This is great follow-up question to a previous post, “Can you use a q-route below FL180?”. The question came to me after posting a link to that post on my Twitter profile.

So what the heck is a Q-route?

Well. There are primarily three types of airways:

1) VOR Federal airways – This is the airway system that most pilots are most familar with. This includes your typical low alitudes “V” airways and the high-altitude “J” routes.

2) Colored Federal Airways – There are still 49 of these airways still in existence. LF and MF and they can be found mostly in Alaska. They are designated by their color names Amber, Blue, Green or Red and then either a one or two digit number, i.e. “A 7”

3) RNAV airways – This is the latest and greatest route system found in our nation’s airspace. The foundation of the RNAV route system started in 2000 with industry operators requesting the FAA to increase the use of RNAV to help navigate the nation’s airspace. The advantages of the RNAV system? Reduced mileage, reduction of conflicts between routes, and additional routes within the same airspace.

There are two types of RNAV routes:

1) Q-routes (high) are available for use by RNAV equipped aircraft between 18,000 feet MSL and FL 450 inclusive. Q-routes are depicted on Enroute High Altitude Charts.

1) T-routes (low) are available for use by RNAV equipped aircraft from 1,200 feet above the surface (or in some instances higher) up to but not including 18,000 feet MSL. T-routes are depicted on Enroute Low Altitude Charts.

So now a good follow-up question would be, “Can you file and use a Q-route below FL180?” and you see, we the staff at askacfi.com have thought ahead and already answered that one for you and you can read the answer to that question here.