FCTM non Normal Operations

Question 1

Troubleshooting

Answer 1

Troubleshooting can be defined as:

• taking steps beyond a published NNC in an effort to improve or correct a non-normal condition
• initiating an annunciated checklist without a light, alert, or other indication to improve or correct a perceived non-normal condition
• initiating diagnostic actions.

Troubleshooting beyond checklist directed actions is rarely helpful and has caused further loss of system function or failure. In some cases, accidents and incidents have resulted.

Crew distraction, caused by preoccupation with troubleshooting, has been a key factor in several fuel starvation and CFIT accidents. Boeing recommends completion of the NNC as published whenever possible, in particular for flight control malfunctions that are addressed by a NNC.

Question 2

Approach and Landing

Answer 2

When a non-normal situation occurs, a rushed approach can often complicate the situation. Unless circumstances require an immediate landing, complete all corrective actions before beginning the final approach.

Note: The use of autobrakes is recommended because maximum autobraking may be more effective than maximum manual braking due to timely application upon touchdown and symmetrical braking. However, the Advisory Information in the PI chapter of the QRH includes Non-Normal Configuration Landing Distance data specific to the use of maximum manual braking. When used properly, maximum manual braking provides the shortest stopping distance.

Question 3

Plan to land at the nearest suitable airport

Answer 3

A suitable airport is defined by the operating authority for the operator based on guidance material but, in general, must have adequate facilities and meet certain minimum weather and field conditions.

If required to divert to the nearest suitable airport, the guidance material typically specifies that the pilot should select the nearest suitable airport “in point of time” or “in terms of time.” In selecting the nearest suitable airport, the pilot-in-command should consider the suitability of nearby airports in terms of facilities and weather and their proximity to the airplane position.

The pilot-in-command may determine, based on the nature of the situation and an examination of the relevant factors, that the safest course of action is to divert to a more distant airport than the nearest airport. For example, there is not necessarily a requirement to spiral down to the airport nearest the airplane’s present position if, in the judgment of the pilot-in-command, it would require equal or less time to continue to another nearby airport.

For persistent smoke or a fire which cannot positively be confirmed to be completely extinguished, the safest course of action typically requires the earliest possible descent, landing and evacuation. This may dictate landing at the nearest airport appropriate for the airplane type, rather than at the nearest suitable airport normally used for the route segment where the incident occurs.

Question 4

Engine Oil System Indications Engine

Answer 4

Oil System Indications Oil pressure is considered as the most significant of several oil system indicators.
Oil temperature, oil quantity and oil pressure indications enable the flight crew to recognize a deteriorating oil system. While engine operation is governed by both oil pressure and oil temperature limits, there is no minimum oil quantity limit.
Therefore, there is no low oil quantity NNC in the QRH.

If abnormal oil quantity indications are observed, check oil pressure and oil temperature. If oil pressure and oil temperature indications are normal, operate the engine normally. Accomplish the appropriate NNC for any non-normal oil pressure or oil temperature indications.

Question 5

Engine Failure versus Engine Fire After Takeoff

Answer 5

The NNC for an engine failure is normally accomplished after the flaps have been retracted and conditions permit.
In case of an engine fire, when the airplane is under control, the gear has been retracted, and a safe altitude has been attained (minimum 400 feet AGL) accomplish the NNC memory items.

Question 6

Engine Tailpipe Fire

Answer 6

Engine tailpipe fires can occur due to the following:

• engine control malfunction
• excess fuel in the combustor, turbine or exhaust nozzle
• oil accumulation in the hot section flow path or exhaust system.

If a tailpipe fire is reported, the crew should accomplish the NNC without delay. Flight crews should consider the following when dealing with this situation:

• motoring the engine is the primary means of extinguishing the fire
• to prevent an inappropriate evacuation, flight attendants should be notified without significant delay
• communications with ramp personnel and the tower are important to determine the status of the tailpipe fire and to request fire extinguishing assistance
• the engine fire checklist is inappropriate because the engine fire extinguishing agent is not effective against a fire inside the tailpipe.

Question 7

Loss of Engine Thrust Control

Answer 7

Loss of Engine Thrust Control All turbo fan engines are susceptible to this malfunction whether engine control is hydro-mechanical, hydro-mechanical with supervisory electronics (e.g. PMC) or Full Authority Digital Engine Control (FADEC). Engine response to a loss of control varies from engine to engine. Malfunctions have occurred in-flight and on the ground.
The major challenge the flight crew faces when responding to this malfunction is recognizing the condition and determining which engine has malfunctioned.

