj** » 09 Jul 2013 21:33

On the surface, the crash looks like a massive rookie error. However, even if the pilot is new to SFO or to the B777, he's still an experienced pilot who should have guessed much earlier that he was not on glideslope. I would not be surprised if further investigation reports that either the altimeter, the airspeed indicator, or both, were giving false data. One crucial bit of information seems to be that the pilots confirmed 137kt at landing, but actual airspeed was only 106kt, well below minimum landing speed or stall threshold.

chetak · Post by **chetak** » 10 Jul 2013 00:21

After Asiana 214, Examining the Intricacies and Perils of Landing a Modern Airliner

By Jason Paur
07.09.13
6:30 AM

Photo: NTSB

Much of the speculation about why Asiana Airlines flight 214 crashed-landed in San Francisco, killing two people and injuring scores more, is focusing on the pilot’s experience and the equipment used. Information released by investigators thus far raises several questions, the biggest being why the Boeing 777 slowed so dramatically in the final minute of its approach. We won’t have definitive answers for some time, but we can break down how Saturday’s approach transpired and explain exactly how a modern airliner makes it to the ground — and what could go wrong.

There were four pilots on board the 777, which is not unusual for a transoceanic flight. Typically, one pair will sleep or relax in the crew rest bunks just behind the cockpit while the other is flying. According to the National Transportation Safety Board, the pilot at the controls was a captain in training with 43 hours in a 777 but nearly 10,000 hours in other airliners, including the Boeing 747. In addition to the flight experience, the pilot, identified as Lee Kang-kook by Asiana Airlines, also would have undergone many hours of transition training in a 777 simulator.

The “approach plate” showing the information, including the glidepath in the lower right, used during an ILS approach to runway 28L at SFO.

While it might sound unusual that a pilot with just 43 hours of experience would be landing the plane, it is normal, and of course necessary for pilots to fly an airplane new to them with relatively low experience in a particular type. It was first officer Jeff Skiles’ first day in an Airbus A320 when he and Captain Sully Sullenberger performed the “Miracle on the Hudson” by successfully landing in the Hudson River in 2009.

And the captain sitting in the left seat of Flight 214 has more than 3,000 hours of experience flying 777s, and more than 12,000 hours of total experience. Crew resource management is another factor to consider, which includes the delegation of duties in the cockpit and often includes one pilot flying, while the other pilot reads out critical information including airspeed and altitude.

But under normal circumstances any pilot who has passed the exam and has a license should be able to make a visual approach and determine whether or not they are likely to land short of the runway and adjust accordingly. This will clearly be a focal point of the investigation of Asiana 214.

During a normal flight, the pilots will configure an airplane like the 777 for a stabilized approach well before landing. In a stable approach the aircraft’s configuration including the flaps, power setting, speed brakes, and landing gear are selected as necessary and appropriate during the descent. The airspeed and rate of descent are ideally stable, or at least within an acceptable range that will result in the preferred speeds during the final phase of the approach. Occasionally an air traffic controller will ask for a non-standard approach. One example is referred to a “slam dunk” approach when an aircraft might be kept at a higher than normal altitude early in the approach phase, and then perform an expedited descent to the final phase before landing. These are not unusual under visual conditions, and according to many airline pilots they are common at SFO. Such an expedited descent can lead to an approach that is not a standard stabilized approach, at least during the early phase and would require extra attention.

According to the NTSB, Asiana flight 214 was cleared for a visual approach for runway 28L. This allows the pilots to fly using only their eyes to guide them to the runway. This is a normal type of approach when the skies are clear and there are no adverse weather conditions to deal with — as was the case on Saturday, a picture-perfect day in San Francisco.

