4/20/23 

AIM 

adherence to VFR rules must be exercised at all times. Further, when operating beneath Class B airspace, 

communications must be established and maintained between your aircraft and any control tower while transiting 

the Class B, Class C, and Class D surface areas of those airports under Class B airspace. 

b.  VFR Corridors. 

1. 

The design of a few of the first Class B airspace areas provided a corridor for the passage of uncontrolled 

traffic. A VFR corridor is defined as airspace through Class B airspace, with defined vertical and lateral 

boundaries, in which aircraft may operate without an ATC clearance or communication with air traffic control. 

2. 

These corridors are, in effect, a “hole” through Class B airspace. (See FIG 3

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2.) A classic example 

would be the corridor through the Los Angeles Class B airspace, which has been subsequently changed to Special 

Flight Rules airspace (SFR). A corridor is surrounded on all sides by Class B airspace and does not extend down 

to the surface like a VFR Flyway. Because of their finite lateral and vertical limits, and the volume of VFR traffic 

using a corridor, extreme caution and vigilance must be exercised. 

FIG 3

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Class B Airspace 

3. 

Because of the heavy traffic volume and the procedures necessary to efficiently manage the flow of 

traffic, it has not been possible to incorporate VFR corridors in the development or modifications of Class B 

airspace in recent years. 

c.  Class B Airspace VFR Transition Routes. 

1. 

To accommodate VFR traffic through certain Class B airspace, such as Seattle, Phoenix and Los Angeles, 

Class B Airspace VFR Transition Routes were developed. A Class B Airspace VFR Transition Route is defined 

as a specific flight course depicted on a TAC for transiting a specific Class B airspace. These routes include 

specific ATC-assigned altitudes, and pilots must obtain an ATC clearance prior to entering Class B airspace on 

the route. 

2. 

These routes, as depicted in FIG 3

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3, are designed to show the pilot where to position the aircraft 

outside of, or clear of, the Class B airspace where an ATC clearance can normally be expected with minimal or 

no delay. Until ATC authorization is received, pilots must remain clear of Class B airspace. On initial contact, 

pilots should advise ATC of their position, altitude, route name desired, and direction of flight. After a clearance 

is received, pilots must fly the route as depicted and, most importantly, adhere to ATC instructions. 

Other Airspace Areas 

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