FAA Aircraft Dispatcher (ADX)Navigation and ATCHard
A dispatcher reviewing a route sees the segment identifier 'J80' on an enroute high-altitude chart. What does this designation indicate about the route?
- AIt is a military training route not available for civilian IFR use
- BIt is an RNAV route usable only by GPS-equipped aircraft
- CIt is a low-altitude Victor airway used below 18,000 feet MSL
- DIt is a jet route used at or above 18,000 feet MSL, based on VOR/VORTAC navigation
Show answer & explanationAnswer & explanation
Correct answer: D. It is a jet route used at or above 18,000 feet MSL, based on VOR/VORTAC navigation
Routes designated with a 'J' prefix (e.g., J80) are jet routes, which exist at and above 18,000 feet MSL up to FL450 and are based on VOR/VORTAC navigation aids, similar to Victor airways but at high altitude. Victor airways use a 'V' prefix and exist below 18,000 feet MSL.
Why the other options are wrong
- A. Military training routes use IR/VR designators, unrelated to J-route naming.
- B. RNAV routes use Q or T prefixes, not J.
- C. Victor airways (V-prefix) are the low-altitude equivalent, not jet routes.
Jet Routes (J-Routes)
High-altitude airways designated with a 'J' prefix, existing at and above 18,000 feet MSL up to FL450, based on VOR/VORTAC navigation aids.
- J-routes = high-altitude, VOR/VORTAC based, 18,000 ft MSL to FL450
- V-routes (Victor airways) = low-altitude, below 18,000 ft MSL
- Q-routes = RNAV high-altitude routes
- T-routes = RNAV low-altitude routes
Memory trick: 'J for Jet, up high, VOR guide'