Class G airspace has the fewest restrictions and is closest to the ground, while Class A airspace is the most restrictive and prohibits VFR flight. Each class has different pilot certification, equipment, and weather minimum requirements that become more stringent from Class G to Class A airspace. Special use airspaces also exist for security or military reasons and may impose additional limitations on aircraft. Knowledge of the national airspace system is essential for safe cross-country soaring flights.

1. Teaching theTeaching the
National Airspace SystemNational Airspace System
Soaring Safety Foundation
FIRC
Rich Carlson

2. AirspaceAirspace
Hierarchical layout
– Class G Least restrictive, close to ground
– Class E Few restrictions, most glider flights
– Class D Minor restrictive, control tower
– Class C Restrictive, need radio & mode ‘C’
– Class B Very restrictive, 31 airports
– Class A Most restrictive, no VFR operations

3. Airspace & SafetyAirspace & Safety
Preparation for cross country
soaring flight is the essence of the
Bronze Badge training program.
Cross country soaring requires
knowledge of, and participation in,
the nation’s airspace system.
Keep up-to-date on the airspace
environment in which you plan to fly.

4. Teaching the NASTeaching the NAS
Use simple (Class G) to complex
(Class A) method
– Pilot, Aircraft, Environment
Introduce basics and then add
exceptions (grammar rules)
Use mnemonic’s to aid in learning
– G for Ground, B for Busy

5. Class “G” AirspaceClass “G” Airspace
Class G airspace is that portion of the
airspace that has not been designated
as Class A, Class B, Class C, Class D,
or Class E airspace.
No specific pilot certification is
required.
No specific equipment is required.
Transition to E is shown on Sectional.

6. Low Altitude Class “G” AirspaceLow Altitude Class “G” Airspace
VFR Weather MinimumsVFR Weather Minimums
1,200 feet or less above
the surface (regardless
of MSL altitude):
– Minimum visibility:
• 1 statute mile
– Cloud clearance:
• Clear of clouds
More than 1,200 feet
above the surface but
less than 10,000 feet
MSL:
– Minimum visibility:
• 1 statute mile
– Cloud clearance:
• 500 feet below
• 1,000 feet above
• 2,000 feet horizontal

7. High Altitude Class “G” AirspaceHigh Altitude Class “G” Airspace
VFR Weather MinimumsVFR Weather Minimums
More than 1,200 feet above the
surface and at or above 10,000 feet
MSL:
– Minimum visibility:
• 5 statute miles
– Minimum cloud clearance:
• 1,000 feet below
• 1,000 feet above
• One mile horizontal

8. Class “E” AirspaceClass “E” Airspace
Generally, if the airspace is not Class A,
Class B, Class C, or Class D, and it is
above 700’/1200’ AGL, it is Class E
airspace.
No specific pilot certification is required.
No specific equipment is required.
Transition from G is shown on Sectional.

9. Class “E” AirspaceClass “E” Airspace
VFR Weather MinimumsVFR Weather Minimums
Below 10,000 feet
MSL:
– Minimum visibility:
• 3 statute miles
– Cloud clearance:
• 500 feet below
• 1,000 feet above
• 2,000 feet horizontal
Above 10,000 feet
MSL:
– Minimum visibility:
• 5 statute miles
– Cloud clearance:
• 1,000 feet below
• 1,000 feet above
• One mile horizontal

10. Class “G” to Class “E”Class “G” to Class “E”
Pilot - No change
Aircraft - No change
Environment - Increase VFR visibility
and cloud separation minimums

11. Class “D” AirspaceClass “D” Airspace
Class D airspace is designated
around airports with an operating
control tower.
Class D airspace structure resembles
a simple hockey puck.

12. Class “D” AirspaceClass “D” Airspace
Depiction On SectionalsDepiction On Sectionals
Class D airspace is depicted on
Sectional charts by a circle, drawn
with a dashed blue line.
Ceiling of the Class D airspace is
noted within the circle on the
Sectional.

