AIM ¶ 3-5-2 — Military Training Routes
AIM 3-5-2 explains IR and VR Military Training Routes, charting, speeds above 250 kt, and how pilots get MTR briefings from Flight Service.
Military Training Routes (MTRs) are jointly developed by the FAA and DoD so the military can practice low-altitude, high-speed tactics — typically below 10,000 feet MSL at speeds above 250 knots. As a civilian pilot, you need to know how to identify them, find them on charts, and avoid traffic conflicts.
There are two types:
- IR (IFR Military Training Route): Flown under IFR regardless of weather.
- VR (VFR Military Training Route): Flown under VFR; requires 5 SM flight visibility and a ceiling no less than 3,000 ft AGL.
Route identification by numbering:
- Four digits (e.g., IR1206, VR1207) = no segment above 1,500 ft AGL.
- Three digits (e.g., IR206, VR207) = one or more segments above 1,500 ft AGL.
- Letter suffixes (e.g., IR008A) indicate alternate routes.
Charting: IR and VR routes above 1,500 ft AGL appear on IFR Enroute Low Altitude Charts; VFR Sectionals depict MTRs and may show Special Military Activity Routes (SMARs) for unmanned aircraft operations. Detailed info is in the DoD FLIP AP/1B.
Nonparticipating aircraft aren't prohibited from MTRs, but extreme vigilance is required. Within 100 NM of an MTR, contact Flight Service for current activity, altitudes, and route width — which can extend several miles either side of centerline.
Five FAA-written-style questions. Instant explanations, every answer cites its source — no account needed.
You are flying VFR in Class E airspace at 8,500 feet MSL during the day. What are your minimum visibility and cloud clearance requirements?