METEOROLOGY AND WEATHER SERVICES - ATP 2020

9152. What is the primary cause of all changes in the Earth’s weather?. Variations of solar energy at the Earth’s surface. Changes in air pressure over the Earth’s surface. Movement of air masses from moist areas to dry areas.

9160. Where is the usual location of a thermal low?. Over the arctic region. Over the eye of a hurricane. Over the surface of a dry, sunny region.

9159. What is a feature of air movement in a high pressure area?. Ascending from the surface high to lower pressure at higher altitudes. Descending to the surface and then outward. Moving outward from the high at high altitudes and into the high at the surface.

9157. At lower levels of the atmosphere, friction causes the wind to flow across isobars into a low because the friction. decreases windspeed and Coriolis force. decreases pressure gradient force. creates air turbulence and raises atmospheric pressure.

9176. At which location does Coriolis force have the least effect on wind direction?. At the poles. Middle latitudes (30° to 60°). At the Equator.

9177. How does Coriolis force affect wind direction in the Southern Hemisphere?. Causes clockwise rotation around a low. Causes wind to flow out of a low toward a high. Has exactly the same effect as in the Northern Hemisphere.

9178. Which weather condition is defined as an anticyclone?. Calm. High pressure area. COL.

9178-1. A cyclone is. a hurricane force storm in the Indian Ocean. a tropical depression with sustained winds of 63 knots. a tropical depression with a barometric pressure in the center of the feature that is 35 mb lower than pressure outside the weather feature.

9156. Which area or areas of the Northern Hemisphere experience a generally east to west movement of weather systems?. Arctic only. Arctic and subtropical. Subtropical only.

9233. Summer thunderstorms in the arctic region will generally move. northeast to southwest in polar easterlies. southwest to northeast with the jetstream flow. directly north to south with the low-level polar airflow.

9151. What is a characteristic of the troposphere?. It contains all the moisture of the atmosphere. There is an overall decrease of temperature with an increase of altitude. The average altitude of the top of the troposphere is about 6 miles.

9240. What weather feature occurs at altitude levels near the tropopause?. Maximum winds and narrow wind shear zones. Abrupt temperature increase above the tropopause. Thin layers of cirrus (ice crystal) clouds at the tropopause level.

9209. Which feature is associated with the tropopause?. Absence of wind and turbulence. Absolute upper limit of cloud formation. Abrupt change of temperature lapse rate.

9168. Where is a common location for an inversion?. At the tropopause. In the stratosphere. At the base of cumulus clouds.

9241. Where are jetstreams normally located?. In areas of strong low pressure systems in the stratosphere. In a break in the tropopause where intensified temperature gradients are located. In a single continuous band, encircling the Earth, where there is a break between the equatorial and polar tropopause.

9779. The tropopause is generally found when the free air temperatures are. between -55°C and -65°C. between -40°C and -55°C. colder than -60°C.

9229. Which type clouds may be associated with the jetstream?. Cumulonimbus cloud line where the jetstream crosses the cold front. Cirrus clouds on the equatorial side of the jetstream. Cirrostratus cloud band on the polar side and under the jetstream.

9229-1. When high level moisture is available, cirrus clouds form on the. polar side of the jet stream. equatorial side of the jet stream. acute angle side of the jet stream.

9238. Where do the maximum winds associated with the jetstream usually occur?. In the vicinity of breaks in the tropopause on the polar side of the jet core. Below the jet core where a long straight stretch of the jetstream is located. On the equatorial side of the jetstream where moisture has formed cirriform clouds.

9238-1. The rate of decrease in wind speed from the jet stream core is considerably greater on the. equatorial side. polar side. acute angle side.

9810. Large areas of land. tend to increase temperature variations. do not influence the troposhere. minimize temperature variations.

8710. For a flight to an airport in the vicinity of the coast, land surface cooling means you can expect to encounter. sea breezes. land breezes. a chinook wind.

9165. What term describes an elongated area of low pressure?. Trough. Ridge. Hurricane or typhoon.

9165-1. Low pressure areas are areas of. stagnant air. descending air. ascending air.

9191. What is a feature of a stationary front?. The warm front surface moves about half the speed of the cold front surface. Weather conditions are a combination of strong cold front and strong warm front weather. Surface winds tend to flow parallel to the frontal zone.

9192. Which event usually occurs after an aircraft passes through a front into the colder air?. Temperature/dewpoint spread decreases. Wind direction shifts to the left. Atmospheric pressure increases.

9213. If the winds aloft are blowing parallel to the front,. the front can be expected to move with the upper winds. the winds aloft can be expected to turn at the frontal boundary. the front moves slowly if at all.

9215. Which atmospheric factor causes rapid movement of surface fronts?. Upper winds blowing across the front. Upper low located directly over the surface low. The cold front overtaking and lifting the warm front.

9215-1. Dew point fronts result from. air density differences due to the humidity levels. air density due to temperature. temperatures aloft.

9216. In which meteorological conditions can frontal waves and low pressure areas form?. Warm fronts or occluded fronts. Slow-moving cold fronts or stationary fronts. Cold front occlusions.

9217. What weather difference is found on each side of a “dry line”?. Extreme temperature difference. Dewpoint difference. Stratus versus cumulus clouds.

9227. Where is the normal location of the jetstream relative to surface lows and fronts?. The jetstream is located north of the surface systems. The jetstream is located south of the low and warm front. The jetstream is located over the low and crosses both the warm front and the cold front.

9228. Which type frontal system is normally crossed by the jetstream?. Cold front and warm front. Warm front. Occluded front.

9228-1. Steep frontal surfaces are usually associated with. fast moving warm front. fast moving cold front. dry lines.

9228-2. If a sample of air is forced upward and it is colder than the surrounding air, it. sinks until it reaches denser air. gets energy from surrounding air and remains in place. warms from the surrounding air and rises to expansion.

9776. A jet stream is a narrow, shallow, meandering river of maximum winds extending around the globe in a wavelike pattern with speeds of. 50 knots or greater. 71 knots or greater. 100 knots or greater.

9170. Which term applies when the temperature of the air changes by compression or expansion with no heat added or removed?. Katabatic. Advection. Adiabatic.

9186. Which process causes adiabatic cooling?. Expansion of air as it rises. Movement of air over a colder surface. Release of latent heat during the vaporization process.