13. Class “D” AirspaceClass “D” Airspace
Entry RequirementsEntry Requirements
– Radio contact should be initiated far
enough from the Class D airspace
boundary to preclude entering the Class
D airspace before two-way radio
communications are established.
– Pilots of arriving aircraft should contact
the control tower on the publicized
frequency and give their position,
altitude, destination, and any request(s).

14. Class “D” AirspaceClass “D” Airspace

15. Class “E” to Class “D”Class “E” to Class “D”
Pilot - Radio procedures
– Establish radio contact
Aircraft - Increase aircraft equipment
– Radio
Environment - Increase airspace
complexity
– Depicted on sectional

16. Class “C” AirspaceClass “C” Airspace
Class C airspace is designated
around selected airports.
Class C airspace structure resembles
an upside-down two-layer cake.

17. Class “C” AirspaceClass “C” Airspace
Depiction On SectionalsDepiction On Sectionals
Class C airspace is depicted on
Sectional charts by concentric
circles, drawn with a solid magenta
line.
Ceiling height and floor height of
each Class C airspace layer is shown
on the Sectional (in hundreds of feet
MSL).

18. Class “C” AirspaceClass “C” Airspace
Entry RequirementsEntry Requirements
Class C airspace entry requires:
– Operating two-way radio, with radio
contact established.
– Altitude-encoding transponder (Mode C
or Mode S).

19. Class “C” AirspaceClass “C” Airspace

20. Class “D” to Class “C”Class “D” to Class “C”
Pilot - No change
Aircraft - Increase aircraft equipment
– Transponder
– Altitude Encoder
Environment - Increase airspace
complexity
– Dual rings
– Cut-outs, wedges, varying heights

21. Class “B” AirspaceClass “B” Airspace
Class B airspace is designated
around very large, busy airports.
Class B airspace structure generally
resembles an upside-down wedding
cake of three layers or more.
At this writing there are 31 Class B
airspace installations in the United
States.

22. Class “B” AirspaceClass “B” Airspace
Depiction On SectionalsDepiction On Sectionals
Class B airspace is depicted on
Sectional charts by concentric
circles, drawn with a solid blue line.
Ceiling height and floor height of
each Class B airspace layer is shown
on the Sectional (in hundreds of feet
MSL).

23. Class “B” AirspaceClass “B” Airspace
Entry RequirementsEntry Requirements
Class B airspace entry requires:
– Two-way radio communication.
– Permission to enter.
– Altitude-encoding transponder (Mode C
or Mode S).
– In some cases, Private Pilot (or higher)
pilot licensure.

24. Class “B” AirspaceClass “B” Airspace

25. Class “C” to Class “B”Class “C” to Class “B”
Pilot - Requires
– Private pilot or better in 12
– Logbook endorsements in others
– Permission to enter
Aircraft - No change
Environment - Increase airspace
complexity
– Multiple rings
– Cut-outs, wedges, varying heights

26. Mode C Veil AirspaceMode C Veil Airspace
– Mode C veil airspace surrounds Class B
airspace installations.
– For many aircraft, flight within Mode C veil
airspace requires an altitude-encoding
transponder.
– Gliders, balloons, and airplanes certified
without an engine-driven electrical system
are exempt from the altitude encoding
transponder requirement when flying in
Mode C veil airspace.

27. Mode C Veil Airspace DepictionMode C Veil Airspace Depiction
Mode C veil airspace is depicted on
Sectional charts by a labeled circle,
drawn with a solid magenta line.
The radius of the Mode C veil
airspace is printed in magenta-
colored letters on the Sectional
chart.

28. Class “A” AirspaceClass “A” Airspace
– The floor of Class A airspace is 18,000 feet
MSL (Flight Level 180), and the ceiling is
60,000 feet MSL (Flight Level 600).
– Class A airspace overlies the entire United
States.
– Flights in Class A airspace are conducted
under Instrument Flight Rules and are under
positive control from the ground.
– VFR flight is not permitted in Class A
airspace.

29. Class “A” AirspaceClass “A” Airspace
Depiction On SectionalsDepiction On Sectionals
Class A airspace overlies the entire
United States. For this reason, Class
A airspace is not depicted on
sectional charts.

