I think that the ducted fan was used because it was a new and cool idea.
I don't have the hours some other people do on the type, but got to do an evaluation on it a few years back and whilst I enjoyed it enormously, thought it was a poor aircraft for the police role.
There were some handling issues - particularly (if my memory is reliable) a spiral instability I didn't like for safe and accurate low level flying. More significantly however were the poor payload (full fuel and 2 crew with no kit, or about 1/3 fuel with 3POB IIRC), the ballast issue John already mentioned, the lack of any stowage for mission kit (cameras and the like), the lack of anywhere to put the large raft of comms gear that a police operator will want, and that it is only certified for day-VMC.
The ground handling I thought was also a bit of an issue - the 45ft wingspan would give issues at many GA airfields (I'm sure it was fine at Hurn - but imagine trying to say drop into Elstree), and the offset nosewheel with its asymmetric turning circle was entertaining.
And whilst I thought that the bubble nose was gorgeous for sitting observing the world go past - or presumably observing bad people underneath - the 90ish knot max level flight speed was presumably a factor of that, the fan, and the big wing, and a bit limiting, as well as unimpressive with a 240hp engine.
Most of which good engineering could probably fix. Night and IMC capability wouldn't be that hard to achieve, modern FEA could redesign the structure lighter, and airborne handling glitches can be ironed out. The ground handling could be tolerated in a smallish patch with a reasonable number of decent airfields, and some technological solution to the ballast issue can probably be design. In the 21st century, it also wants a Garmin or similar glass cockpit. I don't get the impression that John Edgley however really wanted to hear those sort of suggestions from me or anybody else.
I have a real soft spot for the aeroplane: it was something that particularly inspired me into aeronautics as a teenager, but rather doubt that it will sell in 2016 when for example the Seabird Seeker is on the market with a full CofA and production capability. Somebody would have to put significant effort into revising the Optica to compete with what else is out there now, and I have doubts that anybody is going to pay for that.
Incidentally at the same time that I was being inspired by the Optica as a teenager, and an elderly Neville Duke was test flying it, the young engineer running a lot of the flight test engineering was one Francis Donaldson. Gratuitously dropping names, Paul Mulcahy - later CAA's Chief Test Pilot and presently test flying the PC24 at Pilatus did his ETPS pilots assessment exercise in 1992 on the Optica, with Neville Duke as his safety pilot - presumably just before JF took over. It's an aeroplane with quite an interesting fan club!
G
Last edited by Genghis the Engineer; 8th Mar 2016 at 06:26.