Chris,
I also just noticed that apart from the frequency/wavelength, the whole installation is pretty much like a longwave broadcasting station. Those use much the same transmitter power, between 0.5 MW and 2 MW, mostly. The wavelength is about 10 times less, e.g., BBC longwave operates on 1500 metres.
Now I have no recollection of airliners bouncing all over the sky all over Europe when passing over a longwave transmitter (and there are a fair number).
I think we can lay this one to rest......