The closure of Pakistani airspace for more than 24 hours and Indian airspace for about six hoursthrew the flight plans of several airlines out of gear, leading to changes in routes, increased flying times, additional refueling stops, and deployment of additional crewmembers on Wednesday and Thursday, according to multiple officials familiar with the matter.

While all airports in Pakistan were shut for take-offs and landings from Wednesday morning to Friday afternoon (barring a few take-offs on Thursday afternoon),nine airports in north India -- Jammu, Srinagar, Amritsar, Pathankot, Leh, Shimla, Kangra, Pithoragarh and Kullu --were shut from 8.30am to 2.30pmas tensions escalated between the two sides after the first air raids in 48 years by fighter jets deep across the Line of Control (LoC).

Manyinternational airlines, such as Air Canada and Emirates, cancelled their flights from Delhiand low-cost Indian carriers, IndiGo and Spicejet, were forced to factor in extra costs to operate longer route.

Air India spent about Rs 15 lakh extra per flight to the US and Europe due to extra flying time, said people familiar with the development.

On Wednesday, there were a total of 47 cancellations. Four other flights destined for other airports that were diverted to Delhi . On Thursday, due to the closure of Pakistani airspace, 12 arrivals and 12 departures were cancelled from Delhi airport , said an airport official.

“Consequent to Wednesday’s airspace and airports closure, Airports Authority of India (AAI) introduced contingency procedures/routes to facilitate transit of overflying flights across the Indian Peninsula. On Wednesday night, air traffic was significantly heavy in Mumbai Flight Information Region (FIR), as all flights were entering/exiting Indian airspace over Arabian Sea to/from Muscat (FIR), due to total closure of Pakistan airspace,” said a spokesperson for AAI .

Flights departing from Delhi and bound for the Gulf or Europe were forced to take a detour to avoid Pakistan airspace.

“Emirates can confirm that due to the airspace closure over Pakistan on 27th and 28th February, flight EK510 on 28th February Dubai to Delhi had to be re-routed, extending the total flight time outside of the crew’s maximum working hours. A replacement crew was arranged to comply with crew working legalities and the aircraft will depart with a delay of 4 hours,” a spokesperson for Emirates said.

A similar statement was issued by Lufthansa. “ In addition to our routes to India, connections to Bangkok and Singapore are also affected. We are already preparing adjusted routings and will increase the amount of additional fuel in the event of delays. ,” said a spokesperson .

In a statement, Qatar Airways said “due to the ongoing situation on the India-Pakistan border” its flights airports in Pakistan were temporarily suspended and passengers travelling to and from Pakistan or India “are advised to check the status of their flights”

British Airways said it was monitoring the situation closely.

On the domestic travel front, GoAir announced schedule changes and fee adjustments for some flights operating to or from Chandigarh, Srinagar, Jammu and Leh, and Jat Airways said its flight schedules were being moderately affected.

Passengers were stranded in Jammu and Srinagar but airlines said the backlog was cleared on Thursday. Airlines have also announced a waiver in cancellation and date changes charge. “Those who have already booked have not cancelled the booking but if the situation prevails, we might see cancellation from tourists,” said Subhash Goyal, secretary of federation of associations in Indian tourism and hospitality, adding the worst may be over.

First Published: Mar 01, 2019 00:03 IST