Chapter 6

Oral Exam Preparation Questions and Answers
CHAPTER 6

NIGHT OPERATIONS
A. Night Preparation

1. Name the two distinct types of light-sensitive cells located in the retina of the eye. (FAA-H-8083-25)

Rods and cones are the light-sensitive cells located in the retina.

2. What is the function of the cones, and where are they located in the eye? (FAA-H-8083-3)

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.

3. What is the function of the rods, and where are they located in the eye? (FAA-H-8083-3)

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.

4. What is the average time it takes for the rods and cones to become adapted to darkness? (FAA-H-8083-3)

The cones will take approximately 10-15 minutes to adjust to darkness. The rods will take approximately 30 minutes to adjust to darkness.

5. What should the pilot do to accommodate changing light conditions? (FAA-H-8083-3)

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.

6. Give several examples of illusions related to ground lighting conditions. (FAA-H-8083-3)

a. On a clear night, distant stationary lights can be mistaken for stars or other aircraft. Certain geometrical patterns of ground lights, such as a free way, runway, approach, or even lights on a moving train can cause confusion. Dark nights tend to eliminate reference to a visual horizon.
b. 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 (down sloping or up sloping) and in the worse case, results in landing short of the runway.
c. 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.

7. When approaching a well-lit runway surrounded by a dark area with little or no features, what illusion should a pilot be alert for? (AIM 8-1-5)

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.

8. What should the pilot do to maintain good eyesight? (FAA-H-8083-3)

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

9. What can the pilot do to improve the effectiveness of vision at night? (FAA-H-8083-3)

a. 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.
b. 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.
c. Close one eye when exposed to bright light to help avoid the blinding effect.
d. Do no wear sunglasses after sunset.
e. Move the eyes more slowly than in day light
f. Blink eyes if they become blurred
g. Concentrate on seeing objects
h. Force the eyes to view off center
i. Maintain good physical condition.
j. Avoid smoking, drinking, and using drugs that may be harmful.

10. What equipment should the pilot have for night flight operations? (FAA-H-8083-3)

At least one reliable flashlight is recommended as standard equipment on all night flights. A D-cell size flashlight with a bulb switching mechanism that can be used to select white or red light is preferable. 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.

11. What other items should the pilot have on board for night flights? (FAA-H-8083-3)

Pilots should have appropriate navigational charts, including any charts adjacent to the intended route of flight on board for night flight. These charts should be mounted on a clipboard or map board to prevent being lost in the dark cockpit.

12. Explain the arrangement and interpretation of the position lights on an aircraft. (FAA-H-8083-3)

A red light is located on the left wing tip, a green light is located on the right wing tip and a white light is located on the tail. If the pilot observes both a green and red light on another aircraft, then the other aircraft is generally approaching the pilot’s position. If the pilot sees only a green light, then the other aircraft is moving left to right in relation to the pilot’s position. If the pilot sees only a red light, then the aircraft is moving right to left in relation to the pilot’s position.

13. Position lights are required to be on during what period of time? (14 CFR 91.209)

From sunset to sunrise.

14. When an aircraft is operated in, or close proximity to, a night operations area, what is required of an aircraft? (14 CFR 91.209)

The aircraft must:
a. Be clearly illuminated,
b. Have position lights, or
c. Be in an area which is marked by obstruction lights.

15. Are aircraft anti-collision lights required to be on during night flight operations? (14 CFR 91.209)

Yes; however, the anti-collision lights need not be lighted when the pilot-in-command determines that, because of operating conditions, it would be in the interest of safety to turn the lights off.

16. What are Runway End Identifier Lights (REIL)? (AIM 2-1-3)

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 Omni directional or unidirectional facing the approach area.

17. Describe a Runway Edge Light System. (AIM 2-1-4)

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. Examples are: High Intensity Runway Lights (HIRL), Medium Intensity Runway Lights (MIRL), and the Low Intensity Runway Lights (LIRL).

18. Describe a Runway Centerline Lighting System (RCLS). (AIM 2-1-5)

Runway centerline lights – 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.

19. What are Touchdown Zone Lights (TDZL)? (AIM 2-1-5)

Touchdown zone lights 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 3.000 feet beyond the landing threshold or to the midpoint of the runway, whichever is less.

20. Describe several different types of taxiway lighting. (AIM 2-1-9)

a. Taxiway edge lights – outline the edges of taxiways; consist of blue lights.
b. Taxiway centerline lights – assists ground traffic in low visibility conditions; consists of steady-burning green lights.
c. Clearance bar lights – installed at holding positions on taxiways; consist of three in-pavement steady-burning yellow lights.
d. 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.
e. 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, undirectional, steady-burning in-pavement lights installed across the taxiway and a pair of elevated steady burning red lights on each side.

