Above Victor airway 154 on the IFR enroute low altitude chart, there is a grey zigzag line between Dublin VORTAC and LOTTS intersection.
What does the gray zigzag over the segment indicate?
Credit: SkyVector
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Sign up to join this communityAbove Victor airway 154 on the IFR enroute low altitude chart, there is a grey zigzag line between Dublin VORTAC and LOTTS intersection.
What does the gray zigzag over the segment indicate?
Credit: SkyVector
According to the “Airspace Information” section of FAA Aeronautical Chart User’s Guide, it is a low-altitude unusable route. The high-altitude flavor is similar in shape with a smaller amplitude.
See also page 62 of the Guide PDF, if you prefer.
In this particular case, observe the overprint on 110 in the compass rose surrounding DBN, which indicates abnormal status. The Airport/Facility Directory entry for Dublin VORTAC (as of the 31 MAR 2016 publication) reads, with added emphasis:
DUBLIN N32°33.81′ W82°49.80′ NOTAM FILE MCN.
(L) VORTAC 113.1 DBN Chan 78 276º 7.9 NM to W H 'Bud' Barron. 306/5W. HIWAS.
VOR portion unusable:
215°–285° byd 10 NM blo 3,500’
001°–139° byd 33 NM
001°–139° blo 5,000’
RCO 122.1R 122.6 113.1T (MACON RADIO)
Note that the DBN 110 radial falls within the 001-139° unusable range. Beyond LOTTS intersection, V154 is defined with reference to the Savannah VORTAC.