An helicopter in the evening

Two days ago in the evening, I heard the rather loud noise of rotors, well, rotating. When I lifted my eyes, I saw a huge helicopter, the same kind I had seen back in February. Maybe a Boeing Chinooks, but I am no expert so can't be certain. It was probably flying from or to Sandhurst. I tried my best to take a few snapshots. This is the best picture I managed to take of the machine. It looked far more impressive live.