Night Operations

Question 1

Name the two distinct types of light-sensitive cells located in the retina of the eye.

Answer 1

Rods and cones

Question 2

What is the function of the cones and where are they located in the eye?

Answer 2

The 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. They are less sensitive to light, require higher levels of intensity to become active, and are most useful in the daylight hours.

Question 3

What is the function of the rods and where are they located in the eye?

Answer 3

Rods are located in the back of the eye or retina. The rods function when something is seen out of the corner of the eye or peripheral vision. They detect objects, particularly those that are moving, but do not give detail or color - only shades of gray. Both the cones and the rods are used for vision during daylight. In the absence of normal light, the process of night vision is placed almost entirely on the rods.

Question 4

What is the average time it takes for the rods and cones to become adapted to darkness?

Answer 4

Approximately 5 to 10 minutes for the cones to become adjusted to darkness. About 30 minutes for the rods to become adjusted to darkness.

Question 5

What should the pilot do to accommodate changing light conditions?

Answer 5

The pilot should allow enough time for the eyes to become adapted to the low light levels and then should avoid exposure to bright light which could cause temporary blindness.

Question 6

Give several examples of illusions related to ground lighting conditions.

Answer 6

1) On a clear night, distant stationary lights can be mistaken for stars or other aircraft. Certain geometrical patterns of ground lights, such as a freeway, runway, approach, or even lights on a moving train can cause confusion. Dark nights tend to eliminate reference to a visual horizon.

2) A black-hole approach occurs when the landing is made from over water or non-lighted terrain where the runway lights are the only source of light. Without peripheral visual cues to help, pilots will have trouble orientating themselves relative to Earth. The runway can seem out of position (downsloping or upsloping) and in the worse case, results in landing short of the runway.

3) Night landings can be complicated by the difficulty of judging distance and the possibility of confusing approach and runway lights. For example, when a double row of approach lights joins the boundary lights of the runway, there can be confusion where the approach lights terminate and runway lights begin. Under certain conditions, approach lights can make the aircraft seem higher in a turn to final, than when its wings are level.

4) If you stare at a stationary light too long, it will start to look like it is moving with you. To fix this, look away from the light for a brief period of time.

Question 7

During takeoff you suddenly feel as if the aircraft is in an excessively high nose-up attitude. What type of illusion is this?

Answer 7

Somatogravic illusion. A rapid acceleration during takeoff can create the illusion of being in a nose-up attitude. A pilot disoriented by a somatogravic illusion may respond by pushing the aircraft into a nose low or dive attitude.

Question 8

When approaching a well-lit runway surrounded by a dark area with little or no features, what illusion should a pilot be alert for?

Answer 8

Featureless terrain illusion - An absence of ground features, as when landing over water, darkened areas, and terrain made featureless by snow, can create the illusion that the aircraft is at a higher altitude than it actually is. The pilot who does not recognize this illusion will fly a lower approach.

Question 9

What should the pilot do to maintain good eyesight?

Answer 9

Good eyesight depends upon physical condition. Fatigue, colds, vitamin deficiency, alcohol, stimulants, smoking, or medication can seriously impair vision.

Question 10

What can the pilot do to improve the effectiveness of vision at night?

Answer 10

1) Adapt the eyes to darkness prior to flight and keep them adapted. About 30 minutes is needed to adjust after exposure to a bright light.

2) If oxygen is available, use it during night flying. Significant deterioration in night vision can occur at cabin altitudes as low as 5,000 feet.

3) Close one eye when exposed to bright light to help avoid the blinding effect.

4) Do not wear sunglasses after sunset.

5) Move the eyes more slowly than in daylight.

6) Blink the eyes if they become blurred.

7) Concentrate on seeing objects.

8) Force the eyes to view off center.

9) Maintain good physical condition.

10) Avoid smoking, drinking, and using drugs that may be harmful.

Question 11

What equipment should the pilot have for night flight operations?

