Results
#1. MSA given as 12,000ft, flying over mountains in temperatures +9°C, QNH set as 1023 (obtained from a nearby airfield). What will the true altitude be when 12,000ft is reached?
- TRUE ALTITUDE = ALTITUDE ON QNH (ISA DEVIATION x 4 x PRESSURE ALTITUDE ÷ 1000)
Alt on QNH = 12000ft
Isa deviation = 18 ( supposed to be -9 but it is 9)
Ta =[12000 ( 18x4x12000) ] /1000
Ta = 12864
#2. The lowest temperature in the international standard atmosphere (ISA) is?
The ICAO ISA is defined as follows:-
a MSL temperature of 15°C
a lapse rate of 0.65°C/100m (1.98° C /1000 ft) up to 11 km (36,090 ft)
a constant temperature of –56.5°C from 11 km (36,090ft) to 20 km (65,617 ft)
after which the temp increases with height ( inversion).
hence lowest is -56.5°C
CONVERT THE ANSWER IN KELVIN
273 (-56.5) = 216.5°K
#3. Which frontal or occlusion system is the fastest moving?
#5. From the pre-flight briefing you know a jet stream is at 31000 ft whilst you are at FL270. You experience moderate C.A.T, what would be the best course of action?
#6. In the Northern Hemisphere a man observes a low pressure system passing him to the south, from west to east. What wind will he experience?
#7. On a significant weather chart you notice a symbol with the letter “H” and the number “400” inside. What does this imply?
#8. When would a rotor cloud be ahead of a Cb?
Above picture shows mature stage
roll cloud are also rotor clouds
#9. You are at 12,000 ft (FL120) with an outside air temperature is -2°C. Where would you find the freezing level?
#10. What are the conditions under which advection fog will be formed?
#11. How does a polar front depression normally move?
#12. What cloud does hail fall from?
#13. Flying away from a low pressure at low levels in the Southern Hemisphere, where is the wind coming from?
#14. What is a cold pool, in the northern hemisphere?
These are outbreaks of cold air from near the poles. These outbreaks are usually characterized by a cold front at their leading edge. In fact they are common just behind the polar front depressions behind the cold front itself. Typically the air is unstable and therefore expect cumuliform activity with showers and even thunderstorms.
#15. The ITCZ in July is?
#16. What is Relative Humidity dependent upon?
Relative Humidity is a term used to describe the quantity of water vapour that exists in a gaseous mixture of air and water. Relative humidity is expressed as a percentage and is calculated using the formula below. More simply, the relative humidity is the amount of water vapour present in a volume of air divided by the maximum amount of water vapour which that volume could hold at that temperature expressed as a percentage.
#17. Using the diagram shown, what cross section is through an occluded front?
#19. What is true about the dew point temperature?
#20. Where are you most likely to find moderate to severe icing?
Rain ice occurs in a narrow range of altitudes at low level, about 1000 ft, ahead of a warm front or occlusion and is associated particularly with the moderate continuous rain which often falls from Nimbo Stratus cloud
#21. What kind of weather system might you typically find between the 45° – 70°N?
#22. Height of the tropopause at 50° N
#23. What is true regarding super cooled water droplets?
#24. What are the indications of a TRS from a great distance?
#25. What is most different about the Equatorial Easterly jet stream?
#26. Flying from London to Bombay in January, what average wind might you expect?
The direction of jet streams is generally westerly, maximum speeds occur near the tropopause, 200 kts have been recorded in Europe/N Atlantic and 300 kts in Asia.
hence westerly would be prominent
we will not encounter polar jet stream as we are not going towards the pole
#27. Flying towards a warm front, at what distances might you expect the following cloud types from the surface position of the front?
#28. What pressure systems affect the North Atlantic in summer?
North American or Canadian Low replaces Winter High. Icelandic “Statistical” Low 1010 mbs. Less deep and split. Azores High 1025 hPa intensified. Further North at 35°N. Hurricanes in Caribbean and Florida area.
#30. Wind is caused by?
#31. What weather might you expect behind a fast moving cold front?
#32. How do you recognise high level jet streams and associated CAT?
From the ground, when the cloud amounts allow, jets may be recognised by wind blown wisps of CIRRUS cloud blowing at right angles to the clouds at lower levels.
