MLchartDataset catalogue

Off-route obstruction clearance altitude (OROCA)

Term · Aviation and air traffic control · MLC-T-AVN-000689

A published altitude which provides terrain and obstruction clearance with a 1,000 foot buffer in non-mountainous areas and a 2,000 foot buffer in designated mountainous areas within the United States, and a 3,000 foot buffer outside the US ADIZ. These altitudes are not assessed for NAVAID signal coverage, air traffic control surveillance, or communications coverage, and are published for general situational awareness, flight planning, and in-flight contingency use.

Table 1. Record
IdentifierMLC-T-AVN-000689
FieldAviation and air traffic control
AbbreviationOROCA
ReferencesFAA Pilot/Controller Glossary
Record as JSON
{
  "id": "MLC-T-AVN-000689",
  "term": "Off-route obstruction clearance altitude (OROCA)",
  "field": "Aviation and air traffic control",
  "definition": "A published altitude which provides terrain and obstruction clearance with a 1,000 foot buffer in non-mountainous areas and a 2,000 foot buffer in designated mountainous areas within the United States, and a 3,000 foot buffer outside the US ADIZ. These altitudes are not assessed for NAVAID signal coverage, air traffic control surveillance, or communications coverage, and are published for general situational awareness, flight planning, and in-flight contingency use.",
  "abbreviation": "OROCA",
  "references": [
    "FAA Pilot/Controller Glossary"
  ],
  "url": "https://mlchart.com/terminology/aviation/off-route-obstruction-clearance-altitude-oroca/"
}

Record 689 of 1,122 in Aviation and air traffic control terminology (MLC-0104). Request the full dataset.