meteorology education for flight school instructors mefsi dr. charles (chip) west meteorologist in...
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Meteorology Education for Flight Meteorology Education for Flight School InstructorsSchool Instructors
MEFSIMEFSI
Dr. Charles (Chip) West Dr. Charles (Chip) West
Meteorologist in ChargeMeteorologist in ChargeAtlanta Center Weather Service UnitAtlanta Center Weather Service Unit
WEATHER-RELATED ACCIDENTS
0 50 100 150 200 250 300
NTSB Accident Data for 1995
Obscurations
Thunderstorms
Icing
High Density Altitude
Turbulence
Low Ceilings
Reduced Visibilities
Adverse Winds
Fatal Accidents Non-Fatal Accidents
WEATHER CAUSES/ FACTORS (1142 ACCIDENTS)
UNFAVORABLE WINDS
LOW CEILING
HIGH DENSITYALTITUDE
FOG
UP/DOWN DRAFTS
RAIN
THUNDERSTORMS
INDUCTION ICING
SNOW
TURBULENCE
ICING
OBST’D TO VISION
OTHER
CONT’D VFR INTOADVERSE WEATHER
0 100 200 300 400 500
FATAL NON-FATAL
FB-5-8-6
SURFACE
INFLIGHT
(AIR-TO-AIR)
SLANT RANGE
(AIR-TO-GROUND)
PILOT VISIBILITIES
CLOUDS RESTRICT FLIGHT VISIBILITIES TO ZEROCLOUDS RESTRICT FLIGHT VISIBILITIES TO ZERO
INFLIGHT
(AIR-TO-AIR)SLANT RANGE
(AIR-TO-GROUND)
SEA LEVEL
MOUNTAIN OBSCURATIONS
REPORTED CEILING 500 FEET
GOOD SLANT RANGE VISIBILITY
EFFECTIVE PILOT CEILING 500 FEET
POOR SLANT RANGE VISIBILITY
VERTICAL VISIBILITY 500 FEET
EFFECTIVE PILOT CEILING LESS THAN 500 FEET
FOG: A cloud on the ground.
CLOUD
1. SURFACE TEMPERATURE DECREASES TO DEW POINT BY:
- CONTACT WITH A COLDER SURFACE.
- UPSLOPE FLOW (ADIABATIC COOLING).
- EVAPORATIONAL COOLING (LATENT HEAT).
AND/OR
2. SURFACE DEW POINT INCREASES TO
TEMPERATURE BY EVAPORATION:
- AIR OVER MOIST SURFACE.
- WARM RAIN FALLING THROUGH COLDER AIR.
CAUSES OF FOG
FR
EQ
UE
NC
Y
SUNSET SUNSETSUNRISE
NIGHT DAY
PEAK FREQUENCY
DAILY FOG FREQUENCY
FB-5-8-17
1
7
8
6
5
4
3
2
JAN APRFEB MAYMAR JUN JUL AUG SEP OCT NOV DEC
ANNUAL FOG FREQUENCYD
AY
S
20 KNOTS
CLOUD LAYER
TURBULENT MIXING
WINDS IN EXCESS OF 15 KNOTS WILL OFTEN PRODUCE LOW CEILINGS.