#33. How would an unstable atmosphere likely reduce the visibility?
#35. Which is true regarding a polar front jet stream?
#36. Where is the coldest air in a cold occlusion?
#37. Which of the following indicates upper level instability and possible the formation of TS?
#38. What causes low level cloud in front of the warm front?
.
#39. When are the north Atlantic lows at their most southerly position?
#40. Where is the largest chance of squalls occurring?
Squall line with embedded bowing line segments often located along or north of warm front southward across warm sector along or ahead of cold front.
#41. A layer of air cooling at the SALR compared to the DALR would give what kind of cloud?
#42. ELR is 1ºC/100m
The ELR now matches the DALR meaning that dry parcels will be neutral. And no vertical movement
DALR = ELR > SALR.
#43. For the same pressure gradient at 50N, 60N and 40N, the geostrophic wind speed is?
#44. Typical tornado diameter
tornadoes 100m to 150 m
#45. What is a SPECI?
#46. In the area of the ITCZ why are the heights of the tropopause not reported?
the trade-winds converge and air rises high into the upper reaches of the “troposphere.”
The strong updraft in the ITCZ raises the tropopause, the upper boundary of the troposphere, to about 15 km height
#47. A parcel of air cooling by more than 1°C/100m is said to be?
#48. Flying condition in Ci cloud and horizontal visibility
#49. The wind in the Northern Hemisphere at the surface and above the friction layer at 2000 ft would be?
#50. Description of radiation fog
#51. Where are easterly and westerly jets found?
#52. Flying over an airfield, at the surface the temp is -5ºC, freezing level is at 3000ft, rain is falling from clouds with a base of 4000ft caused by warm air rising above cold air. When would you experience icing?
met reports inversion warm air rising ( increase in temp with height)
-5° at ground then 0° level will be just above
hence
Yes, between ground level and 3000 FT/AGL
#54. Climbing out of Dhahran, Saudi Arabia on a clear night you suddenly lose your rate of climb. Why?
Vertical windshear is change in wind velocity with height. It is typically measured in knots per 100ft. This type of windshear is very common during an inversion, therefore expect them at night and in well developed high pressure systems such as those found under the sub tropical high pressure belt. As an aeroplane fly’s through an inversion, not only will the change of temperature cause the engine performance to change, but the abrupt change in wind speed and direction may significantly alter the flight path.
#55. At 15,000ft in nimbostratus cloud with an outside air temperature of -12°C, what icing might you expect?
#56. What is the composition of Ci cloud?
#57. Comparing rain to drizzle, visibility will generally…?
#58. What cloud types are classified as medium cloud?
#59. What statement is true regarding the tropopause?
#60. What is the approximate height of the tropopause at 50ºN?
#61. Isolated TS occur mostly due to
Heat, or airmass type (more common in summer time).
Also called isolated
are formed by thermal triggering or CONVECTION
not by frontal uplift
#62. Please refer to Appendix F (attached on the next page) What is the temperature deviation, in degrees Celsius, from the International Standard Atmosphere overhead Frankfurt (50N 08E) at FL 180 ?
#63. Polar front depression normally move
#64. What type of cloud is associated with drizzle?
Stratus (from Latin stratum, meaning strewn) is generally a grey, layered cloud with a fairly uniform base, which may produce drizzle, or light snow. Stratus cloud is no more than 1,000 – 1 500 ft thick, and is often much thinner. Stratus is usually the lowest of all cloud types.
#65. QNH in a METAR is
#66. Fair weather cumulus gives an indication of
#67. Thermal lows usually develop
#68. What cloud type are you least likely to get icing from?
#69. TAF’s are usually valid for
#70. When flying from South to North in the Southern Hemisphere crossing over and above a polar frontal jet at FL 400, what might happen to the OAT?
PFJ ARE LOCATED IN WARM AIR
#71. Tornadoes are usually associated with which cloud type
#72. What type of jet stream blows constantly through the northern hemisphere?
Sub tropical jetsteams form in the area of the sub-tropical anti-cyclones. They are more or less permanent but move seasonally with the sub-tropical highs. They occur in the latitude bands 25° to 40° in winter and 40° to 45° in summer. The jet core is at the 200 hPa level.
