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Miscellaneous

•FLIGHT INFORMATION AND METEOROLOGICAL SERVICES. Frequencies for ATIS, Flight Information Service and Weather Information are provided within various Flight Information Regions (FIR) at nominated centres, at the inset chart bottom left of the main chart.

•GENERAL AVIATION FORECAST AREAS are shown in the adjacent chart. The numbers refer to telephone numbers.

•Note the AIRSPACE CLASSIFICATION GERMANY diagram and table. Only class C, D, E, F and G are used in Germany.

•Note the PHONETIC ALPHABET AND MORSE CODE.

• Note the SEMI-CIRCULAR CRUISING LEVELS ON VFR FLIGHTS and those for France.

•VFR ROUTES WITHIN FRANCE. Bearings and tracks are magnetic and distances are in nautical miles.

•Note the table of AIRSPACE DESIGNATORS AND CONTROL FREQUENCIES.

Example 3

Give a complete decode of the airfield information at Augsburg.

Example 4

Decode the blue triangle to the east of Augsburg.

Example 5

Decode the navaid information at N4843.2 E01131.3 and N4844.3 E01138.7.

Example 6

What does the symbol at N4822.9 E00838.7 signify?

Example 7

What type of airspace is Salzburg VOR/DME within? Give its dimensions.

Example 8

What are the Salzburg ATIS and Weather Broadcast frequencies?

Answers to Examples 3 to 8 can be found on page 141

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				Establishment of Minimum Flight Altitudes
				(Ref. EU-OPS 1.250)
				When selecting a Flight Altitude/Level which gives adequate clearance for a given sector the
				following should be considered:
				• The accuracy with which an aircraft can determine its position.
				•	The inherent inaccuracies of altimeters and their indications plus corrections required to
					account for temperature and pressure variations in relation to ISA.
				• The characteristics of the terrain.
				• Rotor turbulence and standing waves.
	9
	ChartTopographical			• The accuracy of the navigational chart.
				•	The vertical extensions of the types of airspace.
				•	The vertical extensions of Danger, Restricted and Prohibited areas. (Avoid them if they

cannot be overflown).

• The highest ground or obstacle within the promulgated distances either side of the planned track.

• The ICAO Standard Semi-circular Cruising Levels. (See Figure 9.1)

The Minimum Grid Area Altitudes (Grid MORA)

These are printed on the chart have already been referred to. These could be used:

•As a rapid means of assessing the appropriate Flight Level/Altitude.

•As a means of cross-checking terrain clearance values that have been obtained using the stated methods.

•As a rapid means of re-assessing safe clearance of terrain, e.g. when a pilot becomes unsure of his exact position in relation to his intended track.

Students will be required to find the highest obstacle within a given distance either side of track. Normally the distance will be 5 NM either side of track

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Choosing Cruising Levels

(See Figure 9.1 and bottom of the chart)

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Figure 9.1 ICAO semi-circular cruising levels

The choice of safe Flight Level is determined by the aircraft’s planned Magnetic track (not heading), stated obstacle clearance allowance and regional forecast route QNH. For VFR flight for SEP and MEP aircraft the BELOW FL290 VFR diagram, top right of Figure 9.1, is the reference. Flight Levels for a track between 0°M and 179°M are odd levels plus 500 ft; for tracks between

180°M and 359°M they are even levels plus 500 ft.

(When choosing levels for the Medium Range Jet Transport (MRJT) aircraft, the IFR BELOW FL290 and AT AND ABOVE FL290 will be the reference for IFR flight).

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Altimeter Errors and Corrections

An altimeter is calibrated in relation to the International Standard Atmosphere (ISA).

A mean sea level pressure and temperature of 1013.25 hPa and +15°C, and a mean temperature lapse rate of 2°C (1.98°C)/1000 ft up to 36 090 ft, where it remains constant at -56.5°C.

Thus, when calculating the height increment/decrement in feet from an airfield to an aircraft’s Flight Level (pressure altitude), which is based upon the above standard conditions, the differences in pressure and temperature between the actual and ISA conditions must be accounted for.

Pressure Difference

The initial pressure setting for take-off will be QNH, which when set on the altimeter subscale causes it to indicate the aircraft’s altitude (airfield elevation) above mean sea level at take-off, disregarding instrument error.

On passing the transition altitude the standard pressure setting of 1013.25 hPa is set on the altimeter subscale. The difference between 1013.25 hPa and the airfield QNH will result in a barometric error, height loss or gain, in the order of 30 ft/hPa.

Figure 9.2 1013.25 hPa > QNH - less height gained

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Figure 9.3 1013.25 hPa < QNH - more height gained

Temperature Difference from ISA at Cruising Pressure Level

The standard temperature for an aircraft flying at FL85, for example, is - 2°C. If the Corrected Outside Air Temperature (COAT) is -15°C the aircraft is flying in air colder and denser than standard; as pressure decreases more rapidly in a column of colder air the altimeter will over read. Conversely, when the COAT is warmer than standard the air is less dense and the altimeter will under read. Therefore when 1013.25 hPa is set:

LOWER COAT - altimeter OVER READS

HIGHER COAT - altimeter UNDER READS

The “ALTITUDE” window on the reverse of the CRP5 is used to correct for the difference in temperatures. Using the CRP5:

Set FLIGHT LEVEL (85) against COAT (-15°C) in the “ALTITUDE” window; read off TRUE ALTITUDE (8100) in feet on the OUTER SCALE against FLIGHT LEVEL (85) on the INNER SCALE. Thus the altimeter is over reading by 400 ft.

If FL85 had been chosen to provide a 1000 ft clearance above an obstacle at 7500 ft AMSL within the stated limits on the aircraft’s planned sector, then the actual clearance would be 600 ft. A safer level to accord with ICAO VFR Semi-circular Cruise Levels would thus be FL105.

Consider an aircraft flying at FL75 (ISA 0°C), with a COAT of +16°C:

Set FLIGHT LEVEL (75) against COAT (+16°C) in the “ALTITUDE” window; read off TRUE ALTITUDE (7925) in feet on the OUTER SCALE against FLIGHT LEVEL (75) on the INNER SCALE. The altimeter will under read by 425 ft:

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In this instance FL75 was chosen to provide a clearance of 1000 ft above an obstacle of 6500 ft AMSL. The actual clearance is thus 1425 ft.

Hence remember the adage in relation to temperature (and pressure):

“High to low mind how you go”

Example 9

An aircraft is airborne from an airfield, elevation 800 ft, on a track of 090°(M); QNH 996 hPa.

a.What VFR Flight Level must the aircraft maintain in order to clear an obstacle, 4400 ft AMSL, by 1000 ft?

b.What height is climbed to this Flight Level?

Answers can be found on page 141

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