Avss Tenerife Accident Report

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INTRODUCTION Aviation safety is the concern of the whole world. Its importance is unanimously recognized. While air transportation is by far the safest mode of travel, as measured by the ratio between the number of accidents and that of passenger/ kilometres, It is susceptible to inherent risks of flight, the use of force, and, more dangerously, terrorist acts. From time to time, when major aviation related accidents or tragic events take place, the whole world is shaken. Consequently, aviation safety has been and will be a matter of vital importance for governments, industry, the academic community and the traveling public. It is also the raison d’être of ICAO, a global, inter-governmental organization which became a specialized agency of the United Nations in 1947. While everyone agrees that aviation safety is important, opinions vary when an attempt is made to define the term “safety”. The Oxford Dictionary defines “safety” as “freedom from danger or risks”. It also means “the state of being protected from or guarded against hurt or injury”. Clearly, if aviation must be free from any dangers or risks, it will not exist at all. Flight is inherently a risky venture, carried out in a hostile environment at great speed. The only way to assure risk-free flight is never to allow the airplane to leave the gate.

description

Tenerife accident description

Transcript of Avss Tenerife Accident Report

Page 1: Avss Tenerife Accident Report

INTRODUCTION

Aviation safety is the concern of the whole world. Its importance is unanimously

recognized. While air transportation is by far the safest mode of travel, as measured by

the ratio between the number of accidents and that of passenger/ kilometres, It is

susceptible to inherent risks of flight, the use of force, and, more dangerously, terrorist

acts. From time to time, when major aviation related accidents or tragic events take

place, the whole world is shaken. Consequently, aviation safety has been and will be a

matter of vital importance for governments, industry, the academic community and the

traveling public. It is also the raison d’être of ICAO, a global, inter-governmental

organization which became a specialized agency of the United Nations in 1947.

While everyone agrees that aviation safety is important, opinions vary when an

attempt is made to define the term “safety”. The Oxford Dictionary defines “safety” as

“freedom from danger or risks”. It also means “the state of being protected from or

guarded against hurt or injury”. Clearly, if aviation must be free from any dangers or

risks, it will not exist at all. Flight is inherently a risky venture, carried out in a hostile

environment at great speed. The only way to assure risk-free flight is never to allow the

airplane to leave the gate.

Accordingly, some commentators tend to link the concept of safety with accident

prevention. They consider “safety” as meaning “no (avoidable) accidents”, or more

realistically, “as few accidents as possible”. From a micro and operational point of view,

this definition is helpful since much of the safety concern is related to accident

prevention. From a macro and policy-oriented point of view, “accident prevention” is too

tight a straitjacket to coat the much broader policy consideration underlying the safety

issues. Aviation safety includes but is not limited to operational flight safety. The tragic

events of 11 September 2001, which constituted not only the most serious threat but also

unprecedented damage to aviation safety, have conclusively demonstrated that aviation

safety goes beyond accident prevention from a technical point of view and extends to

more profound political, strategic and legal dimensions. It includes preventive, remedial

and punitive measures. Accordingly, safety is not limited to accident prevention, but

should be considered in a broader term as risk management.

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After a period of study, the ICAO Air Navigation Commission defined “aviation

safety” as “the state of freedom from unacceptable risk of injury to persons or damage to

aircraft and property”. Risks could be at a lower or higher level. Depending on the risks

involved, the scope of the aforementioned management may range from routine

suspension of a license of an unqualified pilot to the temporary grounding of all civil

aircraft at the time of a crisis.

Sometimes, a particular safety standard is very attractive from a technical point

of view, but it may not be cost-effective or may even be economically prohibitive to

implement. In that case, a careful policy judgement is needed to determine what standard

should be imposed. Consequently, aviation safety requires a multidisciplinary approach:

technical, economic, managerial, and, obviously for the purposes of the present study,

legal

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BACKGROUND OF AN ACCIDENT

The Tenerife airport disaster was a fatal runway collision between two Boeing

747s on Sunday, March 27, 1977, at Los Rodeos Airport (now Tenerife North Airport)

on the Spanish island of Tenerife, one of the Canary. The crash killed 583 people,

making it the deadliest accident in aviation history. As a result of the complex interaction

of organizational influences, environmental preconditions, and unsafe acts leading up to

this aircraft mishap, the disaster at Tenerife has served as a textbook example for

reviewing the processes and frameworks used in aviation mishap investigations and

accident prevention.

