ENR 1.1 GENERAL RULES
1. GENERAL
The rules and procedures applicable to air traffic in Oman generally conform with Annexes 2 and 11 to the Convention on International Civil Aviation (Chicago Convention) and those portions, applicable to aircraft, of the Procedures for Air Navigation Services - Air Traffic Management (PANS-ATM, Doc 4444) and the Regional Supplementary Procedures (Doc 7030) in force for the MID part of the MID/ASIA Region.
2. AIR TRAFFIC CONTROL CLEARANCE
An air traffic clearance constitutes authorisation for an aircraft to proceed under conditions specified by an air traffic control unit to a clearance limit under specified conditions. Further clearance is required upon reaching the limit in the clearance.
Clearances are issued solely for expediting and separating air traffic and are based on known traffic conditions which affect safety in aircraft operation. Such traffic conditions include not only aircraft in the air and on the manoeuvring area over which control is being exercised, but also any vehicular traffic or other obstructions not permanently installed on the manoeuvring area in use.
If an air traffic control clearance is not suitable to the pilot-in-command of an aircraft, the flight crew may request and, if practicable, obtain an amended clearance.
ATC clearances do not constitute authority to violate any applicable regulations for promoting the safety of flight operations or for any other purpose; neither do clearances relieve a pilot-in-command of any responsibility whatsoever in connection with a possible violation of applicable rules and regulations.
3. ADHERENCE TO CLEARANCE FOR IMMEDIATE TAKE-OFF
All operators are reminded that when ATC clears an aircraft for IMMEDIATE TAKE-OFF, the aircraft is to enter the runway and commence its take-off roll without stopping. If unable to comply with this instruction, ATC shall be notified before the aircraft enters the runway.
4. AIR TRAFFIC CONTROL INSTRUCTIONS
Air traffic control instructions are directives issued by air traffic control for the purpose of requiring a pilot to take a specific action. A pilot is required to comply with an ATC instruction or shall inform ATC if unable.
5. READBACK OF ATC CLEARANCE AND INSTRUCTIONS
5.1 The flight crew shall read back to the air traffic controller safety-related parts of ATC clearances and instructions which are transmitted by voice. The following items shall always be read back:
a) ATC route clearances;
b) clearances and instructions to enter, land on, take off from, hold short of, cross, taxi and backtrack on any runway; and
c) runway-in-use, altimeter settings, SSR codes, level instructions, heading and speed instructions and, whether issued by the controller or contained in Automatic Terminal Information Service (ATIS) broadcasts, transition levels.
5.2 Other clearances or instructions, including conditional clearances, shall be read back or acknowledged in a manner to clearly indicate that they have been understood and will be complied with.
6. CLEARANCE TO FLY MAINTAINING OWN SEPARATION
In Class A and C Airspace clearance to fly maintaining own separation in VMC will NOT be granted.
In Class D airspace, when so requested by an aircraft and provided it is agreed by the pilot of the other aircraft, an ATC unit may clear a controlled flight, including departing and arriving flights, operating in visual meteorological conditions during the hours of daylight to fly subject to maintaining own separation to one other aircraft and remaining in visual meteorological conditions provided the clearance shall be for a specified portion of the flight
i) at or below 10000 FT AMSL, during climb or descent; and
ii) the separation is achieved before entering Class A or C Airspace.
The pilot of an IFR flight, on observing that conditions are deteriorating and considering that operation in VMC will become impossible, shall inform ATC before entering instrument meteorological conditions (IMC) and shall proceed in accordance with the alternative instructions given.
Over the high seas flights may encounter State aircraft operating with due regard. Such traffic is not subject to an ATC Clearance and traffic information will be passed to other operating traffic if available.
7. HORIZONTAL SPEED CONTROL INSTRUCTIONS
In order to facilitate a safe and orderly flow of traffic, aircraft may, subject to conditions specified by the appropriate authority, be instructed to adjust speed in a specified manner.
Speed control instructions shall remain in effect unless explicitly cancelled or amended by the controller. The pilot shall inform the ATC unit concerned if at any time they are unable to comply with a speed instruction. Pilots shall adhere to the speed limits associated with airspace classifications and the speed restrictions notified in procedures published in AD 2. Pilots shall also adhere to the speed (IAS or Mach Number) approved or assigned by ATC and shall request ATC approval before making any changes thereto. If it is essential to make an immediate temporary change in speed (e.g. due to turbulence), ATC shall be notified as soon as possible that such a change has been made.
Pilots of aircraft unable to maintain the last assigned speed during any particular phase of flight (e.g. for aircraft performance reasons) shall inform ATC as soon as possible in order that another speed/alternative clearance can be issued.
At levels at or above FL280, speed adjustments for aircraft in the cruise will be expressed in multiples of 0.01 Mach. At levels below FL280, speed adjustments will be expressed in multiples of 10 KT based on indicated airspeed (IAS).
For aircraft at or above FL280 that have been cleared to descend to levels below FL280, speed adjustments may be based on IAS.
