In a DME arc procedure, what should you do after completing the first 90-degree turn?

• A. Leave CDI alone
• B. Center the CDI, then twist 10
• C. Center the CDI, then twist 15
• D. Center the CDI, then twist 5

Answer: (B)

In a DME arc, you’re flying a curved path around a VOR/DME while keeping a constant distance from the VOR. After finishing the first 90-degree turn, re-center the CDI so the indicator is neutral again, then twist the course selector by 10 degrees. Centering the CDI resets your deviation to zero, which helps you accurately track the arc rather than chasing a biased indication from the previous leg. The 10-degree twist biases the OBS toward the proper arc-tangent direction for the next segment, helping you stay on the intended curved path and maintain the correct DME distance. Leaving the CDI uncentered or twisting by a significantly different amount would misalign you from the arc and lead to drift off course.