OK, some more good words here, but I can tell you this. Helicopters are detectable by modern air-to-air radars and can be engaged with modern airborne weapons.
With respect, you guys may be confusing close-quarters evasion training with the real world. If you want a fighter to get tied up with you in a visual fight for training purposes and then believe that that's how it's going to be for real then good luck to you.
I mean no disrespect to the helo community whatsoever. I think the FJ guys -if you'll let them - would be a much better ally to you than you think. But, you shouldn't think that the fighters cannot find and kill you. Fortunately, and contrary to the tone from some of the helo guys here, RAF fighters are actually on your side.