VFR flight plan and IMC
A question for those who know more about flight rules than I do.
Yesterday (after waiting for the cloud to lift a bit) I filed a VFR flight plan from Blackbushe to an airfield in northern France. However it was clear from the 215 and the METAR that as soon as I got to about 1000ft I would be in IMC, and that the cloud probably extended to the base of Class A airspace at least for the first 10 mins or so (I am IMC rated).
As it turned out this is exactly what happened. As soon as I was clear of the circuit and not wanting to stay at 1000ft under the clouds I got a RIS from Farnborough and was able to level at 2500ft in IMC from there until approaching GWC, when I was able to climb further and be VFR on top, and it was plain sailing from there. (Northern France was VMC and so was the return journey).
My question is: can I just file VFR if I know that I will be in IMC for part of the route and, if so, how much is reasonable. Beyond this limit should file as IFR, or am I not allowed to do this without an IR? Or can I file IFR and decline any clearances into Class A Airspace?