Aeronautical Information Manual (AIM), page 169

Index   168 -- Page 169 -- 170

2. VFR Flyways are depicted on the reverse side
of some of the VFR Terminal Area Charts (TAC),
commonly referred to as Class B airspace charts. (See

FIG 3-5-1.) Eventually all TACs will include a VFR

Flyway Planning Chart. These charts identify VFR
flyways designed to help VFR pilots avoid major
controlled traffic flows. They may further depict
multiple VFR routings throughout the area which
may be used as an alternative to flight within Class B
airspace. The ground references provide a guide for
improved visual navigation. These routes are not
intended to discourage requests for VFR operations
within Class B airspace but are designed solely to
assist pilots in planning for flights under and around
busy Class B airspace without actually entering
Class B airspace.

3. It is very important to remember that these
suggested routes are not sterile of other traffic. The
entire Class B airspace, and the airspace underneath
it, may be heavily congested with many different
types of aircraft. Pilot 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 3-5-2.) A classic
example would be the corridor through the Los
Angeles Class B airspace, which has been subse-
quently 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 3-5-2

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 3-5-3, 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 3-5-7

Page 169 of the Aeronautical Information Manual (AIM.pdf)
AIM: Official Guide to Basic Flight Information and ATC Procedures

Index   168 -- Page 169 -- 170