30. Class “B” to Class “A”Class “B” to Class “A”
Pilot - Increase pilot requirements
– Instrument rating
– Communications with ATC
Aircraft - Compliance with FAR’s
– Pitot/Static check
– IFR instruments
– IFR certification certificate
Environment
– High Altitude systems (cold, O2)

31. US AirspaceUS Airspace

32. ExceptionsExceptions
The basic NAS laid out in this talk
defines the US Airspace rules.
However, just as in grammar there
are exceptions (e.g., I before E
except after C).

33. ExceptionsExceptions
Class E airspace to the ground
No transponder exception for
overflight of Class B or C airspace
Special use Airspace

34. Special Use AirspaceSpecial Use Airspace
Within special use airspace,
limitations may be imposed on
aircraft.
Except for controlled firing areas,
special use airspace areas are
depicted on aeronautical charts.

35. Special Use AirspaceSpecial Use Airspace
Special use airspace types:
– Temporary Flight Restrictions
– Prohibited areas
– Restricted areas
– Warning areas
– Military operations areas (MOA's)
– Alert areas
– Victor Airways
– Military Training Routes

36. Temporary Flight RestrictionsTemporary Flight Restrictions
Added to system by FDC NOTAM.
Not depicted on sectionals.
May appear with little notice!
Some common TFR’s
– Presidential visits and movement.
– Major sporting events.
Check with FSS before flight.

37. Prohibited AreasProhibited Areas
Prohibited areas are established for
security or other reasons associated
with the national welfare.
No flight is allowed in Prohibited
areas.
Prohibited areas are depicted on
Sectional charts.

38. Restricted AreasRestricted Areas
Restricted areas are established for
security or military reasons.
– Restricted areas denote the existence of
hazards to aircraft such as artillery
firing, aerial gunnery, or guided
missiles.
– Penetration of restricted areas without
authorization from the using or
controlling agency may be extremely
hazardous.

39. Restricted AreasRestricted Areas
Restricted airspace is depicted on
Sectional charts.
Before entering a Restricted area,
contact the controlling authority
(usually FAA Flight Service).

40. Warning AreasWarning Areas
Warning areas contain activity that
may be hazardous to non-
participating aircraft.
Warning areas extend from three
nautical miles outward from the
coast of the U.S.
Warning areas are depicted on
Sectional charts.

41. Military Operation AreasMilitary Operation Areas
(MOA’s)(MOA’s)
MOA's exist to separate military flight
training activities from other traffic.
– Most military flight training activities
necessitate acrobatic or abrupt flight
maneuvers.
– Pilots operating under VFR should
exercise extreme caution while flying
within a MOA when military activity is
being conducted.

42. Military Operation AreasMilitary Operation Areas
(MOA’s)(MOA’s)
– The activity status (active/inactive) of
MOA's may change frequently.
– Pilots should contact any FSS within
100 miles of the area to obtain the MOA
hours of operation.
– Before entering an active MOA, pilots
should contact the controlling agency
for traffic advisories.

43. Alert AreasAlert Areas
Alert areas exist to inform pilots of
areas that may contain a high volume
of pilot training or an unusual type of
aerial activity.
Pilots should be particularly alert for
other traffic when flying in these
areas.
Alert areas are depicted on Sectional
charts.

44. Victor AirwaysVictor Airways
Victor Airways are aerial highways
that connect electronic navigation
aids.
– Victor Airways carry a high volume of
VFR and IFR traffic.
– Flight near Victor Airways requires extra
vigilance to see and avoid other traffic.
– Victor Airways are 8 nautical miles wide
(4 n.m. either side of the centerline).

45. Military Training RoutesMilitary Training Routes
(MTR’s)(MTR’s)
Military Training Routes are usually
established below 10,000 feet MSL
for operations at speeds in excess of
250 knots. Route segments may be
defined at higher altitudes for
purposes of route continuity.

46. Military Training RoutesMilitary Training Routes
(MTR’s)(MTR’s)
– IFR Military Training Routes - (IR)
• Operations on these routes are conducted
in accordance with Instrument Flight Rules
regardless of weather conditions.
– VFR Military Training Routes - (VR)
• Operations on these routes are conducted
in accordance with Visual Flight Rules.