Jet Airways gains 3.7 pct.
Shares up 64.8 pct since Nov. 25, as of Monday’s close.
Oil dives 4 pct to five-year low on oversupply worries.
Every $1/bbl fall in crude can boost company’s FY16 oper profit estimate by 4-5 pct – Analysts.
Weakness at rivals will also boost sales – Traders.
India’s SpiceJet cuts fleet size to save costs.