← All explained questions · Supplemental · III — Airport & Seaplane Base Operations

A 'WIND-T' or 'TETRAHEDRON' on the airport indicates

Choices

the airport elevation.
Elevation is published, not on a wind T.
✓ the wind direction.correct
the device pivots so the small end (tetrahedron) or vertical of the T points INTO the wind (i.e., the runway in use is into the wind, parallel to the indicator's pointing direction). Wind direction indicators on the field: wind sock (most common, blows away from wind, larger end with the wind), tetrahedron (small end points into wind), wind T (vertical bar points into the wind). Use these to determine the active runway at non-towered fields. Always confirm with CTAF traffic announcements.
the runway numbers.
Runway numbers are painted on the runway.
where to park.
Parking is indicated by other signs.

Why

the device pivots so the small end (tetrahedron) or vertical of the T points INTO the wind (i.e., the runway in use is into the wind, parallel to the indicator's pointing direction). Wind direction indicators on the field: wind sock (most common, blows away from wind, larger end with the wind), tetrahedron (small end points into wind), wind T (vertical bar points into the wind). Use these to determine the active runway at non-towered fields. Always confirm with CTAF traffic announcements.

FAA source: AIM 4-1-9, AC 150/5210-5; AIM 4-1-9 Traffic Advisory Practicesbrowse the reference library →

Covered in Supplemental · III — Airport & Seaplane Base Operations — study the lessons free, then practice with grading and mastery tracking.

Original study question written for this course — representative of FAA knowledge-test topics, not an actual current FAA exam question.