Gonzo:
Simultaneous approaches most certainly are possible. They most certainly are not 'against the law', whatever that means. What law do you think we'd be breaking?
ICAO 4444 section 6.7 - Simultaneous Parallel operations.
But on rereading this doc, it seems that the minimum 1500m runway separation limit only applied during bad weather. Otherwise, you can come down to 1000m, which seems pretty close.
But it does mean that LHR would have to stop parallel operations during any Sigmet. That is the Law. And if you think a recommendation is not a law, then think what a smart lawyer would say when viewing the smoldering wreckage.
Dave
I don't want to get into an argument about definitions, but are you saying that a stream of TEAM arrivals on 27L/27R at 2nm diagonal spacing can't reasonably be described as "simultaneous parallel approaches" ?
That is a Dependent Parallel Approach.
If the aircraft are to fly abeam each other, then this is an Independent Parallel Approach.
The spacing limits are obviously different, for the different types of airport and approach.
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