Did anyone hear the one, possibly two extremely loud propellor jobs that flew over London today around 11.30am +/- 30mins. They were within 5 mins of each other. I was in slumber catching up on the effects of insomnia and it woke me up, but not enough to check! Super loud/deep/resonating. I don't think that it had the tone of an A400, more AN-?? yet stronger.