A bomb explosion at Gran Canaria Airport, and the threat of a second bomb,

caused many aircraft to be diverted to Los Rodeos Airport. Among them

were KLM Flight 4805 and Pan Am Flight 1736 – the two aircraft involved in the

accident. At Los Rodeos Airport, air traffic controllers were forced to park many of the

airplanes on the taxiway, thereby blocking it. Further complicating the situation, while

authorities waited to reopen Gran Canaria, a dense fog developed at Tenerife, greatly

reducing visibility.

It begins when the KLM flight landed in Tenerife first and its passengers were

deplaned. The Pan Am flight landed 45 minutes later but its passengers remained on

board. The airport at Las Palmas reopened 15 minutes later. The Pan Am aircraft was

immediately ready to depart for Las Palmas but was parked behind the KLM and could

not depart until the KLM aircraft taxied for takeoff. More than two hours passed before

the KLM refueled, re-boarded the passengers, and was ready for takeoff. Clouds and fog

made visibility very poor, as low as 300 meters, so the controllers in the tower and the

crews of both aircraft were completely dependent on their radios for information on

runway positions. The tower instructed the KLM to taxi down the takeoff runway, turn

around, and wait for further instructions. The Pan Am was to follow behind the KLM on

the takeoff runway, turn off at taxiway C3, and use a parallel runway for the rest of its

taxi. After completing its turn around at the end of the runway, the KLM requested both

takeoff and air traffic control’s (ATC) clearance.

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The first officer of the KLM radioed, “The KLM 4805 is now ready for takeoff

and we are awaiting our ATC clearance.”

The tower replied with the following ATC clearance, “KLM…you are cleared to

line Papa Beacon, climb to…”

While the KLM first officer was reading back the ATC clearance to the tower,

the KLM captain released the brakes and said, “We gaan” (we go), and began the takeoff

roll.

After completing the ATC’s read back, the first officer said either, “We are now

—eh—taking off” or “We are now at takeoff.” (The tapes of transmission were not

clear.)

In a later statement, the tower controller said he understood the first officer’s

message to be, “We are at takeoff position.” The controller replied in response, “Okay,”

then paused for two seconds and said, “Stand by for takeoff, I will call you.”

Meanwhile, in the Pan Am cockpit, the captain remarked that the KLM could

possibly interpret the ATC clearance as takeoff clearance. So, immediately after the

tower said “okay” and paused, the Pan Am first officer quickly responded, “We are still

taxiing down the runway.” This Pan Am message coincided with the end of the tower ’s

instructions to the KLM to standby, which in the KLM cockpit caused a strong squeal.

Both messages were barely intelligible in the KLM cockpit. The controller then told the

Pan Am to report when clear of the runway and the Pan Am replied they would report

when clear.

In the KLM cockpit, apparently only the flight engineer heard these last two

messages leading to the following dialogue:

Engineer, “Is hij er neit af-dan?” (Is he not clear, then?)

Captain, “Wat zag je?” (What did you say?)

Engineer, “Is hij er niet af die Pan American?” (Is he not clear, that Pan

American?)

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Captain: “Jawal.” (Yes)

As a result of several misunderstandings, the KLM flight tried to take off while

the Pan Am flight was still on the runway. The resulting collision destroyed both aircraft,

killing all 248 aboard the KLM flight and 335 of 396 aboard the Pan Am flight. Sixty-

one people aboard the Pan Am flight, including the pilots and flight engineer, survived

the disaster.

As the accident occurred in Spanish territory, Spain was responsible for

investigating the accident. Investigators from the Netherlands and the United States also

participated. The investigation revealed that the primary cause of the accident was the

captain of the KLM flight taking off without clearance from Air Traffic

Control (ATC). The investigation specified that the captain did not intentionally take off

without clearance; rather he fully believed he had clearance to take off due to

misunderstandings between his flight crew and ATC. Dutch investigators placed a

greater emphasis on this than their American and Spanish counterparts, but ultimately

KLM admitted their crew was responsible for the accident, and the airline financially

compensated the victims' relatives.

Figure 1 Chronology of accident.

