Question: When flying under IFR in designated mountainous areas, en route obstacle clearance is 2,000 feet. Are there any exceptions to this rule?
Answer: Yes. Obstacle clearance may be reduced to not less than 1,500 feet above terrain in designated mountainous areas of the eastern United States, Hawaii, and Puerto Rico. In the western United States, obstacle clearance may be reduced to not less than 1,700 feet above terrain. These reduced terrain clearance minimums are granted only if certain conditions are met. For more information on this topic, see Chapter 3 of the Instrument Procedures Handbook.