Originally Posted by
Innominate
I saw a tweet yesterday from a 747 pilot who said that the second represented the pilot's eye height in the flare.
Here are the marks in question on the Block C offices at Cranebank:
The legend on the photo does indeed suggest that the both discs relate to pilot's eye height.
That said, a quick back-of-the envelope calculation would suggest that the greatest eye-to-wheel height achievable in the flare on a 747, just short of striking the tail, would be about 15 m, compared with the aforementioned 9 m eye-to-wheel height when taxying. But the upper disc in the photo looks to be at least twice as high above ground level as the lower one, although the parallax makes it hard to be sure (any photogrammetry experts out there?).
I believe the building in question may have now gone, so it looks like we might never get a definitive answer.
https://www.reddit.com/r/flying/comm...eight/cuphyl3/