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FATALITIES OF THE ACCIDENT

Pan Am Flight 1736

Type : Boeing 747–121

Name : Clipper Victor

Operator : Pan American World Airways

Registration : N736PA

Flight origin : Los Angeles Int'l Airport Los Angeles, United States

Stopover : John F. Kennedy Int'l Airport New York City, United States

Destination : Gran Canaria Airport Canary Islands, Spain

Passengers : 380

Crew : 16

KLM Flight 4805

Type : Boeing 747-206B

Name : Rijn ("Rhine")

Operator : KLM Royal Dutch Airlines

Registration : PH-BUF

Flight origin : Schiphol Airport Amsterdam, Netherlands

Destination : Gran Canaria Airport Canary Islands, Spain

Passengers : 234

Crew : 14

Fatalities : 335 (326 passengers, 9 crew)

Survivors : 61

Fatalities : 248 (all)

Survivors : 0

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Total Fatalities 583 people

PHASE OF THE FLIGHT DURING THE ACCIDENT HAPPEN

Figure 2

Based on figure 2, the phased of flight of the accident happened are at phased

pre-flight/taxi and the take-off/initial climb. By following the tower's instructions, the

KLM was cleared to taxi the full length of the runway and make a 180° turn to get into

take-off position. While the KLM was back taxiing on the runway, the controller asked

the flight crew to report when it was ready to copy the ATC clearance. Because the flight

crew was performing the checklist, copying this clearance was postponed until the

aircraft was in take-off position on Runway 30.

Shortly afterward, the Pan Am was instructed to follow the KLM down the same

runway, exit it by taking the third exit on their left and then use the parallel taxiway.

Initially, the crew was unclear as to whether the controller had told them to take the first

or third exit. The crew asked for clarification and the controller responded emphatically

by replying: "The third one, sir; one, two, three; third, third one". The crew began the

taxi and proceeded to identify the unmarked taxiways using an airport diagram as they

reached them.

The crew successfully identified the first two taxiways (C-1 and C-2), but their

discussion in the cockpit never indicated that they had sighted the third taxiway (C-3),

which they had been instructed to use. There were no markings or signs to identify the

runway exits and they were in conditions of poor visibility. The Pan Am crew appeared

to remain unsure of their position on the runway until the collision, which occurred near

the intersection with the fourth taxiway (C-4).

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The angle of the third taxiway would have required the plane to perform a turn of

approximately 148°, which would lead back toward the still-crowded main apron. At the

end of C-3, the Pan Am would have to make another 148° turn in order to continue

taxiing towards the start of the runway. Taxiway C-4 would have required two 35° turns.

A study carried out by the Air Line Pilots Association after the accident concluded that

making the second 148° turn at the end of taxiway C-3 would have been "a practical

impossibility". Subsequent performance calculations and taxi tests with a Boeing 747

turning off on an intersection comparable to the C-3 at Tenerife, as part of the Dutch

investigation, indicate that in all probability the turns could have been made. The official

report from the Spanish authorities explains that the controller instructed the Pan Am

aircraft to use the third taxiway because this was the earliest exit that they could take to

reach the unobstructed section of the parallel taxiway.

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WAS THE ACCIDENT DUE TO HUMAN ERROR/ WEATHER/ DESIGN OR

WHAT? EXPLAIN

1. Weather Condition

Tenerife / Los Rodeos airport is at 633 metres (2,077 feet) above sea

level, which accounts for cloud behaviour that differs from that at most other

airports. Clouds at 600 m (2,000 ft) above ground level at the nearby coast are at

ground level at Los Rodeos / Tenerife North. Drifting clouds of different

densities cause wildly varying visibilities, from unhindered at one moment to

below the minimums the next. The collision took place in a high density cloud.

The Pan Am crew found themselves in poor and rapidly deteriorating

visibility almost as soon as they entered the runway. According to the ALPA

report, as the Pan Am aircraft taxied to the runway, the visibility was about 500

m (1,600 ft). Shortly after they turned onto the runway it decreased to less than

100 m (330 ft).

Meanwhile, the KLM was still in good visibility, but with clouds blowing

down the runway towards them. "The KLM aircraft completed its 180 degree

turn in relatively clear weather and lined up on Runway 30. The next cloud was

some 900 m (3,000 ft) down the runway and moving towards the aircraft at about

12 knots (6 meters per second)".

