Could an ATCO or pilot answer two questions? Sorry if they're stupid. They're to do with the topic
"No need for R/T at Heathrow ?".
1. What's the difference between VMC and VFR or IMC and IFR?
2. The procedures seem to state that an aircraft experiencing total R/T failure should continue on a flight as planned. What would happen if such a failure occured shortly after departure on a LHR-JFK route? I can see some, errm, eyebrows being raised by the military if this were to happen!