There are a lot of posts on this thread where people are touting their own opinions as being "fact".
Just because a particular pilot does not feel it is safe to fly an IFR trip without an autopilot, that does not mean that it is not safe for another pilot.
It all depends on your experience level, your currency, your knowledge of the route, your knowledge of the aircraft, etc, etc, etc. If a pilot regularly flies IFR without an autopilot, and flies the same route (or small selection of routes) every week (and therefore knows all the reporting points, ATC gotchas, etc), and maybe has a moving map GPS, and the weather is fairly benign (solid IMC is fine, but not so bumpy you have to work hard to fly S+L), then I would guess that this particular pilot could fly those routes incredibly safely. Almost everyone who passes a UK IR is in current practice at doing this (but not quite everyone...), so if a pilot were to get an IR and then continue to hand-fly similar routes to his IR there is no reason he shouldn't be able to do so safely.
On the other hand, as a private pilot, it is up to you to assess your currency and ability, and if you don't feel you can undertake the flight safely, then don't do it.
For me, personally, I'd use the autopilot every time if it was there. But if it wasn't there, it wouldn't be a no-go item.
The original question asked about an IMC rating. I would say that, after a 15 hours course, you are not in a position to be able to carry out flights of this length in solid IMC safely. But if that is what you are planning on doing, then find yourself a good instructor, and do 30-40 hours on the IMC course instead of the 15 hour minimum, then go for it. There's nothing that says that a course can't be extended to cover what the student actually needs to get out of it!
A couple of other misconceptions on this thread. Autopilot has been allowed on single-pilot IR renewal flights for quite some time, and in fact was actively encouraged by the examiner the one time I was lucky enough to renew my IR on an aircraft with a funcational autopilot! But it must be switched off for the approaches.
And, as of recently, it is also allowed on initial IR flights too. Although most schools' aircraft don't have autopilots, those schools with shiny new DA42s teach their students to use the autopilot on their IR. I believe that the requirement is for the student to hand-fly to top of climb, and to hand fly the approaches. For the rest of the flight the autopilot can be used, but the pilot is expected to keep a Plog to commercial airline standards.
FFF
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