Wind Corrections

INTERMEDIATE FLIGHT PREPARATION WORKBOOK

APPENDIX H

approach. The corrections below summarize landing data corrections required due to wind

effects.

Wind Corrections

In planning the landing, accounting for wind requires the wind direction and speed be known.

The headwind (or tailwind) and crosswind components can then be determined using Takeoff

and Landing Crosswind Chart in the PCL. Application of wind components to landing data is

discussed below.

Headwind

If advantage of a headwind is to be taken, use 50% of the steady headwind component when

determining flare and ground roll distances.

Tailwind

Apply 150% of the tailwind component to flare and ground roll distances.

Crosswind

When determining the crosswind component, enter the Wind Component Chart with the sum of

the steady wind value plus the gust increment. The maximum demonstrated crosswind for

takeoff and landing is 25 knots. Takeoff and landings in crosswinds greater than 25 knots are not

recommended.

Gusts

The gust increment is obtained from ground meteorological sources, usually the Control Tower.

It is the difference between the reported steady wind velocity and the reported peak gust velocity.

Increase the landing threshold speed and touchdown speed by 50% of the gust increment, not to

exceed a speed increase of 10 knots.

Go-Around Planning

The decision to go around should be made as early as possible, since jet engine acceleration time

is high and approach speeds are relatively close to touchdown speeds. This is of extreme

importance when one engine is inoperative, since the reduced thrust available and the limited

directional control under such circumstances may make a go-around impossible. A maximum

safe go-around %N1 setting can be read from the in-flight guide. Regardless of the aircraft

configuration (e.g., 1 or 2 engines operating), if the applicable go-around %N1 setting is not

exceeded and the aircraft is not slowed below the appropriate speed, VMCA will always be less

than or equal to the speed at which go-around is initiated. For a go-around, observe flap

retraction speeds. When the maximum landing weight is observed, a minimum 1-engine

inoperative climb gradient of 2.5% will be obtainable at VAC with the landing gear retracted. The

T-1A PERFORMANCE MANUAL EXTRACTS

H-9