FAA Aircraft Dispatcher (ADX)Navigation and ATCEasy
A dispatcher notes that a proposed route between two city pairs is listed as a Preferred IFR Route in the Chart Supplement. What is the primary purpose of Preferred IFR Routes?
- ATo guarantee the shortest possible flight time between two airports
- BTo designate mandatory holding patterns for high-density terminal areas
- CTo eliminate the need for filing an alternate airport
- DTo minimize route delays and distribute traffic flow efficiently between busy terminals
Show answer & explanationAnswer & explanation
Correct answer: D. To minimize route delays and distribute traffic flow efficiently between busy terminals
Preferred IFR Routes are established between high-density terminals to increase system efficiency and reduce ATC coordination workload by distributing traffic along established corridors. They are not necessarily the shortest routes but are designed for efficient traffic flow.
Why the other options are wrong
- A. Preferred routes are chosen for traffic flow efficiency, not necessarily shortest distance.
- B. Preferred routes do not mandate holding patterns.
- C. Alternate airport requirements are governed separately by weather minimums, not route selection.
Preferred IFR Routes
Routes established between busier airports to standardize traffic flow, minimize delays, and simplify ATC coordination; published in the Chart Supplement.
- Found in the Chart Supplement (formerly A/FD)
- Not always the shortest route, but the most efficient for traffic flow
- Filing a preferred route reduces likelihood of reroute by ATC
- Divided into low altitude and high altitude preferred routes
Memory trick: 'Preferred = Predictable flow' — smooth traffic, not necessarily short