Definition
Military Training Routes (MTRs) flown under Instrument Flight Rules, designated 'IR' followed by a route number, used by military aircraft to conduct low-altitude, high-speed training in weather conditions where visual separation cannot be relied upon. IR routes are flown in accordance with IFR procedures regardless of actual weather, and may include segments above 1,500 feet AGL.
Plain English
These are special low-level corridors set aside for military aircraft to practice fast flying using their instruments. They are labeled with 'IR' and a number, and the pilots follow them whether the weather is clear or not.
Context Anchor
Seen during flight planning and on aeronautical charts as routes labeled “IR” followed by route numbers.
Derivation
IR' stands for 'IFR Route.' The 'IFR' prefix distinguishes these from VR (VFR) routes, signaling that the military aircraft will be flying on instruments and may not be looking outside for traffic.
Why Pilots Care
Civilian pilots must identify these routes to avoid conflicts with high-speed military traffic that may not be in contact with ATC.
Grounding Statement
Picture a military aircraft following a published practice path across country while flying by instrument procedures.
Intuition Check
Do not assume an IFR Military Training Route is closed airspace. It is a published military training path; other aircraft may be allowed nearby or across it, but fast military traffic may be present.
Example Sentence 1
While planning a cross-country, the pilot noticed her route crossed IR-104 and called Flight Service to check if the route was active that afternoon.
Example Sentence 2
VFR traffic should remain clear of IFR Military Training Routes during low-level operations.