ULCCs know how to 'work the metal harder': Indigo Partners

Indigo Partners managing partner Bill Franke, speaking at the CAPA Americas Aviation Summit, commented (17-Apr-2018) that ULCCs have a cost advantage on other LCCs because they know how to "work the metal harder". He explained it is not uncommon for ULCCs to operate aircraft 12 to 13 hours a day compared to LCCs which operate aircraft as low as six hours a day.