Why Planes Still Board From The Left — A 1930s Habit That Became An Immutable Rule

Here’s something most people don’t think about, and just take for granted. Nearly all planes board on the left side of the aircraft. Why is that?

• It doesn’t actually matter which side planes board from

• But for the most part they all need to board from the same side so that airports get configured consistently and equipment gets set up consistently.

• This is how ships did it

• And once that became the standard, it was basically locked-in.

Early aviators borrowed terminology and conventions from ships. Ships docked with the port (left) side against the pier, because the steering oar (starboard) was on the right side and would have been damaged otherwise. Pilots and ground crews simply kept that convention: park with the left side toward the terminal.

The captain traditionally sits in the left seat of the cockpit. By approaching the terminal with the left side facing the gate, the captain can see the jet bridge or stairs clearly, making it easier to park precisely at the stand (with or without ground assistance). Meanwhile, the co-pilot on the right can watch for ground crew, fuel trucks, and wing clearance. (There’s no regulation that the pilot in command sit in the left seat. It’s convention.)

Cargo, fueling, and servicing are largely done from the right side of most aircraft. Keeping passengers boarding and deplaning on the left avoids conflicts with ground equipment and reduces risk, especially when using stairs rather than jetbridges.

Emergency vehicles and catering trucks also have standardized positions based on this layout, keeping the ramp choreography consistent worldwide.

Aircraft doors, lavatory service panels, fueling ports, and galley access points are therefore designed with this convention in mind.

• This is mostly true, but it’s not universal. There are planes with refueling panels on the right wing, but also some with a fueling point on the left.

• Cargo aircraft like the Lockheed C-130 Hercules, C-17 Globemaster, or Boeing 747 Freighter are designed around rear or right-side loading for practical ramp logistics.

• Helicopters frequently board on the right. Pilots usually sit in the right seat for better hover visibility (rather than left seat for planes), so passengers naturally enter from the left or right depending on rotor direction and balance. Bell and Airbus helicopters typically use right-side entry. Sikorskys generally use left.

• Some early planes didn’t follow the modern left-boarding rule. de Havilland Comets had doors on both sides. Convair 880/990s were built with optional starboard forward doors. Tupolev Tu-154 and Il-62 had rear air stairs under the tail. Rear airstairs also came with some rear‑engined jets like the 727 and DC-9/MD-80.

However, changing the standard would require a complete redesign of airport gates, jet bridges, and ground procedures – and new planes. It’s simpler just to keep everything the way it is, and that’s been the case since the 1930s.