(1)
The area where you will park the airplane must be clear of ice and snow. Chapter 10 gives the full procedures to park the airplane. Use the procedure in Chapter 10 if more steps are necessary because of the weather conditions and length of time the airplane will be parked.
S 583-016
(2)
When it is possible, point the airplane into the direction the wind is usually from.
(a)
Put the wing flaps to the full up position. This will lock the outboard Ailerons in their faired neutral position.
(b)
Use the STABILIZER TRIM switches to put the stabilizer to electrical limit for airplane nose down.
S 493-017
CAUTION: EXAMINE THE ENGINE INTAKE AREAS IMMEDIATELY AFTER SHUT DOWN FOR
_______ ICE THAT IS THERE. REMOVE THE ICE WHILE THE TEMPERATURE OF THE ENGINE DECREASES AND BEFORE YOU INSTALL THE ENGINE PROTECTIVE PLUGS AND COVERS. IF YOU INSTALL THE PLUGS BEFORE THE TEMPERATURE OF THE ENGINE DECREASES, THE REMAINING HEAT IN THE ENGINE WILL MELT THE ICE TO WATER. THIS WATER WILL FLOW TO THE BOTTOM OF THE FAN SECTION. IT WILL FREEZE AGAIN WHEN THE TEMPERATURE OF THE ENGINE IS BELOW FREEZING. THIS WILL LOCK THE TIPS OF THE FAN LOWER BLADES IN ICE.
(3) Install all the plugs and covers, where available, for the intake or exhaust ducts and the different probes such as the pitot tubes. Use a brush to apply a thin layer of anti-ice fluid to the airplane surface before you install the cover. The covers will not freeze to the airplane if you do this.
J. Engine Operation
S 863-018
(1)
The full procedures to operate the engines in cold weather
conditions are in AMM 71-00-00.
S 663-019
(2)
Large pieces of ice and/or snow that go into the engine inlet can cause damage to the internal engine parts. Remove all the ice or snow from the engine inlet ducts before you start the engines.
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747-400
MAINTENANCE MANUAL
S 663-020
(3) Engine icing can occur when the conditions that follow occur.
(a)
There is moisture you can see such as clouds, fog, rain, snow, sleet or ice crystals.
(b)
You will do ground operations with the static air temperature below 50°F.
(c)
You must use the thermal anti-icing system for the engine/nacelle when these conditions occur.
S 843-021
(4) Before you start the engines, make sure there are no fluids around the exhaust areas that can start ignition.
K. Fuel Icing
S 683-022
CAUTION: IF YOU CAN DRAIN THE FUEL FROM THE DRAIN VALVE AFTER YOU
_______ APPLIED HOT AIR TO THE EXTERIOR FOR 3 TO 5 MINUTES DO NOT THINK THAT ALL THE ICE IS MELTED. THE ICE ADJACENT TO THE UNIT YOU ARE NOT SURE ABOUT CAN MELT AND LET SOME WATER AND FUEL FLOW FROM THE DRAIN. BUT, A PIECE OF ICE CAN STAY BEHIND. IF THE FUEL DOES NOT FLOW FROM THE DRAIN VALVE, CONTINUE TO APPLY HOT AIR FOR A SHORT TIME, AND FREQUENTLY DO A CHECK OF THE FLOW FROM THE DRAIN VALVE. CATCH THE FUEL IN A CONTAINER AND MAKE SURE ALL OF THE WATER IS REMOVED.
THE HEAT APPLIED TO THE SUMP DRAIN VALVES FOR THE OUTBOARD MAIN AND RESERVE TANKS WILL NOT REMOVE THE ICE WHICH HAS COLLECTED IN THE TANK SUMP OR IN THE DRAIN LINE BETWEEN THE TANK SUMP AND VALVE. TO REMOVE THIS ICE, YOU MUST PUT THE AIPRLANE IN A WARM HANGAR FOR SUFFICIENT TIME TO MELT THE ICE. THEN DRAIN THE SUMPS UNTIL THE WATER IS REMOVED.
(1)
In cold weather it is necessary to drain the fuel tank sumps prior to refueling to remove water from the fuel tanks if the airplane has been idle for more than 45 minutes prior to refueling. Drain the fuel tank sumps again after refueling if the airplane has been idle for 2 hours or more after refueling, prior to departure (AMM 12-11-03/301). In cold weather water can freeze and, and not let the drain valves open.
S 613-029
(2)
The items that follow have the most effect on the quantity of water in aviation fuels.
