Effects of Weather on Aircraft Accidents

Effects of Weather on Aircraft AccidentsEFFECTS OF profile ON AIRCRAFT MISHAPS IN NIGERIAEfe, S. I.Geography and Regional Planning plane sectionDelta give tongue to University, Abraka.ABSTRACTThis paper is an assessment of the make of conditions on aircraft mishaps in Nigeria. This was investigated with the aid of entropy collected from the Meteorological Service Office, Oshodi and the use of questionnaire. The data were analyzed with the aid of mean and multiple regression models. Results suggest that paltry profile (less than l000m) have a signifi dissolvet solvent on aircraft mishaps in Nigeria, other casual factors of aircraft. Old time of the aircraft, lack of safe come equipment amongst others factors of aircraft mishaps.INTRODUCTION on that point have been several cases of air transportation problems c totallyable to forgetful air power last at both(prenominal) inter home(a) and national airports worldwide. For example, in U.S.A. the weather is responsible for almost 33 percent of all airwave casualtys part th to a depress placestorms ar the commonest cause of flight delays (26 percent). Also, unfavourable moves and wind shear atomic amount 18 responsible for 19 percent of flight h emeritus-ups (Hayward and Oguntoyinbo, 1987). that Critchfield (1966) and Smith (1975) have noted the effects of low-down profile on flight operation. For instance. Smith (1975) opined that despite the increasing sophistication of automatic arrive equipment, poor visibility from fog and low cloud ceilings is probably the major impediment to air operation through give away the world. In Nigeria, thither has been a series of air travel disasters link up to poor weather. But the lather aviation fatality occurred in November 1973, when 183 people died in an air crash at Kano airport during the land approaches of a pilgrim flight from Jeddah as a dull spread out cloud persisted. Also Nigeria airways, suspended its flights for one week in Janu ary 1983, due to widespread stud shock, and was describe to have lost about 15 million U.S. dollars as a force (Adefolalu, 1984). Studies in this part have been neglected over the years, rather there argon concentrations of studies on Harmattan form haze as actualisen in the works of Biglestone (1958), Burns (1961), Ireland (1962), Samray (1974), Adefolalu (1968 and 1984) and skinny and Bokop (1996). raze the study by Adefolalu (1984) which appeared more recent in Nigeria yet foc apply on the Bioclimatological aspect of Harmattan dust haze in Nigeria to the neglects of the effects of visibility on flight operations in Nigeria,. In fact, while vagaries of poor visibility on flight operation in Nigeria keep unabated, as spiritedlighted in the Nigerian Guardian November 1996, December 1998 and the Comet February 2000. There are a dwindling number of studies in this area. The reason is not at sea with the paucity of visibility data as well as myopic records of flight cer ebrovascular happenings, delays and drive outcellations in most Nigerian airports and Meteorological run departments. Even when available, exorbitant fees for their purchase scare researchers away. Thus, there is dearth of randomness in this aspect of climatology. This study is therefore carried out in Nigeria that is located at the intersection of latitude 4N and 14N, and between longitude 3E and 15E. It is characterised with wet and ironical term. However, in the coastal blast of Nigeria, wet season spans for 11 12 months.OBJECTIVES OF THE STUDYThis study is design at assessing the effects of visibility on aircraft mishaps and identifying other factors that causes aircraft mishaps in Nigeria and inspire ways of reducing aircraft mishaps in Nigeria.CONCEPT AND METHODOLOGYThe study is ground on the concept of visibility. Visibility is the highest distance an individual whoremaster see with an unassisted Hayward and (Oguntoynibo, 1987). However, in the context of the airc raft operation, it is the highest distant a fly can see on board (airborne) when taking off with the aid of an unaided eye. Visibility is said to be poor to aircraft operation, when it 100 metres and below (Efe, 1997). There are probably two main source areas for dust harmattan haze that precipitated in poor visibility in West Africa and Nigeria in particular. cardinal is the plains between Bilma and Fays Largeau in Niger and Chad, where fine dust particles are fed to the area by seasonal streams from the Tibesti upland replenishing the dust that is stripped from the surface by the winds. The sec originates west of the Ahaggar massif, Tonezrouft in Algeria. From the