Three India-bound Boeing 787 Dreamliners have been forced to return back to base within a 36-hour period after being hit with problems. The Air India passenger jets -the same type as the aircraft involved in last week's tragedy in Ahmedabad- suffered a mix of issues from a bomb threat to a technical glitch.

Aircraft is one of the most advanced jets in service and experts say it has a generally strong safety record, with no previous fatal accidents

The deadly crash of Air India Flight 171 last week has centered renewed scrutiny on the airplane's manufacturer, Boeing, and this time it's the 787 Dreamliner in investigators' sights. The accident, which killed over 270 people,