Cold WX Operations Flashcards
Cold Wx operation considerations are concerned with?
low temps, ice, snow, slush, standing water on airplane, ramps, taxiways, RW’s.
Explain Icing conditions
OAT on ground, or TAT in flights is 10deg or below and:
*visible moisture (clouds, fog with viz less than 1600m, rain, snow, sleet, ice crystals, present or
*ice, snow , slush, standing water on ramps, taxiways, runways.
Name the MAIN procedures which are part of the Cold WX OPS Suppl proc
Exterior inspection
Preflight FO
Engine Start
EAI operation ground
WAI ground
Before Taxi
De/Anti Icing
Before Take Off
Takeoff
EAI in flight
Fan ice removal
WAI in flight
COLD TEMP Correction
App and landing
After Landing
Shutdown
Secure
Do normal exterior inspection, with additional steps?
Surfaces
*light coatings of frost up to 3mm lower wing due cold fuel is OK, as long as LED, control surface, tab surface, upper wind surface, winglet surface, control balance panel cavities must be free of snow, ice, frost. Thin HOAR frost upper surface OK, if all vents and ports clear.This hoarfrost is a uniform white deposit of fine crystalline texture, on exposed surfaces on cold and cloudless night. Thin enough to distinguish surface features underneath.
Control surface balance panel cavities
check drainage after snow removal, puddles water may freeze inflight.
pitot probes and ports
all free of snow, ice.Water rundown after snow removal may free immediately forward of static ports and cause ice buildup which disturbs airflow over static ports.
Air conditioning inlet and exits
air inlets, exists, outflow valve, free snow and ice.APU operating, verify outflow valve fully open.
Engine inlets
inlet cowling free snow, ice
fab free to rotate
Snow, ice on fan spinner or fan blade during extended shutdown periods, must be removed by maintenance or other means before engine start.
Snow/Ice on fan spinner/fan blades during approach or taxi in is OK, if fan free to rotate and snow/ice removed using ice shedding proc during taxi out and before setting TO thrust.
Fuel tank vents
landing gear doors
APU air inlets.
free of snow, ice before APU start.
Preflight proc FO?
Probe Heat switches ON
Engine cold soaked for 1 or + hours temps below -40deg?
dont start or motor engine.Maintenance heating of Hydro Mechanical Unit.
Engine cold soaked for 3 or + hours temps below -40deg?
dont start or motor engine.Maintenance procedures for adverse weather starter servicing.
Temps below -35deg?
idle for 2min, before changing thrust lever position.
Oil pressure scenario?
several min for OIL PRESSURE to reach normal operating pressure. Oil P may go above normal range, and OIL FILTER BYPASS may illuminate. Operate engine IDLE until oil press normal range. OIL press remains above normal, after OIL TEMP is stable, shut down engine.
Display Units during engine start cold wx?
additional WU time before displayed engine indictions accurately show changing values. May appear less bright than normal.
Engine ani ice after start?
selected on after both engines started. Remain ON during all ground ops if icing conditions exist or anticipated.
Use which criteria to use EAI?
Temp and visible moisture. DOnt use airframe visual cues. Late activation allow excessive ingestion of ice result damage of failure.
Light indication using EAI?
COWL VALVE OPEN light bright, then DIM. COWL ANTI ICE light stays extinguished.
COWL VALVE OPEN light stays BRIGHT with engines IDLE?
*APU BLEED OFF
*ISOLATION VALVE AUTO
*Area behind clear
*Thrust increase Max 30% N1
WAI, when to use and not to use?
After engine start and TO with icing conditions, unless AC protected by Type 11 or IV fluid.
WAI use, which lights ON?
L/R VALVE OPEN light Bright, then dim.
VALVE OPEN lights cycle bright/dim?
Due to control valves cycling closed/open in response to thrust setting and duct temp.
IDG and COLD OIL?
IDG normally stabilize 1min, can take 5min to produce steady power due cold oil.
Flight control check @ low temps?
increase in control forces
Setting flaps, if they STOP?
Flap lever should be placed immediately in same position as indicated.