(Abdul Sattar Azad) Airline operations were first identified with environmental hazards in 1950 when the turbine engine aircraft made their debut for commercial transportation. The major noticeable effect was the exhaust plumes from “The engine. In the last 50 years, it has been realized time and again that air­craft tot) have an adverse effect on the environment, particularly the air qual­ity, noise level, and the ozone layer.

As the number of aircraft has multiplied to meet the competition between different countries, the dis­charge of pollutants into the atmo­sphere continues to mount without let or hindrance.

The operations at the Karachi air­port too have gone up by leaps and bounds in recent years. The num­ber of landings and take-offs, for instance, increased from 9,198 in 1950-51 to 12,356 in 1960-61, whereafter it almost doubled and aggregat­ed 22,281 in 1970-71. There were the next ten years when landings, take-offs totaled 37,689 in 1980-81. In 1990-91, the total operation from 25 in 1950-51 to 125 in 1990-91. With the operation of airlines in the private sector, this number has increased to over 175 and again more than double in recent years.

Air pollution    

Emission of carbon monoxide, hydrocarbons, and nitrogen oxide takes place in different proportions during an aircraft’s off. Calculating on the basis of 125 landings and takes-off daily, the pollution load is estimated at 0.25 tons of sulfur dioxide, 3.125 tons of nitrogen oxides, 5.8 tons of carbon monoxide, and 0.18 ton of particulate matter which includes 0.02 kg of the cancer-producing substance, benzopyrene, per day. The macro-environment of the airport is thus charged with acidic fumes and hazardous material.

The pollution load may not appear. appreciable and it could be argued that the vast open area between the runway and the residential colonies produces the desired dilution effect to reduce the hazards of emissions. The pollution load also does not appear to be high compared to that emitted by Karachi’s vehicular traffic which amounts to 170 tons of carbon monoxide alone. The impact of the latter is on the city of Karachi while that of the former is restricted to the residen­tial area surrounding the airport.

Thus people residing in Malir Cantonment, Model Colony, Malir Extension Colony Gulshan-e-Jamal, and Gulistan-e-Jauhar receive the shower of aircraft pollution and are vulnera­ble to some disease hitherto unknown to them.

Noise pollution

The landing of an aircraft is accompanied by a loud road and the noise level approximates 95 to 110 dB at the runway and 75-80 at a distance of 3 km where the residential colonies of Gulshan-e-Jamal Malir Cantonment and Model Colony are located.

At Pahalwan Goth and the army barracks in Malir Cantonment which are directly under the flyway of the air-crafts, a peak noise is obviously of brief duration but it is erratic and unpredictable and creates a highly stressed condition for the population living in the goths and the residential buildings in the Malir Cantonment and the barracks housing the army personnel. In recent years the airline operations at the Karachi airport have become a perpetual source, of nui­sance for more than one million peo­ple, particularly at night when the background noise level is reduced to 55 to 65 dB due to thinner traffic. It may be pointed out that night opera­tions are not undertaken at the air­ports of the industrialized countries.

High altitude flights

Nitrogen oxides as noted above, are among the major air pollutants discharged by the combustion of the jet fuel. The pollutant reacts with ozone and destroys it. Supersonic air­craft may not generate very high quan­tities of nitrogen oxides but they have the capability to release them at high altitudes. The introduction of super­sonic flights can, therefore, be instru­mental in the depletion of the protec­tive ozone layer. The depletion of layers by the chlorofluorocarbons, CFCs, has been duly noted by the industrialized countries, and CFCs production is being regulated. Due concerns have also been shown by the world/community on the role of the supersonic flights and Pakistan should fol­low the example because the area north of the Quetta-Multan axis is vul­nerable to the adverse effects of ozone layer depletion and there could be an increase in the incidence of skin can­cer and cataracts there.

Impact on health

Studies on the ill-effects of noise from aircraft reaching a level of 95 to 105 dB 560 times a day on a communi­ty resident three to five km away resi­dent three to five km away from the airport suggest a 20% higher mortality rare in all cases compared to residents at a distance of 10 to 15 km. Noise-induced stress causes hypertension, heart problems, and a variety of ail­ments. The nervous breakdown has also been noted among residents who live in close proximity to airports. The stress pattern has become all too familiar and has manifested in a vari­ety of ways including an interruption in communication and conversation and transient psychosis.

High rise building

As new colonies come up and the population density around the Karachi airport multiplies, adding to the stress and anxiety of the city’s dwellers, it is time that plans were taken in hand for another airport at the earliest.

On May 22, 2020, a PIA A320 plane from Lahore to Karachi crashed in a densely populated area near Karachi airport killing 97 of the 99 passengers and crew members on board. A teenage girl on the ground also died later.

The plane crash took place in the Model Colony area. the plan probably due to some technical fault crashed over residential area of Model Colony Karachi resultantly about 12 houses and some cars were damaged and heavy human casualties.

It may be noted that no high-rise buildings or multi-storied houses lay on the final approach of the Heathrow. The investigators in finalizing their crash report must also take note of the mushroom growth of housing colonies around the Jinnah International Airport among the other reasons.