Assessment of adverse weather on the operations of air transport at Jomo Kenyatta International Airport and Wilson Airport

Abstract

Air transport is the fastest and safest mode of transport. However, it is the most sensitive to weather. Adverse weather has a major impact on the safety, efficiency and capacity of aviation operations. Aircrafts are more vulnerable to severe weather conditions in the vicinity of aerodromes while taking off and landing which lead to the unavoidable consequences of reduced operating efficiencies due to delays, diversions and cancellation of flights. Meteorological forecasts are therefore an important tool for flight planning which has led to considerable interests in assessing their accuracy, skill and value. This study examined the influence of adverse weather on aircraft operations at Jomo Kenyatta InternationalAirport (JlGA) and Wilson Airport. Using aircraft operations data between 2000 and 2009 for JKIA and Wilson, adverse weather was linked with delays and diversions of aircrafts from both airports. The impacts of delays were measured by the time difference between the expected time of arrival for an aircraft and the actual time of arrival. Poor visibility, thunderstorms and wind shear were found to be the major causes of aircraft delays and diversions. The resultant delays at JKIA and Wilson airports created costs amounting to over 30,000,000 Kenya shillings. The cost of aircraft diversions at JKIA and Wilson airports due to adverse weather was estimated to be 1.9 billion Kenya shillings over the ten years of study. Forecast verification is essential to monitor forecast quality over time, analyze the different sources of uncertainty and skill across the entire forecasting process, and compare the quality of forecasts from different methodologies in order to evaluate forecast skill improvement from new science and technology. Trend type forecast verification is a driver in forecast system development since it assists in understanding of predictability. Using four months trend type forecast for selected hours at JKIA, skill scores for 30 minutes and one and a half hours were computed from a two way contingency table. The skill scores, on average, were found to be higher for the thirty minutes forecast as compared to one and half hours forecast.