Red Bull race pilot narrowly escapes death after accelerated stall. The aircraft was at full speed in a tight bank.
Bad things happen when you jerk aircraft controls. In 1959 a new Braniff B-707 had 3 of its 4 engines ripped off during a demo flight because the pilot pulled up too hard out of a deadly spiral dive.
You can stall an airplane at any speed and any attitude.
A common cause of military fighter pilots death is “accelerated stalls” where they pull the stick back too quickly during terrain avoidance or a dive and die. They often are traveling just below the speed of sound and 300mph or more above their normal stall speed. The root cause is “load factor”.
An airplane wing can stall at any attitude and any airspeed. Most airplane handbooks publish only flaps-up and flaps-down stall numbers, and most pilots practice stalls only at those speeds. Many stalls happen at speeds higher than these slow, controlled speeds. They’re called accelerated stalls, and they can happen if the airplane is headed straight up, straight down, or anywhere in between. Generally, accelerated stalls are brought on by turning or by making abrupt control inputs.
Load factor
When an airplane turns or quickly changes pitch attitude, its load factor, or airframe stress, increases. That’s the feeling of being pulled down harder in the seat. Regardless of the type of airplane, the load factor increases at a predictable rate.
The biggest impact of load factor is on stall speed. It increases at the square root of the load factor. A 45-degree bank increases stall speed by 18 percent, and a 60-degree bank angle will stall two times the normal speed!
[A rough analogy using a car is the steering wheel being turned too abruptly and the tires start skidding so the car crashes because it continues straight off a curve. If an airplanes controls are jerked quickly enough, it will stall instead of changing direction.]
