Maiden flightThe maiden flight, also known as first flight, of an aircraft is the first occasion on which it leaves the ground under its own power. The same term is also used for the first launch of rockets. The maiden flight of a new aircraft type is always a historic occasion for the type and can be quite emotional for those involved. In the early days of aviation it could be dangerous, because the exact handling characteristics of the aircraft were generally unknown. The maiden flight of a new type is almost invariably flown by a highly experienced test pilot.
Aircraft design processThe aircraft design process is a loosely defined method used to balance many competing and demanding requirements to produce an aircraft that is strong, lightweight, economical and can carry an adequate payload while being sufficiently reliable to safely fly for the design life of the aircraft. Similar to, but more exacting than, the usual engineering design process, the technique is highly iterative, involving high-level configuration tradeoffs, a mixture of analysis and testing and the detailed examination of the adequacy of every part of the structure.
Uncontrolled decompressionAn uncontrolled decompression is an undesired drop in the pressure of a sealed system, such as a pressurised aircraft cabin or hyperbaric chamber, that typically results from human error, structural failure, or impact, causing the pressurised vessel to vent into its surroundings or fail to pressurize at all. Such decompression may be classed as explosive, rapid, or slow: Explosive decompression (ED) is violent and too fast for air to escape safely from the lungs and other air-filled cavities in the body such as the sinuses and eustachian tubes, typically resulting in severe to fatal barotrauma.
Type certificateA type certificate signifies the airworthiness of a particular category of aircraft, according to its manufacturing design (type design). Certification confirms that the aircraft of a new type intended for serial production, is in compliance with applicable airworthiness requirements established by the national air law. For up to three seats, primary category aircraft certification costs around US1m,US25m for a general aviation aircraft and hundreds of millions of dollars for a commercial aircraft; certification delays can cost millions of dollars and can decide a program's profitability. V speedsIn aviation, V-speeds are standard terms used to define airspeeds important or useful to the operation of all aircraft. These speeds are derived from data obtained by aircraft designers and manufacturers during flight testing for aircraft type-certification. Using them is considered a best practice to maximize aviation safety, aircraft performance, or both. The actual speeds represented by these designators are specific to a particular model of aircraft.