emergency brake

During an emergency that ratio could be allowed to drop to 8.5 people per orbit.
Exclusive: U.S. Drone Fleet at ‘Breaking Point,’ Air Force Says|Dave Majumdar|January 5, 2015|DAILY BEAST
Investigators will focus on whether the sudden emergency was so extreme that no degree of pilot skill would have helped.
Flight 8501 Poses Question: Are Modern Jets Too Automated to Fly?|Clive Irving|January 4, 2015|DAILY BEAST
One specific kind of emergency is at the heart of this, such as when an airplane suffers a loss of stability at night.
Flight 8501 Poses Question: Are Modern Jets Too Automated to Fly?|Clive Irving|January 4, 2015|DAILY BEAST
Had they been properly trained, they could and should have flown themselves safely out of the emergency.
Flight 8501 Poses Question: Are Modern Jets Too Automated to Fly?|Clive Irving|January 4, 2015|DAILY BEAST

This suggests that the pilots were overtaken very rapidly by an emergency.
Did Bad Weather Bring Down AirAsia 8501?|Clive Irving|December 29, 2014|DAILY BEAST
Here there is no question of emergency, or enemy pressure, or of haste; so much we see plain enough with our own eyes.
Gallipoli Diary, Volume I|Ian Hamilton
They tobogganed down hills without a brake at the imminent peril of their lives.
The Joyous Adventures of Aristide Pujol|William J. Locke
The case for emergency contractility, however, is somewhat better than the case for ordinary contractility.
Readings in Money and Banking|Chester Arthur Phillips
I do not know whether they can be manned, but everything is being prepared for any emergency that may arise.
The Philippine Islands, 1493-1898, Volume XX, 1621-1624|Various
As long as an emergency truck could squeeze through at moderate speed, that was enough.
Fee of the Frontier|Horace Brown Fyfe

Origin of emergency brake