A friend who's landed on the Burj al Arab helipad many times tells me .......
"The pad is 850'AMSL. Due to the +45C summer temperatures the DA can be 4,500'.
Typically, in the afternoon, due to sea breezes, the surface wind is 300/20. Because of the structure being shaped like a huge sail, the wind on the helipad can be 120/20.
It makes for a very tricky approach what with the size of the structure, the turbulence and the 180 degree shift in wind on the final stage!
After shutting down, the vertigo, as experienced by most high time helicopter pilots, can be very uncomfortable!"