Answer 11

At least one reliable flashlight is recommended as standard equipment on all night flights. A reliable incandescent or light-emitting diode (LED) flashlight able to produce white/red light and blue for chart reading is preferable. Include a second flashlight (such as a head-mounted type) as a backup. The white light is used while performing the preflight visual inspection and the red light is used when performing cockpit operations. A spare set of batteries is also recommended.

Question 12

What other items should the pilot have on board for night flights?

Answer 12

Aeronautical charts are essential for night cross-country flight and, if the intended course is near the edge of the chart, the adjacent chart should also be available. It is also recommended to have a spare set of batteries for the flashlight readily available. Organize equipment and charts and place them within easy reach prior to taxiing.

Question 13

Explain the arrangement and interpretation of the position lights on an aircraft.

Answer 13

A red light is positioned on the left wingtip, a green light on the right wingtip, and a white light on the tail. 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 in the same direction. Care must be taken not to overtake the other aircraft and to maintain clearance. If red were on the right and green to the left, the airplane could be on a collision course.

Question 14

Position lights are required to be on during what period of time?

Answer 14

From sunset to sunrise

Question 15

When an aircraft is operated in, or in close proximity to, a night operations area, what is required of an aircraft?

Answer 15

The aircraft must:

1) Be clearly illuminated

2) Have lighted position lights

3) Be in an area which is marked by obstruction lights

Question 16

Are aircraft anticollision lights required to be on during night flight operations?

Answer 16

Yes; however, the anticollision lights need not be lighted when the PIC determines that, because of operating conditions, it would be in the interest of safety to turn the lights off.

Question 17

What are the three definitions of night?

Answer 17

14 CFR 1.1 - The time between the end of evening civil twilight and the beginning of morning civil twilight, as published in the Air almanac, converted to local time. Use this definition when logging night flight time. (Approximately 1/2 hour after sunset and before sunrise.)

14 CFR 61.57 - The period beginning one hour after sunset and ending one hour before sunrise. Use this definition when determining currency to act as PIC carrying passengers.

14 CFR 91.209 - The period from sunset to sunrise. Use this definition to determine when you are required to have position and anti-collision lights on.

Question 18

What are runway end identifier lights (REIL)?

Answer 18

REILs are installed at many airfields to provide rapid and positive identification of the approach end of a particular runway. The system consists of a pair of synchronized flashing lights located laterally on each side of the runway threshold. REILs may be omnidirectional or unidirectional facing the approach area.

Question 19

Describe a runway edge light system.

Answer 19

Runway edge lights are used to outline the edges of runways during periods of darkness or restricted visibility conditions. They are white, except on instrument runways yellow replaces white on the last 2,000 feet or half the runway length, whichever is less, to form a caution zone for landings. The lights marking the ends of the runway emit red light toward the runway to indicate the end of runway to a departing aircraft and emit green outward from the runway end to indicate the threshold to landing aircraft. These light systems are classified according to the intensity or brightness they are capable of producing.

High intensity, medium intensity, low intensity.

Question 20

Describe a Runway Centerline Lighting System (RCLS).

Answer 20

Installed on some precision approach runways to facilitate landing under adverse visibility conditions. They are located along the runway centerline and are spaced at 50-foot intervals. When viewed from the landing threshold, the runway centerline lights are white until the last 3,000 feet of the runway. The white lights begin to alternate with red for the next 2,000 feet and for the last 1,000 feet of the runway, all centerline lights are red.

Question 21

What are touchdown zone lights (TDZL)?

Answer 21

TDZL consist of two rows of transverse light bars disposed symmetrically about the runway centerline. The system consists of steady-burning white lights which start at 100 feet beyond the landing threshold and extend to 3,000 feet beyond the landing threshold or to the midpoint of the runway, whichever is less.

Question 22

Describe several different types of taxiway lighting.

Answer 22

Taxiway edge lights - Outline the edges of taxiways; consist of blue lights.