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2. Taxiing and Take-off Preparations

Figure 2

Based on the figure 2, by following the tower's instructions, the KLM was

cleared to taxi the full length of the runway and make a 180° turn to get into take-

off position. While the KLM was back taxiing on the runway, the controller

asked the flight crew to report when it was ready to copy the ATC clearance.

Because the flight crew was performing the checklist, copying this clearance was

postponed until the aircraft was in take-off position on Runway 30.

Shortly afterward, the Pan Am was instructed to follow the KLM down

the same runway, exit it by taking the third exit on their left and then use the

parallel taxiway. Initially, the crew was unclear as to whether the controller had

told them to take the first or third exit. The crew asked for clarification and the

controller responded emphatically by replying: "The third one, sir; one, two,

three; third, third one". The crew began the taxi and proceeded to identify the

unmarked taxiways using an airport diagram as they reached them.

The crew successfully identified the first two taxiways (C-1 and C-2), but

their discussion in the cockpit never indicated that they had sighted the third

taxiway (C-3), which they had been instructed to use.[16] There were no

markings or signs to identify the runway exits and they were in conditions of

poor visibility. The Pan Am crew appeared to remain unsure of their position on

the runway until the collision, which occurred near the intersection with the

fourth taxiway (C-4).

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The angle of the third taxiway would have required the plane to perform a

turn of approximately 148°, which would lead back toward the still-crowded

main apron. At the end of C-3, the Pan Am would have to make another 148°

turn in order to continue taxiing towards the start of the runway. Taxiway C-4

would have required two 35° turns. A study carried out by the Air Line Pilots

Association after the accident concluded that making the second 148° turn at the

end of taxiway C-3 would have been "a practical impossibility". Subsequent

performance calculations and taxi tests with a Boeing 747 turning off on an

intersection comparable to the C-3 at Tenerife, as part of the Dutch investigation,

indicate that in all probability the turns could have been made. The official report

from the Spanish authorities explains that the controller instructed the Pan Am

aircraft to use the third taxiway because this was the earliest exit that they could

take to reach the unobstructed section of the parallel taxiway.

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3. Communication Misunderstand

KLM Crew (captain, engineer, co-pilot), Tenerife Tower, Pan Am

Immediately after lining up, the KLM pilot advanced the throttles and the

aircraft started to move forward. The co-pilot advised the captain that ATC

clearance had not yet been given, and Captain Veldhuyzen van Zanten responded,

"I know that. Go ahead, ask." Meurs then radioed the tower that they were "ready

for take-off" and "waiting for our ATC clearance". The KLM crew then received

instructions which specified the route that the aircraft was to follow after take-off.

The instructions used the word "take-off," but did not include an explicit

statement that they were cleared for take-off.

Meurs read the flight clearance back to the controller, completing the

readback with the statement: "We are now at take-off." Captain Veldhuyzen van

Zanten interrupted the co-pilot's read-back with the comment, "We're going."

The controller, who could not see the runway due to the fog, initially

responded with "OK" (terminology which is nonstandard), which reinforced the

KLM captain's misinterpretation that they had take-off clearance. The controller's

response of "OK" to the co-pilot's nonstandard statement that they were "now at

take-off" was likely due to his misinterpretation that they were in take-off

position and ready to begin the roll when take-off clearance was received, but not

in the process of taking off. The controller then immediately added "stand by for

take-off, I will call you," indicating that he had not intended the clearance to be

interpreted as a take-off clearance.

A simultaneous radio call from the Pan Am crew caused mutual

interference on the radio frequency, which was audible in the KLM cockpit as a

three-second-long whistling sound (or heterodyne). This caused the KLM crew to

miss the crucial latter portion of the tower's response. The Pan Am crew's

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transmission was "We're still taxiing down the runway, the Clipper 1736!" . This

message was also blocked by the interference and inaudible to the KLM crew.

Either message, if heard in the KLM cockpit, would have alerted the crew to the

situation and given them time to abort the take-off attempt.

Due to the fog, neither crew was able to see the other plane on the runway

ahead of them. In addition, neither of the aircraft could be seen from the control

tower, and the airport was not equipped with ground radar.

