DME Arc - FAA interpretation

Question 1

What is a DME arc?

Answer 1

a procedure in which an aircraft maintains a constant distance from a VOR/DME station while flying a curved path around it

Question 2

How can you teach this?

Answer 2

Practice a non-published DME arc: “17 DME arc 210 radial outbound and 180 radial inbound”

Question 3

What are the steps?

Answer 3

1) Intercept 210 radial outbound
2) Make a 90* degree turn
3) Center CDI - fly the heading on the left or right side of the CDI
4) Recenter CDI

Question 4

Explain step 1 in detail: how do you intercept 210 radial outbound?

Answer 4

we fly the arc on nav 2:

Tune and identify the navaid

Put the radial on the top of the instrument when flying outbound

Note the DME milage readout

Question 5

Explain step 2 in detail: how do you make a 90* turn?

Answer 5

make a left turn with a .5 nm lead at 16.5 DME

Question 6

Explain step 3 in detail: Center the CDI - fly the heading on the left or right side of the CDI

Answer 6

center the CDI needle upon completion of the 90° turn to intercept the arc. The aircraft’s heading is found very near the left or right side

The readings at that side
location on the instrument give primary heading information while on the arc.

Question 7

Explain step 4 in detail: Recenter CDI

Answer 7

Recenter the CDI and note the new primary

heading indicated whenever the CDI gets 2°– 4° from center.

Question 8

How much airspace protection is afforded in the DME arc?

Answer 8

4 nm but we can’t deviate more than 1 nm

Question 9

How do you know if you’re left or right of groundtrack?

Answer 9

Use the DME readout as you would a CDI to determine whether you’re left or right