When you board an aircraft, you might notice a diagonal or straight line just above the door. Have you ever wondered what these are? They’re not just there for decoration. These features are rain gutters, and they’re typically found above each regular door of an aircraft. I’m not entirely certain if emergency exits also have them, but it’s usual for the main doors to be equipped with these gutters.
Rain gutters on passenger aircraft which are typically above cabin doors on the fuselage section, these gutters are designed to divert rainwater away from the aircraft doors. This simple yet effective mechanism ensures passengers remain dry while entering or exiting the aircraft, especially during rainy conditions.
Design and Functionality of Aircraft Rain Gutters
The design of rain gutters on aircraft is a fine balance between functionality and maintaining aerodynamic efficiency. Due to the potential for aerodynamic drag, the size of these gutters is kept to a minimum. However, in heavy rain conditions, this limitation means that gutters may fill and overflow over the door area. To counter this, rain gutters are installed in an inclined position, allowing for rapid drainage of water.
The placement of rain gutters is carefully considered to ensure effective water drainage. Rain gutters above the forward doors of the aircraft are inclined downward in the forward direction, channeling water toward the nose of the aircraft. Conversely, gutters above the aft doors are inclined toward the rear, directing water toward the tail. This strategic positioning ensures efficient water flow away from the cabin doors.
Additional Water Diversion Features
In addition to rain gutters, similar metal strips are found in other parts of the aircraft, such as the Auxiliary Power Unit (APU) access door and the lower surface of the wing near the wing tank vent. These strips serve a similar purpose in managing water flow and preventing it from entering sensitive areas of the aircraft.
The primary purpose of rain gutters is to enhance the passenger experience on rainy days. Without these gutters, passengers would be exposed to a curtain of water flowing down from the upper fuselage upon entering or leaving the aircraft, leading to discomfort and a potentially slippery cabin floor.
While jet bridges offer some protection from rain, they do not cover the entire fuselage. Rainwater falling on the uncovered top area of the fuselage would naturally roll down, potentially entering the doorway. Rain gutters effectively redirect this water flow away from the doorway. In situations where jet bridges are not available, rain gutters become even more crucial in reducing the amount of water entering the cabin.
First love never dies. I fell in love with airplanes and aviation when I was a kid. My dream was to become a pilot, but destiny led me to another path: to be an aviation digital media content creator and a small business owner. My passion for aviation inspires me to bring you quality content through my website and social accounts. Aviation is indeed in my blood and blog!
