In the blocking example for a Byerley departure, what altitude block is requested?

• A. Ten thousand and above
• B. Seven thousand and above
• C. Five thousand and below
• D. Three thousand and below

Answer: (C)

Altitude blocks on IFR departures are vertical restrictions that keep traffic within a defined altitude range to manage separation in the early part of a procedure.

In the Byerley departure blocking example, the control authority requests a block that caps traffic at five thousand feet, meaning aircraft must remain at or below 5,000 feet on that segment. This ceiling helps prevent conflicts with other streams of traffic and allows for orderly, protected climbs as you transition to the en route structure.

The other options would impose higher ceilings or a much lower restriction that isn’t used in this example. A block of 10,000 feet and above or 7,000 feet and above would let traffic climb too high too early, risking conflicts on the initial departure path. A block of three thousand feet and below would be overly restrictive and isn’t the stated configuration for this scenario.