In cloudy weather when the visibility is worse, pilots can use different equipment to guide them to the airport well before they can see the runway outside the window. Today, GPS is used regularly, but a common type of approach for an airliner is an instrument landing system, or ILS. An ILS approach has two principal components, a localizer transmitter which provides a radio signal guiding the aircraft laterally, and a glide slope transmitter that provides a signal that guides the aircraft vertically. These signals can provide extremely precise guidance for an airplane, and the most advanced types allow it to touchdown on the center line of the runway, in the landing zone, with zero visibility outside the window.

The glide slope transmitter for the ILS approach on runway 28L at SFO has been out of service since June 1. This means an ILS approach would not be used for that runway if the weather was bad. There are other types of instrument approaches that can be used for 28L, including a GPS-based RNAV approach that offers nearly identical “minimums,” meaning it can be used in almost the same kind of conditions as the ILS.

Even on a day like Saturday, when the pilot is cleared for a visual approach, a pilot may use the ILS or other instrument approach as a source of guidance, but it is not required and all licensed pilots are capable of making a visual approach to landing without using the navigation instruments. Since they were cleared for a visual approach, the pilots of Asiana 214 would use other tools to guide them to the proper glide slope for runway 28L.

A satellite view of runway 28L and 28R at SFO. Image: DigitalGlobe/USGS/USDA/Google

For a visual approach there are several aides for pilots to guide them to touchdown on the runway. The first is simply basic pilot training where they learn to judge whether they are above or below a path that will take them to their intended touchdown point. The changing perspective of the runway during approach gives the pilot a chance to estimate whether or not they are high or low, indicating whether they will land long or short of their intended touchdown point. This technique is used commonly on smaller airports, including grass runways where there are no other tools available to the pilot.

At larger airports, there markings on the runway that indicate the touchdown zone as well as an aiming point. The touchdown zone markings are spaced every 500 feet at each end of a runway, while the aiming point markings are solid rectangles located 1,000 feet from the end of the runway. Based on the tire marks left behind on runway 28L in the picture above, it appears that airliners typically land between 1,000 to 2,500 feet down the 11,381-foot-long runway 28L at SFO.

An image from a 777 simulator flight done at Boeing’s flight research facility shows a high final approach to runway 19L at SFO. The four horizontal lights to the left of the runway are the PAPI lights indicating the high approach.

There are also visual indicators located to the side of the runway to help guide pilots on the proper glide slope. Runway 28L at SFO uses a precision approach path indicator (PAPI) which consists of four bright lights that can be seen up to five miles away during the day. If all four of the horizontally placed lights are white as in the image above, the aircraft is too high and will land beyond the touchdown zone unless changes are made to the approach. If one light is red, the aircraft is slightly high. If there are two red lights and two white lights, the aircraft is on the proper three-degree glide slope and will land in the touchdown zone. Three red lights means you’re slightly low, and four red lights means you’re well below the glide path and will land short of the touchdown zone. Saturday’s crash damaged the PAPI lights and they were subsequently placed on a Notice to Airmen, or NOTAM list for the airport and listed as out of service.

Because Asiana 214 was cleared for the visual approach, and there was an inoperable glide slope, under normal circumstances the pilots would use the runway markings as aiming points, and the PAPI lights to place them on the correct glide slope. It is not yet known why this system did not work and is a question the NTSB is seeking to answer.

The airplane was flying on autopilot during the initial part of the approach. This is a typical procedure for most airlines and the autopilot is treated as a third crew member by most airline pilots. With the autopilot engaged, the pilots are still responsible for adjusting things such as the flap settings as well as lowering the landing gear.

At 1,600 feet and 82 seconds before the crash, the autopilot was disengaged. Nine seconds later the airplane was at 1,400 feet and the airspeed was 170 knots (196 mph). The speed the pilots wanted to fly during the final portion of the approach is known as the “reference speed”, or Vref. Based on the weight and configuration of the 777-200ER on Saturday, the Vref speed was 137 knots.

According to the NTSB there was no discussion of any aircraft anomalies by the pilots and the engines appeared to be working normally.