The Engine Limit or Surge or Stall NNC is written to include this malfunction.This condition can occur during any phase of flight.

Question 8

Loss of Thrust on Both Engines

Answer 8

Dual engine failure is a situation that demands prompt action regardless of altitude or airspeed. Accomplish memory items and establish the appropriate airspeed to immediately attempt a windmill restart.
There is a higher probability that a windmill start will succeed if the restart attempt is made as soon as possible (or immediately after recognizing an engine failure) to take advantage of high engine RPM.

Initiate the memory portion of the LOSS OF THRUST ON BOTH ENGINES NNC before attempting an APU start for the reasons identified above.
If the windmill restart is not successful, an APU start should be initiated as soon as practical to provide electrical power and starter assist during follow-on engine start attempts.

During in-flight restart attempts use the lower of the EGT redline and the EGT start limit redline, if displayed. A hung or stalled in-flight start is normally indicated by stagnant RPM and increasing EGT. During start, engines may accelerate to idle slowly but action should not be taken if RPM is increasing and EGT is not near or rapidly approaching the limit.

Question 9

Airframe Vibration Due to Engine Severe Damage or Separation

Answer 9

Certain engine failures, such as fan blade separation can cause high levels of airframe vibration. Although the airframe vibration may seem severe to the flight crew, it is extremely unlikely that the vibration will damage the airplane structure or critical systems. However, the vibration should be reduced as soon as possible by reducing airspeed and descending.

In general, as airspeed decreases vibration levels decrease. As airspeed or altitude change the airplane can transition through various levels of vibration. It should be noted that the vibration may not completely stop.

Once airframe vibration has been reduced to acceptable levels, the crew must evaluate the situation and determine a new course of action based on weather, fuel remaining, and available airports.

Question 10

Recommended Technique for an In-Flight Engine Shutdown

Answer 10

Any time an engine shutdown is needed in flight, good crew coordination is essential. Airplane incidents have turned into airplane accidents as a result of the flight crew shutting down the incorrect engine.
When the flight path is under complete control, the crew should proceed with a deliberate, systematic process that identifies the affected engine and ensures that the operating engine is not shut down. Do not rush through the shutdown checklist, even for a fire indication.

The following technique is an example that could be used:
When an engine shutdown is needed, the PF disconnects the A/T. The PF then verbally coordinates confirmation of the affected engine with the PM and then slowly retards the thrust lever of the engine that will be shutdown.
Coordinate activation of the start lever as follows:

• PM places a hand on and verbally identifies the start lever for the engine that will be shutdown
• PF verbally confirms that the PM has identified the correct start lever
• PM moves the start lever to cutoff.

If the NNC requires activation of the engine fire switch, coordinate as follows:

• PM places a hand on and verbally identifies the engine fire switch for the engine that is shutdown
• PF verbally confirms that the PM has identified the correct engine fire switch
• PM pulls the engine fire switch.

Question 11

Discharging Fire Bottles during an Evacuation

Answer 11

The evacuation NNC specifies discharge of the engine or APU fire bottles if an engine or APU fire warning light is illuminated. However, evacuation situations can present possibilities regarding the potential for fire that are beyond the scope of the NNC and may not activate an engine or APU fire warning.
The crew should consider the following when deciding whether to discharge one or more fire bottles into the engines and/or APU:

• if an engine fire warning light is not illuminated, but a fire indication exists or a fire is reported in or near an engine, discharge both available fire bottles into the affected engine
• if the APU fire warning light is not illuminated, but a fire indication exists or a fire is reported in or near the APU, discharge the APU bottle
• the discharged halon agent is designed to extinguish a fire and has very little or no fire prevention capability in the engine nacelles. Halon dissipates quickly into the atmosphere
• there is no reason to discharge the engine or APU fire bottles for evacuations not involving fire indications existing or reported in or near an engine or APU, e.g., cargo fire, security or bomb threat, etc.

Question 12

Flight Controls Leading Edge or Trailing Edge Device Malfunctions

Leading Edge Flaps Transit - Landing

Answer 12

If an asymmetrical or skewed leading edge device condition occurs, use the LEADING EDGE FLAPS TRANSIT NNC to determine the flap setting and VREF for approach. VREF provides 15° bank angle maneuver capability and allows for 15° overshoot protection in all cases.

