Questions

Exercise 2

(Use NCP chart)

“ACA865 is cleared to Toronto via North Atlantic Track Echo from 55N 010W to maintain FL320, Mach. 82.” The forecast wind velocity and COAT at FL320 are 020°/110 kt and -60°C.

Plot the part-route:- London, N55 W010, N57 W020 and N57 W030, and answer the following: (Tolerances for distances within 1%)

1.	The route distance London to N57 W030 is	.................
2.	The mean Great Circle track London to N57 W030 is .............		(T)
3.	The mean magnetic variation N55 W010 to N57 W020 is .............
4.	The mean Great Circle track N57 W020 to N57 .............W030 is		(T)
5.	The initial heading from N55 W010 is ............	(M)

6.The aircraft’s ATA at N55 W010 is 1038Z. The ETA at N57 W020 is ..............

7.The aircraft’s ATA at N57 W020 is 1126Z. The ETA at N57 W030 is ..............

8.The aircraft is cleared to be at N57 W030 at 1211Z. Its revised Mach No. is ...............

The aircraft’s ATA at N57 W030 is 1211Z. At 1201Z Gander Oceanic re-clears the aircraft from N57 W030 to N55 W040 at FL320, Mach .82. The forecast wind velocity and COAT are 350°/90 kt and -64°C. Answer questions 9 and 10.

9.	The mean Great Circle track and distance from N57 W030 to N55 W040 are .............				(T)
	and ..............
10.	The ETA at N55 W040 is	.............
11.	At CARPE (N5305.0 W05405.0) the aircraft leaves the .....................			CTA /.................	FIR
	and enters ......................	CTA/....................	FIR.
12.	The distance from CARPE to REDBY (N5215.0 W05636.1) is ...............			NM.

13.What does RVSM means?

14.What does MNPS means?

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Questions 11

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11 Answers

Answers - Exercise 2

	1.		1087 NM.
	2.		288°(T).
	3.		12°W.
	4.		270°(T).
	5.		318°(M).
	6.		1126Z.
	7.		1206Z.
	8.		Mach .72.
11	9.		250°(T); 358 NM
Answers	10.		1256Z.
	11.		GANDER OCEANIC CTA/CZQX; GANDER DOMESTIC CTA/CZQX.
	12.		103 NM.
	13.		Reduced Vertical Separation Minima.
			(The equipment required is two fully serviceable independent altitude measurement
			systems; one automatic altitude-control system and one altitude alerting device. A
			functioning Mode C SSR Transponder is also required for flight through radar controlled
			RVSM transition airspace. When checking altimeters, pre-flight or in-flight, at least two
			primary altimeters must agree at all times within plus or minus 200 ft.)
	14.		North Atlantic Minimum Navigation Performance Specification.
			Aircraft must be equipped with the following:
	•	Two fully serviceable Long Range Navigation Systems (LRNS). An LRNS may be one of the
		following:
	• One Inertial Navigation System (INS);
	• One Global Navigation Satellite System (GNSS); or
	• One navigation system using inputs from one or more IRS or any other sensor complying
			with the MNPS requirement.
	•	Each LRNS must be capable of providing to the flight crew a continuous indication of the
		aircraft position relative to track.
	•	It is highly desirable that the navigation system employed for the provision of steering
		guidance is capable of being coupled to the auto-pilot.

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Airways - Miscellaneous Charts 11

North Atlantic & Central North Atlantic

Blow-up Plotting Chart - Introduction

Both charts are Lambert Conical Conformal projections designed for:

•ETOPS. (This chart has been produced for an Airbus 330.)

•EQUAL TIME POINT(ETP)/CRITICAL POINT (CP) calculation and plotting.

•Position and route plotting.

The NORTH ATLANTIC PLOTTING CHART has a scale of 1 inch = 200 NM; its bottom right-hand corner contains an EQUAL TIME POINT (ETP)/CRITICAL POINT (CP) graph with instructions for its use.

On the obverse is the CENTRAL NORTH ATLANTIC BLOW-UP AREA

Scale 1 inch = 120 NM.

The ETP graph and instructions apply to this chart also.

North Atlantic & Central North Atlantic

Blow-up Plotting Chart - Range and Time Circles

Both	charts show still air range/time circles of 820 NM/120 MIN (410 kt TAS) and
1220	NM/180 MIN (406 kt TAS) centred upon suitable diversion airfields such as Shannon

(EINN), Lajes (LPLA), Gander (CYQX) and Keflavik (BIKF). These airfields are open 24 hours a day and can provide appropriate facilities for all types of aircraft.

Airways - Miscellaneous Charts 11

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Questions 11

Questions

Example 4

On the CENTRAL NORTH ATLANTIC BLOW-UP AREA chart:

a.Plot the route:

Shannon (EINN) N5242 W 00855, to Gander (CYQX) N4856 W05434, to Keflavik (BIKF) N6359 W02236, to Shannon.

b.Identify the 120 MIN and 180 MIN range circles from each airfield.

c.	The midpoint line cuts the Shannon/Gander track at position ............	and is ............	NM
	from each.
d.	The midpoint line cuts the Gander/Keflavik track at position ............	and is .............	NM
	from each.
e.	The midpoint line cuts the Keflavik/Shannon track at position ...........	and is ............	NM
	from each.

It should be noted that any point on the extended MIDPOINT LINE, either side of the MIDPOINT, will be equidistant from either airfield and will be the STILL AIR ETP/CP.

At 90° to either side of each MIDPOINT LINE is a graticule which is used to adjust the STILL AIR ETP/CP, either in the continuing (ON) or returning (HOME) direction, for the prevailing wind pattern.

Example 5

Use the CENTRAL NORTH ATLANTIC BLOW-UP AREA chart, and the ETP graph when required.

Given:

Route Shannon to Gander at Example 4

Cruise FL310; All-engine TAS 426 kt

Engine-out stabilizing height FL240; Engine-out TAS 370 kt

Wind Components

	MIDPOINT to GANDER	MIDPOINT to SHANNON
FL310	-80 kt	+50 kt
FL240	-40 kt	+20 kt

Calculate the distance and time to the all-engine ETP/CP between Shannon and Gander.

a.	The equi-time number is ...................
b.	The number of miles from the midpoint is .................		NM.
c.	The distance to the ETP/CP from Shannon is ..............		NM.
d.	The time to the ETP/CP is ..................	min.

196

X =

=

=

×

+

............................ NM.

............................ min.

				Questions		11
Cross-check using the formula:
e.	The distance X to the ETP/CP from EINN	=	×
			+
		= ...........................	NM.
f.	The time to the ETP/CP	= ...........................	min.

Example 6

Given:

Route Shannon to Gander at Example 4

Cruise FL310

All-engine TAS 426 kt

Engine-out stabilizing height FL240

Engine-out TAS 370 kt

Wind Components
	MIDPOINT to GANDER	MIDPOINT to SHANNON
FL310	-80 kt	+50 kt
FL240	-40 kt	+20 kt

Using the same chart and route calculate the distance and time to the engine-failure ETP/CP.

a.	The equi-time number is .....................
b.	The number of miles from the midpoint is ..................		NM.
c.	The distance to the ETP/CP from Shannon is ...............		NM.
d.	The time to the ETP/CP is ...................	min.

Cross-check using the formula:

e.The distance from the ETP/CP,

Questions 11

f.The time to the ETP/CP

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