FH1100,
Yes the number of engines makes a difference. Singles are single pilot VFR, twins are 2 pilot IFR. Singles are crashing with monotonous regularity in USA at night and bad WX because they are flying beneath cloud and becoming CFIT statistics or getting disoriented and crashing.
Twin engine machines firstly have two pilots - one of whom can be detailed to get a last minute weather check whilst the other preps the machine. Then they can discuss the weather and their options before departure. if they choose to go then they have the option of flying above fog or in cloud to get to the destination and if they can't land then they divert because they have the equipment and fuel reserves to do that.
John R81,
If this VFR machine came apart in the air whilst flying in fog (cloud) then my guess is that it came apart due to unintentional aerobatics caused by loss of situational awareness - not mechanical failure.
What concerns me most is not why these pilots keep doing it - it is why the medical crews blindly follow them to the scene of the accident. The medical crews that i fly with (in a 2 pilot, twin engine machine) want a detailed weather brief before they will go anywhere. They have no intention of following me to an early grave.