Do not hold the airplane off during landing flare. Floating just above the runway surface to deplete the additional threshold speed wastes available runway and increases the possibility of a tail strike.

Note: If the gear is retracted during a go-around and flap position is greater than 25, a landing gear configuration warning occurs.

Question 13

Flight Controls Leading Edge or Trailing Edge Device Malfunctions

Trailing Edge Flap Asymmetry - Landing

Answer 13

If a trailing edge flap asymmetry occurs, full maneuver capability exists even if the asymmetry occurred at flaps just out of the full up position.
Burn off fuel to reduce landing weight and lower approach speed. Fly accurate airspeeds in the landing pattern.
At lesser flap settings, excess airspeed is difficult to dissipate, especially when descending on final approach. Pitch attitude and rate of descent on final is higher than for a normal landing.

During flare, airspeed does not bleed off as rapidly as normal.
Fly the airplane onto the runway at the recommended touchdown point. Flare only enough to achieve an acceptable reduction in the rate of descent. Do not allow the airplane to float. Floating just above the runway surface to deplete additional speed wastes available runway and increases the possibility of a tail strike.

Do not risk touchdown beyond the normal touchdown zone in an effort to achieve a smooth landing.

Note: If the gear is retracted during a go-around and flap position is greater than 25, a landing gear configuration warning occurs.

Question 14

Runaway Stabilizer

Answer 14

A runaway stabilizer condition can be recognized by continuous uncommanded movement of stabilizer trim, or if stabilizer trim is occurring in a manner that is not appropriate for current flight conditions. During manual flight or flight with the autopilot engaged, automatic stabilizer trim can be commanded by the Speed Trim System or autopilot trim. Since commanded stabilizer trim can occur automatically, the pilot needs to consider the existing flight conditions to determine if a runaway stabilizer condition exists. For example, some stabilizer trim movement can be expected to occur during speed, altitude, or configuration changes.

During a runaway stabilizer condition the crew should maintain airplane pitch control through the use of the control column, main electric stabilizer trim, and thrust levers. The control column must be held firmly before the autopilot (if engaged) is disengaged to maintain airplane pitch control and retain any elevator commands from the autopilot. After the autopilot and autothrottle are disengaged, use the control column and thrust levers to establish appropriate pitch attitude and airspeed. If uncommanded trim motion continues, it may stop when the control column is displaced in the opposite direction and the control column cutout is activated.

Use main electric stabilizer trim to reverse any stabilizer trim movement and to reduce control column forces. Sustained use of main electric stabilizer trim may be needed. It is important to note that even though the steps in the Runaway Stabilizer checklist are sequential, these steps can be accomplished simultaneously.

If uncommanded stabilizer trim movement continues, place both STAB TRIM cutout switches to the CUTOUT position. Manual stabilizer trim should then be used for the remainder of the flight.

Question 15

Standby Rudder On

Answer 15

The STANDBY RUDDER ON light illuminates any time the standby rudder PCU is operating.
If this light illuminates independent of crew action or a hydraulic system malfunction, either of two conditions may have occurred.
The most probable cause is a force fight monitor malfunction inadvertently activating the standby pump and powering the standby PCU.
In this case, three PCU control valves power the rudder and full rudder inputs should be avoided to prevent applying excessive loads on the rudder. The NNC is written for this condition. The second cause may be because of a pressure difference between the two main PCU control valves indicating a jammed condition. This condition does not require a NNC because satisfactory rudder operation is available using the standby rudder PCU.

Question 16

Unreliable Airspeed

Answer 16

Unreliable airspeed indications can result due to erroneous data from the pitot/static system, AOA vanes, ADIRU, or damage to the radome.

Increased reliance on automation has
de-emphasized the practice of setting known pitch attitudes and thrust settings. However, if an unreliable airspeed condition occurs, the flight crew should be familiar with the approximate pitch attitude and thrust setting for each phase of flight.

This familiarity can be gained by noting the pitch attitude and thrust setting occasionally during normal flight. Any significant change in pitch attitude from the attitude normally required to maintain a particular airspeed or Mach number should alert the flight crew to a potential airspeed problem.
If abnormal airspeed indications are recognized, immediately set the target pitch attitude and thrust setting for the airplane configuration from the Airspeed Unreliable memory items. Once flight path is under control and the airplane is not in a critical phase of flight, accomplish the Airspeed Unreliable NNC. The crew should alert ATC if unable to maintain assigned altitude or if altitude indications are unreliable.

