CHAPTER ONE
INTRODUCTION1
.1. BACKGROUND TO THE STUDYAviation probably more than any other mode of transportation is tremendouslyaffected by weather. Every phase of flight operation that is from the take off to thelanding and also when aircraft is in-flight hasthe potential to be influenced byweather (Kulesa, e2013). Aircraft travels through the atmosphere. The atmosphere varies vertically andhorizontally in pressure, temperature, density and atmospheric humidity. Itcontains quantity of water vapour, which when condensed produce a gaseous fogand continues like that to cloud, sleet, hail and precipitation all which affectvisibility (Oliver, 1997). Safety and efficiency of air traffic may be affected byweather phenomenon such as reduced visibility, turbulence, wind shear,thunderstorm particularly at the terminals of an airport, results in delays, diversion,cancellation of flight and reduced Airport capacity as well as accident (Oliver,1997).“Flight operations” is such a generalized term which encompasses many things inthe aviation operations, and that definition given to this term is based on Airlines ata local station of operation. This deals with flight and aircraft dispatch, flight crew1
and flight watch. Flight operations refer to the agents who perform weight andbalance functions for flight transiting their city for many airlines, at a local station.However, it is most acceptably defined, as the central decision-making center forthe airline that handles flight (Civil Aviation Forum, 2001 and 2005). The aircraftflight section constitutes three important phases of flying which are; take off, inflight and landing. Of these, landing has been observed to be the most difficultphase of flight operations, followed by takeoffs. Studies have shown that inaviation, 80% of all aviation accident occur shortly before, after or during takeoffor landing, and often described as resulting from “human error”. For example, theinvestigation into the crashes of Bellview and Sosoliso airlines in 2005 and ADCairline in 2006 in Nigeria were reported to occur between takeoff and landing andcaused by wind shear (variation in local wind speed and direction) however,induced by human error (All Africa Global Media, 2005 and Ayigbe, 2006). Thisresearch work is focused on this aircraft aspect of the flight operation.Visibility is one of the major climatic element, which affects all forms of trafficfrom road to aviation. It is the most obvious weather parameter that affects aircraftoperations (Hughes, 1982).Weather continues to play a significant role in numberof aviation accidents and incidents. While National Transportation Safety Board(NTSB) reports most commonly find human error to be the direct accidents caused,2
weather is a primary contributing factor in 23 percent of all aviation accidents(Kenneth and Libbrecht, 2001). There are many definition of visibility by various authors ( Aremu,2014; Ayode,1998; Dick, 1990 and others). All these definitions are saying the same thing.According to Aremu (2014), visibility is the greatest horizontal distance at which asuitable object can be seen and recognized with the unaided eye. The wordhorizontal is very important in that there may be mist or fog in a small nearbyvalley which may block the observers view. Visibility is measured by references toobjects or lights whose distance from the observation is known (Seinfeld et al,2006).Visibility has different names based on distances of occurrence in meteorology.Aremu (2014) classifies the types as fog which is less than 1km and mist which isbetween 1-2km.According to Seinfeld et al (2006), Fog and mist are generallyassumed to be composed principally of water droplets. Haze and smoke can be ofsmaller particle size.Visibility is very important for the pilot controlling an aircraft on flight conditionsclose to the ground particularly when landing or take off. The natural view of thepilot is dependent on various meteorological conditions close to the groundparticularly when landing or take off. In addition, the natural view of the pilot is3
dependent on various meteorological conditions such as darkness, dust, fog andrainfall which is the major causes of flight cancellations, diversions, delay orevenaccidents (Middleton, 1995). Low visibility can be caused by different weatherparameters; these are rainfall, thunderstorms, fog, and thick-dust haze. Liquidvisibility and fog account for most low visibility in Murtala MuhammadInternational Airport, while thick dust haze can restrict visibility and making itdifficult for landing and take – off of extremely danger.1.2STATEMENT OF THE RESEARCH PROBLEM It was reported by Ayigbe (2007) that the civil aviation practice in Nigeria hascome to the front burners in recent years because of the fear to fly as a result of thecountless plane crashes thathad drummed up public debate on the safety of livesand property. The crashes of ADC, Sosoliso, Dornier 288 (military), Bellviewaircrafts among others has safely placed Nigeria as one country with worst safetyrecord in the preceding years, and this has resulted in Nigeria been ranked numberfour (4) in the world coming after Congo, Uganda and Tanzania in air trafficdisaster. One of the reasons given by the then Minister of Aviation to beresponsible for the rampant accidents and incidents was that reports from flightoperators, especially Pilots indicated that weather reports were highly unreliable4
for safe navigation. Therefore, the Minister called on the Nigerian MeteorologicalAgency (NIMET) to improve in the year 2007.The problem being envisaged in finding solutions to the rampant air disaster inNigerian airspace by the aviation authority is the negligence in addressing theweather factors identified among the causative factors. This is because when airdisasters occur blames are being apportioned to the human and the economicfactors with little or nothing been said about the weather (natural) factors, such aswind shear, visibility, heavy rainfall, crosswind (strong wind) and over flooding.For instance, reports by Shadare (2005) shows that on 11 June 2005, an EAS planeovershot its runway by 40 meters in Jos airport before being stuck in mud due toinclement (severe) weather. Day after this, Chanchangi airliner, B727 similarlyovershot the runway by about 100 meters before been stopped by a drainagechannel in Lagos airport due to over flooding, as a result of the day’s rainfallwhich rendered the plane brakes ineffective. In addition, an EAS plane hoveredover the airport for more than two hours before landing due to flooding from heavyrains. Instead of looking at the real cause of the accidents, the then Minister ofAviation suspended the Pilots of the two planes. In addition, the recommendationsgiven to address the situation were the maintenance of aircrafts, routine check ofthe planes, pilot’s exposure to more training and refresher courses and lighteningof the runway without looking into the real cause of theaccidents. Based on these
