Robert Moore wrote:
Dudley Henriques wrote

Coffin corner is the area behind the curve where sink rate
can't be stopped with power but requires reduction in angle of attack.
For a perfect example of an aircraft in coffin corner, see the Edwards
AFB accident involving a young AF pilot who got his F100 so deep into
coffin corner behind the curve he couldn't recover the airplane; not
enough air under him to reduce the angle of attack. He applied full
burner but couldn't fly it out on power alone. Reduction of angle of
attack was what he needed and he didn't have the room. THIS is the
definition of coffin corner and it most certainly IS in the area of
reverse command.

You're kidding, right? Better stick to light plane flight instructing
Dudley. I sure don't see the F-100 pilot anywhere near critical mach
speed. THAT was NOT a case of "coffin corner".

From Wikipedia, the free encyclopedia
Coffin corner (aviation)
The coffin corner or Q-Corner is the altitude at or near which an
aircraft's stall speed is equal to the critical Mach number, at a given
gross weight and G loading. At this altitude the aircraft becomes nearly
impossible to keep in stable flight. Since the stall speed is the
minimum speed required to maintain level flight, any reduction in speed
will cause the airplane to stall and lose altitude. Since the critical
Mach number is maximum speed at which air can travel over the wings
without losing lift to flow separation and shock waves, any increase in
speed will cause the airplane to lose lift, or to pitch heavily nose-
down, and lose altitude. The "corner" refers to the triangular shape at
the top of a flight envelope chart where the stall speed and critical
Mach number lines come together. Some aircraft, such as the Lockheed U-
2, routinely operate in the "coffin corner", which demands great skill
from their pilots.[1]


From Wikipedia, the free encyclopedia
Slow flight
Slow flight is a portion of an airplane's performance envelope above the
speed at which the plane will stall, but below the aircraft's endurance
speed. This part of the performance chart is also known as "the back
side of the power curve" because when flying in this area, more power is
required in order to go slower and still maintain straight and level
flight. A large angle of attack is required in order to maintain the
altitude of the aircraft.

Bob Moore
For God's sake Moore, try actually READING these posts before shooting
off your mouth once in a while. Our mutual dislike for each other is
legendary by now.
As usual, you are beating a dead horse here. Coffin corner is explained
in full in several posts above.
The use of the term is correct in BOTH instances!

--
Dudley Henriques