8. VERTICAL SPEED CONTROL INSTRUCTIONS
In order to facilitate a safe and orderly flow of traffic, aircraft may be instructed to adjust rate of climb or rate of descent. Vertical speed control may be applied between two climbing aircraft or two descending aircraft in order to establish or maintain a specific vertical separation minimum.
The flight crew shall inform the ATC unit concerned if unable, at any time, to comply with a specified rate of climb or descent.
9. POSITION REPORTING
Pilots are to make a position report in the following circumstances:
a) after transfer of communication;
b) on reaching the limit of ATS clearance;
c) when instructed by Air Traffic Control;
The position reports shall contain the following elements of information:
a) aircraft identification;
b) position (and time if required by ATC);
c) flight level or altitude, including passing level and cleared level if not maintaining the cleared level;
d) When assigned a speed to maintain, the flight crew shall include this speed in their position reports. The assigned speed shall also be included in the initial call after a change of air-ground voice communication channel, whether or not a full position report is required.
10. AERODROME FLIGHT INFORMATION SERVICE (AFIS)
Aerodrome Flight Information Service (AFIS) is the term used to describe the provision of information useful for the safe efficient conduct of aerodrome traffic at those aerodromes where the provision of aerodrome control service is not justified. Accordingly, AFIS units have been established at certain aerodromes to provide flight information service and alerting service to aerodrome traffic.
Note: An AFIS unit does not provide an Aerodrome Control Service
It is therefore the responsibility of pilots using the service provided by this unit to maintain proper separation in conformity with the rules of the air. When operating in the vicinity of an aerodrome where AFIS is provided, pilots must, on the basis of the information received from the AFIS unit, combined with their own knowledge and observations, decide on the course of action to be taken to ensure separation from other aircraft, ground vehicles and obstacles.
Aircraft operating within an Aerodrome that provides AFIS are required to maintain two-way radio communications with the AFIS unit on the prescribed frequency.
The AFIS unit will provide information enabling the pilot to select the most suitable runway for use. Such information should include, in addition to the current surface wind direction and speed, the 'preferred runway' and traffic pattern and, on request by the pilot, the length of the runway and/or the distance between an intersection and the end of the runway;
Note: The term 'preferred runway' is used to indicate the most suitable runway at a particular time, taking into account the current surface wind direction and speed and other relevant factors such as the traffic pattern and the runway used by other aircraft, with the intention of establishing and maintaining an orderly flow of aerodrome traffic.
AFIS units will provide the following basic information to aircraft:
a) Meteorological information for aircraft about to take off or land, including SIGMET/AIRMET information;
b) Current surface wind direction and speed, including significant variations, indicating the "preferred runway";
c) The current QNH altimeter setting;
d) The air temperature, when requested, in the case of take off by turbine engine aircraft;
e) The current visibility in the direction of take-off and initial climb, or in the approach and landing area if less than 10 KM, or the RVR (if available);
f) Significant meteorological conditions in the take off and climb out area, or in the approach and landing area;
g) The present weather and the amount and the height of the base of low cloud, in the case of aircraft making an approach in IMC;
h) Information on other known aircraft, vehicles or personnel on or near the manoeuvring area that may constitute a hazard;
i) Information on aerodrome conditions, status of navigation aids, messages, including clearances received from ATS units for relay to aircraft; and
j) Any other information contributing to safety.
AFIS units do not provide clearances to land or take-off however pilots shall confirm with AFISO that runway is clear for Landing & Take-off before commencing the take-off roll or landing.
AFIS units control ground movement by means of AFIS instructions. Pilots shall readback such safety related parts of such instructions and comply with the instructions unless advising the AFIS unit that they are unable.
Entering and Backtracking a runway is done at pilot’s discretion, however the pilot should confirm with the AFIS unit if there is any traffic that may affect. Pilots should hold short of all runways until confirming that there is not traffic to affect them entering the runway.
11. FLIGHT INFORMATION SERVICE
Enroute aircraft when flying in Class G airspace and in radio contact with an air traffic services unit will receive flight information (FIS) on other aircraft known to be in their vicinity. When within radar Coverage from Muscat Control or Muscat a radar derived advisory service may be provided to IFR and VFR flights operation outside CAS.
12. TESTING OF EMERGENCY LOCATOR TRANSMITTER (ELT)
12.1 General
The following standard procedures shall be used for testing of Emergency Locator TRANSMITTER (ELT) within the MUSCAT FIR. To preclude unnecessary activation of relevant ATS/SAR services, all aircraft operators are requested to comply.
12.2 ELT Testing
Caution should be exercised to prevent inadvertent actuation of locator beacons in the air or on the ground. Operational testing of beacons should be carried out only in shielded areas under controlled conditions. False signals on the distress frequencies can interfere with the distress transmission as well as decrease the degree of urgency attached to such signals. Aircraft operational testing is authorized as follows:
a) Test should be no longer than 3 audio sweeps;
b) If the antenna is removable, a dummy load should be substituted during test procedures;
b) Tests should be conducted only within the first five minutes of each hour. Emergency tests outside of this time shall be coordinated with the nearest ATC unit. Airborne ELT tests are not authorized.