Bomb hoaxes on board two flights? A Sahara plane bound for Kathmandu searched in Delhi, a Jet Airways plane arriving from Delhi, returning to Delhi, searched in Kathmandu...
does sounds like it was coordinated... and not just the act of some teenager trying to stop his girlfriend from taking off...
So if they were planned and coordinated... who would have done it? Let's see who has to gain:
(1) As sajhabusaima said... it could be the people who want to "prove" the existence of terrorists in Nepal.
(2) It could be people trying to portray Nepal as an unsafe destination. (Remember the post-Indian Airlines hijacking era?).
(3) It could be rival airlines who have something to gain from Sahara and Jet exiting the market. But which one? RNAC, Indian Airlines and Druk Air are government owned and operated, and don't seem to be profit driven. And the only other airline is Cosmic Air, which appears to have large sources of hidden money with which it can play "pricing games" to get rival airlines to make losses...
(4) who else???