-
3381. Every physical process of weather is accompanied by, or is the result of, a
heat exchange
-
3382. What causes variations in altimeter settings between weather reporting points?
Unequal heating of the Earth's surface.
-
3448. The development of thermals depends upon
solar heating.
-
3395. The wind at 5,000 feet AGL is southwesterly while the surface wind is southerly. This difference in direction is primarily due to
friction between the wind and the surface.
-
3450. Convective circulation patterns associated with sea breezes are caused by
cool, dense air moving inland from over the water.
-
3383. A temperature inversion would most likely result in which weather condition?
An increase in temperature as altitude is increased.
-
3384. The most frequent type of ground or surface-based temperature inversion is that which is produced by
terrestrial radiation on a clear, relatively still night.
-
3397. What is meant by the term "dewpoint''
The temperature to which air must be cooled to become saturated.
-
3398. The amount of water vapor which air can hold depends on the
air temperature.
-
3399. Clouds, fog, or dew will always form when
water vapor condenses.
-
3400. What are the processes by which moisture is added to unsaturated air?
Evaporation and sublimation.
-
3444. If the temperature/dewpoint spread is small and decreasing, and the temperature is 62 °F, what type weather is most likely to develop?
Fog or low clouds.
-
3421. The boundary between two different air masses is referred to as a
front.
-
3422. One of the most easily recognized discontinuities across a front is
a change in temperature.
-
3423. One weather phenomenon which will always occur when flying across a front is a change in the
wind direction.
-
3385. Which weather conditions should be expected beneath a low-level temperature inversion layer when the relative humidity is high?
Smooth air, poor visibility, fog, haze, or low clouds.
-
3403. What measurement can be used to determine the stability of the atmosphere?
Actual lapse rate.
-
3404. What would decrease the stability of an air mass?
Warming from below.
-
3405. What is a characteristic of stable air?
Stratiform clouds.
-
3408. What feature is associated with a temperature inversion?
A stable layer of air.
-
3412. What are characteristics of a moist, unstable air mass?
Cumuliform clouds and showery precipitation.
-
3413. What are characteristics of unstable air?
Turbulence and good surface visibility.
-
3414. A stable air mass is most likely to have which characteristic?
Poor surface visibility.
-
3406. Moist, stable air flowing upslope can be expected to
produce stratus type clouds.
-
3407. If an unstable air mass is forced upward, what type clouds can be expected?
Clouds with considerable vertical development and associated turbulence.
-
3424. Steady precipitation preceding a front is an indication of
stratiform clouds with little or no turbulence.
-
3433. The conditions necessary for the formation of cumulonimbus clouds are a lifting action and
unstable, moist air.
-
3409. What is the approximate base of the cumulus clouds if the surface air temperature at 1,000 feet MSL is 70 °F and the dewpoint is 48 °F?
6,000 feet MSL.
-
3410. At approximately what altitude above the surface would the pilot expect the base of cumuliform clouds if the surface air temperature is 82 °F and the dewpoint is 38 °F?
10,000 feet AGL.
-
3415. The suffix "nimbus", used in naming clouds, means
a rain cloud.
-
3416. Clouds are divided into four families according to their
height range.
-
3419. What clouds have the greatest turbulence?
Cumulonimbus.
-
3417. An almond or lens-shaped cloud which appears stationary, but which may contain winds of 50 knots or more, is referred to as
a lenticular cloud.
-
3418. Crests of standing mountain waves may be marked by stationary, lens-shaped clouds known as
standing lenticular clouds.
-
3420. What cloud types would indicate convective turbulence?
Towering cumulus clouds.
-
3425. Possible mountain wave turbulence could be anticipated when winds of 40 knots or greater blow
across a mountain ridge, and the air is stable.
-
3442. Upon encountering severe turbulence, which flight condition should the pilot attempt to maintain?
Level flight attitude.
-
3434. What feature is normally associated with the cumulus stage of a thunderstorm?
Continuous updraft.
-
3435. Which weather phenomenon signals the beginning of the mature stage of a thunderstorm?
Precipitation beginning to fall.
-
3436. What conditions are necessary for the formation of thunderstorms?
High humidity, lifting force, and unstable conditions.
-
3437. During the life cycle of a thunderstorm, which stage is characterized predominately by downdrafts?
Dissipating.
-
3438. Thunderstorms reach their greatest intensity during the
mature stage.
-
3939. Thunderstorms which generally produce the most intense hazard to aircraft are
squall line thunderstorms.
-
3440. A nonfrontal, narrow band of active thunderstorms that often develop ahead of a cold front is a known as a
squall line.
-
3441. If there is thunderstorm activity in the vicinity of an airport at which you plan to land, which hazardous atmospheric phenomenon might be expected on the landing approach?
Wind-shear turbulence.
-
3452. Which weather phenomenon is always associated with a thunderstorm?
Lightning.
-
3426. Where does wind shear occur?
At all altitudes, in all directions.
-
3427. When may hazardous wind shear be expected?
In areas of low-level temperature inversion, frontal zones, and clear air turbulence.
-
3428. A pilot can expect a wind-shear zone in a temperature inversion whenever the windspeed at 2,000 to 4,000 feet above the surface is at least
25 knots.
-
3402. The presence of ice pellets at the surface is evidence that there
is a temperature inversion with freezing rain at a higher altitude.
-
3429. One in-flight condition necessary for structural icing to form is
visible moisture.
-
3430. In which environment is aircraft structural ice most likely to have the highest accumulation rate?
Freezing rain.
-
3956. During an IFR cross-country flight, you pick up rime icing 1/2 inch thick on leading edge of the wing. Visibility is more than 10 miles, winds are 8 knots, temp is 3 C. You decide to:
use a faster than normal approach and landing speed.
-
3443. What situation is most conducive to the formation of radiation fog?
Warm, moist air over low, flatland areas on clear, calm nights.
-
3445. In which situation is advection fog most likely to form?
An air mass moving inland from the coast in winter.
-
3446. What types of fog depend upon wind in order to exist?
Advection fog and upslope fog.
-
3447. Low-level turbulence can occur and icing can become hazardous in which type of fog?
Steam fog.
-
3401. Which conditions result in the formation of frost?
The temperature of the collecting surface is at or below the dewpoint of the adjacent air and the dewpoint is below freezing.
-
3432. How does frost affect the lifting surfaces of an airplane on takeoff?
Frost may prevent the airplane from becoming airborne at normal takeoff speed.
-
3206. How will frost on the wings of an airplane affect takeoff performance?
Frost will disrupt the smooth flow of air over the wing, adversely affecting its lifting capability.
-
3431. Why is frost considered hazardous to flight?
Frost spoils the smooth flow of air over the wings, thereby decreasing lifting capability.
|
|