Morning
Heathrow's runways are 1400m apart. Whilst it would be entirely possible to operate ICAO standard Independent or Dependant parallel approach operations, the ATC authority here has not applied the necessary ICAO safeguards. There are a number of reasons.
The most significant one is staffing: ICAO parallel ops would require a second Final Director and a Monitoring controller for each approach - that's 3 more control positions, which requires at least 4 extra staff per watch. As I said in a previous post, we just cannot get the staff to do that. Also, as the Government currently limits the time at which multiple approaches can be routinely made to 06:00-07:00 each morning the benefit gained in terms of capacity doesn't justify the additional cost to the system - we would have many additional controllers (assuming we could train them) standing around and only used between 06:00 and 07:00.
When (if) full Mixed-mode operations are introduced throughout the day, the cost/benefit equation will justify the staffing issue because the additional staff will be constantly in use and the financial benefit to the system will be significant (about 10% increase in capacity).
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