Posting this while it's still fresh because I want to get the details down properly. Tuesday the 6th of February, approximately 10:55pm. I was standing on the riverbank near Woolwich Arsenal station waiting for a mate who was coming off a late shift. Clear night, cold, maybe 3 degrees, very little cloud cover. There was a bit of ambient noise from the road but the river itself was quiet. I'd been standing there maybe ten minutes when I noticed three lights in a triangular formation moving very slowly westward over the Thames.
The lights were a pale amber colour - not quite orange, not quite white - and they were absolutely silent. That's the thing that got my attention first, the silence. A helicopter would have been audible from that distance easily, and these were low enough that a helicopter would have been deafening. The triangle was quite large, I'd estimate each side maybe the length of a bus or possibly longer, though judging scale at night is obviously difficult. The whole thing moved at a steady, unhurried pace for about forty seconds and then the lights just went out, one after another, starting from the rear-most point.
My mate arrived literally two minutes later and I described it to him straight away so he can corroborate what I said at the time. I did take my phone out to film but by the time I'd unlocked it the lights had already gone. I've reported it to the British UFO Research Association and I'd encourage anyone else who was in the Woolwich or Thamesmead area that night to post here if they saw something. Genuinely stumped.