Navigation and Route Planning Flashcards

What is the meaning of 'Q-routes' in the US National Airspace System and at what altitude band do they exist?

Answer: RNAV routes in the high-altitude enroute structure, from FL180 to FL450, serving as the RNAV equivalent of Jet Routes

Q-routes are high-altitude RNAV routes (FL180–FL450) that supplement Jet Routes for RNAV-equipped aircraft, offering more direct routings.

A dispatcher is computing the time enroute for a leg of 450 NM with a planned TAS of 300 knots and a forecast headwind component of 50 knots. What is the estimated ground speed and time for the leg?

Answer: Ground speed 250 kt; time 1 hour 48 minutes

GS = TAS − headwind = 300 − 50 = 250 kt; time = 450 ÷ 250 = 1.8 hr = 1 hour 48 minutes.

When dispatching a flight under Part 121, what is the regulatory requirement regarding the dispatcher's authority to release a flight into known or forecast severe icing conditions?

Answer: The flight may not be released if the aircraft is not certificated and equipped for the icing conditions known or forecast along the route

Under Part 121, dispatchers cannot release a flight into conditions for which the aircraft is not certificated and equipped, including known or forecast severe icing.

What is 'course deviation' in the context of route monitoring, and what action should a dispatcher take when notified of significant course deviation?

Answer: Any departure from the planned route; the dispatcher should assess the cause, evaluate fuel and alternates, and issue a revised ATC clearance or amended dispatch release if needed

Under Part 121, the dispatcher shares authority and responsibility; significant course deviations require assessment of fuel, weather, and possible route amendments.

What is the purpose of the North Atlantic Track System (NAT HLA) in dispatcher route planning for transatlantic flights?

Answer: To organize traffic flow across the Atlantic into organized tracks that take advantage of favorable winds, updated daily based on weather

The NAT track system provides dynamically adjusted organized tracks to exploit the jet stream and manage transatlantic traffic separation, with new tracks published each day.

When a route segment passes through a Special Use Airspace (SUA) such as a Military Operations Area (MOA), what must a dispatcher verify before releasing the flight?

Answer: Whether the MOA is active during the planned time of flight, and if so, whether an alternative route or altitude avoids the active SUA

Dispatchers must check NOTAM and scheduling information to determine SUA activity and plan around active restricted airspace when necessary.

What does 'drift-down procedure' mean in route planning for twin-engine transport aircraft?

Answer: The planned descent path and route an aircraft follows after an engine failure at cruise altitude, allowing it to glide down to a safe enroute altitude while avoiding terrain

Drift-down is the single-engine descent profile used after engine failure at altitude; dispatchers must verify that the drift-down path clears terrain and reaches a safe altitude.