Approach MINIMA Weather Minimums

INSTRUMENT FLIGHT RULES WORKBOOK

CHAPTER THREE

position from which a descent to landing on the intended runway can be made at a normal rate of

descent using normal maneuvers. Circling minimums are only used in conjunction with

nonprecision approaches.

Height Above Touchdown (HAT) applies to precision and nonprecision straight-in

approaches. HAT indicates the height of the DH or MDA above the highest runway elevation in

the touchdown zone. It is an altitude expressed in AGL. The touchdown zone is the first 3000

feet of the duty runway.

*Answers:

1. Nonprecision

2. Precision

Height Above Airport (HAA) is also an AGL altitude, but it only applies to Circling maneuver

minima. HAA indicates the height of the MDA above the published airport elevation and affords

a minimum of 300 feet of obstruction clearance.

310. APPROACH MINIMAWEATHER MINIMUMS

Ceiling

Before the pilot of a single-piloted aircraft can accept an approach clearance (with the intention

to land), the weather at the airfield must be equal to or above the weather minimums published

for that approach. The ceiling is expressed in feet above the published airport elevation (AGL),

and is equal to or greater than the height of the associated DH or MDA. Ceiling values are

shown in parentheses.

Visibility

Visibility minimums for an approach are listed in one of three ways. The visibility value follows

the DH or MDA (i.e., 700/40 or 7001) and is expressed as Runway Visual Range (RVR),

Runway Visibility Value (RVV), or Prevailing Visibility (PV).

For straight-in approaches the visibility values will be either RVR, RVV, or PV. For circling

approaches, the value will always be PV. It should be noted that the visibility is separated from

the DH by a slant line (/) when it is RVR, and separated by a hyphen () when it is an RVV or

PV value.

RVR values are written in hundreds of feet. (An RVR value of 40 = 4000 feet.) RVV and PV

values are written in fractions of statute miles (i.e., 1/2, 3/4, 11/2, 2).

The ceiling and visibility values shown in parenthesis are to be used in flight planning. Review

again the Radar Instrument Approach Minimums Section.

INSTRUMENT APPROACH PROCEDURES 3-9