Monday, December 2, 2013

Impact of Personal Wellness and Acceleration forces in aviation

The generally accepted definition of Personal wellness is to stay in good condition physically, mentally, and spiritually, especially through healthy choices in those areas and having a balanced state of these parts of the psyche. Personal wellness plays a pivotal role in efficient working for any professional. But its importance is significantly higher in the case of aviators because hisher job is responsible for transporting myriad passengers. (February 15, 2010, earthzense)

There have been many cases where personal wellness has been sacrificed by aviators leading to catastrophic consequences. The pilots have been often found flying in an inebriated state. The alcohol in their body slows their reflexes. As an old saying in aviation goes Dont let your plane take to place where your mind has not reached 5 minutes ago. The airlines who fail to penalize the pilots who fly in drunken state are welcoming disaster. Another area of neglect in the case of personal wellness is fatigue. The fatigue takes a toll on the pilots as it drastically drops the alertness level and subsequently the response time. Time and again it has been witnessed that the failure to provide sufficient rest to the pilots has affected their job. The stress tends grow even more in long haul flights where the pilots go through various time zones. The tremendous physical pressure adversely affects their mental strength to handle any other arduous situation.

An example of fatigue as a probable cause of a US commercial aircraft accident occurred on August 18th, 1993 in Guantanamo Bay, Cuba involving a DC-8. Impact forces and post-accident fire destroyed the airplane, and the three flight crewmembers sustained serious injuries. Visual meteorological conditions prevailed, and an instrument flight rules plan had been filed. The following is the NTSB summary report
Probable Cause THE IMPAIRED JUDGEMENT, DECISION-MAKING, AND FLYING ABILITIES OF THE CAPTAIN AND FLIGHTCREW DUE TO THE EFFECTS OF FATIGUE THE CAPTAINS FAILURE TO PROPERLY ASSESS THE CONDITIONS FOR LANDING AND MAINTAINING VIGILANT SITUATIONAL AWARENESS OF THE AIRPLANE WHILE MANEUVERING ONTO FINAL APPROACH HIS FAILURE TO PREVENT THE LOSS OF AIRSPEED AND AVOID A STALL WHILE IN THE STEEP BANK TURN AND HIS FAILURE TO EXECUTE IMMEDIATE ACTION TO RECOVER FROM A STALL. ADDITIONAL FACTORS CONTRIBUTING TO THE CAUSE WERE THE INADEQUACY OF THE FLIGHT AND DUTY TIME REGULATIONS APPLIED TO 14 CFR, PART 121, SUPPLEMENTAL AIR CARRIER, INTERNATIONAL OPERATIONS, AND THE CIRCUMSTANCES THAT RESULTED IN THE EXTENDED FLIGHTDUTY HOURS AND FATIGUE OF THE FLIGHTCREW MEMBERS. ALSO CONTRIBUTING WERE THE INADEQUATE CREW RESOURCE MANAGEMENT TRAINING AND THE INADEQUATE TRAINING AND GUIDANCE BY THE AIRLINE, TO THE FLIGHTCREW FOR OPERATIONS AT SPECIAL AIRPORTS, SUCH AS GUANTANAMO BAY AND THE NAVYS FAILURE TO PROVIDE A SYSTEM THAT WOULD ASSURE THAT THE LOCAL TOWER CONTROLLER WAS AWARE OF THE INOPERATIVE STROBE LIGHT SO AS TO PROVIDE THE FLIGHTCREW WITH SUCH INFORMATION. (NTSB REPORT AAR-9404, ADOPTED 51094)

Another reason that has cropped up over the years that lead to severe accidents is the acceleration forces. Whenever a plane is caught in turbulence or subjected to any unforeseen circumstances a lot of pressure is exerted on the structure of the plane as well the passengers inside it.

Acceleration Forces The force of gravity on earth causes a constant acceleration of 32 feet-per-second squared. An object in freefall will accelerate at an ever-increasing speed toward earth until it impacts the earth or reaches terminal velocitythe point at which the force of aerodynamic drag acting on the object overcomes the force of acceleration induced by gravity. Acceleration is described in units of the force called Gs. A pilot in a steep turn may experience forces of acceleration equivalent to many times the force of gravity. As an aircraft enters into a high-speed, coordinated turn or begins the pullout from a steep dive, the pilot experiences GHz. (Definition of Wellness, February 16, 2010)

The acceleration forces affect the heart and cardio vascular system. These organs face tremendous amount of pressure and in rarest of rare cases have met with complete failure. Usually when the pilot or passenger face these acceleration forces then the blood flow becomes irregular as a large volume of blood moves towards the brain. The brain does not receive sufficient amount of oxygen. As a result the first sign of G forces acting on your body makes human body drowsy and feeble. Eventually the human body relinquishes to the pressure exerted and faints.

Although combat pilots are most susceptible to experience G forces but it has been seen that in a few air crashes commercial Pilots and passengers have fallen prey to G forces. One of the incident in which the pilots and passengers faced grave danger of dying was in the year 1985 when a China airlines Boeing 747 flight 006 underwent a rapid dive because of a failure of one engine. 

The airplane was subjected to tremendous stress because of the crew error to start the engine. The plane started losing altitude from 30,000Ft gradually but the moment the auto pilot was disengaged the plane lost almost 20,000 in matter of few minutes. The picture below illustrates the harrowing experience that the passengers had to undergo in those few seconds.

There were two injuries. One was a fracture and laceration of a foot the other acute back strain requiring two days of hospitalization. The aircraft was significantly damaged by the aerodynamic forces. The wings were permanently bent upwards by two inches, the inboard main landing gear lost two actuator doors, and the two inboard main gear struts were left dangling. (China Airlines 006, February 15, 2010)

But this accident once again also points out to our primary problem of pilot fatigue. The report also highlights the fact that pilots made that serious error because of the fatigue and stress related job. The Pilots failed to respond in time because they were tired both physically and mentally.

This leaves us with very little options but to accept the fact that we cannot ignore pilot fatigue. Although constant efforts have been made to negotiate with pilot fatigue yet the main grouse of pilots is their inability to sleep.

Thus I would strongly recommend that proper measure have to be taken to make sure that a Pilot is kept under good health at all times. She should not be subjected to working beyond his stipulated time period as this would be like setting up the platform for carnage. It is of prime importance that Pilots undergo a breath analyzer test to make sure that there are no traces of alcohol in their blood. Commit to making personal wellness a precondition of flying (for example, by using the IM SAFE checklist before each flight). Know your personal susceptibility to hypoxia, carry supplemental oxygen on flights where its use may benefit you or your passengers and establish oxygen personal minimumse.g., daytime above 8,000 ft. MSL  night time above 5,000 ft. MSL. The use of Yoga meditation to stress your self is also highly recommended before boarding any flight. (Aviators model code of conduct, February 16, 2010)

I would like to strongly recommend that Pilots should also be trained on similar platforms as that of the combat pilots. This will expose them to G forces and help them negotiate with them a bit better. Also this will give an opportunity for the pilots to deal with any unforeseen situation in a more comprehensive way. It is of critical importance that a Pilot realizes that she is flying the plane and not the auto pilot. Overdependence on technology can prove to be costly as there is no room for error in aviation.

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