Russian airframer Irkut claims 11 operators are carrying out analysis of the MC-21, as it bids to increase the twinjet type's order count.
Irkut states in a first-quarter corporate update that the MC-21 still has 175 firm orders, a figure that has remained unchanged for a considerable time.
But it points out that it has an agreement of intent for three aircraft from Angara Airlines, and that it has presented the aircraft to a total of 247 carriers and lessors at various events and meetings.
Eighty-nine companies have shown interest, says the manufacturer, and 11 airlines are "conducting in-depth studies".
Irkut has newly flown a second MC-21-300 test aircraft, complementing the initial airframe which was first flown on 28 May last year.
Over the course of 2017, says Irkut, the first MC-21 carried out 32 test flights.