Section 13.1: Weather Deviation and RVSM Contingency Procedures
13.1.1 Weather Deviation in Oceanic Airspace
13.1.1.1 In order to indicate priority, the pilot may initiate communication by stating “WEATHER DEVIATION REQUIRED”. The pilot retains the option of initiating the communications using the urgency call “PAN PAN” three times to alert all listening parties of a special handling condition which will receive ATC priority for issuance of a clearance or assistance.
13.1.1.2 When a pilot requests clearance to deviate from track, the controller must:
(a) issue a clearance to deviate from track, if there is no conflicting traffic in the lateral dimension; or
(b) establish vertical separation and issue a clearance to deviate from track, if there is conflicting traffic in the lateral dimension; or
(c) if unable to establish vertical separation, and there is conflicting traffic in the lateral dimension;
(i) advise the pilot that clearance for the requested deviation is not available;
(ii) provide traffic about, and to, all affected aircraft; and
(iii) request pilot intentions.
Note Position may be expressed as direction and distance, or actual or estimated location or ATS route/ track code.
13.1.2 Aircraft Equipment Failures in RVSM Airspace
13.1.2.1 If a pilot of an RVSM approved aircraft operating in the RVSM flight level band advises “NEGATIVE RVSM”, the controller must, as required:
(a) pass traffic information;
(b) obtain the pilot’s intentions;
(c) provide alternative separation;
(d) update the FDR; and
(e) advise adjacent ATC facilities/sectors of the situation.
13.1.2.2 If a pilot advises that redundancy in primary altimetry systems is lost, but the remaining altimetry system is functioning normally, the controller should acknowledge the situation and continue to monitor the flight’s progress.
Note: RVSM separation may still be applied in this instance.
Section 13.2: In Flight Emergency Response
13.2.1 Emergency Changes of Level
13.2.1.1 As an emergency measure, the use of flight levels separated by 500 FT (below FL290 or in RVSM airspace) or 1,000 FT (at or above FL290 in non-RVSM airspace) may be used temporarily when standard procedural separation cannot be applied provided that traffic information is issued.
13.2.1.2 If an emergency makes it necessary to clear all traffic from a particular area, ATC must broadcast the following message:
Section (a) issue a clearance to deviate from tr - Manual of Standards Part 172—Air Traffic Services - (a) issue a clearance to deviate from track, if there is no conflicting traffic in the lateral dimension; or | Zoe
(a) “EMERGENCY TO ALL CONCERNED. EMERGENCY CLIMB/DESCENT AT… (location).” Then as required by circumstances;
(b) (for aircraft in holding pattern) “ALL AIRCRAFT ABOVE/BELOW ... (level) TURN RIGHT 90 DEGREES (for left hand holding pattern or left 90 degrees for right hand pattern)”.
13.2.2 Fuel Dumping
13.2.2.1 Airspace affected by the fuel dumped from an aircraft in flight is known as the ‘vapour zone’ and is defined as that airspace at least 1,000 FT above, 2,000 FT below, 5 NM horizontally behind and ½ NM on each side of the aircraft.
13.2.2.2 In an emergency, or when fuel must be dumped without adequate warning or delay, controllers must make every effort to keep other aircraft clear of the ‘vapour zone’. Additionally, ATS is responsible for:
(a) noting the area where jettison was affected;
(b) recording weather conditions and reporting the incident to the appropriate authority without delay.
13.2.2.3 In other than emergency circumstances ATS must specify which section of a nominated track may be used for the dumping of fuel and recommend that aircraft maintain a minimum height of 6,000 FT AGL. For safety reasons fuel is not to be dumped in a circular or race-track pattern.
13.2.2.4 For the purpose of providing separation, all the airspace containing the track specified, the selected altitude and a full allowance for the ‘vapour zone’ must be treated as reserved airspace from the time dumping is expected to commence until 5 MIN after it has been completed.
13.2.2.5 Known aircraft in Class G airspace likely to be affected are to be warned of the fuel dumping and the approximate location of the ‘vapour zone’.
13.2.2.6 The warning must also be broadcast on the appropriate frequencies. Warnings are to continue during the period of fuel dumping and for 5 MIN after it has been completed.