increasing head movements to maintain adequate lookout.

resting one's head on the back of the seat and keeping the eyes open.

fixing one's gaze on a stable, distant horizon.

bending the head forward when reading maps and checklists.

1,2 and 3.

3 and 4.

1 and 2.

2, 3 and 4.

flying over high terrain in good visibility.

suddenly flying over small trees after prolonged flying over tall trees.

decelerating at low altitude.

accelerating at low altitude.

speak fast and loudly.

feel more relaxed.

have improved vision

 be physically more active.

Skin disorder

pain in the thorax and a cough.

CNS disturbances

pain in the joints.

loss of peripheral vision.

increase the rate of alcohol elimination from the blood.

intensify the effects of the drugs.

show undesired effects only during night flights.

compensate for side effects of drugs.

It varies over the course of the day and is highest early in the morning.

It is constant throughout the body.

The average body temperature is lower in people from cooler climates.

It is roughly the same for all people, if they are adapted to the place they are.

AIDS and gonorrhea.

TB and dengue.

Cholera and dysentery.

Heat stroke and a chlamydia.

limited to daytime using the rod cells.

almost equally shared by the entire retina.

 limited to the foveal area of the retina.

governed by peripheral vision over an area of approximately 20 degrees of angle.

 lack of mobility of the cornea.

 clouding of the lens.

mis-shapen cornea.

lack of accommodation at the cornea.