HIGH ALTITUDE APPROACH
Reference: NIFM, Chapter 29; AFM 5137.
Instrument Approach Procedure (IAP) charts are divided into two categories: high
altitude and low altitude. A high altitude instrument approach enables an aircraft to
transition from the high altitude structure to a position on the final approach course for
High Altitude Instrument approaches are routinely executed by high performance
military aircraft into military aerodromes for the following reasons: to maintain
efficient fuel consumption, to maintain higher TAS, and to avoid low altitude weather
until closer to the destination.
The procedures used to execute a High Altitude Instrument approach combine the
penetration pattern first learned in the Basic Instruments Stage with Instrument
Approach Procedures learned in the Radio Instruments Stage (typically a Teardrop or
Arcing approach). For this reason, High Altitude approaches normally require higher
rates of descent and indicated airspeeds than Low Altitude approaches until the
transition to BAC. Once the aircraft is in BAC, procedures for both High and Low
Altitude Instrument approaches are the same.
Inbound to the IAF, complete the Penetration Checklist:
Oxygen . . . 100%.
Fuel state . . . check.
Defog . . . as required.
At the IAF, execute the 6 Ts:
TIME not required; time of commencing approach is not reported.
TURN turn in the shortest direction to parallel the course.
The penetration course is depicted on high altitude IAP charts by a
bolddotted track. Figure 715.
7-24 INSTRUMENT NAVIGATION