CEILING
LOW CEILINGS
BROKEN TO OVERCAST LOW CLOUDS
FAVORABLE CONDITIONS: LIGHT WINDS, CLEAR SKIES,
SHALLOW SURFACE-BASED MOIST LAYER
RADIATION FOG
RADIATIONAL COOLING OF GROUND AT NIGHT
FOG
WARM WATER
ADVECTION FOG
FOG
FAVORABLE CONDITIONS
MOIST AIR MOVING (BEING ADVECTED) OVER A COLDER SURFACE
WINDS 5-15 KNOTS
TEMPERATURE COOLED TO DEW POINT COLD LAND
FAVORABLE CONDITIONS
- COLD AIR MOVING OVER WARM WATER
- LIGHT TO MODERATE WINDS
WARM WATER
STEAM FOG
FB-5-8-34
FB-5-8-37 COURTESY OF DR. JOE MORAN
H
ADVECTION FOG
WARMWATER
COLDWATER
FOG
L
L
H
ADVECTION FOG
FOG
WIND
UPSLOPE FOG
FAVORABLE CONDITIONS
MOIST STABLE AIR MOVING UPSLOPE
WINDS 5 - 15 KNOTS
FOG
WARM AIR COLD AIR
FAVORABLE CONDITIONS
- WARM RAIN FALLING THROUGH COLDER AIR
RAIN-INDUCED FOG
H
HAZE AND SMOKE
FAVORABLE CONDITIONS
LARGE SURFACE HIGH
STABLE AIR
PARTICLE CONCENTRATIONS AND STABILITY
TEMPERATURE
HE
IGH
T
HAZE
FAVORABLE CONDITIONS- STRONG TURBULENT WIND
- BARREN TERRAIN
LUBBOCK
DALLAS
BLOWING DUST/DUST
DUST CAN BE CARRIED MANY MILES FROM ITS SOURCE
40KTS
20KTS
UNSTABLE
15,000 FT
FAVORABLE CONDITIONS
- STRONG SURFACE WINDS
- DRY CONDITIONS
- LOOSE, SANDY SOIL
BLOWING SAND
WIND
VOLCANIC ASHVOLCANIC ASH
ICINGICING
ICING INTENSITIES
TRACE - PERCEPTIBLE, NO SIGNIFICANTACCUMULATION
LIGHT - SIGNIFICANT ACCUMULATION FOR A PROLONGED FLIGHT (OVER 1 HOUR)
MODERATE - SIGNIFICANT ACCUMULATION FOR SHORTER PERIODS OF FLIGHT
SEVERE - RAPID, DANGEROUS ACCUMULATIONS
CLEAR ICING
FAVORABLE CONDITIONS
LARGE DROPLETS IN CUMULIFORM CLOUDS OR FREEZING RAIN
TEMPERATURES 0°C TO -10°C
FAVORABLE CONDITIONS
SMALL SUPERCOOLED DROPLETS IN STRATIFORM CLOUDS
TEMPERATURES 0°C TO -10°C
RIME ICING
FAVORABLE CONDITIONS
LARGE AND SMALL DROPLETS COEXIST
LIQUID AND FROZEN PARTICLES COEXIST
WET SNOW
MIXED ICING
FREEZING TEMPERATURES
DECREASESLIFTINCREASES
DRAG
DECREASESTHRUST
INCREASESWEIGHT
HAZARDOUS EFFECTS TO FLIGHTHAZARDOUS EFFECTS TO FLIGHT
ICING INTENSITY EFFECTS(WITHOUT DEICERS/WITH DEICERS)
TRACE - NO HAZARDS/ NO DEICERS REQUIRED
LIGHT - HAZARDOUS IF CONTINUED/ OCCASIONAL USE OF DEICERS REQUIRED
MODERATE - HAZARDOUS, REQUIRES DIVERSION/CONTINUOUS USE OF DEICERS REQUIRED
SEVERE -IMMEDIATE HAZARD/ UNCONTROLLED BY DEICERS
GROUND LEVEL
SEA LEVEL
1000
2000
3000
4000
5000
6000
7000
8000
9000
-10°C 0°C
MOST PROBABLE ICING LAYER
ICING LAYER
SINGLE FREEZING LEVEL
0°C
STRATUS CLOUDS
ICING ZONE
0°C 0°C
FAST ACCUMULATION
CUMULUS CLOUDS
OR LESS
OR LESS
TEMP 0°C OR LOWER
RAIN, DRIZZLE, OR WET SNOW
PRECIPITATION
WARM FRONTWARM AIR
MOIST AND STABLEABOVE FREEZING TEMPERATURES
STRATIFIED CLOUDS
FRONTS
COLD AIR
0°C
BELOW FREEZING TEMPERATURES
SUPERCOOLED RAIN FREEZES ON IMPACT
(FREEZING RAIN) {
WARM RAIN
PL RA
TURBULENCETURBULENCE
WIND SHEARS
VERTICALSPEED SHEAR
HORIZONTALDIRECTIONAL SHEAR
HORIZONTALSPEED SHEAR
SHEARS OF HORIZONTAL WINDS
SHEAR OF VERTICAL WINDS
INTENSITY OF TURBULENCE VARIES WITH
AIRCRAFT TYPE
UA/OV ABQ/TM 1640/FL100/TP B737/TB LGT DURD 100-SFC
UA/OV ABQ/TM 1645/FL070/TP PA31/TB MOD
WARM AIR
INVERSION
COLD AIRTEM
PER
ATU
RE
TEMPERATURE INVERSIONTEMPERATURE INVERSION
CALM WIND
WARM AIR
INVERSION
COLD CALM AIRTEM
PER
ATU
RE
TEMPERATURE INVERSIONTEMPERATURE INVERSION
RADIATIONAL COOLINGRADIATIONAL COOLING
WARM AIR 25 KNOTS
COLD CALM AIR
TEMPERATURE INVERSIONTEMPERATURE INVERSION
COLD AIR TRAPPED IN VALLEYCOLD AIR TRAPPED IN VALLEY
JET STREAMSJET STREAMS
SOUTH
ISOTACHS
TROPOPAUSE
NORTH
JETJETCORECORE
70 KTS
90 KTS
110 KTS
130 KTS
VERTICAL CROSS SECTION
MOIST AIR
SMOOTH FLIGHTABOVE CLOUDS
CUMULIFORMCLOUDS
CONVECTIVE TURBULENCECONVECTIVE TURBULENCE
MOIST CONVECTIONMOIST CONVECTION
SUNNY SKIES UNEVEN SURFACE HEATING
CLEARWARM
10,000 ft.