9158. Which type wind flows downslope becoming warmer and dryer?. Land breeze. Valley wind. Katabatic wind.

9171. What is the approximate rate unsaturated air will cool flowing upslope?. 3°C per 1,000 feet. 2°C per 1,000 feet. 4°C per 1,000 feet.

9182. What is the result when water vapor changes to the liquid state while being lifted in a thunderstorm?. Latent heat is released to the atmosphere. Latent heat is transformed into pure energy. Latent heat is absorbed from the surrounding air by the water droplet.

9185. What weather condition occurs at the altitude where the dewpoint lapse rate and the dry adiabatic lapse rate converge?. Cloud bases form. Precipitation starts. Stable air changes to unstable air.

9185-1. Adiabatic warming is also described as. chronographic warming. expansional heating. compressional heating.

9185-2. Temperature and radiation variations over land with a clear sky typically lead to. minimum temperature occurring after sunrise. incoming terrestrial radiation peaking at noon. temperature reaching a maximum closer to noon than to sunset.

9187. When saturated air moves downhill, its temperature increases. at a faster rate than dry air because of the release of latent heat. at a slower rate than dry air because vaporization uses heat. at a slower rate than dry air because condensation releases heat.

9154. What feature is associated with a temperature inversion?. A stable layer of air. An unstable layer of air. Air mass thunderstorms.

9923. The stability of an air mass can usually be determined by. the height of the tropopause. measuring the dry adiabatic lapse rate. cloud types and the type of precipitation.

9924. Clouds with extensive vertical development over mountainous terrain are a sign of. a dry adiabatic lapse rate. a stable air mass. an unstable air mass.

9925. Cumulus clouds often indicate. possible turbulence. a temperature inversion. a dry adiabatic lapse rate.

9184. What is indicated about an air mass if the temperature remains unchanged or decreases slightly as altitude is increased?. The air is unstable. A temperature inversion exists. The air is stable.

9188. Which condition is present when a local parcel of air is stable?. The parcel of air resists convection. The parcel of air cannot be forced uphill. As the parcel of air moves upward, its temperature becomes warmer than the surrounding air.

9195. How can the stability of the atmosphere be determined?. Ambient temperature lapse rate. Atmospheric pressure at various levels. Surface temperature/dewpoint spread.

9153. What characterizes a ground-based inversion?. Convection currents at the surface. Cold temperatures. Poor visibility.

9155. When does minimum temperature normally occur during a 24-hour period?. After sunrise. About 1 hour before sunrise. At midnight.

9169. What condition produces the most frequent type of ground- or surface-based temperature inversion?. The movement of colder air under warm air or the movement of warm air over cold air. Widespread sinking of air within a thick layer aloft resulting in heating by compression. Terrestrial radiation on a clear, relatively calm night.

9208. How are haze layers cleared or dispersed?. By convective mixing in cool night air. By wind or the movement of air. By evaporation similar to the clearing of fog.

9206. You are planning a flight to a coastal area which is currently below published weather minimums for the ILS approach due to fog. The winds are forecast to increase to 20 knots from the west at your scheduled arrival time. What weather should you expect?. Surface ice. Advection fog thickening as the winds increase to 20 knots. A low layer of stratus or stratocumulus clouds.

9207. Which conditions are necessary for the formation of upslope fog?. Moist, stable air being moved over gradually rising ground by a wind. A clear sky, little or no wind, and 100 percent relative humidity. Rain falling through stratus clouds and a 10- to 25-knot wind moving the precipitation up the slope.

9207-1. Precipitation induced fog. results from relatively warm rain or drizzle falling through cooler air. results from relatively cooler rain or drizzle falling through warmer air. is usually of short duration.

9207-2. You are approaching an airport to land in 20 minutes. The METAR reports temperature 10°C, dew point 10°C, winds 310/04, scattered clouds and rain. You expect. radiation fog. deepening fog. clearing conditions.

9194. Which condition produces weather on the lee side of a large lake?. Warm air flowing over a colder lake may produce fog. Cold air flowing over a warmer lake may produce advection fog. Warm air flowing over a cool lake may produce rain showers.

9193. What minimum thickness of cloud layer is indicated if precipitation is reported as light or greater intensity?. 4,000 feet thick. 2,000 feet thick. A thickness which allows the cloud tops to be higher than the freezing level.

8723. A flight is scheduled at daybreak. The current conditions are rainy, but conditions are expected to clear. The forecast temperature is 10°C, dew point 10°C, with winds 330° at 5 knots. What weather conditions can you expect?. The conditions are favorable for radiation fog. Dense fog which will deepen during the day. Severe ground icing.

9196. Which weather phenomenon signals the beginning of the mature stage of a thunderstorm?. The appearance of an anvil top. The start of rain at the surface. Growth rate of the cloud is at its maximum.

9197. During the life cycle of a thunderstorm, which stage is characterized predominately by downdrafts?. Cumulus. Dissipating. Mature.

9198. What feature is normally associated with the cumulus stage of a thunderstorm?. Beginning of rain at the surface. Frequent lightning. Continuous updraft.

9203. Why are downdrafts in a mature thunderstorm hazardous?. Downdrafts are kept cool by cold rain which tends to accelerate the downward velocity. Downdrafts converge toward a central location under the storm after striking the surface. Downdrafts become warmer than the surrounding air and reverse into an updraft before reaching the surface.

9200. Where do squall lines most often develop?. In an occluded front. Ahead of a cold front. Behind a stationary front.

9204. What is a difference between an air mass thunderstorm and a steady-state thunderstorm. Air mass thunderstorms produce precipitation which falls outside of the updraft. Air mass thunderstorm downdrafts and precipitation retard and reverse the updrafts. Steady-state thunderstorms are associated with local surface heating.

9205. Which type storms are most likely to produce funnel clouds or tornadoes?. Air mass thunderstorms. Cold front or squall line thunderstorms. Storms associated with icing and supercooled water.

9210. Which type cloud is associated with violent turbulence and a tendency toward the production of funnel clouds?. Cumulonimbus mammatus. Standing lenticular. Stratocumulus.

9214. Which weather condition is an example of a nonfrontal instability band?. Squall line. Advective fog. Frontogenesis.

