The time for dark adaptation is
Which problem may occur, when flying in an environment of low contrast (fog, snow, darkness, haze)?
Under these conditions it is:
A pilot approaching an upslope runway
The area in front of a threshold descends towards the threshold.
Possible danger is:
Sunglasses with variable filtration (phototrope glasses)
What misjudgement may occur if an airplane is flying into fog, snow or haze?
Depth perception when objects are close (< 1 m) is achieved through
Adaptation is