Definition
MVA (Minimum Vectoring Altitude) is the lowest altitude, expressed in feet above mean sea level, at which an air traffic controller may legally vector an aircraft under radar control. It is established for each sector within a controller's airspace and provides required obstacle clearance — generally 1,000 feet above the highest obstacle in non-mountainous areas and 2,000 feet in designated mountainous areas — while also accounting for radar and communication coverage. MVAs are depicted on the controller's radar display but are not published on standard pilot charts. MIA (Minimum IFR Altitude) is the lowest altitude at which IFR operations may be conducted, as prescribed in 14 CFR Part 91. MIAs include published minimum en route altitudes (MEA), minimum obstruction clearance altitudes (MOCA), and other charted minimum altitudes that appear on instrument charts available to the pilot.
Plain English
Two related 'how low can we go under IFR' altitudes. MVA is the lowest altitude a controller is allowed to send you to when they're guiding you on radar. MIA is the lowest altitude you're allowed to fly under instrument rules, based on the minimums printed on your charts.
Context Anchor
Seen in instrument procedure and ATC discussions, including visual approach situations where an IFR aircraft may be kept at or above a minimum altitude until it can proceed visually.
Derivation
Vectoring comes from 'vector,' a heading or direction given by ATC. So a Minimum Vectoring Altitude is the lowest altitude a controller can use while directing your heading on radar. IFR stands for Instrument Flight Rules, so a Minimum IFR Altitude is the lowest altitude allowed while operating under those rules.
Why Pilots Care
Tells the pilot the floor below which ATC will not vector the aircraft, protecting against terrain and obstacles during the transition to visual flight.
Intuition Check
Do not read MVA/MIA as a suggested altitude. In IFR operations, it is a minimum safety altitude used to protect against terrain and obstacles.
Example Sentence 1
ATC cleared us down to 2,400 feet on the vector to final, which was below any altitude on our chart but still at or above the MVA for that sector.
Example Sentence 2
The controller kept us at the published MIA until we reported the runway in sight.