AIM 

4/20/23 

FIG 9

−

1

−

4 

Helicopter Route Charts 

b.  IFR Navigation Charts. 

1.  IFR En Route Low Altitude Charts (Conterminous U.S. and Alaska). 

En route low altitude charts 

provide aeronautical information for navigation under IFR conditions below 18,000 feet MSL. This four

−

color 

chart series includes airways; limits of controlled airspace; VHF NAVAIDs with frequency, identification, 

channel, geographic coordinates; airports with terminal air/ground communications; minimum en route and 

obstruction clearance altitudes; airway distances; reporting points; special use airspace; and military training 

routes. Scales vary from 1 inch = 5nm to 1 inch = 20 nm. 50 x 20 inches folded to 5 x 10 inches. Charts revised 

every 56 days. 

Area charts

 show congested terminal areas at a large scale. They are included with subscriptions 

to any conterminous U.S. Set Low (Full set, East or West sets). (See FIG 9

−

1

−

5 and FIG 9

−

1

−

6.) 

9

−

1

−

4 

Types of Charts Available