Guidance concerning Air Navigation in and above the NAT MNPSA
Eastbound OTS (i.e. after 2359 UTC), should plan to remain clear of the incoming/pending OTS structure.
Within RVSM Airspace greater opportunity exists for step climbs. Operators may include
step climbs in the flight plan, although each change of level during flight must be requested from ATC by the pilot. The chance of approval of such requests will, of course, be entirely dependent upon potential traffic conflicts. Outside the OTS there is a good likelihood of achieving the requested profiles. However, within the prime OTS levels at peak times, ATC may not always be able to accommodate requested flight level
changes and prudent pre-flight fuel planning should take this into consideration.
During the OTS Periods (eastbound 0100-0800 UTC, westbound 1130-1900 UTC) aircraft
intending to follow an OTS Track for its entire length may plan at any of the levels as published for that track on the current daily OTS Message. Flights which are planned to remain entirely clear of the OTS or which join or leave an OTS Track (i.e. follow an OTS track for only part of its published length), are all referred to as Random Flights. Pilots intending to fly on a random route or outside the OTS time periods,
should normally plan flight level(s) appropriate to the direction of flight.
Note: “Appropriate Direction Levels” within the NAT MNPSA are speci ied by the Semi-circular Rule Per ICAO Annex 2, Appendix 3, Table a.
Planners should note however that the AIPs specify some exceptions to use of “Appropriate
Direction Levels” both during the OTS time periods and outside them. At specified times, appropriate direction levels are reserved for use by (opposite direction) traffic flows that then predominate. These exceptions may be modified in future to accommodate changes in traffic flows. The current usage allocation of flight levels in the NAT MNPSA is published in the UK and Canadian AIPs and shown at Attachment 6 as the NAT Flight Level Allocation Scheme (FLAS). Hence, pilots and planners should always consult the current AIPs and any supporting NOTAMs when flight planning random routes through NAT MNPS Airspace.
If a flight is expected to be level critical, operators should contact the initial OAC prior to
filing of the flight plan to determine the likely availability of specific flight levels.
ATC Flight Plans
Correct completion and addressing of the flight plan is extremely important as errors can
lead to delays in data processing and to the subsequent issuing of clearances to the flights concerned. Despite the growing use of automated flight planning systems, a significant proportion of ATC Flight Plans submitted in respect of flights through the North Atlantic Region continue to contain errors. In some instances these errors are such that the Flight Plan is rejected and the Operator is required to re-submit a corrected version. Full and detailed explanations of how to complete an ATS Flight Plan in respect of the NAT portion of a flight are contained in Chapter 16 and Attachment 4 of this Manual. The Attachment also highlights the more common completion errors that are made. UK AIC 55/2003 provides similar NAT Region specific guidance and includes example completed ICAO Flight Plans. A copy of this AIC may be downloaded from http://www.nats-uk.ead-it.com/aip/current/aic/yellow/EG_Circ_2003_Y_055_en.pdf . New and/or infrequent North Atlantic operators are earnestly recommended to make diligent reference to
In order to signify that a flight is approved to operate in NAT MNPS Airspace, the letter ‘X’
shall be inserted, in addition to the letter ‘S’, within Item 10 of the flight plan. A ‘W’ must also be included
in Item 10 to indicate that the flight is approved for RVSM operations.
NAT Doc 007