This is what the NOTAM says:

!FDC 4/1981 ZDC MD.. FI/T AIRWAY ZDC.
V170-214-433-445 ODESA INT, MD TO KERNO INT, MD NA. USE SUBSTITUTE
ROUTE.

This segment of the substitute route goes directly over the airway,
except it appears to have a different MEA. So, what's the point of
creating a whole new thing called a 'substitute route'? Why not just
issue a NOTAM amending the MEA?




Dave S wrote in
ink.net:

Did you check the notams?

Dave

Andrew Sarangan wrote:
These are shown on the LL enroute chart by little brown circles
connected by a line. The legend says "substitute route, see NOTAMs".
There are several originating from the DQO VOR near the Washington DC
area, but there could be others as well. I have never noticed these
before. Any ideas what they are?