The pilot of the nine-seater chartered plane, which crashed in Faridabad on Wednesday night, was aware of the bad weather conditions within a 100-km-radius of the Indira Gandhi International Airport (IGIA).
As per standard procedure, the Meteorological Department informs the Air Traffic Controller about weather conditions, which later conveys the same to pilots approaching Delhi. It is ultimately the decision of the pilot whether to fly in bad weather or not.
"The pre-monsoon thunderstorm is not ideal for flying. While bigger aircraft can manage in strong winds and thunderstorms, for smaller aircraft, flying in this condition is very difficult," said an ATC officer, requesting anonymity.
According to sources, the pilot of the crashed aircraft was looking for a suitable direction when it hit cumulonimbus (CB) cloud.
"The weather has been changing from May 21. We call it pre-monsoon thunderstorms. In such conditions, cloud levels go up and the plane has to fly below normal heights to avoid clouds. After the incident, we have started getting queries from the ATC and pilots to keep them updated on the weather condition. We are issuing a special weather advisory," said RK Jenamani, met director, IGIA said. "The CB cloud mostly hit Haryana and Punjab," he added.
"We had issued a warning at 8.30 pm on Wednesday and keep the ATC updated, as the weather keeps deteriorating. Since the visibility was also failing, a special report was issued at 9.30pm," Jenamani added.
The Met department also informed the ATC about the change in wind direction from westerly to north-easterly. "Cross wind and turbulence by CB cloud is a lethal combination. That is why the aircraft was diverted to other destinations in case CB cloud is near Delhi," said a met department officer requesting anonymity.
Delhi airport has been witnessing this weather during the past week, even as 42 flights were diverted in a day.
"CB cloud has static charge and entering CB cloud is suicidal. Pilots always avoid CB cloud. Last week, there was a ring of CB cloud over Delhi and pilots had failed to pierce it,” he added.