former source is derived the haze that may extend across Nigeria (Hayward and Oguntoyinbo, 1987). It r distributivelyes the Nigerian border about 24 hours later leaving the Fays Largeau source Region (Burns, 1961).Reduction of horizontal visibility forever marks the onset of a spell, which lasts up to 3 5 years ( Adebayo, 1980). But some spells may persist for up to 10 days, when the adduction of dust is from a thread rather than a point source. In such(prenominal) a situation, clearance of the haze may be delayed to an end that the arrival of another dust spell is not obvious. Persistence of dust haze for more than two weeks may be classified as due to only one spell whereas it could have been due to lapping spells. This pattern of particular is more conspicuous in the southern limits of the dust front which according to Adefolalu (1968), is a feature of Harmattan dust to the South of the Inter-Tropical Discontinuity (ITD). The in-flight posting on four trips between Kano and Lagos made by Adefolalu showed that the dust work is shallower but thicker in the extreme north (where visibility is poorer) and coastal separate of Nigeria. But higher to the south of the surface ITD where dynamic instability associated with the monsoon money box (Adefolalu, 1983), at about the 900mb direct lea ds to rising motion which help to distribute the dust within a deeper layers. everyplace the greater part of Nigeria, however, especially north of the forest zone, the prevalence of mist, most noticeably in the prohibitionist season, cannot be explained with have-to doe withence to atmospherical moisture. In fact, it is more accurate to refer to haze rather than mist, the former term universe used to discover visibility impaired by presence of solid aerosols, not liquid. In West Africa, particularly during the pre-rains diaphragm, such aerosols may be contributed by furnish fire (Crozat et al, 1978), but by far the greater proportion of atmospheric pollutants is dust from the north, associated with the harmattan. The influence of this dust-laden north easterly airflow, r each(prenominal)es even the Guinea beach in the period December to February.The data used for this study were extracted from the register of the Accident Unit of Murtala Mohammed Airport, Ikeja, Lagos, (19 87 1998) and the use of questionnaire. For this data collection, 1000 metres visibility speeding limit is used as visibility induce for aircraft operation, the reason being that visibility higher than 1000 metres though affect aircraft operation, but its effect will not bring the desired delays, cancellation and accidents of aircraft in Nigeria. In Nigeria, there are a total of 14 airports, out of which the Murtala Mohammed Airport Ikeja make the Central collating centre of aircraft accidents, delay and cancellation. This gave the impetus for the pickaxe of the Ikeja Airport. opposite reasons for the choice of Ikeja airport, and the years 1987 1998 include reliability, consistency continuity of records and long range of data. For each year, the total daily, monthly and annual aircraft accident as well as those accidents that are weather related was scrutinized. The seasonal occurrence of aircraft accidents was adopted by dividing the months of the year into Wet (April-Septembe r) and Dry (October March) seasons.A total of 14 questionnaires were administered to the 14 accident units of the 14 major airports in Nigeria. This was done to elicit information responses on the major causes of aircraft mishaps in Nigeria. One questionnaire each was therefore, posted to the 14 airports and same number was filled, returned and used for the study.The multiple regression analysis is used to determine the effects of poor visibility on aircraft mishaps, while line graph was used to depict the seasonal pattern of aircraft accidents in Nigeria. treatment OF RESULTSThe result of aircraft accidents from 1987 1998 are presented and discussed below.From the table above, a total of 89 cases of aircraft accidents were reported, out of which 45 were weather related and the total number of casualties were 498. During the period under investigation, the year 1988 enter the highest rate of aircraft accidents of 14 cases, out of which 9 were caused by poor visibility. This was f ollowed by 1992 (10 cases), 1990, 1991 and 1995 (9 cases each), 1998. (8 cases), 1989 (7 cases) and the lowest rates of accidents occurred in 1993 and 1977 (3 cases), poor visibility was the major causes of 2 cases in the year 1997. Over these years, poor visibility was known to be an inducement of these accidents as shown in the weather related column of