3,000 ft.
DRY AIR
SMOOTH FLIGHTABOVE CONVECTION
CONVECTIVE TURBULENCECONVECTIVE TURBULENCE
DRY CONVECTIONDRY CONVECTION
MECHANICAL TURBULENCEMECHANICAL TURBULENCE
STRONG SURFACE WINDSSTRONG SURFACE WINDS
20 Knots
FRICTION CAUSES TURBULENT MIXING
MECHANICAL TURBULENCEMECHANICAL TURBULENCE
OBSTRUCTIONS IN THE AIR FLOWOBSTRUCTIONS IN THE AIR FLOW
WIND
FAVORABLE CONDITIONS
•STRONG LOW LEVEL WIND 20 KNOTS OR GREATER
•GROUND LEVEL OBSTRUCTIONS
MECHANICAL TURBULENCEMECHANICAL TURBULENCE
HILLS / MOUNTAINSHILLS / MOUNTAINS
LEEWARDLEEWARDWINDWARDWINDWARD
WINDWIND
FAVORABLE CONDITIONS
MODERATE OR STRONGER WIND ACROSS THE HILL / MOUNTAIN
MECHANICAL TURBULENCEMECHANICAL TURBULENCE
MOUNTAIN WAVEMOUNTAIN WAVEFAVORABLE CONDITIONS
-WINDS 25 KTS OR GREATER ACROSS-WINDS INCREASING WITH HEIGHT-STABLE ATMOSPHERE
STRATOSPHERE
TROPOPAUSE
TROPOSPHERE
WAVE LENGTH5 TO 30 MILES
LENTICULAR CLOUD
ROTOR
TURBULENCE
CAP CLOUD
WIND
70
60
50
40
30
20
10
0
100
0’s
OF
FE
ET
MOUNTAIN WAVE CLOUDSMOUNTAIN WAVE CLOUDS
CCSL
ACSL
ROTOR
WARM
COLD
FRONTSFRONTSWIND SHEAR TURBULENCEWIND SHEAR TURBULENCE
COLD FRONT
CONVECTIVE TURBULENCE
COLD MOIST UNSTABLE
WARM MOIST UNSTABLE
FRONTS
MECHANICAL TURBULENCE
STRONG GUSTY SURFACE WINDS
MOIST WARM
UNSTABLE
COLD STABLE
SC
TCU
NS
CB
ST BR
WARM AND STATIONARY FRONTS
CONVECTIVE TURBULENCE
HAZARDOUS EFFECTS
INTENSITY AIRCRAFT REACTION INSIDE AIRCRAFT
LIGHT MOMENTARILY CAUSES SLIGHTERRATIC CHANGES IN ALTITUDEAND/OR ATTITUDE.
UNSECURED OBJECTS MAYBE DISPLACED SLIGHTLY.FOOD SERVICE EASILYCONDUCTED. NODIFFICULTY IN WALKING.
MODERATE CHANGES IN ALTITUDE AND/ORATTITUDE. AIRCRAFT REMAINSIN POSITIVE CONTROL.VARIATIONS IN INDICATEDAIRSPEED.
UNSECURED OBJECTS MAYBE DISLODGED. FOODSERVICE AND WALKING ISDIFFICULT.