After the KLM plane had started its take-off roll, the tower instructed the

Pan Am crew to "report when runway clear." The Pan Am crew replied: "OK,

we'll report when we're clear." On hearing this, the KLM flight engineer

expressed his concern about the Pan Am not being clear of the runway by asking

the pilots in his own cockpit, "Is he not clear, that Pan American?" Veldhuyzen

van Zanten emphatically replied "Oh, yes" and continued with the take-off.

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ACCIDENT MODEL USED TO EXPLAIN THE ACCIDENT

For this accident, the Swiss Cheese model would be the appropriate model that

can be used to justify the causal factors. Accident happened through a chain of events.

The chain of events are represented in the model as holed-layers. Although there are

many layers, but it also possesses weaknesses that is the holes. With the consistency of

holes existed in each and every layers, it justified why the accident happened. This

model are also widely used in risk analysis and management especially in aviation

industry

Should any obstacle blocks the hole, it will prevent an accident.

Four broad categories of Swiss Cheese Model is:

Organizational influences

Surveillance unsafe

Prerequisite for unsafe Act

Unsafe Acts

After this catastrophic event, there are numbers of lessons that has to be taken.

The standard communication and interpersonal interactions throughout the flight also has

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to be changed in order for the tragedy not to be repeated. As we progress, the Swiss

Cheese Model is a useful tool to explain this accident. With numbers of peculiar events

and the piling up of latent failures, it takes little number of active failures in the form of

unsafe acts to trigger the disaster.

Holes in the cheese

Throughout this analysis, we can see clearly on how all the holes in the cheese were

linked up and finally, creating the disaster.

1. Explosion at Gran Canaria Airport

Originally, both the Pan Am Flight 1736 and KLM Flight 4805 were

scheduled to arrive at Gran Canaria airport that day. But because there were two

bomb explosions reported at that airport, security had been compromised.

Therefore any commercial airliner was not being able to seek permission to land.

Eventually, both of the flight were forced to divert to Los Rodeos airport.

2. Size & Characteristics of Los Rodeos Airport (Tenerife)

The Los Rodeos International Airport is relatively small in size compared

to the Gran Canaria Airport. It only has one runway and one main taxiway that

only serves a small number of regional flight. Due to the nature of the airport, the

air traffic controllers (ATC) had no choice but to instruct both of the jumbos to

taxi, back-track down the runway to line up for take-off. The first aircraft, KLM

5805 was instructed to taxi down the entire runway while the Pan Am 1736 was

instructed to do the same thing as the KLM, but instead pull off into the third

taxiway (C-3).

3. Dense Fog in Tenerife

Located at 633 metres above the sea level, Los Rodeos Airport is one of the

high elevation airport in the world. At the time of the event, Los Rodeos Airport

was covered with low scattered cloud which result in dense fog. As the jumbos

began taxi down the runway, the foggy condition worsen from the visibility of

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500m to just 100m. This leads to the Pan Am 1736 failed from seeing which

taxiway they were instructed to turn at. It is worth noting that the KLM sitting

idle at the other end of the runway cannot even see the Pan Am 1736. To make it

worst, after the collision, the dense fog confused initial emergency responders

thus making them unaware of there was a second aircraft in the accident.

4. Absence of Ground Radar

The surface movement radar (SMR) has been introduced by the

International Civil Aviation Organization (ICAO) since 1950’s. By utilizing the

SMR, air traffic controllers can have a bird’s eye view on what is moving on the

airport ground. Unfortunately, being a small regional airport, Los Rodeos Airport

did not installed this technology at the time of the event. Because of that, the

dense fog completely blinded the ATC’s view from locating the jumbos and only

relied on the description that crew members of an aircraft provided through radio

transmissions along the way.

5. KLM 4805 Fully Refuels at Los Rodeos Airport

Refuelling is a normal procedure in aviation industry. But in this event, the

additional time taken to refuel the KLM aircraft delayed take-off by an additional

35 minutes, subsequently allowed the fogs to worsen thus reducing the visibility.

The extra weight from the fuel leads to the Boeing 747 to require longer runway

to reach take-off speed. Without the additional weight, KLM 4805 may have

cleared Pan Am 1736 prior to collision. Last but not least, the extra fuel directly

led to a disastrous scale of inferno when it ignited at the moment of the collision,

which resulted on low survival rate for passengers.

