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How safe is flying ?
Air travel is very safe. Yet many people find it difficult to come to term with this statement. They do not believe that crossing a road, climbing the staircase or having a shower at home is more risky than a journey by air in an established Airline. Fear of the unknown is one of the cause to make a person believe that airplane is not as safe as a car on the ground. Yes, flying was very unsafe in the beginning when air travels were at its infancy. Today, modern technology has made the airplane very reliable.
Flying in the early years
When I first started flying, airplanes were very basic. How safe was flying was basically dependant on the skill of the pilots and the management of the Airline. As the saying goes, to err is human. But one cannot afford to make an error where flying is concerned because lives are affected. Hence, human error is the last link in making flying safer. Fortunately, aircraft manufacturers have build in many safety and warning systems to compensate for the possible human errors of pilots.
Every individual is born differently. Some are born with the innate talent of handling the aircraft very well whilst others are not so. Hence, to be qualified as a pilot, one must demonstrate at least a ability to fly safely. Unlike driving a car, a pilot cannot afford to make a critical mistake in the air for to do so would most likely be his last error.
In the past, aircraft were designed with less safety backups and air accidents were often fatal. One example involved a wide-body airliner in the US, which had a minor problem with landing gears indication inside the cockpit. The crew was trying to determine whether the landing gears were physically down since one of the lights was faulty. It was at night and all of them were deeply engrossed with trying to fix a light bulb without monitoring that the autopilot was not flying the aircraft. It was in fact descending. As the aircraft was quite low, the slow descent of the airplane was not apparent and it eventually crashed, killing all on board.
Today, modern aircraft have been installed with many safety features and the above accident should not have happened if some of the safety warning systems were in that aircraft.
Crashing into Terrain?
The Boeing 777 is one of the latest and most modern airplanes in the world today. It has some of the safest features, which would virtually eliminate any uncontrolled flight into terrain. The system involved is known as the Enhanced Ground Proximity Warning System or EGPWS.
The EGPWS is capable of providing at least 9 warnings to the pilot so that remedial actions can be taken to prevent any event from developing into something disastrous. This can save a lot of lives, especially to a pilot who may have the misfortune of not being particularly alert on that day. Pilots are human and they can make mistakes. The warnings come in the form of aural as well as visual messages. Therefore, when a mistake will eventually develop into something dangerous, the warnings against such an event can certainly save the day!
Modern aircraft today fly at a very high speed. At the cruising level, the aircraft flies at about 9 miles a minute (550 mph) or about 800 feet a second. During the landing phase, the speed is around 170 mph or about 250 feet a second. Thus, even a few seconds delay in recognizing a potential mistake can be very costly. With the EGPWS installed, when a fatigued pilot (he should not be flying!) is slow in recognizing that his aircraft is encountering a high descent rate into terrain, he would be reminded with an aural alert, " Sink Rate!" from the computer informing him that he should do something to correct the excessive sink rate.
What happened if the tired pilot did nothing? At about 50 seconds before crashing, another warning, "Caution, Terrain!” would come through the overhead speaker warning the pilot to act, terrain is ahead! If no action is taken by about 25 seconds to impact with the terrain or ground, another final warning "Terrain, Terrain, Pull Up!" would be issued. The tired pilot must wake up now and pull up the flight controls to avoid the crash into terrain!
Landing Gears, Flaps and Over-Banking reminder
Amongst the other warnings, the EGPWS also alert the pilot if he forgets to select the landing gears or flaps when he is about to make a landing.
Many aircraft have crashed because the pilot was disorientated in bad weather. Disorientation arises when a pilot does not know if he was flying level or inverted. This is mainly due to loss of visual reference to the horizon because the pilot accidentally flew into clouds and he was not trained to fly under instruments. John Kennedy Junior was probably disorientated before he crashed into the sea.
What is the most likely cause of disorientation? In most cases, the pilot was over banking (lifting one of the wings in order to turn) his aircraft without realizing it. He was not aware he was turning because of no visual reference to the horizon or he was too engrossed with other emergencies. An over-banked aircraft will develop into a spiral dive. If not handled correctly, the aircraft would crash. The EGPWS has an alert to warn the pilot when the aircraft is over-banking excessively.
Avoiding Wind Shear
Many years back, a Boeing 727 crashed before landing in an US airport due to wind shear. Could that accident be averted? Yes, if only the EGPWS was developed then! In the Boeing 777 today, if wind shear is encountered on the approach to land, there would be a visual and aural warnings to the pilot. Firstly, the pilot would be notified to look at his radar display when wind shear is predicted 3 miles ahead. When the airplane is 1.5 miles to the predicted wind-shear and if the pilot did nothing, he would be told by the computer in the form of a aural warning to take action by aborting the landing and go around!
These are some of the major warnings that are available in the EGPWS and they do certainly save lives. Today, as more aircraft are equipped with this system, flying will become safer. It helps the pilots to detect errors that were not available to aircraft in the past.
How safe is flying on the Boeing 777?