SEVERE LARGE, ABRUPT CHANGES INALTITUDE AND/OR ATTITUDE.LARGE VARIATIONS ININDICATED AIRSPEED.AIRCRAFT MAY BEMOMENTARILY OUT OFCONTROL.
FOOD SERVICE ANDWALKING IMPOSSIBLE.
EXTREME AIRCRAFT VIOLENTLY TOSSEDABOUT AND IS PRACTICALLYIMPOSSIBLE TO CONTROL. MAYCAUSE STRUCTURAL DAMAGE.
STRONG DESIRE TO LAND.
DOWNSLOPE FLOW
WIND
WINDWARD
LEEWARD
FAVORABLE CONDITIONS
WINDS MODERATE OR GREATER ACROSS MOUNTAINS
17
CROSS WIND
Pressure Altitude andPressure Altitude andthe loss of FL180-200the loss of FL180-200
LOW-LEVEL WIND SHEAR
CALM AIR
TEM
PE
RA
TUR
E
INVERSIONLAYER
RESPONSE ITEM
WHAT EFFECT DOES A HEADWIND HAVE ON AN EN ROUTE AIRCRAFT?
A. INCREASES FUEL CONSUMPTION
B. CAUSES TURBULENCE
C. INCREASES TRUE AIRSPEED
A. INCREASES FUEL CONSUMPTION
B. CAUSES TURBULENCE
C. INCREASES TRUE AIRSPEED
RESPONSE ITEM
THE TYPES OF PILOT VISIBILITY NECESSARY TO
MAINTAIN PROPER AIRCRAFT ORIENTATION
ARE
A. INFLIGHT AND SLANT RANGE.
B. INFLIGHT AND SURFACE.
C. SLANT RANGE AND SURFACE.
A. INFLIGHT AND SLANT RANGE.
B. INFLIGHT AND SURFACE.
C. SLANT RANGE AND SURFACE.
RESPONSE ITEM
THE HAZARDOUS CONDITION THAT CAUSES
INDEFINITE CEILINGS IS
A. LOW OVERCAST CLOUDS.
B. MOUNTAIN OBSCURATIONS.
C. RESTRICTIONS TO VISIBILITY.
A. LOW OVERCAST CLOUDS.
B. MOUNTAIN OBSCURATIONS.
C. RESTRICTIONS TO VISIBILITY.
RESPONSE ITEM
THE FLIGHT CONDITION WITH THE HIGHEST
FATALITY RATE IS
A. CONTINUED VFR INTO ADVERSE WEATHER.
B. THUNDERSTORMS.
C. ADVERSE WINDS.
A. CONTINUED VFR INTO ADVERSE WEATHER.
B. THUNDERSTORMS.
C. ADVERSE WINDS.
RESPONSE ITEM
AT WHAT TIME ARE REDUCED VISIBILITIES DUE
TO FOG THE LOWEST?
A. AROUND NOON
B. SHORTLY AFTER SUNSET
C. SHORTLY AFTER SUNRISE
F-5-7-45
A. AROUND NOON
B. SHORTLY AFTER SUNSET
C. SHORTLY AFTER SUNRISE
RESPONSE ITEM
UNDER WHICH CONDITION IS FOG MOST LIKELY
TO FORM?
