Airspace

1. References: FAR Part 61, Part 91, AIM
AIRSPACE
1,000’
2,000’
500’

2. Contents
 General Information
 Class A
 Class B
 Class C
 Class D
 Class E
 Class G

3. Contents (Continued)
 Airport Advisory Areas
 Restricted Areas
 Prohibited Areas
 Warning Areas
 Alert Areas
 Military Operations Areas
 Controlled Firing Areas

4. Characteristics
 Dimensions
 VFR Weather
 Equipment Requirements
 Restrictions

5. General Information
 Two categories of airspace:
 regulatory (restricted & prohibited areas)
 non-regulatory (warning areas, & MOAs)
 Within these categories there are four types:
 controlled (A, B, C, D, & E)
 uncontrolled (G)
 special use (warning, restricted, & prohibited
areas)
 other (airport advisory area)

6. Class A
 Begins at 18,000’ MSL; extends up to and
including FL 600 (excluding airspace less
than 1,500’ AGL in Alaska). Extends out to
12 NM from the coast.
 VFR Weather - N/A
 Equipment - Mode C Transponder and two
way radio.
 No VFR or VFR on top authorized.
 ATC clearance required.

7. Surface
Class A
18,000’ MSL
FL 600

8. Class B
 Extends from surface or higher to specific
altitudes individually tailored, but generally
terminating at 10,000’ MSL. Resembles upside
down wedding cake.
 VFR weather 3 SM visibility and clear of clouds.
 Mode C transponder inside & within 30 NM, and
two way radio.
 250 KIAS limit below 10,000’ MSL, 200 KIAS in
airspace underlying the Class B, or in VFR
corridors within.
 ATC clearance required.

9. Surface
Class A
18,000’ MSL
FL 600
Class B

10. Class C
 Dimensions are individually tailored but
usually consist of a 5 NM radius core
surface to 4,000' above the airport
elevation, and a 10 NM radius shelf from
1,200' to 4,000' above the airport
elevation, and a 20 NM radius outer area
extending from the lower RADAR limits to
the ceiling of the approach control’s
airspace.

11. 5 NM
Class C (Continued)
10 NM
4,000’
AGL
Core
Shelf
Outer
Area
20 NM
1,200’
AGL

12. Class C (Continued)
 VFR weather: 3 SM visibility & basic cloud
clearance of 500’ below, 1,000’ above &
2,000’ horizontal.
 Mode C transponder, & two way radio.
 250 KIAS below 10,000’ MSL, and 200 KIAS
within 4 NM of the primary airport below
2,500’ AGL. ATC clearance required.

13.  VFR Arrival Communications: two way
contact is established if the controller repeats
your aircraft call sign.
 Satellite Operations: departing an
uncontrolled satellite airport that underlies
Class C airspace, the pilot shall contact ATC
as soon as possible after takeoff.
Class C (Continued)

14.  Secondary Airports:where Class C
overlies other Class D airspace portions
of the overlapping Class C may be
procedurally excluded when the
secondary control tower is open.
Class C (Continued)

15. Surface
Class A
18,000’ MSL
FL 600
Class B
Class C

16. Class D
 Surface to 2,500' AGL (depicted in MSL)
 Airspace based on Instrument procedures
needed for that airport
 VFR weather: 3 SM visibility & basic cloud
clearance of 500’ below, 1,000’ above &
2,000’ horizontal, and 1,000' ceiling.
 Two way radio.
 Special VFR needed if Conditions are below
1000’ ceilings and or less than 3SM visibility.
 To Obtain SVFR - Clearance from ATC and
at least a private pilot Certificate

17. Surface
Class A
18,000’ MSL
FL 600
Class B
Class C
Class D

18. Class E
 Begins at 14,500’ MSL (excluding below
1,500’ AGL) and extends up to, but not
including 18,000’ MSL. May also begin at the
surface, 700’ AGL, 1,200’ AGL or other
altitudes.
 VFR weather (same as Class C, & D) except
Above 10,000’ MSL - 5SM Visibility - 1,000’
above, 1,000’ below, & 1 SM horizontal.
 No equipment requirements (VFR).
 250 KIAS below 10,000’ MSL.

