Lateral Offsets (SLOP)
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From: Las Vegas, Nevada
Lateral Offsets (SLOP)
ICAO Doc 4444; §16.5.3
Almost everywhere in the world where SLOP is authorized, this seems to be the case where it is talked about in the respective AIP (or the Jeppesen Airway Manuals). Now, I know from experience that SLOP is permissible in the Pacific on the NOPAC and PACOTS routes, but I can’t find a single official source that states SLOP is permissible in Japanese oceanic airspace. Not in any Jeppesen document, not in the Japanese AIP…
Is there a circular I’m missing or something else I’m completely missing? Someone asked me how do you know where you can apply SLOP, and just giving a blanket statement of “non-radar, remote or oceanic airspace” isn’t always true. There has to be guidance and I’m not finding any. Any help?
Thanks
The routes or airspace where application of strategic lateral offsets is authorized, and the procedures to be followed by pilots, shall be promulgated in aeronautical information publications (AIPs).
Is there a circular I’m missing or something else I’m completely missing? Someone asked me how do you know where you can apply SLOP, and just giving a blanket statement of “non-radar, remote or oceanic airspace” isn’t always true. There has to be guidance and I’m not finding any. Any help?
Thanks
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From: UK
No help but just a comment; In the days before improved IRSs with GPS; aircraft were "scattered" either side of oceanic airways, owing to poorer navigational accuracy - resulting in random lateral offsets. It is the improved accuracy and reliability of laser ring gyro IRSs coupled with GPS that makes track keeping so much more accurate and therefore SLOP sometimes desirable.
If you unofficially applied SLOP of just 1 or 2 nm over the Ocean, who is going to either notice or care? (as long as you remember to cancel the SLOP after the crossing).
If you unofficially applied SLOP of just 1 or 2 nm over the Ocean, who is going to either notice or care? (as long as you remember to cancel the SLOP after the crossing).
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From: FNQ ... It's Permanent!
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From: 500 miles from Chaikhosi, Yogistan
Once in Oceanic Control Area, slop away, up to 2 miles right.
Last edited by compressor stall; 7th September 2022 at 08:52. Reason: ref
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From: 500 miles from Chaikhosi, Yogistan
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From: Seoul/Gold Coast.....
Flying between NZAA-RKSI a small deviation ( less than one mile) around a developing CB near Noumea had Brisbane ATC send a CPDLC message, "Report back on track", Big brother is watching you!
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From: Seattle
Likely because China often assigns a SLOP, so they accommodate incoming traffic from China. Once I had China assign me a 30 mi offset!
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From: Las Vegas, Nevada
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From: South Korea
Here comes the official source
nobody had answered the question so far, so here it goes:
JAPAN AIP ENR 3.5
3.9.2 Offsets are only applied in the oceanic control area over the Pacific Ocean within the Fukuoka FIR.
3.9.3 Offsets are applied only by aircraft with automatic offset tracking capability.
3.9.4 The following requirements apply to the use of the offset:
(1) The decision to apply a strategic lateral offset is the responsibility of the flight crew.
(2) The offset shall be established at a distance in tenths of a nautical mile up to a maximum of 2NM to the right of the center line relative to the direction of flight.
(3) The strategic lateral offset procedure has been designed to include offsets to mitigate the effects of wake turbulence of preceding aircraft.
(4) There is no ATC clearance required for this procedure and, above it is not necessary that ATC be advised.
(5) Voice position reports are to be based on the current ATC route/course clearance and not the exact coordinates of the offset position.
(6) When radar identification is established, pilots shall fly on the centerline.
JAPAN AIP ENR 3.5
3.9 Strategic Lateral Offsets Procedures in Fukuoka FIR
3.9.1 This procedure is to be used for both wake vortex encounters, and to mitigate the heightened risk of collision when non-normal events such as operational altitude deviation errors and turbulence induced altitude deviations occur.3.9.2 Offsets are only applied in the oceanic control area over the Pacific Ocean within the Fukuoka FIR.
3.9.3 Offsets are applied only by aircraft with automatic offset tracking capability.
3.9.4 The following requirements apply to the use of the offset:
(1) The decision to apply a strategic lateral offset is the responsibility of the flight crew.
(2) The offset shall be established at a distance in tenths of a nautical mile up to a maximum of 2NM to the right of the center line relative to the direction of flight.
(3) The strategic lateral offset procedure has been designed to include offsets to mitigate the effects of wake turbulence of preceding aircraft.
(4) There is no ATC clearance required for this procedure and, above it is not necessary that ATC be advised.
(5) Voice position reports are to be based on the current ATC route/course clearance and not the exact coordinates of the offset position.
(6) When radar identification is established, pilots shall fly on the centerline.
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From: Las Vegas, Nevada
nobody had answered the question so far, so here it goes:
JAPAN AIP ENR 3.5
3.9.2 Offsets are only applied in the oceanic control area over the Pacific Ocean within the Fukuoka FIR.
3.9.3 Offsets are applied only by aircraft with automatic offset tracking capability.
3.9.4 The following requirements apply to the use of the offset:
(1) The decision to apply a strategic lateral offset is the responsibility of the flight crew.
(2) The offset shall be established at a distance in tenths of a nautical mile up to a maximum of 2NM to the right of the center line relative to the direction of flight.
(3) The strategic lateral offset procedure has been designed to include offsets to mitigate the effects of wake turbulence of preceding aircraft.
(4) There is no ATC clearance required for this procedure and, above it is not necessary that ATC be advised.
(5) Voice position reports are to be based on the current ATC route/course clearance and not the exact coordinates of the offset position.
(6) When radar identification is established, pilots shall fly on the centerline.
JAPAN AIP ENR 3.5
3.9 Strategic Lateral Offsets Procedures in Fukuoka FIR
3.9.1 This procedure is to be used for both wake vortex encounters, and to mitigate the heightened risk of collision when non-normal events such as operational altitude deviation errors and turbulence induced altitude deviations occur.3.9.2 Offsets are only applied in the oceanic control area over the Pacific Ocean within the Fukuoka FIR.
3.9.3 Offsets are applied only by aircraft with automatic offset tracking capability.
3.9.4 The following requirements apply to the use of the offset:
(1) The decision to apply a strategic lateral offset is the responsibility of the flight crew.
(2) The offset shall be established at a distance in tenths of a nautical mile up to a maximum of 2NM to the right of the center line relative to the direction of flight.
(3) The strategic lateral offset procedure has been designed to include offsets to mitigate the effects of wake turbulence of preceding aircraft.
(4) There is no ATC clearance required for this procedure and, above it is not necessary that ATC be advised.
(5) Voice position reports are to be based on the current ATC route/course clearance and not the exact coordinates of the offset position.
(6) When radar identification is established, pilots shall fly on the centerline.
