LAGOS — Nigerian airlines are facing a shrinking market even though foreign exchange is available and jet fuel supply is stable, operators told ThisDay. Aero Contractors Chief Executive Ado Sanusi credited the Dangote refinery with steady fuel supply, while an executive of United Nigeria Airlines said jet fuel now costs about N2,000 per litre, up from N900 before the Iran crisis, and that no Nigerian airline is profitable. A fuel supplier said Dangote now sells jet fuel in dollars.