9706. A severe thunderstorm is one in which the surface wind is. 58 MPH or greater and/or surface hail is 3/4 inch or more in diameter. 50 knots or greater and/or surface hail is 1/2 inch or more in diameter. 45 knots or greater and/or surface hail is 1 inch or more in diameter.

9708. A squall is a sudden increase of at least 15 knots in average wind speed to a sustained speed of. 24 knots or more for at least 1 minute. 22 knots or more for at least 1 minute. 20 knots or more for at least 1 minute.

9708-1. Shear turbulence from a thunderstorm has been encountered. 10 miles from the severe thunderstorm. 15 miles from the severe thunderstorm. 20 miles from the severe thurnderstorm.

9202. Atmospheric pressure changes due to a thunderstorm will be at the lowest value. during the downdraft and heavy rain showers. when the thunderstorm is approaching. immediately after the rain showers have stopped.

9189. Convective clouds which penetrate a stratus layer can produce which threat to instrument flight?. Freezing rain. Clear air turbulence. Embedded thunderstorms.

9199. What is indicated by the term “embedded thunderstorms”?. Severe thunderstorms are embedded in a squall line. Thunderstorms are predicted to develop in a stable air mass. Thunderstorms are obscured by other types of clouds.

9211. A clear area in a line of thunderstorm echoes on a radar scope indicates. the absence of clouds in the area. an area of no convective turbulence. an area where precipitation drops are not detected.

9212. When flying over the top of a severe thunderstorm, the cloud should be overflown by at least. 1,000 feet for each 10 knots windspeed. 2,500 feet. 500 feet above any moderate to severe turbulence layer.

9835. A steady state thunderstorm is associated with. surface heating. weather systems. mature stage.

9139. Which is a definition of “severe wind shear”?. Any rapid change of horizontal wind shear in excess of 25 knots; vertical shear excepted. Any rapid change in wind direction or velocity which causes airspeed changes greater than 15 knots or vertical speed changes greater than 500 ft/min. Any change of airspeed greater than 20 knots which is sustained for more than 20 seconds or vertical speed changes in excess of 100 ft/min.

9220. In comparison to an approach in a moderate headwind, which is an indication of a possible wind shear due to a decreasing headwind when descending on the glide slope?. Less power is required. Higher pitch attitude is required. Lower descent rate is required.

9133. Which INITIAL cockpit indications should a pilot be aware of when a headwind shears to a calm wind?. Indicated airspeed decreases, aircraft pitches up, and altitude decreases. Indicated airspeed increases, aircraft pitches down, and altitude increases. Indicated airspeed decreases, aircraft pitches down, and altitude decreases.

9134. Which condition would INITIALLY cause the indicated airspeed and pitch to increase and the sink rate to decrease?. Sudden decrease in a headwind component. Tailwind which suddenly increases in velocity. Sudden increase in a headwind component.

9135. Which INITIAL cockpit indications should a pilot be aware of when a constant tailwind shears to a calm wind?. Altitude increases; pitch and indicated airspeed decrease. Altitude, pitch, and indicated airspeed decrease. Altitude, pitch, and indicated airspeed increase.

9135-1. Which initial cockpit indications should a pilot be aware of when a constant headwind shears to a calm wind?. Altitude increases; pitch and indicated airspeed decrease. Altitude, pitch, and indicated airspeed decrease. Altitude, pitch, and indicated airspeed increase.

9137. Which wind-shear condition results in a loss of airspeed?. Decreasing headwind or tailwind. Decreasing headwind and increasing tailwind. Increasing headwind and decreasing tailwind.

9138. Which wind-shear condition results in an increase in airspeed?. Increasing tailwind and decreasing headwind. Increasing tailwind and headwind. Decreasing tailwind and increasing headwind.

9141. Which airplane performance characteristics should be recognized during takeoff when encountering a tailwind shear that increases in intensity?. Loss of, or diminished, airspeed performance. Decreased takeoff distance. Increased climb performance immediately after takeoff.

9142. Thrust is being managed to maintain desired indicated airspeed and the glide slope is being flown. Which characteristics should be observed when a tailwind shears to a constant headwind?. PITCH ATTITUDE: Increases. VERTICAL SPEED: Increases. INDICATED AIRSPEED: Decreases, then increases to approach speed. PITCH ATTITUDE: Increases. VERTICAL SPEED: Decreases. INDICATED AIRSPEED: Increases, then decreases. PITCH ATTITUDE: Decreases. VERTICAL SPEED: Decreases. INDICATED AIRSPEED: Decreases, then increases to approach speed.

9166. What is an important characteristic of wind shear?. It is primarily associated with the lateral vortices generated by thunderstorms. It usually exists only in the vicinity of thunderstorms, but may be found near a strong temperature inversion. It may be associated with either a wind shift or a windspeed gradient at any level in the atmosphere.

9201. Where can the maximum hazard zone caused by wind shear associated with a thunderstorm be found?. In front of the thunderstorm cell (anvil side) and on the southwest side of the cell. Ahead of the roll cloud or gust front and directly under the anvil cloud. On all sides and directly under the thunderstorm cell.

9225. Which is a necessary condition for the occurrence of a low-level temperature inversion wind shear?. The temperature differential between the cold and warm layers must be at least 10°C. A calm or light wind near the surface and a relatively strong wind just above the inversion. A wind direction difference of at least 30° between the wind near the surface and the wind just above the inversion.

9701. The horizontal wind shear, critical for turbulence (moderate or greater) per 150 miles is. 18 knots or less. greater than 18 knots. not a factor, only vertical shear is a factor.

9130. What is the expected duration of an individual microburst?. Two minutes with maximum winds lasting approximately 1 minute. One microburst may continue for as long as 2 to 4 hours. Seldom longer than 15 minutes from the time the burst strikes the ground until dissipation.

9131. Maximum downdrafts in a microburst encounter may be as strong as. 8,000 ft/min. 7,000 ft/min. 6,000 ft/min.

9814. Maximum downdrafts in a microburst encounter are strong and may include horizontal winds near the surface as strong as. 34 knots. 20 knots. 45 knots.

9132. An aircraft that encounters a headwind of 40 knots, within a microburst, may expect a total shear across the microburst of. 40 knots. 80 knots. 90 knots.

