It is possible to save a few hours this way, as long as you start during your hour-building.
On another thread (which I can't find right now) I explained why I thought an IMC during hour-building is a good idea. Amongst the other reasons, it's possible to do it, near enough, for free. You have to build hours anyway, so the additional cost of having an instructor sat next to you for 15 of those hours is minimal (not to mention the benefits of flying with an instructor from time to time before you let any bad habits set in).
Once you've got the IMC rating, you can then log instrument time in the UK. Either real (not too difficult in the UK!) or, if you take a safety passenger, simulated. I find it's not too difficult to find willing safety passengers when I'm paying for the flying!
This instrument time will count towards the FAA IR. The requirements for the FAA IR are for 40 hours of instrument flying, at least 15 of which are with an FAA CFII. So, if you can fly at least 25 hours on instruments prior to starting your IR, you'll only need a minimum of 15 hours. Add to that the 15 hours to convert it to JAR, and you have a JAR IR for only 30 hours, instead of the usual 45 (or more if you don't have a CPL).
All these numbers are minimums, of course, and don't include the hours for the skills test. They are also for a single-engine IR - I'm not quite sure of the requirements for multi-engine, but I think there is scope for similar savings there too.
FFF
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