19. Surface
Class A
18,000’ MSL
FL 600
Class B
Class C
Class D
Class E
14,500’ MSL
1,200’AGL
700’AGL
Class E
E

20. Glass G
 Uncontrolled airspace from surface to the
base of the overlying controlled airspace
(700’, 1,200’, 14,500’ etc.).
 VFR weather per 91.155(b) -
 Below 1200’ AGL -Clear of Clouds
 Above 1200’/Below 10,000’MSL -
 Day:1SM - Night: 3SM
 500B, 1000A, 2000H
 Above 1200’/Above 10,000’MSL
 Day or Night - 5SM 1000B, 1000A, 1SMH
 No equipment requirement.

21. Surface
Class A
18,000’ MSL
FL 600
Class B
Class C
Class D
Class E
14,500’ MSL
Class G
E
Class E

22. Overlapping Airspace
 When overlapping airspace designations
apply to the same airspace, the operating
rules associated with the more restrictive
airspace applies:
 Class A is more restrictive than B, C, D, E or G.
 Class B is more restrictive than C, D, E, or G.
 Class C is more restrictive than D, E, or G.
 Class D is more restrictive than E, or G.
 Class E is more restrictive than G.

23. Prohibited Area
 Contain airspace within which the flight
of aircraft is prohibited; established for
security or other reasons associated
with national welfare.

24. Restricted Area
 Contain airspace within which the flight of
aircraft while not wholly prohibited, is
subject to restrictions. Activities in these
areas must be confined due to the
existence of unusual, often invisible,
hazards to aircraft such as artillery firing,
aerial gunnery, or guided missiles.
 Must contact Controlling agency prior to
entrance.
 VFR? Squawk 1200.

25. Alert Area
 Established to inform nonparticipating
pilots of areas that may contain a high
volume of military pilot training or an
unusual type of aerial activity. All
activity in an Alert Area shall be
conducted in accordance with FARs.

26. Warning Area
 Extend from 3 NM outward from the
coast of the US and may contain activity
that could be hazardous to
nonparticipating aircraft. May be
located over domestic or international
airspace.

27. Controlled Firing Area
 Contain activities, which, if not
conducted in a controlled environment,
could be hazardous to nonparticipating
aircraft. CFA activities are suspended
when RADAR, ground lookouts, or
spotter aircraft indicate an aircraft may
be approaching the area.

28. Military Operations Area
 Established for the purpose of separating
certain military training activities from
nonparticipating IFR traffic. Since most
military training activities necessitate
acrobatic or abrupt flight maneuvers
military pilots in MOAs are exempt from
FARs prohibiting aerobatic flight. VFR
pilots should contact FSSs within 100
miles of MOAs for operating hours.

29. Military Training Routs (MTR’s)
 Definition: Routes used by the military to practice high-speed, low altitude
maneuvers. Generally below 10,000’MSL and airspeeds greater than 250kts.
 Status: IFR and VFR traffic are not prohibited from flying along the route, but
should contact an FSS within 100 miles of the route for current activity
 Charts: All MTR’s have been assigned a unique designator composed of two
letters and either three or four numbers.
 ｷ The two letters inform pilot of the type of operations that are
performed along the route:
 o VR – Visual Rules – See and avoid.
 o IR – Instrument Rules – IFR separation
 ｷ The number of digits informs the pilot of the altitude at which
these operations will be conducted:
 o 3 digits – both above and below 1,500’AGL
 o 4 digits - at or below 1,500’AGL