#73. Wind at altitude is usually given as …….. in ……..
#74. Why is clear ice such a problem?
can be very dangerous. There can be much flowback and the ice appears transparent because there is no air trapped under the flowback icing. The lamination of the ice into layers increases its strength and because it has less air in it this type of ice is much stronger and much harder to remove.
The ice will destroy aerofoil shapes and its weight can cause problems of control because the build-up can be uneven.
Propeller icing can cause severe vibrations and as the ice adheres strongly, when it breaks off, the pieces can be large and cause skin damage.
#75. The surface wind circulation found between the sub tropical highs and the equatorial lows are called?
#76. What best shows Altocumulus Lenticularis?
Altocumulus lenticularis, also known as lenticular cloud, is found downwind of mountainous or hilly areas, and is indicative of the presence of mountain wave activity. Because of its position downwind of high ground, moderate or even severe turbulence may be found beneath altocumulus lenticularis.
#77. An occlusion is mimicking a cold front, where would the coldest air be found?
#78. A steep pressure gradient is characterised by
Closely spaced isobars imply a steep pressure gradient (common in low pressure systems) and widely spaced isobars imply a shallow pressure gradient (common in high pressure systems).
#79. In a high pressure systems
#80. Assuming a generalised zonal distribution of winds, which zones on the diagram contain the temperate lows?0
#81. Over flat dry land what would cause cloud?
#82. If you fly with left drift in the Northern Hemisphere, what is happening to your true altitude?
Buys Ballot’s Law states that: If an observer stands with his back to the wind, the lower pressure is on his left in the northern hemisphere, and on his right in the southern hemisphere.
A corollary of this law is that if an aircraft is experiencing starboard drift in the northern hemisphere the aircraft is heading towards low pressure
in this case the drift is to the left ( port) hence heading towards high pressures
True altitude in High pressure or warm atmosphere is always more than cold/low ,
#83. Where does freezing rain come from?
#84. What type of icing requires immediate diversion?
#85. Without the ability to de-ice or land immediately, what should you do if you encounter rain ice at about 2,000ft?
#87. What is the feature W?
#88. Flying from Dakar to Rio de Janeiro, where is the ITCZ in winter?
#89. Using the picture shown above, what will be expected to happen to the surface pressure after the feature Y has passed?
#90. At a stationary front
stationary front is a weather front or transition zone between two air masses (cold and warm), when neither air mass is advancing into the other at a speed exceeding 5 knots at the ground surface.
#91. A man is flying East to West in the Northern Hemisphere. What is happening to his altitude?
#92. In central Europe, where are the greatest wind speeds?
Jet streams ,The direction of jet streams is generally westerly, maximum speeds occur near the tropopause, 200 kts have been recorded in Europe
#93. Sublimation is
Freezing
If the water droplet is cooled below zero, then it may change state again to ice.
Melting
The opposite change of state, from solid to liquid, is called melting
Sublimation/Deposition
Sublimation is the change of state directly from water vapour to ice without water droplets being formed. Latent heat is released. This process is also known as deposition.
The change of state from ice directly to water vapour is also called sublimation.
#94. Up to FL180 ISA Deviation is ISA -10°C. What is the actual depth of the layer between FL60 and FL120?
#95. In central Europe in summer, under the influence of a polar depression in a wide warm sector, you would expect the following wx:
#96. Standing in the Northern Hemisphere, north of a polar frontal depression travelling west to east, the wind will
#97. An Easterly wave will produce:
#98. What is the coldest time of the day?
As per diurnal variation of temperature
From 15:00 LMT onwards, the temperature falls continuously until a little after sunrise. The lowest temperature occurs at about sunrise plus 30 minutes. (TMIN)
#99. The line connecting A to B crosses what pressure system:
#100. Which of the following would lead to the formation of Advection fog
#101. Which coast of the USA is affected by the most frequent hurricanes:
#103. Flying over France at dawn, with 8/8 St at 200ft, QNH 1026, wind Var3, what will be the most likely conditions at mid-day in winter and summer:
#104. Which of the following would lead to the formation of Steaming fog
Steaming fog, or as it is sometimes called, Arctic Smoke, occurs over sea in polar regions, eg the fjords of Greenland, Iceland and the sea areas of high latitudes. It is caused by cold air from a land mass moving over a warmer moist surface or sea. The small amount of evaporation from the sea is enough to cause saturation and condensation but the air itself must be very stable.
