Engine Failure On Final Approach
If an engine failure should occur on final approach with the flaps in the landing position, adequate thrust is available to maintain the approach profile using landing flaps, if desired.
A landing using flaps 25 or 30 might be preferable in some circumstances, especially if the failure occurs on short final or landing on runways where stopping distance is critical.
The ability to continue the approach with such a failure in Category III operations may also be a factor. If the approach is continued at flaps 25 or 30, advance the thrust to maintain the appropriate speed.
If a go-around is required, follow the normal missed approach/go-around procedures, retracting the flaps to 20. Adequate performance is available at flaps
20. Subsequent flap retraction should be made at a safe altitude in level flight or a shallow climb.
It is usually preferable to continue the approach using flaps 20. This provides a better thrust margin, less thrust asymmetry and improved go-around capability. If the decision is made to reduce the flap setting, increase thrust to attain flaps 20 speed. Speed should be increased to 15 knots over the previously set flaps 25 or 30 VREF. This is equal to at least VREF for flaps 20.
If a go-around is required with flaps set at 20, maintain the additional 15 knots, select flaps 5 and continue the usual engine inoperative go-around. The decision to continue the approach at normal landing flaps, to retract the flaps to 20 or execute a go-around is a decision that should be made immediately.
Non - ILS Instrument Approaches
Non-ILS approaches are defined as:
.
RNAV approach - an instrument approach procedure that relies on aircraft
area navigation equipment for navigational guidance. The FMS on
Boeing airplanes is FAA-certified RNAV equipment that provides lateral
and vertical guidance referenced from an FMS position. The FMS uses
multiple sensors (as installed) for position updating to include GPS,
DME-DME, VOR-DME, LOC-GPS, and IRS.
.
GPS approach - an approach designed for use by airplanes using
stand-alone GPS receivers as the primary means of navigation guidance.
However, Boeing airplanes using FMS as the primary means of
navigational guidance, have been approved by the FAA to fly GPS
approaches provided an RNP of 0.3 or smaller is used.
Note: A manual FMC entry of 0.3 RNP is required if not automatically provided.
.
VOR approach
.
NDB approach
.
LOC, LOC-BC, LDA, SDF, IGS, TACAN, or similar approaches.
Non-ILS approaches are normally flown using VNAV or V/S pitch modes. Recommended roll modes are provided in the applicable Operations Manual procedure.
Non - ILS Instrument Approaches - General
Over the past several decades there have been a number of CFIT and unstabilized approach incidents and accidents associated with non-precision (non-ILS) approaches and landings. Many of these could be prevented by the use of constant angle approach methods. Traditional methods of flying non-ILS approaches involve setting a vertical speed on final approach, leveling off at step-down altitudes (if applicable) and at MDA(H), followed by a transition to a visual final approach segment and landing. These traditional methods involve changing the flight path at low altitudes and are not similar to methods for flying ILS approaches. Further, these traditional methods often require of the crew a higher level of skill, judgment and training than the typical ILS approach.
The following sections describe methods for flying non-ILS constant angle approaches. If used, these methods provide a constant angle approach, which reduces exposure to crew error and CFIT accidents. These methods also make it much easier for the crew to achieve a stabilized approach to a landing once suitable visual reference to the runway environment has been established.
A typical Instrument Approach using VNAV or V/S, as illustrated, assumes all preparations for the approach; such as review of the approach procedure and setting of minima and radio tuning have been completed. The procedures illustrated focuses generally on crew actions and avionics systems information. The flight pattern may be modified to suit local traffic and air traffic requirements.
The following discussions assume a straight-in instrument approach is being flown. A circling approach may be flown following an instrument approach using VNAV or V/S provided the MCP altitude is set in accordance with the circling approach procedure.
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