Night Operations Flashcards
Two distinct types of light-sensitive cells located in the retina of the eye?
Rods and Cones are the light-sensitive cells located in the retina
What is the function of the cones, and where are they located?
Cones are used to detect color, detail and far-away objects and are located in the center of the retina at the back of the eye. Less sensitive to light, require higher levels of intensity to become active, most useful in the daylight hours
What is the function of the rods, and where are they located?
Rods are located in the back of the eye or retina. Function when something is seen out of the corner of the eye or peripheral vision. Detect objects, particularly moving objects, no detail or color, only shades of gray. Cones and rods are used during day. In the absence of normal light, night vision is 100% on rods
Average time for rods and cones to adapt to darkness
Cones take 5-10 minutes. Rods take 30 minutes.
What should pilot do to accommodate changing light conditions?
Should allow enough time for eyes to become adapted to low light levels, should avoid exposure to bright light which could cause temporary brightness.
Several examples of illusions related to ground lighting conditions
On clear nights, distant stationary lights can be mistaken for stars or other aircraft.
Ground lights (freeway, runway, approach, lights on moving train) can cause confusion
Black-hole approach occurs when landing is made over water or non-lighted terrain where runway lights are only source of light. Without peripheral visual cues to help, pilots have trouble orientating themselves. Runway seems out of position.
Night landings can be complicated by difficulty of judging distance and posibility of confusing approach and runway lights.
Approach lights can make aircraft seem high in turn to final
(Night operations) During takeoff you suddenly feel in excessively nose high-up attitude? What type of illusion is this?
Somatogravic Illusion. A rapid acceleration during takeoff can create the illusion of being in a nose up attude. A pilot disorientated by this might push the nose down or dive attitude.
When approaching a a well-lit runway surrounded by a dark area with little or no features? What illusion should a pilot be alert for?
Featureless terrain illusion- an absence of ground features, as when landing over water, darkened areas, and terrain made featureless by snow; creates the illusion the aircraft is at a higher altitude than it actually is. If unrecognized you’ll fly a lower approach.
What should a pilot do to maintain good eyesight?
Keep physical condition up. Fatigue, colds, vitamin deficiency, alcohol, stimulants, smoking and medication impair vision
What can pilot do to improve effectivness of vision at night?
1) Adapt to darkness 30 minutes prior to flight and keep them adapted. (30 min needed to adjust after exposure to light)
2) Use oxygen if available. At 5,000 feet and above
3) Close one eye when exposed to bright light to help avoid blinding effect
4) Do not wear sunglasses after sunset
5) Move eyes more slowly than in daylight
6) Blink eyes if they become blurred
7) Concentrate on seeing objects
8) Force eyes to view off center
9) Maintain good physical condition
10) Avoid smoking, drinking, and using harmful drugs
What equipment should pilot have for night flight operations?
At least one reliable flashlight, LED producing white/red light and blue for chart reading is preferable. Second backup flashflight. White light for preflight visual inspections, red light for cockpit operations. Spare batteries
Aeronautical Charts
Explain arrangement and intrepretation of position lights on an aircraft
Red light- left wingtip. Green light right wingtip. White light tail.
If you see red on left, green on right. Flying same direction
If you see only red, plane is flying to your left. only green, to your right.
If you see green left and red right. Plane is on colission course
Position lights are required to be on during what period of time?
Sunset to sunrise
When an aircraft is operated in, or in close proxiity to, a night operations area, what is required of an aircraft?
Must be clearly illuminated
Have lighted position lights, or
Be in an area which is marked by obstruction lights
Are aircraft anticollision lights required to be on during night flight operations?
Yes; however PIC can determine because of operation conditions its in best interest of safety to turn lights off.
What are Runway End Identifier Lights (REIL)?
REILs are installed at many airfields to provide rapid and positive identification of the approach end of a particular runway. Pair of synchronized flashing lights located laterally on each side of the runway threshold. Either omnidirectional or unidirectional facing approach area
Describe a Runway Edge Light System
Runway edge lights are used to outline edges of runways during periods of darkness or restricted visibilty conditions. White, except on instrument runways yellow replaces white ont he last 2,000 feet or halfway the runway length, whichesver is less, to form a caution zone for landings. Lights marking the end of the runway emit red for end of runway and green for beginning of runway. High, Medium, Low Intensity Runway Lights, (HIRL MIRL LIRL)
Describe a Runway Centerline Lighting System (RCLS)
Runway centerline lights- installed on some precision approach runways to facilitate landing under adverse visibility conditions.
Located along the runway centerline and are spaced at 50-foot intervals. White until last 3,000 feet. Alternate white and red for next 2,000 feet. Red for last 1,000 feet.
What are Touchdown Zone Lights (TDZL)?
Two rows of transverse light bars disposed symmetrically about the runway centerline. Steady burning white lights 100 feet beyond landing threshoold to 3,000 feet beyond threshold or midpoint of runway, whichever is less
Taxiway edge lights
Outline the edges of the taxiways; blue lights
Taxiway centerline lights
Assist ground traffic in low visibility conditions; Steady burning green lights
Clearance bar lights
Installed at holding positions on taxiways; 3 in-pavement steady burning yellow lights
Runway guard lights
Installed at taxiway/runway intersections; either a pair of elevated flashing lights on either side of taxiway or in-pavement yellow lights installed across the taxiway
Stop bar lights
Used to confirm ATC Clearance to enter or cross an active runway in low vis conditions; Red, unidirectional, steady burning in-pavement lights installed across taxiway and pair of elevated steady burning red lights each side
