3 Different ILS Approaches
Dependent Parallel Approach
- RWY's centerlines must be separated by
at least 2.500 ft
- A/C must be separate diagonally by
a minimum of 1-1/2 nm.
- A/C must be separated by 2nm diagonally for RWY centerlines separated between
4,300ft and 9,000ft – WITHOUT a final monitoring by ATC
- separation is provided by radar
> NTZ → No Transgression Zone
> NOZ → Normal Operating Zone
Simultaneous Parallel Approach
- RWY centerline separation between 4.300 and 9.000ft WITH a final monitor ATC.
(ATC eliminates the need for staggered appr)
- no diagonal separation required
final monitor ATC advises pilots IF deviating from the LOC course.
Triple Simultaneous Approaches
- are authorized if RWY CTL's are separated by at least 5.000 ft and are below 1000 ft MSL
IF ABOVE 1000FT MSL
- ASR monitoring or high update radar with final monitoring aid is required
Simultaneous Close (indep.) Parallel Approach PRM
Precision Runway Monitor
- for parallel RWY's with a separation between 3.400 ft and 4.300 ft
The PRM system contains a high-update radar
with a one second interval
position and velocity is updated every second
- Appr requires an approriate system and controller as well as two tower frequencies
- special crew training is required for P121/135 (FAA)