table 1. In 1988, the 9 weather related cases of accident out of the 14 total cases reported. occurred during the dry season when the hamattan dust haze was said to be highest in the country. Fog, mist, rain, and strong winds are other weather factors that have contributed to the accident rates over the years. Most especially those that happened during the months of April September, are as a result of foggy and misty weather that could sometimes reduce the visibility to 50m in the morning. For instance as a result of foggy and misty weather on June 26th and 11 July 1991 the Nigeria flight path Airbus 310 and Ashaka Cement Cessna Citation 550 crash landed at Murtala Mohammed Airport Lagos, and union Al 1. Airport in Bauchi respectively. Causalities were said to be 4 and 261 respectively. This was the worst aviation mishap during the period of this study.It was gathered that 5 airports (Sokoto, Kano, Kaduna, Bauc1, and Lagos) have reported cases of visibility related accidents. This gives 36% percent of the 14 Nigerian airports. Sokoto enter the highest accident records of 28 cases, while Lagos with 8 cases, recorded the lowest accidents during the period of study.Looking at the casualty trends, 1991 recorded the highest (267), this was followed by 1996 (168), 1995 (26), 1988 (14), 1993 (9) 1997 (7), 1998 (5), and 1989and 1992 (1 each) being the lowest. However, no casualty was recorded in 1990 and 1993 though there were reported cases of 9 and 3 aircraft accidents. The ADC B727 airline that crashed into the Ejinrim water on November 6, 1996, claiming the lives of 146 passengers and crew recorded the seco nd worst casualties during this period. Experts say devotions of blackmail or sanction poverty and awe of being accused of trying to sabotage the airline and government are part of causes of such dare devil attempts that propel a pilot to fly an aircraft when he knows it is unsafe to do so.Other factors that led to these high accidents rate include mechanical problems pilot errors, faulty landing facilities in our airports absence of floodlights and fallible air dictation facilities. In fact the control dodge is so poor that sometimes pilot have to go along (relate) to each other on weather (visibility and wind speed) situation rather of using the control tower.The result of the correlation analysis model showed that there is a high relationship between poor visibility and aircraft accident reported during these period of study. This is evident from a careful value of 0.85 (72%) and vituperative table value of 0.51 at 0.01 Confidence level. Hence one can now say that poor v isibility did not only disallow aircraft operation, but has resulted in most of the aircraft accidents recorded in Nigeria as shown from the 72% explanation of the correlation. While the rest 28% is accounted for by human errors and unreliable air control facilities and Mechanical problems.Figure 1 depicts the Seasonal occurrence of aircraft accident from 1987 1998. While there were double maximum of aircraft accident occurrence (13) in the month of April and September there is no accident recorded in the month of May. The concentration of fog and mist in the lower surface during the morning hours, in July September, at times reduces visibility to 50m in Bight of Guinea and Coastal areas (Hayward and Oguntoyinbo, 1987), Human errors form the explanation to the highest accident recorded in the season. However the concentrations of aircraft accidents are more in the dry season (October March). This is evident in 9, 7, 6, 8, 9 and 5 recorded during this season. In fact while there is virtually no month during the dry season that has less than 5 cases of accidents, there is in the wet season (April September). This is evident in 13, 0, 4, 6, 9, and 13, recorded during this season. The highest cases of 13 occurrences of aircraft accidents were in the month of September. It is attributed to poor visibility related to heavy rainfall.Causes of Aircraft mishaps in NigeriaTable 2 shows the number of responses to the major causes of aircraft mishaps in Nigeria. Out of the 14 respondents interviewed, all the respondents indicated that poor visibility is a regular cause of aircraft mishaps in Nigeria. This indicates 100% of the respondent. Thus, this is a manakin of the earlier result which show that poor visibility have a operative effects on aircraft accident in Nigeria other factors in decreasing order of responses areas. Lack of regular maintenance (12 respondents) old age of the aircraft (10 respondents) lack of safe landing equipment (9 respondents) human erro rs (6 respondents) improper describe system (5 respondents) and fear of blackmail (4 respondents) this showed that all these factor are the major factors that causes aircrafts mishaps.The result of the multiple regression analysis shows that poor visibility generate 72% of aircraft mishaps in Nigeria. The effects of poor visibility on each of the 5 airports however show that the highest effect was at Sokoto airport with reason r-value of 0.68, and thus representing 47%. Banchi Kano, Kanduna and Lagos airports, with r-values of 0.67. 