CHAPTER 12. Night Operations

Orientation and Navigation

At night, it is usually diffi cult to see clouds and restrictions to visibility, particularly on dark nights or under overcast. The pilot fl ying under VFR must exercise caution to avoid fl ying 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, the pilot should use caution in attempting further fl ight in that same direction. Such a halo or glow around lights on the ground is indicative of ground fog. Remember that if a descent to land must be made through fog, smoke, or haze, the horizontal visibility is considerably less. Under no circumstances should a night fl ight be made during poor or marginal weather conditions.

The pilot should practice and acquire competency in straight-and-level fl ight, climbs and descents, level turns, climbing and descending turns, and steep turns. The pilot should also practice these maneuvers with all the fl ight deck lights turned off. This blackout training is necessary if the pilot experiences an electrical or instrument light failure. Training should also include using the navigation equipment and local NAVAIDs.

In spite of fewer references or checkpoints, night cross-country fl ights do not present particular problems if preplanning is adequate, and the pilot continues to monitor position, time estimates, and fuel consumption. The GPS is the most valuable instrument for day and night cross-country fl ying. For night cross-country fl ying, spare batteries or a GPS hooked to the aircraft electric system with a battery backup is recommended. NAVAIDs, if available, should also be used to assist in monitoring en route progress.

Crossing large bodies of water at night in single-engine aircraft is hazardous and not recommended by day or night. This is from the standpoint of landing (ditching) in the water, but especially at night because with little or no lighting the horizon blends with the water making depth perception and orientation diffi cult. During poor visibility conditions over water, the horizon becomes obscure and may result in a loss of orientation. Even on clear nights, the stars may be refl ected on the water surface which could appear as a continuous array of lights making the horizon diffi cult to identify.

Lighted runways, buildings, or other objects may cause illusions when seen from different altitudes. At an altitude of 2,000 feet, a group of lights on an object may be seen individually; while at 5,000 feet or higher, the same lights could appear to be one solid light mass. These illusions may become quite acute with altitude changes and, if not overcome, could present problems in respect to approaches to lighted runways.

 ŠAvStop Online Magazine                                                                                                                                                      Contact Us              Return To Books

AvStop Aviation News and Resource Online Magazine

Grab this Headline Animator