21. A) Different types of flights.

Air transportation is the carriage of passengers, mail and freight by aircraft or helicopters. All air transportations are classified according to the territorial sign, to the objects of transportation and to the direction of transportation.

By the territorial division they are defined as domestic and international flights. Domestic and international flights are divided into schedule and non-schedule flights. Schedule flights are performed according to definite traffic schedule. Non-schedule flights are operated in accordance with special agreements and orders. On international routes they are known as charter flights.

Depending upon the object of transportation we define passenger, mail, load and freight flights.

As to their direction the flights differ as non-stopover flights, that is from the point of departure to the point of destination; round trips, from the point of departure to the point of destination and back to the starting point; and onward journey with the transfer from one airplane to another.

b) Why does the profession of an ATCO carry a high level of responsibility?

An ATCO is responsible for safety of flights and this is the main objective of ATC service. A controller is a master of the sky, a conductor of airways and routes. He controls all air traffic. A plane cannot take-off or make any manoeuvre without prior permission of ATC. A controller knows about his plane everything - its position now and in 5 minutes, the number of passengers on board, its endurance, the meteorological conditions of flight. A controller hears the plane and observes it on the radar screen. He is ready to help the crew at any time - from start up moment up to landing.

22. A) Convective storms. Why are they dangerous?

Hazardous conditions created by bad weather develop many components of the aviation weather system. For flight operations in the terminal area, including airports, the main threats include microbursts and low-level windshear, severe turbulence, lightning, and hazardous levels of precipitation (extremely heavy rain, large hail). In the en-route environment, convective storms can create regions of severe turbulence.

The term convective storms covers a wide range of possible storm phenomena, which range from rain, hail or drizzle to cold fronts or snow showers. Convective storms seriously disrupt ATC operations, especially in terminal control area (TMA) and airport environments. The major problems created by convective storms are delays, diversions, and cancellations when airport operations are curtailed. Accurately forecasting the appearance of convective weather is a major challenge facing the meteorological community.

b) Identification of aircraft.

Before providing radar service to an aircraft, radar identification shall be established and the pilot informed.

If radar identification is lost, the pilot shall be informed about that and, if possible, appropriate instructions issued.

Where SSR is used, aircraft may be identified by one or more of the following procedures:

a. recognition of the aircraft identification in a radar label;

b. recognition of the aircraft discrete code, the setting of which has been verified, in a radar label;

c. direct recognition of aircraft identification of a Mode S-equipped aircraft in a radar label;

d. by transfer of radar communication;

e. observation of compliance with an instruction to set a specific code;

f. observation in compliance with an instruction to squawk IDENT.

When a discrete code has been assigned to an aircraft, a check shall be made at the earliest opportunity to ensure that the code set by a pilot is identical to that assigned for the flight. Only after this check has been made shall the discrete code be used as a basis for identification.

Where SSR is not available, radar identification shall be established by at least one of the following methods:

a. by correlating a particular radar position indication with an aircraft reporting its position over, or as bearing and distance from, a point displayed on the radar map, and by ascertaining that the position is consistent with an aircraft path or reported heading;

b. by correlation an observed radar position indication with an aircraft which is known to have just departed, provided that the identification is established within 2 km( 1 NM) from the end of the runway used. Particular care should be taken to avoid confusion with aircraft holding over or overflying the aerodrome, or with aircraft departing or making a missed approach over adjacent runways;

c. by transfer of radar communication;

d. by ascertaining the aircraft heading, if circumstances require, and following a period of track observation:

e.▫instructing the pilot to execute one or more changes of heading of 30 degrees or more and correlating the movement of one particular radar position indication with the aircraft’s acknowledged execution of the instruction given, or

f.▫correlating the movements of a particular radar position indication with manoevres currently executed by an aircraft having so reported.

When using these methods, the radar controller shall:

i. verify that the movements of more than one radar position indication correspond with those of the aircraft; and

ii. ensure that the manoevre(s) will not carry the aircraft outside the coverage of the radar display.

Use may be made of direction-finding bearings to assist in radar identification of an aircraft.

When doubt exists as to identify of a radar position identification for any reason, changes of heading should be prescribed and repeated as many times as necessary, or additional methods of identification should be applied.