What Do Red And Green Lights Mean On A Helicopter?

If you have ever closely observed a helicopter, you must have noticed the red and green lights. In fact, these lights are not only present on helicopters but also on commercial and private airplanes. The red and green lights are crucial in determining the direction in which other airplanes or helicopters are flying in low-light conditions, making night flights safer.

The aviation industry relies on multiple redundant systems to prioritize safety– that's why many commercial aircraft use in-flight radars to detect other aircraft and avoid harsh weather conditions. Moreover, staying in constant contact with the ATC helps avoid collisions, apart from relying on just the red and green lights. However, this system comes in handy for helicopters and smaller airplanes without radars and also acts as an additional safety layer for the more advanced aircraft. Apart from the red and green lights, helicopters sport many more external lights, each serving different functionalities. But how do these lights help pilots determine the direction of other aircraft?

By convention, the red light is placed on the left and the green light is placed on the right of an airplane or helicopter. Apart from this, a white light, a.k.a. tail light is present at the rear end.

Now, imagine you are a pilot flying a plane in the night. It is pitch black outside, and you see red and green lights blinking from your windscreen. The lights clearly indicate there's another aircraft in your proximity, but how do you determine if it is safe to maintain your course, or should you maneuver?

Let's say you see the lights on your left, with the red light positioned to the right of the green light. As per convention, the green light is placed on the right side, meaning the other aircraft has its nose facing you and is approaching you at an angle. You may need to change course or slow down to avoid a collision.

If you only see a green or red light, it indicates an aircraft going either left to right or right to left in front of you. The chance of a collision is remote, but you would want to be careful in this case.

Furthermore, if you see the tail light along with the red light on the left and the green light on the right, it indicates an aircraft going in the same direction as you. This orientation of lights is relatively safe.

Apart from the red and green lights, helicopters are equipped with landing, anti-collision, and searchlights. The landing lights are crucial when landing a helicopter in areas without well-lit helipads. They help illuminate the ground in the front and help pilots make better approaches by giving an idea of the altitude and the terrain below in the dark.

Anti-collision lights include a blinking white light at the bottom and/or a red light at the top of a helicopter. These lights are turned on when the engine turns on to alert the crew about the possible movement of the helicopter, helping in collision avoidance.

Apart from these, specialized helicopters like the U.S. Army's helicopter fleet sport searchlights, which you may recognize from the various helicopter chase sequences depicted in pop culture. Searchlights project a bright beam to illuminate the ground below, similar to how different bright flashlights work but on a much larger scale. These are useful for locating people during pursuits or search-and-rescue missions.