Non - ILS Approach - One Engine Inoperative
Engine out maneuvering prior to and after the final approach fix with one engine inoperative is the same as an all engine non-ILS approach.
Procedure Turn and Initial Approach
The procedure turn size is determined by the ground speed at the IAF.
Cross the IAF at flaps 5 and flaps 5 maneuvering airspeed and monitor the
procedure turn using the map to assure the airplane remains within protected
airspace. The depicted procedure turn, or holding pattern in lieu of procedure turn,
complies with approach airspace limits.
Note: If the fix is crossed at an excessively high ground speed, the procedure turn protected airspace may be exceeded.
If a complete arrival procedure has been selected via the CDU, the initial approach phase may be completed using LNAV and VNAV path, or other appropriate modes. Ensure the LEGS page sequences, altitude restrictions and map display reflects the air traffic clearance. Last minute air traffic changes or constraints may be managed by appropriate use of the MCP heading and altitude selectors. Updating the LEGS page sequencing should be accomplished only as time permits.
Vertical Path Construction
This section describes typical final approach vertical profile (path) construction criteria as they relate to flying instrument approaches using VNAV. This information may also be useful to pilots who wish to fly the vertical path using V/S.
Where there is a glide path (GP) angle coded in the navigation database, the FMC builds the descent path upward and back in the direction of the FAF by starting at the location of the missed approach waypoint (MAP) and its associated altitude constraint. The FMC calculates this path using the coded GP angle, also called the vertical angle. The MAP is normally shown on the LEGS page as a RWxx or MXxx waypoint. In some cases a named waypoint is used as the MAP. A GP angle is coded in the navigation database for nearly all approach procedures. Approaches identified as circling only do not have a GP angle.
This GP angle is normally defined by the state authority responsible for the approach procedure and provides a continuous descent at a constant flight path angle for a final approach path that complies with minimum altitudes at intermediate step down fixes. The typical GP angle is approximately 3.00°, but can vary from 2.75° to 3.77°.
The projection of the vertical path upward and back toward the FAF along this coded GP angle stops at the next higher limiting altitude in the vertical profile. This limiting altitude is the more restrictive of the following:
.
the “At” altitude on the constrained waypoint preceding the MAP
.
the crossing altitude on the next “at or above” constrained waypoint
preceding the MAP
.
the speed transition or the speed restriction altitude, whichever is lower
.
cruise altitude.
The following examples show typical VNAV final approach paths where there is a GP angle in the navigation database. The first example shows an RWxx missed approach waypoint. The second example below shows the VNAV final approach path where there is a missed approach waypoint prior to the runway. Note that in the second case the projected path crosses the runway threshold at approximately 50 feet. VNAV guidance is level flight, however, when the airplane passes the missed approach point. Both examples are for “At” altitude constraints at the FAF.
Copyright . The Boeing Company. See title page for details.
October 31, 2003 FCT 757 (TM) 5.35
Crews can expect to see several other variations of approach path construction:
.
approaches where the FAF has an “at or above” waypoint altitude
constraint. The GP angle normally terminates at the FACF altitude
constraint or the cruise altitude, whichever is lower. When this type of
path is flown, the airplane passes above the FAF.
.
where there is more than one GP angle, such as for ILS approaches, the
airplane uses the GP angle for the active leg to define the VNAV approach
path. These types of paths are shown on the LEGS page as having two GP
angle values, one approaching the FAF, the second approaching the
runway (missed approach point).
Note: The coded GP angle is steeper than normal in temperatures warmer than ISA standard and is shallower than normal in temperatures colder than ISA standard.
Copyright . The Boeing Company. See title page for details.
October 31, 2003 FCT 757 (TM) 5.37
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