At 1,000 feet and 54 seconds before impact, the airplane had slowed to 149 knots. Even though the pilots would not be using the ILS navigation information displayed in the cockpit, they would still be using other instruments displaying the their airspeed, altitude, rate of descent as well as engine information. In addition, there is normally an audible reading of the altitude as the airplane makes the approach with a voice reading out key altitudes. The NTSB says they are still reviewing the glide slope information, and hope to release the details of when the aircraft departed the proper glide slope that caused it to impact the ground short of the touchdown zone.

At 500 feet and just 34 seconds before impact, the airspeed slowed to 134 knots, three knots below the Vref speed which is clearly indicated on the speed tape — a vertical display bar showing the airplane’s airspeed on a glass display in the cockpit. There is also a visual warning on the speed tape as the airplane slows below Vref, and more visual warnings as the speed continues to decrease.

There’s been a lot of talk about “stall speed” and the Vref is not the stall speed. First, a stall is an aerodynamic situation where the wing exceeds a critical angle with reference to the oncoming air, the angle of attack. When the critical angle of attack is exceeded, the airflow begins to detach from the wing which is no longer able to generate sufficient lift to keep the airplane flying. The stall speed is the airspeed based on the weight and configuration of the airplane where the critical angle of attack would occur under normal flight conditions. Vref is an approach speed above the stall speed, giving the pilots a margin of safety during the approach.

Traveling a few knots below the Vref speed, while not ideal, is not going to cause an immediate problem. It is however an indication to a pilot that it is time to change the configuration of the airplane by either pitching the nose down or adding power — or both — to get back to the Vref speed while maintaining the proper glide slope.

According to the NTSB it doesn’t appear the necessary changes were made, and at 200 feet the airspeed had slowed to 118 knots. Eight seconds later the throttles began moving forward according to the NTSB. It is not clear if the pilots realized they needed to boost their speed and/or adjust their rate of descent, or if the automatic “wake up” mode that automatically adds more power as the stall speed is approached had engaged. In either case, one of the challenges of flying a jet-powered aircraft is that unlike a car or even a propeller airplane, there is a significant delay between the moment you apply power with the levers, and when the engines produce the thrust you are requesting. The throttles began moving forward just eight seconds before impact at 125 feet above the water and at an airspeed of just 112 knots.

At this point the 777 is approaching its stall speed and four seconds before impact the “stick shaker” can be heard according to the NTSB’s analysis of the cockpit audio recording. The airplane has a device that measures the angle of attack of the airplane and as the critical angle of a stall nears, the control yoke shakes in the pilots hands, providing the pilots a final vibrating indicator that a stall is imminent if nothing changes.

Three seconds prior to impact the airplane reached its lowest speed of 103 knots with the engines at 50 percent power and increasing, according to the NTSB. Moments later, at 1.5 seconds before impact, the NTSB says the pilot called for a “go-around”. This means the pilots wanted to abandon the approach and climb again to make another attempt. A go around in a 777 is typically executed by pushing a switch known as the TOGA (take-off, go-around) located on the throttle levers. When the switch is pushed, the airplane automatically goes to a power setting for a 2,000 foot per minute climb, and a second push provides full take off power. But again, the engines take time to “spool up” and deliver the requested thrust.

In the case of Asiana 214, the NTSB did not say whether or not the go-around function was engaged or not in the 1.5 seconds between the call for a go-around and the impact. The 777 impacted the ground at 106 knots — 122 mph — and at least several hundred feet shy of the runway touchdown zone.

Investigators in Washington D.C. are completing a more thorough examination of both the cockpit and flight data recorders. The four pilots are being also being interviewed and should be able to provide valuable information into the cause of the accident.

