Re: the link you directed me to - 2nd post.
"2. There is
no strict relevance to operations in PC1 or to Cat A standards, as the
procedures developed for such operations specifically avoid the HV curve and are
detailed in a separate FLM supplement".
All UK Police Operations are conducted according to PC1/CAT A standards.
As factual as that statement may be, it only applies to take-off and landing procedures and has little bearing on an aircraft in flight which experiences an engine failure while within the HV curve (as defined by Press Alt, OAT, air(wind) speed and aircraft weight).