World Air Ops | NAT | Doc 007 MNPS Guidance

Guidance concerning Air Navigation in and above the NAT MNPSA CHAPTER 16is seldom a problem as long as at least 1 degree of separation is subsequently maintained fromother tracks.- Random routes paralleling the OTS 1 or 2 degrees north or south can be as busy as the OTSitself.16.6.11 Dispatchers planning NAT flights originating in south Florida or the Caribbean shouldconsider the effect of traffic from South America operating north eastwards to the USA, when deciding onflight levels. Although the dispatcher should plan optimum flight levels, adequate fuel should be carried sothat a NAT flight can accept a lower altitude (FL260 or FL280) until east of 70 ˚W.16.6.12 Any flight planning to leave an OTS track after the oceanic entry point must be treated as arandom route. The track letter must not be used to abbreviate the route description.16.6.13 Flights operated against the peak traffic flows should plan to avoid the opposite directionOTS. Even if operating outside of the validity periods of the OTS some restrictions on routings may apply.These can affect Eastbound traffic crossing 30W at 1030 UTC or later; and Westbound traffic crossing 30Wat 2400 UTC and later (See Chapter 4, paragraph 4.1.6). If in any doubt it would be prudent to co-ordinateany such routes directly with appropriate OACs.Flight Levels16.6.14 Flight Dispatchers should be aware of the North Atlantic Flight Level Allocation Scheme(FLAS). This is subject to change and the current FLAS is published in the UK and Canadian AIPs andshown at Attachment 6.16.6.15 Chapters 2 and 4 contain details on RVSM flight level guidance. Since virtually all airspaceadjoining MNPS airspace is now RVSM, transition problems are no longer a major issue for ATC ordispatchers. Nevertheless dispatchers should be aware that some “opposite direction” levels, which may beflight planned for the NAT segment of a flight, may not be similarly allowed in adjacent domestic areas.Guidance for RVSM flight procedures in MNPS airspace can be found in Chapter 9 of this Manual.16.6.16 RVSM allows more flight levels for planning and therefore provides better opportunity to flycloser to an optimum route/profile. As aircraft fly towards their destination they become lighter as fuel onboardis consumed and they are then able to climb to more fuel efficient altitudes. It is acceptable to planand/or request step climbs within the OTS but because of traffic volumes and the difference in aircraftperformance it is wise to plan conservatively. Climbs on random routes that are totally north or south of thetrack system are more readily approved. If a flight is planned without profiling a climb crews should beencouraged to request a climb as aircraft decreasing weight permits.Communications16.6.17 The availability of functioning HF ATS communications is mandatory for flights through theShanwick OCA. Many States of Registry insist on two functioning long range communications systems forflights in Oceanic or Remote areas. Some States of Registry will allow their operators to substituteSATCOM Voice for one HF system. Dispatchers should ensure that they are fully aware of their State ofRegistry requirements in this regard. VHF communications (freq 123.45 or 121.5) can be used as to relayair-ground ATS communications as backup in case of en route HF failure.16.6.18 Many operators now use ADS-C (automatic dependent surveillance) and CPDLC (controllerpilot data link communications) for oceanic position reporting and clearance updating. These featuresimprove position reporting speed and accuracy. They also reduce the chance of errors. Advancedregistration with the ATS Providers may be required if ADS/CPDLC are to be used in the NAT Region.NAT Doc 007 97 Edition 2010