> It will be interesting to see if this makes any real difference to the noise levels over Brentford and Syon.Planes taking part in the trial will be slightly higher than normal by an amount that's dependent on how far they are from the airport.As a rule of thumb, the difference is about 20 feet per mile. Over Syon, which is 5 miles from the runway, they will be about 100 feet higher than before, roughly 1,600 feet overhead instead of 1,500 feet.
Dave Robertson ● 3650d