21. What are the different types if rotating beacons used to identify airports? (AIM 2-1-8)

a. White and green Lighted land airport
b. *Green alone Lighted land airport
c. White & yellow Lighted water airport
d. *Yellow alone Lighted water airport
e. Green, yellow & white Lighted heliport
f. White (dual peaked & green) Lighted military airport
*Green alone or yellow alone is used only in connection with a white and green or white and yellow beacon display respectively.

22. Describe several types of obstruction lighting. (AIM 2-2-3)

a. Aviation red obstruction lights – flashing aviation red beacons and steady burning aviation red lights during nighttime operations.
b. 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.
c. 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.
d. Catenary lighting – medium and high intensity flashing white markers for high voltage transmission lines and support structures.

23. How does a pilot determine the status of a light system at a particular airport? (FAA-H-8083-3)

The pilot needs to check the Airport / Facility Directory and any Notices to Airmen (NOTAMs) to find out about available lighting systems, light intensities and radio-controlled light system frequencies.

24. How does a pilot activate a radio-controlled runway light system while airborne? (AIM 2-1-7)

The pilot activates radio-controlled lights by keying the micro phone on a specified frequency. The following sequence can be used for typical radio controlled lighting systems:
a. On initial arrival, key the microphone seven times to turn the lights on and achieve maximum brightness.
b. If the runway lights are already on upon arrival repeat the above sequence to ensure a full 15 minutes of lighting.
c. The intensity of the lights can be adjusted by keying the microphone five or three times within 5 seconds.

B. Night Flight

1. During preflight what things should be done to adequately prepare for the night flight? (FAA-H-8083-3)

a. Study all weather reports and forecasts. Particular attention should be directed towards temperature / dew point spreads to detect the possibility of fog formation.
b. 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.
c. Obtain applicable aeronautical charts for both the proposed route as well as adjacent charts, and mark lighted check-points clearly.
d. Review all radio navigational aids for correct frequencies and availability.
e. Check all personal equipment such as flashlights and portable transceivers for proper operation.
f. The aircraft should be thoroughly preflighted.
g. All aircraft position lights, as well as the landing light and rotating beacon, should be checked for proper operation.
h. Ground areas should be checked for obstructions that may not be readily visible from within the cockpit.

2. What are some guidelines to follow during the starting, taxiing, and run-up phases of a night flight? (FAA-H-8083-3)

a. 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.
b. During taxing, avoid unnecessary use of electrical equipment which would put an abnormal load on the electrical system, such as the landing light. Additionally, other pilots taxing in the area can be blinded by your landing light or strobes, so avoid using them during taxiing.
c. Taxi slowly and follow any taxi lines.

3. What are some of the guidelines to follow during takeoff and departure phases of a night flight? (FAA-H-8083-3)

a. During takeoff the pilot should:
• 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, and
• Upon liftoff, keep a positive climb by referencing the attitude indicator along with positive rate of climb on the vertical speed indicator.
b. During climb out:
• Do not initiate any turns until reaching safe maneuvering altitude, and
• Turn the landing light off after climb.

4. What should the pilot do to provide proper orientation and navigation during a night flight? (FAA-H-8083-3)

a. 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.
b. 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, built only on dual flights with a flight instructor.
c. Practice the above maneuvers with all the cockpit lights turned OFF – this type of “blackout” training will prove helpful later on, in the even t of an electrical or instrument light failure. Include the use of the navigation equipment and local NAVAIDs in this exercise.
d. Continually monitor position, time estimates, and fuel consumed. NAVAIDs, if available, should be used to assist in monitoring en route progress.

5. If an engine failure occurs at night, what procedures should be followed? (FAA-H-8083-3)

If the engine fails at night, the same procedures apply for dealing with the situation in the day time. Maintain positive control of the airplane – do not panic. A 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 your radio. Declare an emergency, stating WHO you are, WHERE you are, and WHAT your intentions are. In some cases, where radar is available (Approach Control, Center, etc.) you may obtain a quick vector to the nearest airport if within gliding distance. If you have done your homework, you planned your route of flight within gliding distance of lighted airports. If not, two possibilities exist for emergency landing areas:

Lighted Areas – 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 upon. Disadvantages include all kinds of obstructions to deal with, such as wires, poles, traffic, etc.

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 (electrical, fuel) and open the doors.

Whatever your decision, maintain positive control of the aircraft all the way down. A controlled crash will always be more survivable than an uncontrolled crash.

6. What procedures should be followed during the approach and landing phase of a night flight? (FAA-H-8083-3)

a. The pilot should identify the airport and associated airport lighting and runway lighting.
b. The aircraft should be flown towards the airport beacon until the runway lights are identified.
c. A powered approach should be used because visual perception during a descent at night can be difficult.
d. The landing light should be switched on upon entering the airport traffic area.
e. The pilot should avoid the use of excessive speed on approach and landing.