Operating IMC with a RIS is safe beyond question in the UK.
I agree totally that IMC flight in uncontrolled airspace without procedural or radar separation is undesireable in the extreme. HOWEVER, on occasions and with lots of caveats and planning it can be done with a level of risk commensurate with other flying training activities.
As illustration. Its a miserable wet Saturday morning with a cloudbase of 1500ft. You have a student needing some IF GH and radio aids work. You pick an area with nice flat terrain handy for a forced landing with late cloud break. You have the area nicely defined by multiple cockpit navaids and groundstations. You ensure said area is not on a diect line between nearby aerodomes, has no airways above it and is in the middle of nowhere. You get a FIS from London and also broadcast on local frequencies where applicable, blind if necessary. You check the mil coordination service prior and also file a VFR flight plan defining your area, times and altitudes for the sortie. You plan two diversion aerodromes that have current weather allowing sensible minimas for instrumental approach. All this extra planning is done with Bloggs in tow as a useful training event in itself.
Having done all that the actual risk of mid air collision is low.
Compare that with the routine close shaves encountered in a busy little airfield on a sunny Saturday afternoon in the summer. Microlights, 5hrs a year PPLīs, solo students and matey boy in his Yak performing running breaks...
Compare that with the routine NDB approaches made by Bloggs with the screens up where you are number 2 with number 1 on a low approach and go around back to the beacon and number 3 is just calling localiser established. Your neck is doing a decent impression of Rod Hull and Emu whilst Bloggs drifts all over the FAT with wildly erratic speed and VSI indications missing checks and gear along the way.
Compare that with the PFL midweek into Farmer Palmers best flat field which attracts every other student in the county plus the local Mil helicopter squadron. You know the field, the one with the flock of birds on it nicking the new seed with the rising ground o the left and the woods to the right and those cables half a mile upwind. Then of course you are in the hangar queen with "the big mag drop" and the slightly over rich mixture for the go around.
Compare that with cruising along on an IMC training flight (say Welshpool to Filton as I remember) at flight level enormous under positive radar control - maybee even an IFR flight plan - but in a Warrior. Whoops! Its all gone quiet, so its drift down time into the Brecon Beacons with an 800ft cloudbase and hill fog expected. Pass me the superman outfit will you - or perhaps you are going to use The Force today.
My basic point is that the comparable risk of a well planned uncontrolled non radar IMC sortie is equal to or less than other routine flying training sortie.
As I stated before - airmanship makes all the difference. Its all very well saying donīt do it sit at home but if thats the job and thats the equipment and the CAA says its legal then sometimes sitting on the ground drinking another coffee is not a viable option. If you want to keep your job. Or pay your rent.
Thats my tuppence haīpenny on a fogged in no-fly day.
Safe flying,
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