6. Pan Am 1736 Misses Turn

In the ATC’s instruction the Pan Am 1736 was supposed to exit the runway

via taxiway C3. The collision took place near the fourth taxiway exit that is

taxiway C4. A following analysis done by investigators shows that the exit sign

of taxiway C3 was poorly marked.

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7. Personality Traits of Key Personnel:

After the cockpit voice recorder conversations were released, Captain

Veldhuyzen van Zanten of KLM 4805 was highly criticized for his character

along this event. At first look, it seems that Capt Veldhuyzen van Zanten’s

eagerness to depart led him to increase the throttle up with the intention to take-

off without the consent of ATC.

When it happened for the first time, the KLM First Officer remind the eager

captain of no ATC clearance had been issued for take-off. In the second time

though, the KLM Flight Engineer voiced out his nervous feeling about this

action. The captain however disregard his colleague and began the take-off

sequence. Back then, Veldhuyzen van Zanten was KLM’s super star that holds

the position of chief of flight training. He is also featured on so many KLM

advertisement on their in-flight magazines showing that the company adores him.

Because of this position, the co-pilot and flight engineer was considered to feel

inferior thus making turned them into the state of inability clarify the clearance

from the ATC to take-off.

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ANALYSIS BY THE INVESTIGATORS

About 70 crash investigators from Spain, the Netherlands, the United States, and

the two airline companies were involved in the investigation.

Investigation showed that there had been misinterpretations and false

assumptions.

The investigation concluded that the fundamental cause of the accident was that

Captain Veldhuyzen van Zanten took off without take-off clearance.

The investigators suggested that the reason for his mistake might have been a

desire to leave as soon as possible in order to comply with KLM's duty-time

regulations, and before the weather deteriorated further.

Other major factors contributing to the accident were:

1. The sudden fog greatly limited visibility. The control tower and the crews

of both planes were unable to see one another.

2. Interference from simultaneous radio transmissions, with the result that it

was difficult to hear the message.

The following factors were considered contributing but not critical:

1. Use of ambiguous non-standard phrases by the KLM co-pilot ("We're at

take-off") and the Tenerife control tower ("OK").

2. The Pan Am aircraft had not exited the runway at C-3.

3. The airport was (due to rerouting from the bomb threat) forced to

accommodate a great number of large aircraft, resulting in disruption of the

normal use of taxiways.

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The Dutch authorities were reluctant to accept the Spanish report blaming the

KLM captain for the accident.

The Netherlands Department of Civil Aviation published a response that, whilst

accepting that the KLM aircraft had taken off "prematurely".

They argued that he alone should not be blamed for the "mutual

misunderstanding" that occurred between the controller and the KLM crew, and

that limitations of using radio as a means of communication should have been

given greater consideration.

In particular, the Dutch response pointed out that:

1. The crowded airport had placed additional pressure on all parties, KLM,

Pan Am, and the controller.

2. The transmission from the tower in which the controller passed KLM

their ATC clearance was ambiguous and could have been interpreted as

also giving take-off clearance.

3. The Pan Am had taxied beyond the third exit. Had the plane turned at the

third exit as instructed, the collision would not have occurred.

This was one of the first accident investigations during which the contribution of

"human factors" was studied. The human factors included:

1. The flight was one of Captain Veldhuyzen van Zanten's first after

spending six months training new pilots on a flight simulator where he

had been in charge of everything (including simulated ATC), hence

having been away from the real world of flying for an extended period.

2. The flight engineers and the first officer's apparent hesitation to challenge

Veldhuyzen van Zanten further. The official investigation suggested that

this might have been because the captain was not only senior in rank, but

also one of the most respected pilots working for the airline.

3. The reason only the flight engineer on the KLM plane reacted to the radio

transmission "OK, we'll report when we're clear" might lie in the fact that

by then he had completed his pre-flight checks, whereas his colleagues

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were experiencing an increased workload, just at the same time as the

visibility worsened.

4. Investigation concluded that the KLM crew did not realise that the

transmission "Papa Alpha one seven three six, report when runway clear"

was directed at the Pan Am because this was the first and only time the

Pan Am was referred to by that name. Before that, the Pan Am was called

"Clipper one seven three six".

The extra fuel the KLM plane took on added several factors:

1. It delayed take-off an extra 35 minutes, which gave time for the fog to

settle in

2. it added over forty tons of weight to the plane, which increased the take-

off distance and made it more difficult to clear the Pan Am when taking

off

3. It increased the size of the fire from the crash that ultimately killed

everyone on board.