#105. What do the following one hour interval METARS indicate the passage of: 22010KT 9999 SCT200 14/08 Q1012= 22010KT 9999 OVC200 13/08 Q1011= 23012KT 9KM SCT 060 OVC120 13/08 Q1010= 24012KT 8KM -RA BKN040 OVC090 12/08 Q1009= 25015KT 2000 +RA SCT002 OVC008 12/08 Q1008= 27015KT 0800 DZ BKN002 OVC010 17/16 Q1008= 27015KT 0800 DZ BKN002 OVC010 17/16 Q1008= 27015G30KT 1000 +SHRA TS OVC010 17/16 Q1008= 29020KT 9000 SHRA BKN020 14/07 Q1010= 31020KT 9999 SCTO30 13/07 Q1012=
#106. When is diurnal variation a maximum?
wind and cloud cover will cause T max to be reduced and T min to be increased.
WIND: wind will cause turbulent mixing of the warm air at the surface with cold air above, reducing T max.
CLOUD: the solar radiation is reflected back by the cloud tops
#107. Paris reports OVC 8/8 St at +3 ° C during the day. What will happen on the night of 3/4 Jan
#108. QNH at Timbuktu (200m AMSL) is 1015 hPa. What is the QFE? (Assume 1 hPa = 8m)
#109. With a cold front over the North Sea, what weather would you expect 300km behind the front?
#110. The Arctic Jet core is at:
Arctic Jet Stream: In winters, long polar night cools the polar air forming an arctic air mass between (roughly) 70 deg latitude and poles. The temperature difference between polar and arctic air causes arctic jet stream. The core is at 20,000 feet and max speed around 80 knots.
#111. Surface wind is 320/12 what is the wind at 2000ft in the Northern hemisphere?
#112. If flying cross country at FL50 you first see NS, AS, CC then CI, you can expect:
Warm front approach with cold air ahead
#113. Lucarno airfield elv 1735 ft altimeter indicates 1310 ft with 1013hPa set what is the QNH?
#114. Which is likely to cause aquaplaning?
Aquaplaning, also known as hydroplaning, is a condition in which standing water, slush or snow, causes the moving wheel of an aircraft to lose contact with the load bearing surface on which it is rolling with the result that braking action on the wheel is not effective in reducing the ground speed of the aircraft.
RA is heavy rain
#115. Where is the ITCZ in July?
#116. Prevailing winds in North West. Africa will be
winter north easterly winds
summer sw monsoon
#117. The letters NC used at the end of a SIGMET, mean:
#118. ATC will only report wind as gusting if:
as per icao annex 3
Annex 3
4. OBSERVING AND REPORTING OF METEOROLOGICAL ELEMENTS […]
4.1 Surface wind […]
4.1.5 Reporting […]
4.1.5.2 In local routine and special reports and in METAR and SPECI: […]c) variations from the mean wind speed (gusts) during the past 10 minutes shall be reported when the maximum wind speed exceeds the mean speed by:
- 2.5 m/s (5 kt) or more in local routine and special reports when noise abatement procedures are applied in accordance with paragraph 7.2.6 of the PANS-ATM (Doc 4444); or
- 5 m/s (10 kt) or more otherwise […]
#119. On the route London to Bombay, which feature would you most likely encounter between 30E and 50E
#120. Hill fog will be most likely when:
#121. When would the strongest convection occur?
#122. In temperate latitudes in summer what conditions would you expect in the centre of a high pressure system?
High pressure area are related to bad visibility and good weather
#123. Which way does a depression move?
#124. Above a stable layer in the lower troposphere in an old high pressure system is called:
a high pressure system, air descends at the centre. As the air descends it will be heated adiabatically (more of this later) and will be warmer than the air at a lower level adjacent to the surface. This is called a Subsidence Inversion.
#125. If the pressure level surface bulges upwards, the pressure system is a:
Pressure level will bulge upwards in high pressure or warm air mass and other way in a low or cold
#126. Freezing rain is most likely from
#127. With regard to RVR and Met vis
#128. What is a land breeze?