9140. Doppler wind measurements indicate that the windspeed change a pilot may expect when flying through the peak intensity of a microburst is approximately. 15 knots. 25 knots. 45 knots.

9143. Maximum downdrafts in a microburst encounter may be as strong as. 8,000 ft/min. 7,000 ft/min. 6,000 ft/min.

9144. An aircraft that encounters a headwind of 45 knots, within a microburst, may expect a total shear across the microburst of. 40 knots. 80 knots. 90 knots.

9145. (Refer to Figure 144.) If involved in a microburst encounter, in which aircraft positions will the most severe downdraft occur?. 4 and 5. 2 and 3. 3 and 4.

9146. (Refer to Figure 144.) When penetrating a microburst, which aircraft will experience an increase in performance without a change in pitch or power?. 3. 2. 1.

9147. (Refer to Figure 144.) What effect will a microburst encounter have upon the aircraft in position 3?. Decreasing headwind. Increasing tailwind. Strong downdraft.

9148. (Refer to Figure 144.) What effect will a microburst encounter have upon the aircraft in position 4?. Strong tailwind. Strong updraft. Significant performance increase.

9149. (Refer to Figure 144.) How will the aircraft in position 4 be affected by a microburst encounter?. Performance increasing with a tailwind and updraft. Performance decreasing with a tailwind and downdraft. Performance decreasing with a headwind and downdraft.

9926. (Refer to Figure 144.) On final approach to the airport, airplane in position #5 would experience. decreased ground speed. downdraft. poor performance.

9150. What is the expected duration of an individual microburst?. Two minutes with maximum winds lasting approximately 1 minute. One microburst may continue for as long as 2 to 4 hours. Seldom longer than 15 minutes from the time the burst strikes the ground until dissipation.

9167. What information from the control tower is indicated by the following transmission? “SOUTH BOUNDARY WIND ONE SIX ZERO AT TWO FIVE, WEST BOUNDARY WIND TWO FOUR ZERO AT THREE FIVE.”. A downburst is located at the center of the airport. Wake turbulence exists on the west side of the active runway. There is a possibility of wind shear over or near the airport.

9136. What is the recommended technique to counter the loss of airspeed and resultant lift from wind shear?. Lower the pitch attitude and regain lost airspeed. Avoid overstressing the aircraft, “pitch to airspeed,” and apply maximum power. Maintain, or increase, pitch attitude and accept the lower-than-normal airspeed indications.

9440. Which is an effect of ice, snow, or frost formation on an airplane?. Increased stall speed. Increased pitchdown tendencies. Increased angle of attack for stalls.

9440-1. Frozen dew is. white and opaque. hard and opaque. hard and transparent.

9449. Clear ice generally forms in outside temperature ranges of. -15 to -25ºC. 0 to -10ºC. colder than -25ºC.

9451. Test data indicate that ice, snow, or frost having a thickness and roughness similar to medium or coarse sandpaper on the leading edge and upper surface of a wing can. reduce lift by as much as 40 percent and increase drag by 30 percent. increase drag and reduce lift by as much as 40 percent. reduce lift by as much as 30 percent and increase drag by 40 percent.

9695. The adverse effects of ice, snow, or frost on aircraft performance and flight characteristics include decreased lift and. increased thrust. a decreased stall speed. an increased stall speed.

9302. Even a small amount of frost, ice, or snow may. increase takeoff performance. hinder lift production to a point where takeoff will be impossible. decrease takeoff ground run.

9441. Which is a disadvantage of the one-step over the two-step process when deicing/anti-icing an airplane?. It is more complicated. The holding time is increased. More fluid is used with the one-step method when large deposits of ice and snow must be flushed off airplane surfaces.

9442. The purpose of diluting ethylene glycol deicing fluid with water in non-precipitation conditions is to. raise the eutectic point. decrease the freeze point. increase the minimum freezing point (onset of crystallization).

9443. Which procedure increases holding time when deicing/anti-icing an airplane using a two-step process?. Heated Type 1 fluid followed by cold Type 2 fluid. Cold Type 2 fluid followed by hot Type 2 fluid. Heated Type 1 or 2 fluid followed by cold Type 1 fluid.

9444. Which of the following will decrease the holding time during anti-icing using a two-step process?. Apply heated Type 2 fluid. Decrease the water content. Increase the viscosity of Type 1 fluid.

9753. When icing is detected, particularly while operating an aircraft without deicing equipment, the pilot should. fly to an area with liquid precipitation. fly to a lower altitude. leave the area of precipitation or go to an altitude where the temperature is above freezing.

9756. If icing is suspected on an airplane equipped with deicing equipment, the pilot should. first confirm ice with the ice light prior to deploying the pneumatic boots. operate the pneumatic deicing system several times to clear the ice. operate the pneumatic deicing system once to allow time for the ice removal.

9445. What should the deice/anti-ice fluid temperature be during the last step of a two-phase process?. Hot. Warm. Cold.

9446. What is the minimum glycol content of Type 1 deicing/anti-icing fluid?. 30 percent. 50 percent. 80 percent.

9447. What is the minimum glycol content of Type 2 deicing/anti-icing fluid?. 30 percent. 50 percent. 80 percent.

9448. Anti-icing fluid should provide freezing point protection to. -20°F ambient temperature. +32°F outside temperature or below. a freezing point no greater than 20°F below the ambient or airplane surface temperature.

9450. Freezing Point Depressant (FPD) fluids used for deicing. provide ice protection during flight. are intended to provide ice protection on the ground only. on the ground, cause no performance degradation during takeoff.

9452. Snow on top of deicing or anti-icing fluids. need not be considered as adhering to the aircraft. must be considered as adhering to the aircraft. must be considered as adhering to the aircraft, but a safe takeoff can be made as it will blow off.

9453. Freezing Point Depressant (FPD) fluids are highly soluble in water; however,. ice is slow to absorb it but fast to melt when in contact with FPD. ice absorbs it very fast but is slow to melt when in contact with it. ice is slow to absorb it, and to melt when in contact with it.

9454. Freezing Point Depressant (FPD) fluid residue on engine fan or compressor blades. can increase performance and cause stalls or surges. could cause FPD vapors to enter the aircraft but would have no affect on engine thrust or power. can reduce engine performance and cause surging and/or compressor stalls.

