CHAPTER 7

GENERAL

Report to air traffic control, as soon as practicable, any event that may affect ability to comply with the current clearance, examples being: severe turbulence, loss of thrust, loss of pressurization, need to divert, uncertainty of present position, etc. If, at any time, it is not possible to notify air traffic control immediately that a problem has occurred and obtain a new clearance before departing from the old, comply as accurately as possible with any procedures that may be specified for the airspace. In all cases a good look out should be maintained, and if the aeroplane is equipped with TCAS, the visual display should be used to assist in the sighting of proximate traffic. The following equipment failures must be reported to air traffic control:

• Abnormal situation preventing the aircraft to maintain the assigned FL.
• Failure of  AP.
• Loss of altimeter indication redundancy (only one main indication remaining), or excessive altimeter discrepancy.
• Discrepancy of altitude indications without means to determine which indication is valid.
• Encountering greater than moderate turbulence.
• Failure of any other equipment that could affect the ability of the aeroplane to maintain flight as cleared.

ATC shall render all possible assistance to a pilot experiencing an in-flight contingency. Subsequent ATC actions will be based on the intentions of the pilot, the over-all air traffic situation, and the real-time dynamics of the contingency.

EUR RVSM AIRSPACE

In this RVSM airspace, it is expected that all aeroplanes will be in continuous radio contact with ATC either on the assigned frequency or on the distress and emergency frequency (121.5MHz). They will therefore be able to advise ATC of any abnormal circumstances where RVSM performance requirements cannot be met, including encounters with turbulence greater than 'moderate'. ATC will then respond and issue an appropriate revised clearance before the pilot Initiates a deviation from the original clearance. It is recognized, however, that there may be some circumstances (such as an emergency descent following the loss of cabin pressurization) where deviations may have to occur with little or no prior notice to ATC. In such cases the pilot will need to obtain a revised clearance as soon as possible after the deviation.

Contingency Procedures applicable to individual aircraft

• Where an aircraft's Mode C displayed level indicates a deviation from the cleared flight level of 300 ft or more, the controller shall inform the pilot as soon as practicable and the pilot shall return to his cleared flight level immediately.
• When informed by the pilot that the aircraft's equipment has degraded to below altimetry MASPS compliance levels while operating within the RVSM airspace, the controller shall provide for either a minimum vertical separation of 2000 ft or an appropriate horizontal separation. Controllers shall normally clear the aircraft below FL 290 before the next inter-center transfer of control point, unless otherwise coordinated.

• For the case of an individual aircraft reporting severe turbulence, the controller shall provide for either an appropriate horizontal separation, or an increased vertical separation.
• If informed of the existence of severe turbulence, the controller shall solicit other relevant turbulence reports to determine, in co-ordination with Supervisor, whether RVSM operations should be suspended entirely or within a specific level band and/or area.

(c) M.Hanke 2014