The Herc a lash up search aircraft?
Why do you think the J model was delivered with a large square window in the para doors and an observers seat mounted on those doors.
Mk1 eyeball SAR was designed into the Herc 4/5 at the outset.
Its a lash up if the crew are not trained and experienced in SAR ops. Searching vaste expanses of water requires trained observers as well as the flight deck. How much experience do the crew have at dropping survival equipment to a floating target? I've done it for real in high seas and it is not easy and takes alot of dedicated practice (D807).
Good luck to the C-130 crew, but again this exposes the UK's capability gap since the demise of the Nimrod MR2/MRA4.