How many ADCs are required for RVSM?

How many ADCs are required for RVSM?

• A. 1
• B. 2
• C. 3
• D. 0

Answer: (B)

Redundancy in air data is required for RVSM. The altitude-keeping system must rely on two independent air data measurement channels, each with its own air data computer (ADC). This setup lets the aircraft cross-check altitude information and detect any single-sensor failure or drift. If one ADC provides faulty data, the remaining, independently sourced data can maintain accurate altitude and trigger a fault alert if there’s a discrepancy beyond limits. Because RVSM reduces vertical separation to a tight 1000 feet, this dual-ADC arrangement is the minimum needed to ensure reliable, verifiable altitude readings. So, two ADCs are required.

Redundancy in air data is required for RVSM. The altitude-keeping system must rely on two independent air data measurement channels, each with its own air data computer (ADC). This setup lets the aircraft cross-check altitude information and detect any single-sensor failure or drift. If one ADC provides faulty data, the remaining, independently sourced data can maintain accurate altitude and trigger a fault alert if there’s a discrepancy beyond limits. Because RVSM reduces vertical separation to a tight 1000 feet, this dual-ADC arrangement is the minimum needed to ensure reliable, verifiable altitude readings.

So, two ADCs are required.