A. TEMPERATURE INCREASES MORE
RAPIDLY THAN THE DEW POINT
B. TEMPERATURE DECREASES AND THE DEW
POINT INCREASES
C. DEW POINT DECREASING MORE RAPIDLY
THAN
TEMPERATUREFF-8-14-14
A. TEMPERATURE INCREASES MORE
RAPIDLY THAN THE DEW POINT
B. TEMPERATURE DECREASES AND THE DEW
POINT INCREASES
C. DEW POINT DECREASING MORE RAPIDLY
THAN
TEMPERATURE
RESPONSE ITEM
FOG WHICH FORMS AS A RESULT OF NIGHTTIME
COOLING OF THE GROUND IS
A. STEAM FOG.
B. UPSLOPE FOG.
C. RADIATION FOG.
FB-5-8-44
A. STEAM FOG.
B. UPSLOPE FOG.
C. RADIATION FOG.
RESPONSE ITEM
ADVECTION FOG CAN FORM WHEN MOIST AIR
A. FLOWS OVER A COLDER SURFACE.
B. FLOWS OVER A WARMER SURFACE.
C. IS COLDER THAN SURFACE.
F-5-7-40
A. FLOWS OVER A COLDER SURFACE.
B. FLOWS OVER A WARMER SURFACE.
C. IS COLDER THAN SURFACE.
RESPONSE ITEM
FOG WHICH FORMS AS A RESULT OF COLD AIR
MOVING OVER WARM WATER IS
A. ADVECTION FOG.
B. STEAM FOG.
C. RADIATION FOG.
FB-5-8-41
A. ADVECTION FOG.
B. STEAM FOG.
C. RADIATION FOG.
RESPONSE ITEM
A LARGE SURFACE HIGH AND STABLE AIR ARE
FAVORABLE FOR
A. HAZE AND SMOKE.
B. PRECIPITATION.
C. BLOWING DUST.
A. HAZE AND SMOKE.
B. PRECIPITATION.
C. BLOWING DUST.
RESPONSE ITEM
WHICH TYPE OF RESTRICTION WOULD BE MOST
PROBABLE ABOVE 2,000 FEET AGL?
A. BLOWING SNOW
B. BLOWING SAND
C. DUST
A. BLOWING SNOW
B. BLOWING SAND
C. DUST
RESPONSE ITEM
WHICH TYPE OF PRECIPITATION MOST
EFFECTIVELY RESTRICTS VISIBILITY?
A. RAIN
B. SNOW
C. DRIZZLE
A. RAIN
B. SNOW
C. DRIZZLE
RESPONSE ITEM
THE TEMPERATURE RANGE WHERE STRUCTURAL
ICING IS MOST LIKELY IS
A. 0°C TO -10°C.
B. 5°C TO -18°C.
C. -10°C TO -18°C.
THE TEMPERATURE RANGE WHERE STRUCTURAL
ICING IS MOST LIKELY IS
A. 0°C TO -10°C.
B. 5°C TO -18°C.
C. -10°C TO -18°C.
RESPONSE ITEM
THE MOST FAVORABLE LOCATION FOR
STRUCTURAL ICING IN THE VICINITY OF
MOUNTAINS IS ON THE __________ SIDE.
A. LEEWARD
B. WINDWARD
C. DOWNSLOPE
THE MOST FAVORABLE LOCATION FOR
STRUCTURAL ICING IN THE VICINITY OF
MOUNTAINS IS ON THE __________ SIDE.
A. LEEWARD
B. WINDWARD
C. DOWNSLOPE
RESPONSE ITEM
TURBULENCE IS A RESULT OF FLIGHT INTO
A. HEADWINDS.
B. LIGHT WINDS AND STABLE AIR.
C. SMALL SCALE EDDIES.
TURBULENCE IS A RESULT OF FLIGHT INTO
A. HEADWINDS.
B. LIGHT WINDS AND STABLE AIR.
C. SMALL SCALE EDDIES.
RESPONSE ITEM
THE PRIMARY CAUSE OF TURBULENCE IS
A. RAIN.
B. WIND SHEAR.
C. STRATUS CLOUDS.
THE PRIMARY CAUSE OF TURBULENCE IS
A. RAIN.
B. WIND SHEAR.
C. STRATUS CLOUDS.
RESPONSE ITEM
“CAT” REFERS TO TURBULENCE ASSOCIATED WITH
A. CONVECTION.
B. MECHANICAL TURBULENCE.
C. THE JET STREAM.
“CAT” REFERS TO TURBULENCE ASSOCIATED WITH
A. CONVECTION.
B. MECHANICAL TURBULENCE.
C. THE JET STREAM.
RESPONSE ITEM
THE TYPE OF TURBULENCE THAT RESULTS FROM THE INTERRUPTION OF SMOOTH FLOW BY OBJECTS IS
A. WIND SHEAR ZONES.
B. CONVECTION.
C. MECHANICAL.
THE TYPE OF TURBULENCE THAT RESULTS FROM THE INTERRUPTION OF SMOOTH FLOW BY OBJECTS IS
A. WIND SHEAR ZONES.
B. CONVECTION.
C. MECHANICAL.
RESPONSE ITEM
AT WHAT TIME OF THE DAY WOULD YOU MOST
LIKELY EXPECT WIND SHEAR TURBULENCE
DUE TO A SURFACE BASED INVERSION?
