Even after leaving JFK minutes before Air India, how come Delta reaches BOM Hours after Air India does?

Question

i've noticed that Air India leaves like hours after Delta leaves JFK(some days becuz of delays..otherwise it's more like 5 mins or so)...but even after leaving after Delta, Air India reaches bombay like an hour b4 delta does..

DELTA(DL16)!!

Departure

Airport:

New York, NY (JFK)

Scheduled Time: 8:55 PM, Jun 06

Actual Time: 10:13 PM, Jun 06

Arrival

Status:Landed

Airport:

BOM

Scheduled Time: 10:10 PM, Jun 07

Estimated Time: 10:21 PM, Jun 07

Time To Arrival: 1 hr 27 min

Flight Details

Aircraft:

Boeing 777-200

AIR-INDIA(AI140)!

Departure

Airport:

New York, NY (JFK)

Scheduled Time: 9:30 PM, Jun 06

Actual Time: 10:40 PM, Jun 06

Arrival

Status: Landed

Airport:

BOM

Scheduled Time: 10:15 PM, Jun 07

Actual Time: 8:15 PM, Jun 07

Flight Details

Aircraft:

Boeing 777-200

Answer 1

I think Air India is a direct flight (Non Stop) and Delta stops at some place, but I wouldn't know fir sure.

Answer 2

My guess is that each airline has a different cost index, meaning Delta probably flies slower to conserve fuel. Air India might have a cost index allowing them to travel at mach .82 and Delta's cost index might only allow mach .78 or something like that. They are nonstop flights. The links below will give you a view of flightplans as well as altitude. Hope I helped!