Engine replacement within 4 hrs
Being a cynical engineer, with some experience on props.....one would like to say just two words here........prove it !.....and not in some sanitised hangar with all the available G/equipment....and...ahem, with the aircraft / engines carefully prepared in advance......4 hrs ??.....erm, "just a shade optimistic" I would suggest....but it sounds good in marketing speak I suppose.
Does that 4 hrs also include the ground runs afterwards....or has the total time to do an engine change been quietly forgotten ?