A. 0700 LOCAL
B. 1400 LOCAL
C. 2000 LOCAL
A. 0700 LOCAL
B. 1400 LOCAL
C. 2000 LOCAL
RESPONSE ITEM
THE ALTITUDES WHICH CONTAIN TURBULENCE
ASSOCIATED WITH THE JET STREAM ARE
GENERALLY __________ FEET.
A. BELOW 10,000
B. 10,000 TO 20,000
C. ABOVE 24,000
A. BELOW 10,000
B. 10,000 TO 20,000
C. ABOVE 24,000
RESPONSE ITEM
THE EFFECTS OF MOUNTAIN WAVES OFTEN
EXTEND FROM THE SURFACE TO
A. LESS THAN 5,000 FEET.
B. THE ALTITUDE OF THE MOUNTAIN
CREST.
C. SLIGHTLY ABOVE THE
TROPOPAUSE.
A. LESS THAN 5,000 FEET.
B. THE ALTITUDE OF THE MOUNTAIN
CREST.
C. SLIGHTLY ABOVE THE
TROPOPAUSE.
RESPONSE ITEM
THE MOST INTENSE TURBULENCE WITH A
MOUNTAIN WAVE IS TYPICALLY ASSOCIATED
WITH THE _________ CLOUD.
A. ROTOR
B. ACSL
C. CCSL
A. ROTOR
B. ACSL
C. CCSL
RESPONSE ITEM
SHOWERS ARE AN INDICATOR OF ___________
TURBULENCE.
A. SHEAR ZONE
B. CONVECTIVE
C. MECHANICAL
A. SHEAR ZONE
B. CONVECTIVE
C. MECHANICAL
RESPONSE ITEM
WHAT INTENSITY OF ICING IDENTIFIES
SIGNIFICANT ACCUMULATIONS AFTER
RELATIVELY SHORT PERIODS OF FLIGHT?
A. LIGHT
B. MODERATE
C. SEVERE
A. LIGHT
B. MODERATE
C. SEVERE
RESPONSE ITEM
SOLID, SMOOTH ICE FORMED EITHER FROM
SUPERCOOLED WATER DROPS OR FROM
FREEZING RAIN IS CALLED ________ ICE.
A. CLEAR
B. RIME
C. MIXED
A. CLEAR
B. RIME
C. MIXED
RESPONSE ITEM
THE TYPE OF ICING USUALLY
ASSOCIATED WITH STRATIFORM CLOUDS
IS
A. CLEAR.
B. RIME.
C. MIXED.
A. CLEAR.
B. RIME.
C. MIXED.
RESPONSE ITEM
THE ICING INTENSITY THAT REQUIRES CONTINUOUS USE OF DEICERS IS
A. LIGHT.
B. MODERATE.
C. SEVERE.
THE ICING INTENSITY THAT REQUIRES CONTINUOUS USE OF DEICERS IS
A. LIGHT.
B. MODERATE.
C. SEVERE.
RESPONSE ITEM
DURING CLIMBOUT INTO THE CUMULIFORM CLOUD, ATWHAT ALTITUDE WOULD YOU EXPECT INITIAL ICING?
A. 3,000 FEET B. 5,000 FEET C. 7,000 FEET
DURING CLIMBOUT INTO THE CUMULIFORM CLOUD, ATWHAT ALTITUDE WOULD YOU EXPECT INITIAL ICING?
A. 3,000 FEET B. 5,000 FEET C. 7,000 FEET
0oC
RESPONSE ITEM
THE INTENSITY OF TURBULENCE THAT
CAUSES LARGE VARIATIONS IN INDICATED
AIRSPEED AND MOMENTARY LOSS OF
CONTROL OF THE AIRCRAFT IS
A. MODERATE.
B. SEVERE.
C. EXTREME.
A. MODERATE.
B. SEVERE.
C. EXTREME.
RESPONSE ITEM
IN ORDER TO AVOID AN ACCIDENT BY RAPIDLY DESCENDING INTO THE MOUNTAIN THE PILOT SHOULD:
A. CLIMB 5,000 FEET OR MORE ABOVE CREST.
B. DECREASE SPEED AT CREST HEIGHT.
C. FLY AT CREST HEIGHT BUT STAY OUT OF DOWNDRAFT.
A. CLIMB 5,000 FEET OR MORE ABOVE CREST.
B. DECREASE SPEED AT CREST HEIGHT.
C. FLY AT CREST HEIGHT BUT STAY OUT OF DOWNDRAFT.