Navigation/Atlantic Airspace/RVSM

Question 1

What areas are MNPS Airspace and between what levels in regards to North Atlantic?

Answer 1

Minimum Navigation Performance Specification Established between FL285-FL420. Covers oceanic traffic in Reykjavik, Shanwick, Gander, Santa Maria and New York. Minimum levels of Nav Equipment are required.

Question 2

What is the lateral separation in MNPS airspace?

Answer 2

Generally 1 degree of latitude so 50-60nm (gentle slope rules permit a reduction to no less than 50nm in far north). RLatSM tracks are separated by 1/2 deg or 25nm. Outside MNPS separation 90nm.

Question 3

What are Scheduled Navigation Areas/Specified Areas and where would you find information about them?

Answer 3

OMC 3 - Specified Areas lettered from A-L defined by rhumb lines between co-ordinates. Examples would be S America, N Atlantic Ocean, S Atlantic Ocean, Canada etc. Depending on the Area of operation certain navigation equipment must be carried.

Question 4

Where would you find what equipment should be carried within a MNPS Specified Area?

Answer 4

Tables in OMC 3 for different a/c types.

Question 5

For the 777, what Nav Equip would permit it to operate in all the Specified Areas?

Answer 5

x2 LR Nav (is an FMC, an ADIRU or Alternate Nav system), x1 VOR, x1 DME, x1 ADF

Question 6

Are there any exceptions to the minimum navigation equipments specifications in a Scheduled Area?

Answer 6

Yes, on certain specified routes in the OMC a lower specification may be carried.

Question 7

Between what levels might you be assigned Reduced Lateral Separation minima and what requirements are there in terms of aircraft equipment and route programming?

Answer 7

OMC 8 - Available only btwn FL350-390 in NAT OTS (see RlatSM on My Learning Academy). A/c must be RNP 4/ADS-C/CPDLC. All routes MUST be uplinked either via CPDLC or from BA at commencement of flight. MANUAL ENTRY OF A HALF DEGREE WAYPOINT IS NOT PERMITTED. Longitudinal separation may be reduced to 5 mins. Rlat tracks should be underlined in CIRRUS OTS message

Question 8

What is the longitudinal separation in MNPS airspace?

Answer 8

Varies depending on jet/prop, but generally 10mins on same track/same point on route which may reduce to 5mins at entry point if Mach.06 or greater differential speed and 15mins for crossing traffic.

Question 9

What is ‘different’ about Atlantic RNP4 airspace and what additional equipment is required as opposed to other PBN criteria?

Answer 9

Unlike other PBN areas, the Atlantic PBN also requires ADS-C (indicated by L1 in flight plan) and datalink comms - CPDLC. Essentially it permits a/c to operate within airspace with reduced lateral/longitudinal separation (incl RLatSM tracks in NAT OTS).

Question 10

Within what areas should RNP 4 be default?

Answer 10

Essentially all North Atlantic Control Area -Reykjavik, Shanwick, Gander, Santa Maria and New York (also certain STAR/SID though RNAV STAR generally RNP 1.0.)

Question 11

What Navigation/Communication systems should you check prior to entering RNP 4?

Answer 11

Check FMS default RNP and adjust if required (FMC>PROG PG4), CPDLC and ADS-C logged on at least 10mins prior to entry.

Question 12

What is WATRS airspace?

Answer 12

Western Atlantic Route System. Geographically it extends from set of 60W along the Eastern seaboard of USA across the Caribbean to the north coast of South America and encompasses several FIR’s. It is comprised mainly of fixed routes along airways

Question 13

What is RVSM? What airspace does it encompass and between what levels?

Answer 13

Reduced Vertical Separation Minimum (RVSM) is defined as the reduction of vertical space between aircraft from 2,000 to 1,000 feet at flight levels from 29,000 feet up to 41,000 feet. Covers large proportion of airspace including entire Western hemisphere, Africa, China and Russia.

Question 14

What is the permitted discrepancy between altimeters when entering RVSM airspace?

Answer 14

OMA 8.24.2 - +/- 200ft between primary alt

Question 15

What is time window (earliest/latest) for obtaining an Oceanic Clearance?

Answer 15

90-30 mins. For Santa Maria min of 40mins prior to boundary.

Question 16

How is New York Oceanic different in terms of clearance?

Answer 16

OMC 8.7.1.1. - Only gives altitude and speed. The route will be the last assigned or if it has not been updated that assigned at time of departure.

Question 17

Can you enter Oceanic Airspace without a clearance?

Answer 17

Yes, except Shanwick OCA. You may enter other OCA’s while awaiting a delayed clearance.

Question 18

What are the weather deviation procedures in oceanic airspace?

Answer 18

In first instance contact ATC. If not possible then within 10nm remain at level assigned, broadcast intentions, turn on all lights. Outside 10nm, once 10nm from track descend/climb 300ft. ROT> dev North descend South climb

Question 19

Where would you find the MNPS waypoint checking procedures and manual RNP entry?

Answer 19

FCOM SP11 > Flight Management, Navigation

Question 20

Where would you find ADS procedures?

Answer 20

FCOM SP5 > Communications and OMC 1.6.2

Question 21

Which Pilot responds to CPDLC messages?

Answer 21

Either. A response is expected within 1 min or send a ‘stand-by’ response. Ensure you ARM any ATC reports before actioning a clearance. Recommended that PM inputs any message for PF to check before sending it.

Question 22

Outline basic contingency actions in OTS/Atlantic airspace.

Answer 22

ANC. Turn off track min 45deg to offset of 15nm. Descend out of track structure (ie below FL285) to maintain a level that differs by 500ft from those normally used. When considering a turn back then select bank angle to 25deg and wind heading through 180 deg. A 15nm fix ring can be establish around a given waypoint as an aiming point. In North Atlantic programming a reciprocal route is relatively straightforward but would not be so easy heading to/from S.America for example.

Question 23

All BA a/c are RVSM capable. What specific equipment does this require?

Answer 23

X2 primary Altimeter (must read within 200ft of each other)
X1 Autopilot
X1 ALT Alert
X1 Transponder

Question 24

Between what levels will you find RVSM airspace?

Answer 24

Between FL290-410. It is mandated on the North Atlantic and flight plan must be designated with ‘W’ at Item 10. This is a legal requirement and should the a/c be dispatched non-RVSM FTD MUST be informed and the flight plan amended.

Question 25

Can a non-RVSM a/c fly in RVSM airspace?

Answer 25

Essentially no, however it may be possible to accommodate an a/c at ATC discretion.

Question 26

What should you do if following system failure your a/c is no longer RVSM compliant?

Answer 26

Inform ATC ASAP. Depending on the reason for non- compliance ATC may permit a/c to continue within RVSM airspace. ATC will arrange 2000ft separation.

Question 27

CPDLC does not work. Can you enter Oceanic Airspace? Can you fly on a NAT track? What alternatives do you have?

Answer 27

CPDLC is not mandated for Oceanic airspace (think back to 747-400!). However, as of Nov 2015 RLATSM has been introduced between FL350-390 on certain NAT tracks. To operate on these tracks between these levels and a/c must be;

1. RNP 4 capable
2. CPDLC must be operational
3. ADS-C capable.

Therefore if your a/c for whatever reasons is not you could flight plan at a level below FL350, consider an alternative track not designated as RLATSM or operate outside the OTS.