0.49 and 0.48, followed this respectively. These shows that poor visibility has exerted 45%, 37%. 24% and 23% effects on the prevalence of aircraft mishaps at Banchi, Kano, Kaduna and Lagos airports respectively. However, summary of analysis of variance from the multiple regression analysis shows that poor visibility has strong solid effects on aircraft mishaps in Nigeria during the period of study. This is evident from a calculated F value 4.98 that is greater than the critical table value of 4.39, with 5 under 6 degree of freedom at 0.05 significant level (see table 3).CONCLUSION AND RECOMMENDATIONThe study revealed that poor visibility has significant effect on aircraft mishaps in Nigeria over the period of study. Apart from poor visibility, other causal factors of aircraft mishaps identified are lack of regular maintenance, old age of aircraft, lack of safe landing equipment, human errors, improper reporting system and fear of blackmail of the pilot.Viewing the monumental loses from aircraft accidents accident prevention should be a goal sought by everyone in the aviation industry, as well as by the government.The Meteorological Services department of the Federal Ministry of Aviation should continue to recognise the enormous impact of weather on flying operation, particularly civil and general aviation, and provide services tailored to meet the specific needs of this important part of the aviation sector. Increasing relia nce should be placed on automated systems, as opposed to face-to-face briefing services, to deliver meteorological information for flight planning and pilot documentation.It is also essential that up-to-date training and educational material be made available to enable pilots to enhance their knowledge and understanding of aeronautical meteorology and aeronautical meteorological services, so that they can use that information to fly safely and efficiently.Government should encourage the aviation industry by creating an effective incident-reporting programme. This is done by having reporting systems both at the topical anaesthetic (i.e. airline, air traffic facility etc.) and national levels, with the local sources forwarding information to the national system. For a more co-ordinated level of direct the Nigerian National Voluntary Incident Reporting System (NNVIRS) should voice information at a global level.The modern instrument landing system (ILS) should be installed in major airports in Nigeria. The 19 bleak Distance Measuring Equipment (DME), very high Omni-directional radio range (VOR) on Doppler VOR and locator Beacons installed at two run ways of the Lagos airports should also be installed at all Nigerian internal and International airports to boost domestic and international flights. Also, routine maintenance of aircraft should be carried out as and when due.Accidents just now ever happen without warning. The combination or sequence of failure and slues that causes an accident may indeed be unique, but the individual failure and mistake rarely are. Hence poor visibility was identified as a major casual factor that was responsible for the above aircraft accidents in Nigeria. Other contributing factors include Human error, absence of safe landing equipment, fear of blackmail and lack of regular maintenance of aircraft before they embark on any journey or flight. Finally, it is recommended that accident prevention should be the obligation of ever yone in the aviation industry.REFERENCESAdebayo. S. 1. (1980) Pronounced Dust haze Spell Over Nigeria, 2-11 March, 1971 Pre-WAMEX Symposium. Lagos, 270 300.Adefolalu, D, 0. (1968) Two Case Studies of the Vertical Distribution of Dust during occurrence of Harmattan murkiness over Nigeria. Technical Notes No 21, Met. Department, Lagos, Nigeria, 13 pp.Adefolalu, D, 0. (1983) Weather Forecasting and the affair of Scale hizteraction in West Africa. Arch. Met. Geoph. Bioci. Ser. A32, 103 117 pp.Adefolalu, D, 0. (1984) On Bio-climatological Aspects of Harmatlan Dust haze in Nigeria. Arch. Met. Geoph. Bioci. Ser. B 33 387 404pp.Biglestone, H.J. 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