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I have been reading about Mumbai Airport (CSIA) (IATA: BOM ICAO: VABB). On it they mention:

The airport has two intersecting runways. Both runways have been upgraded to Code F, which means they can accommodate larger aircraft like the Airbus A380. Following a presentation in March 2011 by UK’s air traffic service provider NATS on how the capacity of the airport can be increased, MIAL set a target of 48 aircraft movements an hour in an effort to reduce congestion at the airport. Both runways were operated simultaneously especially during peak hours to try and attain this target.MIAL scrapped simultaneous Cross-runway flight operations in mid-2013 after it found that single runway operations were more effective for increasing Aircraft movements per hour. Runway 14/32 is now used only when the main runway is unavailable due to maintenance or other reasons. The construction of new rapid exit taxiways helped in increasing flight handling capacity from 32 movements per hour to 44 in 2012.

Can somebody share what are these rapid exit taxiways and how do they help to increase flight handling capacity ?

I did see the OSM page and was able to get this -

CSIA map here

Maybe that could help in explaining what is being told to us. Have given/shared a more detailed diagram that I could find from OSM.

CSIA in more detail

Also it would be nice if a sketch/diagram of how these rapid taxiways are laid on CSIA or failing that a diagram of any airport having similar/more/less number of rapid exit taxiways would be good too in order to understand how they work.

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See this related question.

Rapid exit taxiways (or high speed exits) enable aircraft to leave the runway at speeds up to 50 or 60 kts depending on the runway and aircraft type (50 kts even in wet conditions).

They have a long, constant radius rather than a 90 degree turn.

You might find this FAA presentation useful.

enter image description here Source: airlinepilots.com forum.

The purpose is to enable a landing aircraft to vacate the runway more quickly without having to slow down to "normal" taxi speeds. A large aircraft like a 777 might need to slow to 10 or 15 knots to take a right angle turn. This would mean spending longer on the runway slowing down to that speed.

Since the aircraft next on the approach cannot land until the runway is clear, this enables closer spacing of landing aircraft.

Aircraft type, airport restrictions, operator standard procedures and weather can all impact what "high speed" means but it is always faster than the 90 degree turn.

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  • $\begingroup$ How does the speed for 150° turns compare with 90° turns? Can it potentially cause more congestion on the taxiways while reducing congestion on the runway(s)? $\endgroup$ – gsnedders Jan 3 '17 at 17:20
  • $\begingroup$ @gsnedders Think of it like a highway. You can exit a highway onto a curved ramp at 80 mph, no problem. Try doing that with a sharp 90 degree turn and you're going to have a bad day. The same is true when 'driving' an airplane on the ground. As far as congestion on the taxiway, that's not really a big concern. Many planes can occupy the same taxiway, but only one can occupy the runway at a time (with the exception of "line up and wait.") $\endgroup$ – reirab Jan 3 '17 at 19:10

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