Night Flight related Flashcards
Explain the physiological aspects of night vision.
Must expose rods as opposed to cones to objects.
Do this by looking 5-10 degrees off center of object to be seen. If you look directly at it, it will disappear or dim but if off center it will not. Also need dark adaptation, about 30 minutes, avoid bright white light - use red light if possible
What is the purpose of the cones in your eyes? How about rods?
The cones are responsible for all color vision, from appreciating a glorious sunset to discerning the subtle shades in a fine painting. Cones are present throughout the retina, but are concentrated toward the center of the field of vision at the back of the retina. They work better in high light levels.
The rods are better able to detect movement and provide vision in dim light. The rods are unable to discern color but are very sensitive at low-light levels. Unlike cones which are at the very center of the visual field, rods are further away from the fovea, and provide the major portion of vision.
Where are position lights located on an aircraft and what is their purpose?
A red light is positioned on the left wingtip, a green light on the right wingtip, and a white light on the tail. This arrangement provides a means to determine the general direction of movement of other airplanes in flight. If both a red and green light of another aircraft are observed, and the red light is on the left and the green to the right, the airplane is flying the same direction. Care must be taken not to overtake the other aircraft and maintain clearance. If red were on the right and green to the left, the airplane could be on a collision course.
4 types of rotating beacons?
White and green - Lighted land airport.
White and yellow - Lighted water airport.
Green, Yellow, White - Lighted heliport.
White, white, green - Military airport.
How to handle engine failure at night?
- positive control / best glide speed
- trouble shoot & try to restart
- communicate
- if you know the terrain around you, navigate to an unlit area for landing
- consider trying to land near civilization to aid in your recovery
- maintain wind orientation
- landing light on and checklists
How are obstructions near an airport lit at night?
Aviation red, or white lights, or a combination of both, usually either steady or flashing.
Anti Collusion vs position (nav) lights
position/nav: red (left), green (right), white (tail/aft)
anti collusion: beacon light, strobes
What are the various definitions of “night” and how do they affect your operations?
Navigation Lights – per FAR 91.209 (a) – you cannot operate an aircraft without operating lighted position lights from Sunset to Sunrise.
Recent Flight Experience – per FAR 61.57 (b) – no person may act as pilot in command of an aircraft carrying passengers during the period of 1 hour after sunset and ending 1 hour before sunrise, unless in the proceeding 90 days that person has made at least three takeoffs and three landings to a full stop during the period beginning 1 hour after sunset and ending 1 hour before sunrise.
Logging Night Time – per FAR 1.1 – the definition of night time is the time between the end of evening civil twilight and the beginning of morning civil twilight, as published by the American Air Almanac, converted to local time.
