JO 7110.65 — Air Traffic Control
JO 7110.65 5-13-4
ENTRY OF REPORTED ALTITUDE
This reproduces published FAA reference text for study. It does not replace the current official FAA publication or regulation.
Whenever Mode C altitude information is either not available or is unreliable, enter reported altitudes into the computer as follows:
NOTE-
Altitude updates are required to assure maximum accuracy in applying slant range correction formulas.
When an aircraft reaches the assigned altitude.
When an aircraft at an assigned altitude is issued a clearance to climb or descend.
A minimum of each 10,000 feet during climb to or descent from FL 180 and above.
Retrieved from ecfr.gov on July 20, 2026.