I remember seeing an original RAAF Mirage pilot's flight manual back in the mid-80s and distinctly remember the best glide speed after an engine failure was 360KIAS!!!!!!
The glide ratio, was approximately 2 or 3 to one, that is 2-3 miles over the ground for every thousand feet lost!!!!
As a Mirage driver once said to me, it was easy to establish the glide angle, just throw out house brick and follow it down!!!
A lot different from the approximate 10 to one ratio of a single engine light plane!!!!
You no doubt used that to attempt to get yourself to the high key position.