Pugachev's Manoeuvre

The Cobra Manoeuvre, also known as Pugachev's Cobra, after the name
of the Russian pilot who first performed publicly this manoeuvre in 1989 on an
SU-27, is a manoeuvre in which the plane initially flying horizontally,
abruptly points up to an angle of attack of 90 degrees or more. This
manoeuvre causes the plane to lose almost all of its horizontal energy
while gaining a little bit of altitude. The manoeuvre can be used to
evade enemy missiles, or get onto a perusing aircraft's tail during
dogfights. Perhaps the most important but unintended effect of
the manoeuvre is "stealth". Aircrafts that use doppler radars cannot see
objects that do not move. Since the manoeuvre loses almost all of
horizontal speed, the plane becomes temporarily invisible to enemy
aircraft, for about 30 seconds.

I know there are people who think an aircraft without energy is a sitting duck. That is true, but the Cobra manoeuvre is not the only manoeuvre that the flanker family can do. Flankers are capable of just about anything, and the Cobra is a special case.