After sunset. The land will cool rapidly whilst the sea will retain its heat. There will be an increase in pressure at the surface over the land whilst the pressure over the sea will fall – there will be a land breeze. The speed will be about 5 kts and the breeze will extend about 5 nms out to sea.
#129. When are thermal lows most likely
#130. When travelling from Stockholm (55N 18E) to Rio de Janeiro (22S 80W), do you encounter:
rio is located at 23° s
stockholm at 59° n
will cross polar and few stj as per the diagram
#131. What is the validity of a significant weather chart
#132. Why does air cool as it rises?
a parcel of air was forced to rise in the atmosphere, the decreasing ambient pressure would cause the parcel to expand, much like an air bubble does when it rises through a champagne glass. As the air rises and expands, it will cool adiabatically.
#133. What is the main feature of the initial stage of a thunderstorm
#134. When flying at FL180 in the Southern Hemisphere you experience a left crosswind. What is happening to your true altitude if indicated altitude is constant?
In N hemisphere
Starboard drift= flying into low pressure
Port drift= flying into high pressure
In S hemisphere
Starboard drift= flying into high pressure
Port drift= flying into low pressure
Ac gets starboard drift due to winds from left
Starboard drift
Ac is flying into high pressure
When flying from
Low to high altimeter will under-read
Hence it is under reading the altitude in actual it has increased
#135. What is haze?
#136. In a polar front jet stream in the Northern Hemisphere, where is there likely to be the greatest probability of turbulence?
Polar front jetstreams form in the polar front region in both hemispheres ,in southern around 50° S and near any front which is separate from the polar front.
The upper winds will blow such that looking downstream the cold air will be to the left hand side in northern hemisphere and to the right hand side in the southern hemisphere.
Clear air turbulence (CAT). occurs around the boundaries of jet streams because of the large horizontal and vertical windshears. It is strongest near to, or just below, the jet axis on the cold air (low pressure) side with a secondary area above the axis.
#137. On the chart below, where is rain least likely
#138. Dew point is defined as:
The dew point or dewpoint of a given parcel of air is the temperature to which the parcel must be cooled, at constant barometric pressure, for the water vapour component to condense into water. The dew point of unsaturated air decreases by approximately 0.5°C per 1,000 ft
The dew point is associated with the relative humidity. A high relative humidity indicates that the dew point is closer to the current air temperature.
#139. On a flight from Zurich to Rome, which of the following METARS would be applicable?
#140. Flying from Marseilles (QNH 1012) to Palma (QNH 1015) at FL100. You dont reset the altimeter, why would true altitude be the same throughout the flight?
Ac is flying into high pressure
When flying from
Low to high altimeter will under-read
but True altitude is same
The true altitude of this surface will depend on the density of the air below flying from marseille where the qnh is lower to Palma where the qnh is higher you would normally expect your true altitude to increase since true altitude remains constant it must be colder in Palma
#141. Which of the following is true about freezing precipitation?
#142. FL180, Northern Hemisphere with a wind from the left, what can you say about temperature with a heading of 360°?
With your back to the upper wind, the cold air is to your left in the northern hemisphere and to your right in the southern hemisphere.
if nose to hdg 360° Wind from left then
north is cold
#143. What do the letters NO SIG mean at the end of a METAR
#145. What is a trend forecast
#146. How do you define convection?
Air heated by conduction will be less dense and will therefore rise. This will produce up currents called thermals or convection currents. These currents will help to transfer heat to different parts of the atmosphere. For example, warm air will rise to the upper levels, thus helping to heat the upper atmosphere.
#147. How does clear ice form?
supercooled water droplets
Glaze ice or clear ice is formed when LARGE supercooled drops spread over wings
rime ice is formed WHEN SMALL supercooled drops spread over wings
both happen under 0° Celsius flying through clouds
#148. In a class A aircraft if you encounter freezing rain, do you:
Always fly to the warmer layer, be it above or below
#149. Where is windshear the greatest?
#150. When heading South in the Southern Hemisphere you experience Starboard drift:
With your back to the upper wind, the cold air is to your left in the northern hemisphere and to your right in the southern hemisphere.