Weather Flashcards
What season will the jet stream be stronger?
The jet stream is stronger and more south in the winter.
What is the difference between surface charts and constant pressure charts relative to the lines shown?
The lines on a surface analysis chart are isobars (lines of constant pressure). The lines on an upper air analysis show contour lines which connect areas of equal height above mean sea level since all the chart shows the same pressure.
Does the wind parallel contour lines on a constant pressure chart?
Yes
What affects does ice have on an airplane?
It increases drag, decreases lift, and lowers the critical angle of attack
Where is ice most commonly oriented relative to a low pressure system?
North East Quadrant of a low pressure system
If you are riding in turbulence in a cloud below the freezing level, what can you expect?
An increase of turbulence is indicative of an increase in lift, which would result in us expecting an increase in ice accumulation.
What are conditions where clear ice will most likely be found?
- temps close to the freezing point with large amounts of water
- high aircraft velocities
- large droplets
What conditions where rime ice will most likely be found?
- low temperatures
- less liquid water
- low velocities
Approved anti-icing and de-icing equipment is not approved for flight into freezing rain. T/F
True
The older a cloud it, the more or less likely it is to contain ice?
less likely, because most supercooled water droplet will form into ice crystals
T/F The more lifting action, the greater liklihood of ice?
True
Describe Ram Rise Temperature increase?
The surface temperature of he aircraft increases with airspeed
What is roll upset with regards to icing?
It occurs when ice builds up aft of the protected surfaces, which can create aileron self-deflection due to negative pressure above the wing, which degrade roll handling characteristics.
How to recover from roll upset?
- lower angle of attack
- increase airspeed or extend first notch of flaps to further lower angle of attack
- level the wings if in a turn
Where is turbulence the greatest in a thunderstorm?
Usually the front side of the storm as well as the side it is being fed moisture
A storm that is moving eat, with a moist southerly flow will have most turbulence on the east and southside of the storm?
True
A thunderstorm gust front can extend how far out in front ofa strong storm?
over 15 miles in front of it
Airmass thunderstorms are caused mainly by what?
Air flowing over mountains or unequal heating of the earth
Embedded thunderstorms are most likely where?
Along the warm front or stationary frontal zones
When are convective sigmets issued?
- lines of thudnerstorms at least 60 miles long
- Area of very strong thunderstorms affecting 3,000 square miles covering at least 40% of the area
- Embedded or severe t-storms
- tornadoes
- 3/4” of greater hail at surface
- wind gusts greater than 50 knots at the surface
- indication of rapidly changing conditions
Where is the v-notch in a thunderstorm, and what does it represent?
It indicates that large particles are being swept away from the updraft by strong winds. Usually points in the direction the storm is moving
What kind of weather information can be available in a cockpit?
airborne weather radar, lightning detection systems, or uplink/downlink weather (nexrad)
What is the latency of most nexrad XM up link radar imagery?
around 5 minuts
What weather conditions are the primary reason for weather to be below ILS minimums?
Fog
