Federal Aviation Administration Twentieth Edition
TBL ENR 1.4.1
Basic VFR Weather Minimums
Airspace  Flight Visibility  Distance from Clouds 
Class A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  Not Applicable  Not Applicable 
Class B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3 statute miles  Clear of Clouds 
Class C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3 statute miles  500 feet below 1,000 feet above 2,000 feet horizontal 
Class D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3 statute miles  500 feet below 1,000 feet above 2,000 feet horizontal 
Class E Less than 10,000 feet MSL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . At or above 10,000 feet MSL . . . . . . . . . . . . . . . . . . . . . . . . . . .  3 statute miles 5 statute miles  500 feet below 1,000 feet above 2,000 feet horizontal 1,000 feet below 1,000 feet above 1 statute mile horizontal 
Class G 1,200 feet or less above the surface (regardless of MSL altitude). Day, except as provided in 14 CFR Section 91.155(b) . . . . . . . . Night, except as provided in 14 CFR Section 91.155(b) . . . . . . . More than 1,200 feet above the surface but less than 10,000 feet MSL. Day . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Night . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . More than 1,200 feet above the surface and at or above 10,000 feet MSL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  1 statute mile 3 statute miles 1 statute mile 3 statute miles 5 statute miles  Clear of clouds 500 feet below 1,000 feet above 2,000 feet horizontal 500 feet below 1,000 feet above 2,000 feet horizontal 500 feet below 1,000 feet above 2,000 feet horizontal 1,000 feet below 1,000 feet above 1 statute mile horizontal 

TBL ENR 1.4.2
VFR Cruising Altitudes and Flight Levels
If your magnetic course (ground track) is:  And you are more than 3,000 feet above the surface but below 18,000 feet MSL, fly:  And you are above 18,000 feet MSL to FL 290, fly: 
0 to 179 . . . . . . . . . . . . . . .  Odd thousands MSL, plus 500 feet (3,500; 5,500; 7,500, etc.)  Odd Flight Levels plus 500 feet (FL 195; FL 215; FL 235, etc.) 
180 to 359 . . . . . . . . . . . . .  Even thousands MSL, plus 500 feet (4,500; 6,500; 8,500, etc.)  Even Flight Levels plus 500 feet (FL 185; FL 205; FL 225, etc.) 

2. Controlled Airspace
2.1 General
2.1.1 Controlled Airspace. A generic term that covers the different classification of airspace (Class A, Class B, Class C, Class D, and Class E airspace) and defined dimensions within which air traffic control service is provided to IFR flights and to VFR flights in accordance with the airspace classification. (See TBL ENR 1.4.3 for Airspace Classes). Airspace classes are pronounced in the ICAO phonetics for clarification. The term “class” may be dropped when referring to airspace in pilot/controller communications.
2.1.2 IFR Requirements. IFR operations in any class of controlled airspace requires that a pilot must file an IFR flight plan and receive an appropriate ATC clearance.
2.1.3 IFR Separation. Standard IFR separation is provided to all aircraft operating under IFR in controlled airspace.
2.1.4 VFR Requirements. It is the responsibility of the pilot to insure that ATC clearance or radio communication requirements are met prior to entry into Class B, Class C, or Class D airspace. The pilot retains this responsibility when receiving ATC radar advisories. (See 14 CFR Part 91.)
REFERENCE.
14 CFR Part 91.
2.1.5 Traffic Advisories. Traffic advisories will be provided to all aircraft as the controller’s work situation permits.
2.1.6 Safety Alerts. Safety Alerts are mandatory services and are provided to ALL aircraft. There are two types of Safety Alerts, Terrain/Obstruction Alert and Aircraft Conflict/Mode Intruder Alert.
2.1.6.1 Terrain/Obstruction Alert. A Terrain/Ob-struction Alert is issued when, in the controller’s judgment, an aircraft’s altitude places it in unsafe proximity to terrain and/or obstructions.

TBL ENR 1.4.3
Airspace Classes

Federal Aviation Administration Twentieth Edition
2.1.6.2 Aircraft Conflict/Mode C Intruder Alert.
An Aircraft Conflict/Mode C Intruder Alert is issued if the controller observes another aircraft which places it in an unsafe proximity. When feasible, the controller will offer the pilot an alternative course of action.
2.1.7 Ultralight Vehicles. No person may operate an ultralight vehicle within Class A, Class B, Class C, or Class D airspace or within the lateral boundaries of the surface area of Class E airspace designated for an airport unless that person has prior authorization from the ATC facility having jurisdiction over that airspace. (See 14 CFR Part 103.)
　
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