9698. The practice developed and accepted by the North American air carrier industry using traditional North American fluids is to ensure that the freeze point of the remaining film is below ambient temperature by at least. 10°F. 20°F. 20°C.

9700. What is the effect of Freezing Point Depressant (FPD) fluid residue on engine fan or compressor blades?. could cause FPD vapors to enter the aircraft but would have no affect on engine thrust or power. It can increase performance and cause stalls or surges. It can reduce engine performance and cause surging and/or compressor stalls.

9183. What is a feature of supercooled water?. The water drop sublimates to an ice particle upon impact. The unstable water drop freezes upon striking an exposed object. The temperature of the water drop remains at 0°C until it impacts a part of the airframe, then clear ice accumulates.

9221. What condition is necessary for the formation of structural icing in flight?. Supercooled water drops. Water vapor. Visible water.

9224. Which type of icing is associated with the smallest size of water droplet similar to that found in low-level stratus clouds?. Clear ice. Frost ice. Rime ice.

9161. Freezing rain encountered during climb is normally evidence that. a climb can be made to a higher altitude without encountering more than light icing. a layer of warmer air exists above. ice pellets at higher altitudes have changed to rain in the warmer air below.

9223. Which type precipitation is an indication that supercooled water is present?. Wet snow. Freezing rain. Ice pellets.

9180. What condition is indicated when ice pellets are encountered during flight?. Thunderstorms at higher levels. Freezing rain at higher levels. Snow at higher levels.

9774. The most likely condition in which to experience severe inflight icing with the ambient temperature below 0°C is. rain. visible moisture. fog.

9775. Which of the following weather conditions are conducive to inflight icing?. Visible rain with temperatures below 0ºC. Visible rain with temperatures below 10ºC. Visible moisture with temperatures below 5ºC.

9162. What temperature condition is indicated if precipitation in the form of wet snow occurs during flight?. The temperature is above freezing at flight altitude. The temperature is above freezing at higher altitudes. There is an inversion with colder air below.

9179. Which conditions result in the formation of frost?. The temperature of the collecting surface is at or below freezing and small droplets of moisture are falling. Dew collects on the surface and then freezes because the surface temperature is lower than the air temperature. Temperature of the collecting surface is below the dewpoint and the dewpoint is also below freezing.

9748. When flying in the rain and an air temperature of 1°C, a pilot should. not expect icing until the air temperature is 0°C or less. Use autopilot in icing to lower the work load. be aware of the possibility of airframe icing.

9181. When will frost most likely form on aircraft surfaces?. On clear nights with stable air and light winds. On overcast nights with freezing drizzle precipitation. On clear nights with convective action and a small temperature/dewpoint spread.

9736. During an IFR cross-country flight you picked up rime icing which you estimate is 1/2" thick on the leading edge of the wings. You are now below the clouds at 2000 feet AGL and are approaching your destination airport under VFR. Visibility under the clouds is more than 10 miles, winds at the destination airport are 8 knots right down the runway, and the surface temperature is 3 degrees Celsius. You decide to: use a faster than normal approach and landing speed. approach and land at your normal speed since the ice is not thick enough to have any noticeable effect. fly your approach slower than normal to lessen the “wind chill” effect and break up the ice.

8258. The pilot in command of an airplane en route determines that icing conditions can be expected that might adversely affect safety of the flight. Which action is appropriate?. The pilot in command may continue to the original destination airport, after climbing to a higher altitude. The pilot in command shall not continue flight into the icing conditions. The flight may continue to the original destination airport, provided all anti-icing and deicing equipment is operational and is used.

8265. What action is required prior to takeoff if snow is adhering to the wings of an air carrier airplane?. Sweep off as much snow as possible and the residue must be polished smooth. Assure that the snow is removed from the airplane. Add 15 knots to the normal VR speed as the snow will blow off.

9696. A pretakeoff contamination check for snow, ice or frost is required by 14 CFR Part 135. This check is required to. be made within 2 minutes of starting the takeoff roll. be completed within 5 minutes prior to beginning the taxi to the runway. see that the aircraft is clean, therefore, a safe takeoff can be made during the next 5 minutes.

9697. Deicing procedures and equipment developed for large transport airplanes. will not be appropriate for the smaller aircraft, used under 14 CFR Part 135. will be appropriate for all of the smaller aircraft, used under 14 CFR Part 135. may not be appropriate for some of the smaller aircraft, used under 14 CFR Part 135.

9262. What type turbulence should be reported when it causes slight, rapid, and somewhat rhythmic bumpiness without appreciable changes in attitude or altitude, less than one-third of the time?. Occasional light chop. Moderate turbulence. Moderate chop.

9263. What type turbulence should be reported when it causes changes in altitude and/or attitude more than two-thirds of the time, with the aircraft remaining in positive control at all times?. Continuous severe chop. Continuous moderate turbulence. Intermittent moderate turbulence.

9264. What type turbulence should be reported when it momentarily causes slight, erratic changes in altitude and/or attitude, one-third to two-thirds of the time?. Occasional light chop. Moderate chop. Intermittent light turbulence.

9235. Turbulence encountered above 15,000 feet AGL, not associated with cloud formations, should be reported as. convective turbulence. high altitude turbulence. clear air turbulence.

9190. Which type clouds are indicative of very strong turbulence?. Nimbostratus. Standing lenticular. Cirrocumulus.

9226. What is the lowest cloud in the stationary group associated with a mountain wave?. Rotor cloud. Standing lenticular. Low stratus.

9232. Clear air turbulence (CAT) associated with a mountain wave may extend as far as. 1,000 miles or more downstream of the mountain. 5,000 feet above the tropopause. 100 miles or more upwind of the mountain.

9777. Clear air turbulence associated with a jet stream is. most commonly found in temperatures between -40 and -50 degrees C. most commonly found in the vicinity of the tropopause. similar to that associated with a tropical maritime front.

9777-1. The threshold wind speed in the jet stream for clear air turbulence is generally considered to be. 100 kts. 110 kts. 120 kts.

9237. What is a likely location of clear air turbulences?. In an upper trough on the polar side of a jetstream. Near a ridge aloft on the equatorial side of a high pressure flow. Downstream of the equatorial side of a jetstream.

