In aerodynamics, the flight envelope, service envelope, or performance envelope of an aircraft refers to the capabilities of a design in terms of airspeed and load factor or altitude. The term is somewhat loosely applied, and can also refer to other measurements such as maneuverability. When a plane is pushed, for instance by diving it at high speeds, it is said to be flown "outside the envelope", something considered rather dangerous.
Flight envelope is one of a number of related terms that are all used in a similar fashion. It is perhaps the most common term because it is the oldest, first being used in the early days of test flying. It is closely related to more modern terms known as extra power and a doghouse plot which are different ways of describing a flight envelope.
Read more about Flight Envelope: Extra Power, Doghouse Plot, Velocity Vs. Load Factor Chart, Sidenotes, "Pushing The Envelope"
Famous quotes containing the words flight and/or envelope:
“Its shrill scream seems yet to linger in its throat, and the roar of the sea in its wings. There is the tyranny of Jove in its claws, and his wrath in the erectile feathers of the head and neck. It reminds me of the Argonautic expedition, and would inspire the dullest to take flight over Parnassus.”
—Henry David Thoreau (1817–1862)
“Geroge Peatty: I’m gonna have it, Sherry. Hundreds of thousands, maybe a half million.
Sherry Peatty: Of course you are, darling. Did you put the right address on the envelope when you sent it to the North Pole?”
—Stanley Kubrick (b. 1928)