CH 12 Final Approach Flashcards
Final Approach Components
final approach fix (FAF), stepdown fixes, visual descent point (VDP), missed approach point (MAP), minimum descent altitude (MDA) and decision height/decision altitude (DH/DA). The first four can be defined by a NAVAID, a waypoint, crossing radials of two NAVAIDs, or a radial and DME
optimum final approach course length
5 miles but may be as long as 10 miles
Stepdown Fixes
Some non-precision approaches may have one or more stepdown fixes between the FAF and the MAP. These fixes are normally included to avoid an obstacle inside the FAF.
VDP
a point in a non-precision straight-in approach procedure from which a normal descent (approximately 3°) from the MDA to the runway touchdown point may be commenced, provided visual reference with the runway environment is established
multi-facility approaches, the depicted VDP will be for
lowest MDA published
VDP calculation with no DME present
take 10% of HAT in seconds then take distance to RWY and groundspeed to calculate VDP Time
when the FAF is the NAVAID for the approach, a course change of up how degrees are possible
30 degrees
Calculate VVI for 3 degree GS
Groundspeed x 10 / 2
When is timing to MAP required
when the final approach does not terminate at a published fix
Runway Environment
-threshold, threshold markings or threshold lights
-runway end identifier lights
-touchdown zone, touchdown zone markings, or touchdown zone lights
-runway or runway markings
runway lights
-visual approach slope indicator
Non-radar Approaches
ILS, VOR, TAC, NDB, RNAV/GPS and MLS
ILS Required Components
Glide Slope, Localizer and outer marker (can be replaced by DME, other NAVIAD, RADIAL or radar)
Transition to the ILS Localizer Course
radar vectors or a published approach procedure
Glide Slope usable range
10 miles
Localizer usable range
18 miles within 10 degrees