One of the most enticing sights for an aviation geek is the chance to peek into the flight deck when boarding the aircraft. It does not take much to notice that the flight deck's door is wide open while the aircraft is being prepared for departure, but do you know the reasoning behind the globally followed procedure? Let's take a look into the matter and find out why this is the case.

A pilot's job extends to more than merely flying the plane

Overall, cockpit doors need to be kept open due to the number of people who must enter and exit the flight deck before departure. For instance, the First Officer is required to leave to conduct an external walk-around preflight before returning. Along with this, keeping the door open allows the Captain to monitor the boarding procedure. Of course, non-pilots may also come in and out.

Many ground staff members are also meant to keep in continuous contact with the pilot, including technicians, fueling staff, and those responsible for the cleaning and catering of the aircraft. All in all, the cockpit can be a bustling place before a flight pushes back.

POV from the captains seat in a Boeing 737 Cockpit.
Photo: Joe Kunzler | Simple Flying

The same is true during deplaning as well. The cockpit doors are usually open at that time, allowing lucky passengers to peek inside and even have a chat with pilots by the door. With several ground staff members liaising with the pilots and performing their duties, opening and closing the door each time would be pretty inefficient.

Not just pilots in the cockpit

An airplane undergoes several essential checks before a flight, so a technician needs to provide airworthy approval to the pilots before they are cleared to commence operations. Fueling staff provide the pilots with a fueling slip to confirm if the proper quantities are loaded in the right tanks. While we have touched upon pilots and ground staff, we mustn't forget that flight attendants also come and go.

Indeed, the cabin crew of a given flight is responsible for coordinating with the pilots during the boarding process, providing them with a list and count of passengers onboard the flight. This information is provided along with any last-minute changes that may have occurred during the boarding process, such as missing passengers, canceled transits, or upgrades in traveling class.

​​​Once the pilots are satisfied with the information they have received from the different departments working on getting the plane ready, they order the door to be locked. After this, they are subsequently able to begin communicating with the air traffic controllers concerning their pushback and take-off clearance. Once ready, the cockpit doors are usually kept closed for the flight's duration.

There are only a few situations in which the cockpit door is opened during a flight. One is when pilots change shifts on a long-haul flight or while one goes to the bathroom mid-flight. Even this requires a special procedure, with cabin crews blocking the galley entrance (usually with a cart) to prevent anyone else from entering. Some airlines even draw the curtain at the front of the plane to keep the entry and exit of pilots as hidden as possible.

The second situation in which the cockpit door is opened midflight is when the crew serves pilots their inflight meals. Of course, any entry or exit from the cockpit requires the Captain or pilot-in-charge's permission before occurring, including cabin crew members.

No more flight deck visits

Avgeeks of a certain age will remember the exciting experience of being allowed a visit to the flight deck as children. Back in the late 20th century, this was common practice, with children invited up to see the cockpit and, in certain situations, even getting the inspiring opportunity to try on the Captain's hat. These days, the best you can do is catch a glimpse during boarding or deplaning and, if you're really lucky, see the cockpit in a non-commercial setting (aircraft launch, tour, etc.).

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However, since the attacks on September 11th, 2001, security arrangements in this regard have become much more stringent. As such, the door to the flight deck is usually kept locked shut throughout the entire duration of the flight, and no passengers are invited up to see the wonders of the cockpit anymore. These rules are strictly enforced, too, with Starlux Airlines Founder and A350 Captain Chang Kuo-wei being handed a fine for allowing popular YouTuber Sam Chui into the cockpit on the airline's inaugural flight between Los Angeles and Taipei.

Which other aviation practices make you look for the reasoning behind them? Have you ever visited the flight deck? Let us know your thoughts and experiences in the comments!