No luggage! Here is what could have happened to IndiGo's Delhi-Istanbul flight

Oh. The reason?

Passengers were told that it was an operational issue. The company later said “exceptionally heavy headwind" forced it to offload baggage.

What are headwinds?

Thousands of feet above the earth, there are strong winds. Some of these work for, or against, an aircraft. The one that blows against the aircraft's flight are called headwinds.

Think about walking against the wind. It works like that. Headwinds slow down the aircraft, robbing its flight of speed and also consuming more fuel.

But tailwinds help?

Exactly. Opposite to headwinds, tailwinds give a push to an aircraft and add to its speed.

Got it. Basically, the IndiGo flight got slowed down due to headwinds.

That is right. Explains a senior pilot from the industry:

"The headwinds at this time of the year are strong. Which means the “air distance” an aircraft has to fly is more, or in other words, the ground speed of the aircraft is lesser."

How much difference did the headwinds make in the Delhi-Istanbul flight?

The information shared by a travel blogger who goes by the Twitter handle “khabri lal”, shows that the onward journey usually takes about six hours and 40 minutes while the return flight to Delhi covers the distance in about five hours and 20 minutes. Thus, the headwinds were already making travel longer for the Istanbul-bound flights.

On September 16, though, the Istanbul flight took even more time, just three minutes shy of seven hours to reach its destination.

That's pretty long. How does that impact?

Explains the pilot quoted above:

"Strong headwinds mean the aircraft is flying at its limits in terms of the range. Because of the slow pace, aircraft need to carry more fuel for the extra flying time."

But, why did the requirement of more fuel lead to luggage being left behind?

More fuel in a long flight means less “payload” or ability to carry extra weight in terms of passengers or cargo. Reducing payload cuts down on fuel consumption, thus enabling the flight to fly longer.

"In this case they took all the passengers, but were unable to carry the cargo/baggage," adds the pilot.

Does this happen often?

Headwinds, and thus the need to carry more fuel is a common circumstance. But, the inability to carry any of the passengers’ luggage is still rare.

So, have the IndiGo passengers got their luggage back?

We checked with one of the passengers late on September 17. He has not got it yet.