9239. Which type jetstream can be expected to cause the greater turbulence?. A straight jetstream associated with a high pressure ridge. A jetstream associated with a wide isotherm spacing. A curving jetstream associated with a deep low pressure trough.

9230. Which action is recommended if jetstream turbulence is encountered with a direct headwind or tailwind?. Increase airspeed to get out of the area quickly. Change course to fly on the polar side of the jetstream. Change altitude or course to avoid a possible elongated turbulent area.

9231. Which action is recommended regarding an altitude change to get out of jetstream turbulence?. Descend if ambient temperature is falling. Descend if ambient temperature is rising. Maintain altitude if ambient temperature is not changing.

9219. What action is recommended when encountering turbulence due to a wind shift associated with a sharp pressure trough?. Establish a straight course across the storm area. Climb or descend to a smoother level. Increase speed to get out of the trough as soon as possible.

9234. Which arctic flying hazard is caused when a cloud layer of uniform thickness overlies a snow or ice covered surface?. Ice fog. Whiteout. Blowing snow.

9259. Which weather condition is present when the tropical storm is upgraded to a hurricane?. Highest windspeed, 100 knots or more. A clear area or hurricane eye has formed. Sustained winds of 65 knots or more.

9260. What is the general direction of movement of a hurricane located in the Caribbean or Gulf of Mexico region?. Northwesterly curving to northeasterly. Westerly, until encountering land, then easterly. Counterclockwise over open water, then dissipating outward over land.

9266. (Refer to Figure 145.) What was the local Central Standard Time of the Aviation Routine Weather Report at Austin (KAUS)?. 11:53 a.m. 5:53 p.m. 10:53 p.m.

9267. (Refer to Figure 145.) What type of report is listed for Lubbock (KLBB) at 1818Z?. An Aviation selected special weather report. A special report concerning very low station pressure. A Special METAR weather observation, concerning significant weather changes.

9268. (Refer to Figure 146.) What method was used to obtain the METAR at Tyler (KTYR) at 1753Z?. Automated Surface Observing System (ASOS), having a precipitation discriminator. Automatic Meteorological Observing Station (AMOS), with a precipitation discriminator. Automated Weather Observing System (AWOS), without a precipitation discriminator.

9269. (Refer to Figure 145.) What condition is reported at Childress (KCDS)?. Light rain showers. Heavy rain showers began 42 minutes after the hour. The ceiling is solid overcast at an estimated 1,800 feet above sea level.

9270. (Refer to Figure 145.) What condition is reported at Dallas (KDAL)?. The tops of the overcast is 10,000 feet. Temperature/dewpoint spread is 8°F. Altimeter setting is 30.07.

9272. SPECI KGLS 131802Z 10012G21KT 060V140 2SM +SHRA SCT005 BKN035 OVC050CB 24/23 A2980 RMK RAB57 WS TKO RW09L WSHFT 58 FROPA. This SPECI report at Galveston (KGLS) indicates which condition?. Wind steady at 100° magnetic at 12 knots, gusts to 21. Precipitation started at 1757. 5,000 feet overcast with towering cumulus.

273. (Refer to Figure 145.) What weather improvement was reported at Lubbock (KLBB) between 1750 and 1818 UTC?. The wind shift and frontal passage at 1812Z. The vertical visibility improved by 2,000 feet. The temperature and dew point spread improved.

8735. What hazard should you expect for a morning departure from KPDX, based on this METAR? KPDX 271154Z 00000KT 9SM CLR -10/-10 A2979. Wind shear. Frost on the aircraft. Sea breeze.

9274. METAR KMAF 131756Z 02020KT 12SM BKN025 OVC250 27/18 A3009 RMK RAE44. Which weather condition is indicated by this METAR report at Midland (KMAF)?. Rain of unknown intensity ended 16 minutes before the hour. The ceiling was at 25,000 feet MSL. Wind was 020° magnetic at 20 knots.

9275. METAR KSPS 131757Z 09014KT 6SM -RA SCT025 OVC090 24/22 A3005. SPECI KSPS 131820Z 01025KT 3SM +RA FC OVC015 22/21 A3000. Which change took place at Wichita Falls (KSPS) between 1757 and 1820 UTC?. The rain became lighter. Atmospheric pressure increased. A funnel cloud was observed.

9276. (Refer to Figure 146.) What was the ceiling at Walnut Ridge (KARG)?. 1,000 feet AGL. 2,400 feet AGL. 1,000 feet MSL.

9277. METAR KHRO 131753Z 09007KT 7SM FEW020 BKN040 30/27 A3001. SPECI KHRO 131815Z 13017G26KT 3SM +TSRA SCT020 BKN045TCU 29/24 A2983 RMK RAB12 WS TKO LDG RW14R FRQ LTGICCG VC. What change has taken place between 1753 and 1815 UTC at Harrison (KHRO)?. The ceiling lowered and cumulonimbus clouds developed. Thundershowers began at 12 minutes past the hour. Visibility reduced to IFR conditions.

9824. In this METAR excerpt, “SLP993 SNINCR 1/10” means. 0.1" of snow on the runway land zone during the last hour. 1" of snow in the last 10 hours. 1" and a total of 10" of snow is on the ground with 1" in the last hour.

9704. Data that may be added (manual weather augmentation) to the Automated Weather Observing System (AWOS) report is limited to. the precipitation accumulation report, an automated variable visibility, and wind direction remark. thunderstorms (intensity and direction), precipitation (type and intensity), and obstructions to visibility (dependent on the visibility being 3 miles or less). density Altitude, NOTAMs, and reported slant range visibility.

9716. The prevailing visibility in the following METAR is METAR KFSM 131756Z AUTO 00000KT M1/4SM R25/0600V1000FT -RA FG VV004 06/05 A2989 RMK AO2 $. less than 1/4 statute mile. measured 1/4 statute mile. a mean (average) of 1/4 statute mile.

9717. The symbol ($) at the end of the following METAR indicates that METAR KFSM 131756Z AUTO 00000KT M1/4SM R25/0600V1000FT -RA FG VV004 06/05 A2989 RMK AO2 $. the latest information is transmitted over a discrete VHF frequency at KFSM. the latest information is broadcast on the voice portion of a local navaid at KFSM. maintenance is needed on the system.

