what information is available from a flight envelope?

Question

This is a question relating to flight envelopes for an aircraft. They're used to illustrate the performance etc. But what else? What information? Drag? LIft? Speed?

Answer 1

One of the most basic flight envelopes defines the condition extremes under which a given aircraft with given weight can sustain level flight. See ref. The coordinates are airspeed and either air density or altitude. From this envelope one can easily find the maximum and minimum (takeoff, stall) speeds, maximum speed at a specified altitude, and maximum altitude.
There are many other kinds of envelope, where (for instance)maximum maneuvering accelerations in g, cargo capacity or glide ratio are plotted as a function of altitude or speed. Most envelopes are influenced by, and therefore defined for specified values of, sea-level air pressure and temperature. Some envelopes are purely functions of power and airfoil characteristics, and others may have additional constraints (i.e., portions of the envelope border) defined by airframe strength limits.

Answer 2

A preliminary report will be released at 1pm today when the highly trained investigators have examined the wreck, as the pilot did a superb job of bringing the plane down safely, everything is there for them to examine. It is far more likely that there was either a fuel feed problem or multiple bird strikes, also, because of the congestion at Heathrow, many pilots complain about having to fly around with dangerously low fuel levels, that's why they need another runway.....