and increase insurance cover.

Just to clear things up. Nutt's Corner was NOT a licenced model flying area. One of the military VFR routings from the ATZ boundary was via Nutt's Corner below 500ft with no lower limit. In certain areas of Northern Island we had an operational ceiling of 200 ft. AGL. When Aldergrove ATC was aware that there was model flying going on they would warn us but could not prevent OR allow it.

We tolerated it but when they got aggressive then we used this trick. The only mistake I made was that the set was a standard HF set used by long range Transport Command and had an output of 100watts, not 100 mw.

But you obviously haven't flown a military helicopter in an operational environment where the aircraft were ordered to fly as low as possible either below 400 ft agl, or above 2,000 ft to have a good chance of staying alive (where the latter wasn't often an option). Some of us here have quite a lot of experience of doing so. The IRA had declared quite openly that they desperately wanted to shoot down a military helicopter and capture the crew, if they survived. They had the means to do so, and had shot down British military helicopters on more than one occasion, even though it wasn't generally reported in the media at the time, for political reasons.

We were required to carry out regular "Ops Normal" call on HF, btw. I've also seen the "HF" countermeasure applied to 27 Mhz R/C aircraft, although not carried out by myself. It definitely worked. Anyone aiming to cause a hazard to a military aircraft deserves everything they get, AK-47, SAM missile, or a R/C aircraft all count the same. Better a quick blast of HF to discourage them than a squirt from a 7.62 mm machine gun, which we were all equipped with.

My closest call with a R/C aeroplane as a civilian helicopter pilot was actually just north of Brent Reservoir in the Heathrow control zone, directly on the eastern flight path to RAF Northolt. A red and white aerobatic model with a wingspan of about five feet and carrying a tuned pipe along its spine went vertically upwards, just outside of my rotor disc. I was at 1200 feet LHR QNH, in accordance with my clearance from the Heathrow controller.

I have no axe to grind against R/C modellers (I have two R/C models of my own, one a powered aeroplane and a slope soarer glider). Only the ones who are either irresponsible or worse, deliberately endanger an aircraft.