30. Temporary Flight Restrictions (TFR’s)
 Definition: May be issued by the FAA whenever an incident or accident
has occurred that has potential for attracting a number of aircraft that
may cause a hazard to those attempting to rescue or to those persons
on the ground (for example: fire, earthquake, aircraft accident site, etc.)
 FAA notifies Pilots of TFR’s through the issuance of NOTAM’s
through FAA controlling facilities, military and airlines.
 The NOTAM will contain information pertaining to the actual
location, dimension, duration of the TFR and information of
which aircraft are permitted to operate within the TFR.
(generally 2000’agl and 2-3NM radius around the site)
 Aircraft that may operate within the TFR
 Aircraft aiding in disaster relief as approved by the FAA
 IFR aircraft properly cleared by ATC.

31. Federal Airways
 Definition: Provide routes between VOR’s/NDB’s to aid IFR traffic routes.
 Two types of Federal airways
 Colored airways: use NDB’s and 4 course radio ranges for
navigation (no longer in use except in Canada and Alaska)
 VOR airway system: use VOR’s (used in the US since 1950’s)
 VOR airway system uses low altitude or Jet Routes
 Low altitude airways are described in FAR 71 and utilize both high
and low altitude VOR’s. They are assigned a distinct number
identifier prefixed with the letter “V” (for example: V-105)
 Low altitude airways extend from 1,200’AGL up to (but not
including) 18,000’MSL and extended 4NM laterally on.
 Jet routes extend from 18,000’ MSL up to and including FL450 and
identified with a unique number and the prefix “J” (for example, J-
105)
 Charts: Depicted as light blue lines with their identifying number on
sectional and L-charts.

32. Airport Advisory Area
 The area within 10 SM of an airport
where a control tower is not operating
but where a FSS is located. Non-
mandatory, but strongly recommended
that pilot participate.
 Not depicted on Charts.

33. Terminal Radar Service Areas (TRSA’s)
 Definition: Originally established as part of the terminal radar
program at selected airports. TRSA’s are not considered controlled
airspace and are not governed by FAR 71.
 The primary airport within a TRSA is considered to be class
D airspace. The remaining portion of the TRSA (designed
much like a miniature Class B airspace) is considered to be
Class E, starting at 700’agl or 1,200’ AGL
 VFR pilots are encouraged but not required to contact radar
approach prior to entering class D airspace. VFR pilots
must contact the tower prior to entering Class D.
 Charts: Sectional: solid black lines and altitudes for each segment.
Class D portion is blue dashed line.

34. Questions?
Within the US, the floor of Class A airspace is
___________ ?
 18,000’ MSL.
What are the VFR weather requirements for
Class B airspace?
 3 SM visibility and clear of clouds.
What are the dimensions of Class C
airspace?
 5 NM radius core from surface to 4,000’ AGL,
10 NM radius shelf from 1,200’ AGL to 4,000’
AGL, and a 20 NM radius outer area.

35. Questions?
When a control tower, located on an
airport within Class D airspace ceases
operation for the day, what happens to the
airspace designation?
 Class D airspace requires an operational
control tower. When that tower ceases to
operate, it reverts to Class E. Without
weather reporting capability it reverts to
Class G.

36. Questions?
What are Class E VFR weather
minimums above 10,000’ MSL?
 5 SM visibility, 1,000’ above, 1,000’
below and 1 SM horizontal.
1,000’
1,000’
1 SM 5 SM Vis.

37. Questions?
VFR flight is not authorized in a MOA?
 True
 False
VFR pilots should exercise extreme caution in MOAs and
contact any FSS within 100 miles of the area to obtain
real-time information concerning the MOA hours of
operation. Prior to entering an active MOA , VFR pilots
should contact the controlling agency for traffic advisories.

38. Bonus Question
Where is a mode C transponder required?
 Above 10,000’ MSL (excluding below 2,500’ AGL).
 Within Class A, B, or C airspace.
 Within 30 NM of a Class B primary airport below
10,000’ MSL.
 Above Class C airspace below 10,000’ MSL.
 Crossing the ADIZ of the United States.