While en route to London over Germany on 16 February 2017, Jet Airways flight 9W118 lost communication with air traffic controllers for a short period. As is standard procedure, the German Air Force sent aircraft to investigate. The flight landed in London one hour later without incident. An aircraft following the Jet Airways flight to London managed to capture the interaction on video.
Update: it appears the video has been taken down by the original uploader, though there appear to be several copies available on YouTube.
Flight 9W 118 was flying at FL360 (36,000 feet) when German Air Force jets began escorting the aircraft. Following in trail at FL380 (38,000 feet) was British Airways flight 2042 from Male to London. Based on the angle of the video and the lack of additional aircraft that would have a similar view, it is reasonable to conclude the video was captured from BA2042.
9W 118 maintained its course throughout the loss of ATC communications and subsequent reestablishment and landed in London at 17:46 UTC.
Jet Airways Statement
Jet Airways issued the following statement regarding the incident.
Contact between Jet Airways flight 9W 118, from Mumbai to London Heathrow, of February 16, 2017, and the local ATC, was briefly lost while flying over German airspace. Communication was safely restored within a few minutes. As a precaution, the German Air Force deployed its aircraft to ensure the safety of the flight and its guests. The flight with 330 guests and 15 crew subsequently landed at London without an incident.
Jet Airways has duly reported the matter to the concerned authorities including the DGCA. As part of the standard process, the flight crew of 9W 118 has been de-rostered pending investigation.