9718. The VV001 in the following METAR indicates METAR KFSM 131756Z AUTO 00000KT M1/4SM R25/0600V1000FT -RA FG VV001 A2989 RMK AO2 VIS 3/4 RWY19 CHINO RWY19 $. an observer reported the vertical visibility as 100 feet. a 100 foot indefinite ceiling. the variability value is 100 feet.

9242. METAR KFSO 030900Z VRB02KT 7SM MIFG SKC 15/14 A3012 RMK SLP993 6///// T01500139 56012 In the above METAR, the “SLP993 6////” indicates. sea-level pressure 999.3 hectopascals which in the last 6 hours has dropped .4 hectopascals. sea-level pressure 999.3 hectopascals and an indeterminable amount of precipitation has occurred over the last 3 hours. sea-level pressure 999.3 hectopascals and in the last 6 hours that four-tenths of an inch of precipitation has fallen.

9244. Which primary source contains information regarding the expected weather at the destination airport, at the ETA?. Low-Level Prog Chart. Weather Depiction Charts. Terminal Aerodrome Forecast.

9245. Weather conditions expected to occur in the vicinity of the airport, but not at the airport, are denoted by the letters “VC.” When VC appears in a Terminal Aerodrome Forecast, it covers a geographical area of. a 5 to 10 statute mile radius from the airport. a 5-mile radius of the center of a runway complex. 10 miles of the station originating the forecast.

9248. What weather is predicted by the term VCTS in a Terminal Aerodrome Forecast?. Thunderstorms are expected in the vicinity. Thunderstorms may occur over the station and within 50 miles of the station. Thunderstorms are expected between 5 and 25 miles of the runway complex.

9246. Which are the only cloud types forecast in the Terminal Aerodrome Forecast?. Altocumulus. Cumulonimbus. Stratocumulus.

9278. A PROB40 (PROBability) HHhh group in an International Terminal Aerodrome Forecast (TAF) indicates the probability of. thunderstorms or other precipitation. precipitation or low visibility. thunderstorms or high wind.

9707. On the constant pressure analysis chart, satellite and aircraft observations are used in the analysis, over areas of sparse data. A satellite observation plotted using. a station circle at the cloud top location. a square at the cloud top location. a star at the cloud top location.

9709. A calm wind that is forecast, in the International Terminal Aerodrome Forecast (TAF) is encoded as. VRB00KT. 00000KT. 00003KT.

9710. In the International Terminal Aerodrome Forecast (TAF), a variable wind direction is noted by “VRB” where the three digit direction usually appears. A calm wind appears in the TAF as. 00003KT. VRB00KT. 00000KT.

9711. On the constant pressure analysis chart, aircraft and satellite observations are used in the analysis over areas of sparse data. An aircraft observation is plotted using. a station circle at the aircraft location. a square at the aircraft location. a star at the aircraft location.

9281. Constant Pressure Analysis Charts contain contours, isotherms and some contain isotachs. The contours depict. ridges, lows, troughs and highs aloft. highs, lows, troughs, and ridges on the surface. highs, lows, troughs, and ridges corrected to MSL.

9283. Vertical wind shear can be determined by comparing winds on vertically adjacent constant pressure charts. The vertical wind shear that is critical for probability of turbulence is. 4 knots or greater per 1,000 feet. 6 knots or more per 1,000 feet. greater than 8 knots per 1,000 feet.

9287. (Refer to Figure 149.) What approximate wind direction, speed, and temperature (relative to ISA) are expected for a flight over OKC at FL 370?. 265° true; 27 knots; ISA +1°C. 260° true; 27 knots; ISA +6°C. 260° magnetic; 27 knots; ISA +10°C.

9288. (Refer to Figure 149.) What approximate wind direction, speed, and temperature (relative to ISA) are expected for a flight over TUS at FL 270?. 347° magnetic; 5 knots; ISA -10°C. 350° true; 5 knots; ISA +5°C. 010° true; 5 knots; ISA +13°C.

9289. (Refer to Figure 149.) What will be the wind and temperature trend for an SAT ELP TUS flight at 16,000 feet?. Temperature decrease slightly. Windspeed decrease. Wind direction shift from southwest to east.

9290. (Refer to Figure 149.) What will be the wind and temperature trend for an STL MEM MSY flight at FL 330?. Windspeed decrease. Wind shift from west to north. Temperature increase 5°C.

9291. (Refer to Figure 149.) What will be the wind and temperature trend for a DEN ICT OKC flight at 11,000 feet?. Temperature decrease. Windspeed increase slightly. Wind shift from calm to a westerly direction.

9292. (Refer to Figure 149.) What will be the wind and temperature trend for a DSM LIT SHV flight at 12,000 feet?. Windspeed decrease. Temperature decrease. Wind direction shift from northwest to southeast.

9293. (Refer to Figure 149.) What is the forecast temperature at ATL for the 3,000-foot level?. +6°C. +6°F. Not reported.

9294. (Refer to Figure 149.) What approximate wind direction, speed, and temperature (relative to ISA) are expected for a flight over MKC at FL 260?. 260° true; 43 knots; ISA +10°C. 260° true; 45 knots; ISA -10°C. 260° magnetic; 42 knots; ISA +9°C.

9295. What wind direction and speed aloft are forecast by this WINDS AND TEMPERATURE ALOFT FORECAST (FD) for FL390 — “750649”?. 350° at 64 knots. 250° at 106 knots. 150° at 6 knots.

9296. What wind direction and speed aloft are forecast by this WINDS AND TEMPERATURE ALOFT FORECAST (FD) for FL390 — “731960”?. 230° at 119 knots. 131° at 96 knots. 073° at 196 knots.

9251. Forecast winds and temperatures aloft for an international flight may be obtained by consulting. Area Forecasts published by the departure location host country. The current International Weather Depiction Chart appropriate to the route. Wind and Temperature Aloft Charts prepared by the U.S. National Centers of Environmental Prediction (NCEP).

9255. A station is forecasting wind and temperature aloft to be 280° at 205 knots; temperature -51°C at FL390. How would this data be encoded in the FD?. 780051. 789951. 280051.

9939. (Refer to Figure 149A, Area 10.) What is the forecasted wind direction, speed, and temperature over ELY at 30,000 feet?. 330°, 35 knots, 33 °C. 040°, 35 knots, -33 °C. 220°, 35 knots, -33 °C.