Flying in the Boeing 777 is very safe as the aircraft is well maintained. The airlines, aircraft manufacturers and government regulators jointly worked out detailed, scheduled maintenance programs designed to avoid and detect any problems before they become serious.
Flight crews and on-board computer systems monitor aircraft performance for any problems, and those problems that pose a safety threat are corrected before further flights. Airplane makers anticipated potential equipment failures when they designed the Boeing 777 and have built in layers of redundant, back up safety features for all key airplane systems.
Even with one engine operating, the Boeing 777 is capable of flying for at least three hours without any problems. In fact, an United Airlines Boeing 777 recently flew on one engine for three hours and twelve minutes. It was flying from Auckland to San Francisco when it experienced an engine problem. The Captain had to shut down one engine and diverted to Hawaii. It landed safely without any incident.
The Boeing 777 is also the first aircraft to be completely designed by computers from the start. It is the most thoroughly tested airplane in history. For instance, the fan blade of the huge engine was deliberately failed during the trial and it continued to run without any stability problems. The head of the Federal Aviation Administration, David R Hinson was quoted as saying, "The Boeing 777 is absolutely safe ..."
Of course, the safety of air travel cannot be said to be 100 per cent absolute. A walk through the park, to the school or even to work has its inherent risks!
Poor little birds in the 'chicken gun' test!
Recently I spotted this in the Reader's Digest "Facts of Life". Its researchers have confirmed that, before any new model of commercial aircraft that is allowed into the air, its manufacturer is required to demonstrate the plane's ability to withstand bird strikes by putting it through the "chicken gun" test.
According to Steve Pettigrew of BAE Systems - maker of passenger jet, dead birds or fake gelatin birds are fired at various parts of the plane, such as engines and windscreens, through a large cannon and their impact is filmed on high speed cameras.
Planes that sustained damage that could endanger a flight, such as cracked window or engine failure, have to be redesigned.
A question from an air traveler on the safety of flying.
Dear Sir,
Your Website stated that even with one engine, the airplane could still be controlled to land safely. On the Airbus 300 crash reported in the newspaper today, it quoted that both engines failed. Two minutes after take-off, there was a blast and an engine fell off first! How is this possible?
Then there was speculation about problems on the tail fin and cross wiring. Is it still safe? Is it a sabotage?
I thought there was always a thorough check prior to each take-off or landing. Please explain for our benefit, since my daughter is contemplating another trip to the US at the end of November (by Lufthansa?)
I know it may be a bit silly to ask again, how safe is flying now?
Regards, Dr Lim Keng Huat, Malaysia
Hi Dr Lim, I know the Airbus 300 crash has frightened many air travelers in the wake of the September 11th incidents. The cause of the crash is probably not due to terrorist sabotage but likely to be mechanical in nature. Latest speculation stated that a Japan Airlines Boeing 747 took off 1 minute and 45 seconds ahead (normally there should be a 2 minutes separation) of the Airbus 300 and had created some wake turbulences trailing the aircraft. It was recorded in the voice recorder when the Captain mentioned this fact to his copilot.
According to the Cockpit Voice Recorder, (CVR) there were two abnormal rattling sounds during the take off phase and the Captain did mention about “wake turbulence” encounter followed by the copilot “full power!”, then silence after 144 seconds.
This wake turbulence may have caused the vertical stabilizer or the tail fin to rip off if there is an existing defect in the joints. Alternatively, this or an engine separation may have caused the hydraulic system to loose all the hydraulic pressures with a consequence loss of flight controls. If there are no hydraulics or if the flight controls are damaged, it is just like trying to drive a car without the steering wheel. All these are speculations only. It is still not very clear as to the exact cause of the accident yet. So I can’t answer your question positively as to whether it is possible for the engines or the tail fin to fall off, or whether any cross wiring has anything to do with the accident.
If it were a straightforward engine failure without any damage to the flight controls, then it would be no problem landing with the remaining engine (see ‘flying on one engine'). We practice this all the time in our simulator and are tested every six months to handle such an emergency.
There is always a check on all flight controls and the engines indications prior to every take-off. They must be operating normally before the brakes are released for the commencement of the take off run.
It is still safe to fly. It does not mean that if you witness a train, coach or car accident, you would not travel on them again. From statistics, taking a shower or climbing the stairs at home is 10 times more dangerous than flying. Further, driving in your car is 21 times more dangerous. Of course, very few people are convinced with statistics if they have a fear of flying. In fact, one in three air travelers have a fear of flying mainly because of the great publicity generated by the medias. Flying phobia is usually caused by scary tales of previous accidents heard in news, ignorance of the flying statistics and lack of knowledge about flying.
Remember that everything we do in life has a certain amount of risk involved. Air travel is just another risk but it happens to be a smaller risk than almost anything we do in a day. Think about this. Would anyone believe that it was dangerous working in an office inside the Twin Towers in New York where the hijacked aircraft had crashed through? Risk is everywhere if we start to worry about it.
So I would not worry about your daughter flying to Washington again or anywhere else provided you fly in a large air carrier. Lufthansa is okay because it is ranked unofficially as the second safest airline in Europe.
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