Taxiway centerline lights - Assist ground traffic in low visibility conditions; consists of steady-burning green lights.

Clearance bar lights - Installed at holding positions on taxiways; consist of three in-pavement steady-burning yellow lights.

Runway guard lights - Installed at taxiway/runway intersections; consists of 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 visibility conditions; consists of a row of red, unidirectional, steady-burning in-pavement lights installed across the taxiway and a pair of elevated steady burning red lights on each side.

Question 23

What are the different types of rotating beacons used to identify airports?

Answer 23

White and green - Lighted land airport

Green alone - Lighted land airport

White and yellow - Lighted water airport

Yellow alone - Lighted water airport

Green, yellow, and white - Lighted heliport

White (Dual peaked and green) - Lighted military airport

Question 24

Describe several types of obstruction lighting.

Answer 24

Aviation red obstruction lights - Flashing aviation red beacons and steady burning aviation red lights during nighttime operations.

Medium and high intensity white obstruction lights - May be used during daytime and twilight with reduced intensity for nighttime operation. Not normally installed on structures less than 200 feet.

Dual lighting - A combination of flashing aviation red beacons and steady-burning aviation red lights for nighttime operations and flashing high intensity white lights for daytime operation.

Catenary lighting - Medium and high intensity flashing white markers for high voltage transmission lines and support structures.

Question 25

How does a pilot determine the status of a light system at a particular airport?

Answer 25

The pilot needs to check the Chart Supplement and any NOTAMs to find out about available lighting systems, light intensities, and radio-controlled light system frequencies.

Question 26

How does a pilot activate a radio-controlled runway light system while airborne?

Answer 26

Keying the microphone on a specified frequency.

1) On initial arrival, key the microphone seven times to turn the lights on and achieve maximum brightness

2) If the runway lights are already on, repeat the above sequence to ensure a full 15 minutes of lighting

3) The intensity of the lights can be adjusted by keying the microphone seven, five, or three times within 5 seconds

Question 27

During preflight, what things should be done to adequately prepare for the night flight?

Answer 27

1) Study all weather reports and forecasts. Particular attention should be directed towards temperature/dewpoint spreads to detect the possibility of fog formation.

2) Calculate wind directions and speeds along the proposed route of flight to ensure accurate drift calculations, as night visual perception of drift is generally inaccurate.

3) Obtain applicable aeronautical charts for both the proposed route as well as adjacent charts, and mark lighted checkpoints clearly.

4) Review all radio navigational aids for correct frequencies and availability.

5) If a GPS is being used for navigation, ensure that it is working properly before the flight. All necessary waypoints should be loaded properly before the flight and the database should be checked for accuracy prior to taking off, and then checked again once in flight.

6) Check all personal equipment such as flashlights and portable transceivers for proper operation.

7) The aircraft should be thoroughly preflighted.

8) All aircraft position lights, as well as the landing light and rotating beacon, should be checked for proper operation.

9) Ground areas should be checked for obstructions that may not be readily visible from within the cockpit.

Question 28

What are some guidelines to follow during the starting, taxiing, and run-up phases of a night flight?

Answer 28

1) The pilot should exercise extra caution on clearing the propeller arc area. The use of lights prior to and after engine startup can also alert persons in the area to the presence of the active aircraft.

2) During taxiing, avoid unnecessary use of electrical equipment which would put an abnormal load on the electrical system, such as the landing light. Additionally, other pilots taxiing in the area can be blinded by your landing light or strobes, so avoid using the during taxiing.

3) Taxi slowly and follow any taxi lines.

Question 29

What are some of the guidelines to follow during takeoff and departure phases of a night flight?

Answer 29

1) During takeoff, the pilot should:
a) On the initial takeoff roll, use both the distant runway edge lights as well as the landing light area to keep the aircraft straight and parallel in the runway
b) Upon liftoff, keep a positive climb by referencing the attitude indicator along with positive rate of climb on the vertical speed indicator.