9175. Isobars on a surface weather chart represent lines of equal pressure. at the surface. reduced to sea level. at a given atmospheric pressure altitude.

9218. Under what conditions would clear air turbulence (CAT) most likely be encountered?. When constant pressure charts show 20-knot isotachs less than 150 NM apart. When constant pressure charts show 60-knot isotachs less than 20 NM apart. When a sharp trough is moving at a speed less than 20 knots.

9236. A strong wind shear can be expected. on the low pressure side of a 100-knot jetstream core. where the horizontal wind shear is 15 knots, in a distance equal to 2.5° longitude. if the 5°C isotherms are spaced 100 NM or closer together.

9310. (Refer to Figure 154.) What is the height of the 300-millibar level at the low pressure center in Canada?. 9,120 meters MSL. 18,000 meters MSL. 11,850 meters MSL.

9305. What information is provided by a Convective Outlook (AC)?. It describes areas of probable severe icing and severe or extreme turbulence during the next 24 hours. It provides prospects of both general and severe thunderstorm activity during the following 24 hours. It indicates areas of probable convective turbulence and the extent of instability in the upper atmosphere (above 500 mb).

9252. How will an area of thunderstorm activity, that may grow to severe intensity, be indicated on the Severe Weather Outlook Chart?. SLGT within cross-hatched areas. APCHG within any area. SVR within any area.

9578. When are severe weather watch bulletins (WW) issued?. Every 12 hours as required. Every 24 hours as required. Unscheduled and issued as required.

9705. The Hazardous Inflight Weather Advisory Service (HIWAS) is a continuous broadcast over selected VORs of. SIGMETs, CONVECTIVE SIGMETs, AIRMETs, Severe Weather Forecast Alerts (AWW), and Center Weather Advisories (CWA). SIGMETs, CONVECTIVE SIGMETs, AIRMETs, Wind Shear Advisories, and Severe Weather Forecast Alerts (AWW). Wind Shear Advisories, Radar Weather Reports, SIGMETs, CONVECTIVE SIGMETs, AIRMETs, and Center Weather Advisories (CWA).

9256. At what time are current AIRMETs broadcast in their entirety by the Hazardous Inflight Weather Advisory Service (HIWAS)?. 15 and 45 minutes after the hour during the first hour after issuance, and upon receipt. Every 15 minutes until the AIRMET is canceled. There is a continuous broadcast over selected VORs of Inflight Weather Advisories.

9257. If a SIGMET alert is announced, how can information contained in the SIGMET be obtained?. ATC will announce the hazard and advise when information will be provided in the FSS broadcast. By contacting a weather watch station. By contacting the nearest flight service.

9249. If squalls are reported at the destination airport, what wind conditions exist?. Sudden increases in windspeed of at least 15 knots, to a sustained wind speed of 20 knots, lasting for at least 1 minute. A sudden increase in wind speed of at least 16 knots, the speed rising to 22 knots or more for 1 minute or longer. Rapid variation in wind direction of at least 20° and changes in speed of at least 10 knots between peaks and lulls.

9284. (Refer to Figure 148.) Which system in the Convective SIGMET listing has the potential of producing the most severe storm?. The storms in Texas and Oklahoma. The storms in Colorado, Kansas, and Oklahoma. The isolated storm 50 miles northeast of Memphis (MEM).

9285. When you hear a SIGMET on an ATC frequency forecasting severe icing conditions on the route to your destination, you plan for. the installed transport category airplane ice protection system protecting against all types and levels of icing as designed. very little airframe icing because of an OAT of -10°C or colder, the moisture is already frozen and cannot adhere to airplane surfaces. the possibility of freezing rain and freezing drizzle that can accumulate on and beyond the limits of any deicing/anti-icing equipment.

9286. Which type weather conditions are covered in the Convective SIGMET?. Embedded thunderstorms, lines of thunderstorms, and thunderstorms with 3/4-inch hail or tornadoes. Cumulonimbus clouds with tops above the tropopause and thunderstorms with 1/2-inch hail or funnel clouds. Any thunderstorm with a severity level of VIP 2 or more.

9747. The Telephone Information Briefing Service (TIBS) recordings are provided by selected Automated Flight Service Stations and. are updated on the hour. are designed to replace the standard briefing given by a flight service specialist. contain area briefings encompassing a 50 NM radius.

9747-1. All ATC facilities using radar weather processors with the ability to determine precipitation intensities will describe the intensity as. light, moderate, heavy, intense, extreme, or severe. light, moderate, heavy, extreme, severe. light, moderate, heavy, extreme.

9747-2. Maximum turbulence potential charts (GTG-2) are issued. every morning at 0400. two times a day. hourly.

9747-3. Airborne weather radar is installed to help the crew. penetrate weather between storm cells. avoid severe weather. avoid storm turbulence and hail.

9247. What sources reflect the most accurate information on current and forecast icing conditions?. Low-Level Sig Weather Prog Chart, RADATs, and the Area Forecast. PIREPs, Area Forecast, and the Freezing Level Chart. AIRMET Zulus.

9250. Which type of weather can only be directly observed during flight and then reported in a PIREP?. Turbulence and structural icing. Jetstream-type winds and icing. Level of the tropopause and turbulence.

9271. (Refer to Figure 145.) The peak wind at KAMA was reported to be from 320° true at 39 knots,. which occurred at 1743Z. with gusts to 43 knots. with .43 of an inch liquid precipitation since the last report.

9713. KFTW UA/OV DFW/TM 1645/FL100/TP PA30/ SK SCT031-TOP043/BKN060-TOP085/OVC097- TOPUNKN/WX FV00SM RA/TA 07. This pilot report to Fort Worth (KFTW) indicates. the aircraft is in light rain. that the top of the ceiling is 4,300 feet. the ceiling at KDFW is 6,000 feet.

9922. What is indicated by the following report? TYR UUA/OV TYR180015/TM 1757/FL310/TP B737/ TB MOD-SEV CAT 350-390. An urgent pilot report for moderate to severe clear air turbulence. A routine pilot report for overcast conditions from flight levels 350-390. A special METAR issued on the 18th day of the month at 1757Z.