It deserves noting that there were a total of 307 people on board the 777, including passengers and crew. The high survival rate is a testament to the safety of modern airliners and the training of the crew. The aircraft structure is more crash-worthy than early airliner designs and the design of the passenger seats are capable of absorbing loads 16 times the force of gravity. Add in the cabin crew’s ability of evacuating the passengers from the burning jumbo jet in a short period of time, and the result is hundreds of lives saved and a surprisingly low amount of injuries and — especially — fatalities

chetak · Post by **chetak** » 10 Jul 2013 06:43

NTSB: Asiana 777 commanding pilot assumed auto-throttles were maintaining speed

Aaron Karp
Jul. 9, 2013
NTSB investigator documents Asiana Flight 214 wreckage
Courtesy, NTSB

The pilot in command of Asiana Airlines Flight 214, the Boeing 777-200ER that crashed on landing at San Francisco International Airport (SFO) July 6, told investigators that he assumed the aircraft’s auto-throttles were engaged and maintaining a speed of 137 knots as the 777 came in for a landing. The aircraft’s speed dropped to just 103 knots at the time of impact.

The commanding pilot was one of three pilots in the cockpit at the time of the crash, sitting in the right seat. He was serving as an instructor for the pilot flying the aircraft, sitting in the left seat, who was in the midst of training on the 777 after serving for eight years as an Airbus A320 captain for Asiana.

“At about 500 feet, [the commanding pilot] realized they were low,” US National Transportation Safety Board (NTSB) chairman Deborah Hersman said at a Tuesday news conference in San Francisco. “He told the [flying] pilot to pull back.”

The commanding pilot told NTSB he realized a go-around was necessary and noted the flying pilot had already pushed the throttles forward. But it was too late; the aircraft’s main landing gear was the first to impact SFO’s sea wall as the 777 came down short of runway 28L, Hersman said. The tail section then hit the sea wall. The aircraft “went into a 360 degree spin,” she added.

Debris from the crash, in which two passengers were killed, can be seen from the sea wall all the way to where the aircraft came to a stop, Hersman said. “Sections of the cabin are found very early on in the debris field,” she noted, pointing out that aircraft parts, galley materials, newspapers and magazines are scattered throughout the debris field

neerajb · Post by **neerajb** » 10 Jul 2013 20:48

Chairman Hersman's third media briefing on Asiana flight 214 crash

Cheers....

Singha · Post by **Singha** » 11 Jul 2013 08:06

she looks like a thinner steffi graf!

anyways what is auto throttle? you dial some speed and it maintains that regardless of headwind or direction ?

neerajb · Post by **neerajb** » 11 Jul 2013 09:06

Airbus's autothrust and boeing's auto throttle are pretty confusing. Can someone in know shed more light on the differneces of these two systems?

On airbuss (in this case A320), I have seen two steering wheel type rims on either side of throttles mounted vertically and they sport a checkered pattern. I have seen them rotating on their own while AP/autothrust is engaged ( I am guessing here). What is the function of those two wheels?

Cheers....

Singha · Post by **Singha** » 11 Jul 2013 21:55

Are the two levers linked together or the pilots hands are expected to grasp both and push pull them equally?
Other than turning on the ground is there any in flight use of differential engine thrust settings?

nachiket · Post by **nachiket** » 11 Jul 2013 22:11

vikrant wrote:Airbus's autothrust and boeing's auto throttle are pretty confusing. Can someone in know shed more light on the differneces of these two systems?

On airbuss (in this case A320), I have seen two steering wheel type rims on either side of throttles mounted vertically and they sport a checkered pattern. I have seen them rotating on their own while AP/autothrust is engaged ( I am guessing here). What is the function of those two wheels?

Those discs on the side are for setting the stabilizer trim and have nothing to do with the throttle AFAIK.

The difference in Boeing's and Airbus' auto-throttle is that when the autopilot changes the throttle setting in a Boeing aircraft, the throttles actually move automatically and if the pilot is tightly holding the throttle they may not move and the auto-throttle system may get overridden. In an Airbus, the physical throttle levers don't actually move and it makes no difference if the pilot is just holding them tightly. The problem is it is not immediately apparent what the throttle setting is currently unless you look at the engine status display.

This is from what I've gathered on the net. I could be mistaken though.