Aircraft Lights: Types and Defintion
On a highway, cars travel in only two directions and at relatively the same speed, making them predictable and (usually) easy to spot. In the sky, however, planes can travel in many different directions - north, south, east, west, everything in between, and even climb and descend at incredible rates. This means that for safety and collision avoidance, civil aircraft must be easy to spot and track in the night sky.
Because of the importance of making airplanes easily identifiable at night, aircraft exterior lighting has been standardized in the United States. In general, the main types of lighting on an airplane are: airplane landing lights, position or aircraft navigation lights, anti-collision lights, and strobe lights. All of these lights serve a very important function, and depending on the type of flight, all may be required on a particular aircraft.
Airplane Lighting Placement and Color
The most recognized aircraft lights are the aircraft navigation or position lights. These lights are located on the wingtip of the aircraft, and are red, green, and white - the navigation light on the left wing is red, while the navigation light on the right wing is green. The final navigation light is located on or near the tail, and is white. The color choice serves to aid pilots in determining the direction of travel of an aircraft, as well as assist in following aerial right-of-way rules.
The airplane anti-collision strobe lights are another easily recognizable light. These lights are flashing white, and are also generally located on the wing for smaller aircraft, or on the fuselage for larger aircraft. These lights are intended to draw attention to the aircraft, ensuring it is not overlooked at night or in poor visibility.
The rotating beacon is a very important light. This light is red, and on many commercial airliners, can be seen on the belly of the fuselage, as well as on the tail. This light is activated just prior to engine start, and will be left on the entire time the engines are running.
The airplane landing light may be one of the most powerful lights on the aircraft, especially on commercial airliners. This light may be seen for miles away when an aircraft is approaching the runway to land. This white light is generally encased in the nose, or in the wing root, and projects a concentrated beam like a flashlight forward.
Legal Lighting Requirements
For Visual-Flight-Rules (VFR) during the day, a general aviation aircraft must only be equipped with anti-collision lights (the red and green wingtip lights, and white tail light).
For VFR at night, the aircraft must be equipped with anti-collision lights (or strobe lights), position lights, and if being flown for hire, a landing light.
For Instrument Flight Rules flight, the general aviation aircraft must be equipped with the same lighting as required for night VFR flight.
The Navigation Lights
The aircraft navigation lights (or position lights) serve an extremely important purpose. These lights are utilized to allow pilots to determine the direction of travel of an aircraft. The left wing navigation light is red, so if a pilot sees red and white lights (the tail navigation light) ahead, he knows that he is viewing the left side of an aircraft that is flying from his right to his left. Likewise, if he or she views green and white lights, (the right wingtip and tail), the pilot is viewing the right side of the aircraft, which is traveling from the pilot’s left to the pilot’s right. If a red light is viewed on the right, and a green light on the left - look out! The aircraft is approaching head-on.
How does this let a pilot determine right-of-way in the air? Airplanes are expected to give the right-of-way to an aircraft on the right. Therefore, if a pilot encounters another aircraft at night, and sees a green and white light, he or she is to the right of the other aircraft, and has the right-of-way. Just like at a stoplight, green means go. If a red and white light are observed, the other aircraft is to the right, and must be yielded to.
Strobe or Anticollision Lights
The aircraft strobes help draw attention to the airplane. These lights will be used when on an active runway, and also when below 10,000 feet. Flashing strobe lights are an excellent method of making other air traffic aware of the airplane. They are turned off when flying through clouds, because the intense flashing effect can be reflected back into the cockpit and cabin by the cloud, causing a blinding effect. Above 10,000 feet, air traffic is equipped with transponders, which allow Air Traffic Control to see pertinent information such as speed and altitude. Because of this, the chances of an aerial collision is lessened, and the strobes can be safely deactivated.
The Rotating Beacon
The red rotating beacon, located on the belly of the fuselage and on the tail, helps to keep ground personnel safe. Before the engines are turned on, the beacon is activated, to warn others that a powerful jet engine or turboprop is about to spool up. This beacon will be active the entire time the engines are running.
The Landing Light
The landing light is an extremely powerful light that may be seen for miles when an aircraft is coming in to land. This light projects outward from the nose or from the wing, and will illuminate the runway for the aircraft when it is close enough. The airplane landing light functions as a giant headlight for the pilot. This light may be active during takeoff, but is always turned on for landing, at day or at night, to increase visibility and safety.
In addition to the landing light, an airplane may have a taxi light, which is less powerful. The taxi light serves to illuminate the area just ahead of the aircraft to allow it to taxi safely without blinding other pilots with the bright landing light.