1. At least 1 statute mile flight visibility for operations within Class B, Class C, Class D, and Class E surface
areas.
2. At least 1 statute mile ground visibility if taking off or landing. If ground visibility is not reported at that
airport, the flight visibility must be at least 1 statute mile.
3. The restrictions in subparagraphs 1 and 2 do not apply to helicopters. Helicopters must remain clear of
clouds and may operate in Class B, Class C, Class D, and Class E surface areas with less than 1 statute mile
visibility.
b. When a control tower is located within the Class B, Class C, or Class D surface area, requests for clearances
should be to the tower. In a Class E surface area, a clearance may be obtained from the nearest tower, FSS, or
center.
c. It is not necessary to file a complete flight plan with the request for clearance, but pilots should state their
intentions in sufficient detail to permit ATC to fit their flight into the traffic flow. The clearance will not contain
a specific altitude as the pilot must remain clear of clouds. The controller may require the pilot to fly at or below
a certain altitude due to other traffic, but the altitude specified will permit flight at or above the minimum safe
altitude. In addition, at radar locations, flights may be vectored if necessary for control purposes or on pilot
request.
NOTE-
The pilot is responsible for obstacle or terrain clearance.
REFERENCE-
14 CFR Section 91.119, Minimum safe altitudes: General.

d. Special VFR clearances are effective within Class B, Class C, Class D, and Class E surface areas only. ATC
does not provide separation after an aircraft leaves the Class B, Class C, Class D, or Class E surface area on a
special VFR clearance.
e. Special VFR operations by fixed-wing aircraft are prohibited in some Class B and Class C surface areas
due to the volume of IFR traffic. A list of these Class B and Class C surface areas is contained in 14 CFR Part 91,
Appendix D, Section 3. They are also depicted on sectional aeronautical charts.
f. ATC provides separation between Special VFR flights and between these flights and other IFR flights.
g. Special VFR operations by fixed-wing aircraft are prohibited between sunset and sunrise unless the pilot
is instrument rated and the aircraft is equipped for IFR flight.
h. Pilots arriving or departing an uncontrolled airport that has automated weather broadcast capability
(ASOS/AWOS) should monitor the broadcast frequency, advise the controller that they have the "one-minute
weather" and state intentions prior to operating within the Class B, Class C, Class D, or Class E surface areas.
REFERENCE-
Pilot/Controller Glossary Term- One-minute Weather.

4-4-7. Pilot Responsibility upon Clearance Issuance
a. Record ATC clearance. When conducting an IFR operation, make a written record of your clearance. The
specified conditions which are a part of your air traffic clearance may be somewhat different from those included
in your flight plan. Additionally, ATC may find it necessary to ADD conditions, such as particular departure
route. The very fact that ATC specifies different or additional conditions means that other aircraft are involved
in the traffic situation.
b. ATC Clearance/Instruction Readback. Pilots of airborne aircraft should read back those parts of ATC
clearances and instructions containing altitude assignments, vectors, or runway assignments as a means of
mutual verification. The read back of the "numbers" serves as a double check between pilots and controllers and
reduces the kinds of communications errors that occur when a number is either "misheard" or is incorrect.
1. Include the aircraft identification in all readbacks and acknowledgments. This aids controllers in
determining that the correct aircraft received the clearance or instruction. The requirement to include aircraft

4-4-4

ATC Clearances and Aircraft Separation