Cockpit - Ergonomics

Ergonomics

The first airplane with an enclosed cabin appeared in 1912 on the Avro Type F; however, during the early 1920s there were many passenger aircraft in which the crew remained open to the air while the passengers sat in a cabin. Military biplanes and the first single-engined fighters and attack aircraft also had open cockpits, some as late as the Second World War when enclosed cockpits became the norm.

The largest impediment to having closed cabins was the material the windows were to be made of. Prior to Perspex becoming available in 1933, windows were either safety glass, which was heavy, or cellulose nitrate (i.e.: guncotton), which yellowed quickly and was extremely flammable. In the mid 1920s many aircraft manufacturers began using enclosed cockpits for the first time. Early airplanes with closed cockpits include the 1924 Fokker tri-motor, the 1926 German Junkers W.34 transport, the 1926 Ford Tri-Motor, the 1927 Lockheed Vega, the Spirit of St. Louis and the passenger aircraft manufactured by the Douglas and Boeing companies during the mid-1930s. Open-cockpit airplanes were almost extinct by the mid-1950s, with the exception of training planes, crop-dusters and homebuilt aircraft designs.

Cockpit windows may be equipped with a sun shield. Most cockpits have windows that can be opened when the aircraft is on the ground. Nearly all glass windows in large aircraft have a Anti-reflective coating, and an internal heating element to melt ice. Smaller aircraft may be equipped with a transparent aircraft canopy.

In most cockpits the pilot's control column or joystick is located centrally (centre stick), although in some military fast jets and in some commercial airliners the pilot uses a side-stick (usually located on the outboard side and/or at the left).

The layout of the cockpit, especially in the military fast jet, has undergone standardisation, both within and between aircraft different manufacturers and even different nations. One of the most important developments was the "Basic Six" pattern, later the "Basic T", developed from 1937 onwards by the Royal Air Force, designed to optimise pilot instrument scanning.

Ergonomics and human factors concerns are important in the design of modern cockpits. The layout and function of cockpit displays controls are designed to increase pilot situation awareness without causing information overload. In the past, many cockpits, especially in fighter aircraft, limited the size of the pilots that could fit into them. Now, cockpits are being designed to accommodate from the 1st percentile female physical size and the 99th percentile male size.

In the design of the cockpit in a military fast jet, the traditional "knobs and dials" associated with the cockpit are mainly absent. Instrument panels are now almost wholly replaced by electronic displays, which are themselves often re-configurable to save space. While some hard-wired dedicated switches must still be used for reasons of integrity and safety, many traditional controls are replaced by multi-function re-configurable controls or so-called "soft keys". Controls are incorporated onto the stick and throttle to enable the pilot to maintain a head-up and eyes-out position – the so-called Hands On Throttle And Stick or HOTAS concept,. These controls may be then further augmented by new control media such as head pointing with a Helmet Mounted Sighting System or Direct Voice Input (DVI). New advances in auditory displays even allow for Direct Voice Output of aircraft status information and for the spatial localisation of warning sounds for improved monitoring of aircraft systems.

The layout of control panels in modern airliners has become largely unified across the industry. The majority of the systems-related controls (such as electrical, fuel, hydraulics and pressurization) for example, are usually located in the ceiling on an overhead panel. Radios are generally placed on a panel between the pilot's seats known as the pedestal. Automatic flight controls such as the autopilot are usually placed just below the windscreen and above the main instrument panel on the glareshield. A central concept in the design of the cockpit is the Design Eye Position or "DEP", from which point all displays should be visible.

Most modern cockpit will also include some kind of integrated warning system.