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RECOMMENDATIONS

Recommendation is a suggestion or proposal as to the best course of action.

There are numerous recommendation that can be applied especially for this type of

accident. Those recommendations are:-

1. All aviation communication should be conducted precise standardized

terminology.

2. To ensure that all personnel involved in aviation are fluent in English and speak

in minimal accident a rigid standard should be applied to this matter.

3. To minimize the potential of “training syndrome” pilot instructor should fly the

majority of their flight time in regular line operations.

4. During ATC clearance the word “Take off” should never be used.

5. Every carrier airports should installed a ground radar.

6. Commercial aircraft should not taxi at any airport in visibility condition below

150 metres unless suitable taxi lighting or other visual aids and airport ground

radar are operational.

7. Means should be taken to avoid confusion of an ATC clearance with take-off

clearance. This may involve changing the name “ATC clearance” so that it is

clearly understood to be nothing more than a description of the route to be flown.

8. Whenever an aircraft is moving it is practicable to put the landing gears on.

9. For every carrier aircraft, a strobe anti-collision light should be installed and

operated whenever practicable.

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10. To confirm take off clearance in all airport a redundant means should be

provided.

11. The roles of each cockpit member should be researched by an appropriate

institution to determine optimum crew member interaction in order to minimize

the probability of human error.

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INFORMATION RETRIEVED FROM CVR AND FDR RELATED TO

CAUSED OF THE ACCIDENT

There are several incident that have been identified based on the Cockpit Voice

Recorder (CVR) and Flight Data Recorder (FDR) founding

1. According to the CVR it shows that the KLM Pilot was convinced that he had

been cleared for take-off, however the Tenerife control tower was considering

that the KLM 747 was stationary at the end of the runway and awaiting for the

take-off clearance. It also appeared that the KLM’s co-pilot was not as certain

about take-off clearance as the captain.

2. During that time also, the recorded CVR suggested that during the fatal

accident the Spanish control tower crew had been listening to a football match

on the radio and obviously they have been distracted.

3. Stand by for take-off, I will call you"...but unfortunately that transmission was

not heard clearly as two of the aircraft attempted to transmit at the same time.

4. The tower controller, in no way alarmed, has in his routine, not requested a

confirmation of his order to KLM: "Stand by for take-off".

5. The crew also faced some difficulties in term of hearing for instruction as the

background conversation in the control tower too loud.

6. The last two messages were radioed simultaneously and were therefore heard

as a long four-second high-pitched sound

Page 24: Avss Tenerife Accident Report

CONCLUSION

Trough out the event that lead to the tragic accident, it is evident that language

barriers including accent and idiomatic usage, degraded and disturb information

transfer.

The KLM captain was under great stress due to concern about the legal aspects of

the Dutch duty time limits and worsening weather condition.

The Pan Am captain already expressed a desire to hold clear of the runway,

unfortunately the controller did not receive this information.

The accident also occur due to both crews had difficulty understanding taxi

instructions, particularly those of the ground controller.

The training syndrome may have influenced the KLM’S captain decision to make

an early conclusion that he was cleared to take-off.

The Pan Am crew passed the third left taxiway in poor visibility while

concentrating on the ATC clearance being given to KLM. Due to their airplane

geometry, they do not believe this to be their assigned exit.

The controller did not obtain or received an acknowledgement from KLM behalf

to his order to “stand by for take-off”

Page 25: Avss Tenerife Accident Report

REFERENCES

1. http://en.wikipedia.org/wiki/Aviation_safety#Air_Safety_Investigators

2. http://www.nj.gov/transportation/airwater/aviation/safety.shtm

3. http://www.1001crash.com/index-page-tenerife-lg-2-numpage-6.html

4. http://en.wikipedia.org/wiki/Tenerife_airport_disaster

5. journal : Human Factor Report on Tenerife Accident, Alpa Study, 1977

6. http://en.wikipedia.org/wiki/Tenerife_airport_disaster

7. project-tenerife.com/engels/PDF/alpa.pdf

8. http://en.wikipedia.org/wiki/Tenerife_airport_disaster

9. http://www.tiptoptens.com/2013/11/25/top-10-worst-aviation-accidents/