2) During climbout:
a) Do not initiate any turns until reaching safe maneuvering altitude
b) Turn the landing light off after climb

Question 30

What should the pilot do to provide proper orientation and navigation during a night flight?

Answer 30

1) Exercise caution to avoid flying into clouds or a layer of fog. Usually, the first indication of flying into restricted visibility conditions is the gradual disappearance of lights on the ground. If the lights begin to take on an appearance of being surrounded by a halo or glow, use caution in attempting further flight in that same direction, as this is indicative of ground fog.

2) Practice and acquire competency in straight-and-level flight, climbs and descents, level turns, climbing and descending turns, and steep turns. Recovery from unusual attitudes should also be practiced, but only on dual flights with a flight instructor.

3) Practice the above maneuvers with all the cockpits lights turned off - this type of “blackout” training will prove helpful later on, in the event of an electrical or instrument light failure. Include the use of the navigation equipment and local NAVAIDs in this exercise.

4) Continually monitor position, time estimates, and fuel consumed. NAVAIDs, if available, should be used to assist in monitoring enroute progress.

Question 31

If an engine failure occurs at night, what procedures should be followed?

Answer 31

If the engine fails at night, the same procedures apply for dealing with the situation in the daytime. Maintain positive control of the airplane. Normal glide should be established and maintained and the airplane turned toward an airport or away from congested areas. A check should be made to determine the cause of the engine failure, such as position of the magnetos, fuel selectors, or primer. If unsuccessful in restart procedures, select 7700 on the transponder and 121.5 on the radio. Declare an emergency, stating who you are, where you are, and what your intentions are. In some cases, where radar is available, you may obtain a quick vector to the nearest airport if within gliding distance.

Two emergency landing areas:
1) Lighted area - Interstate highways, roads, parking lots, etc. Advantages include being able to see where and what you are landing on, and having a relatively improved surface to land on. Disadvantages include all kinds of obstructions to deal with, such as wires, poles, traffic, etc.

2) Unlighted areas - Dark areas with relatively few lights indicating an open area such as a field, lake, etc. Advantages include few or no obstructions to deal with. Disadvantages include not being able to see what you have selected to land on until illumination by your landing light, and the higher possibility that what you have selected is unimproved, rough terrain, etc. As nearly as possible, land into the wind, with flaps, at minimum approach speed. Complete a pre-landing checklist and immediately before touchdown, secure all systems and open the doors.

Question 32

What procedures should be followed during the approach and landing phase of a night flight?

Answer 32

1) The pilot should identify the airport and associated airport lighting and runway lighting.

2) The aircraft should be flown towards the airport beacon until the runway lights are identified.

3) A powered approach should be used because visual perception during a descent at night can be difficult.

4) The landing light should be switched on upon entering the airport traffic area.

5) The pilot should avoid the use of excessive speed on approach and landing.

Question 33

What is good operating practice concerning the use of aircraft lighting while on the ground at night?

Question 34

Why is it especially important to maintain an organized cockpit when flying at night?

Question 35

When conducting an airplane preflight for a local night flight, in addition to those involved in all flights, what are some general items that you should include?

Question 36

When flying VFR at night, in addition to flying an altitude appropriate for the direction of flight, what else can a pilot do to minimize risk?

Question 37

Explain the various types of cockpit and exterior lighting equipment installed in your airplane. What lighting equipment is required by regulation for night flight?

Question 38

Describe the difference between aircraft position lights and anti-collision lights.

Question 39

Why is it especially important pilots be current in basic attitude instrument flying procedures when flying at night?

Question 40

During the enroute segment of a night flight, how can a pilot determine they are flying from VFR conditions to potentially marginal VFR or IFR conditions?

Question 41

When planning a night flight, what weather information should be particularly significant to the pilot?

Answer 41

D

Question 42

Discuss your method of route and checkpoint selection, when planning a night VFR cross-country flight.