Question 17

Fuel Balance

Answer 17

The primary purpose of fuel balance limitations on Boeing airplanes is for the structural life of the airframe and landing gear and not for controllability. A reduction in structural life of the airframe or landing gear can be caused by frequently operating with out-of-limit fuel balance conditions.
Lateral control is not significantly affected when operating with fuel beyond normal balance limits.

The primary purpose for fuel balance alerts is to inform the crew that imbalances beyond the current state may result in increased trim drag and higher fuel consumption. The IMBAL NNC should be accomplished when the fuel balance alert is received.

There is a common misconception among flight crews that the fuel crossfeed valve should be opened immediately after an in-flight engine shutdown to prevent fuel imbalance. This practice is contrary to Boeing recommended procedures and could aggravate a fuel imbalance. This practice is especially significant if an engine failure occurs and a fuel leak is present.
Arbitrarily opening the crossfeed valve and starting fuel balancing procedures, without following the checklist, can result in pumping usable fuel overboard.

Question 18

Fuel Balancing Considerations

Answer 18

The crew should consider the following when performing fuel balancing procedures:

• use of the Fuel Balancing Supplementary Procedure in conjunction with good crew coordination reduces the possibility of crew errors
• routine fuel balancing when not near the imbalance limit increases the possibility of crew errors and does not significantly improve fuel consumption
• during critical phases of flight, fuel balancing should be delayed until workload permits. This reduces the possibility of crew errors and allows crew attention to be focused on flight path control
• fuel imbalances that occur during approach need not be addressed if the reason for the imbalance is obvious (e.g. engine failure or thrust asymmetry, etc.).

Question 19

Fuel Leak

Answer 19

Any time an unexpected fuel quantity indication, FMC fuel message, or imbalance condition is experienced, a fuel leak should be considered as a possible cause.
Maintaining a fuel log and comparing actual fuel burn to the flight plan fuel burn can help the pilot recognize a fuel leak.

Significant fuel leaks, although fairly rare, are difficult to detect. The Engine Fuel Leak NNC assumes the leak is between the front spar and the engine.

This is the most common type of fuel leak since fuel lines are exposed in the strut. Most other fuel lines, such as a crossfeed manifold, are contained within the tanks. A significant fuel leak directly from a tank to the outside is very rare due to the substantial wing structure that forms the tanks.

There is no specific fuel leak annunciation on the flight deck. A fuel leak must be detected by changes or discrepancies in expected fuel consumption, or by some annunciation that occurs because of a fuel leak. Any unexpected and sustained change in fuel quantity or fuel balance should alert the crew to the possibility of a fuel leak.

Question 20

Fuel leak suspected

Answer 20

Some reasons are:

• The total fuel remaining is less than the planned fuel remaining. The total fuel can be less than planned fuel for a number of reasons, such as a fuel leak, unforecast headwinds, fuel sloshing (such as from high angles of pitch). Sloshing fuel would be a temporary effect. Flight crews should consider these when deciding whether or not to suspect a fuel leak.
• An engine has excessive fuel flow. A faulty fuel flow meter or an engine fuel leak downstream of the fuel flow meter will cause an excessive fuel flow indication. Total fuel remaining compared to planned fuel remaining should be considered when deciding whether or not to suspect a fuel leak.
• One main tank is abnormally low compared to the other main tanks and the expected fuel remaining in the tanks. One tank indicating abnormally low can be caused by a fuel leak, engine out or a crossfeed problem. With an engine out, if the totalizer and calculated values are tracking as expected, a fuel leak would not be suspected. A fuel pump with higher pressure and a faulty crossfeed valve can cause one tank to provide fuel to more than one engine, causing one tank to indicate low. In this case, the fact that total fuel should still match planned fuel, a fuel leak would not be suspected. If a fuel leak is suspected, it is imperative to follow the NNC.

Question 21

Hydraulic System(s) Inoperative - Landing

Answer 21

If the landing gear is extended using manual gear extension, the gear cannot be raised. Trailing edge flaps can be extended or retracted using the alternate (electric) system.
However, the rate of flap travel is significantly reduced. Leading edge devices can also be extended using the alternate system, but they cannot be retracted.

If system B is lost, or both system A and B are lost, the applicable NNC recommends the use of flaps 15 to improve go-around capabilities. With flaps 15, the airplane may tend to float during the flare. Do not allow the airplane to float. Fly the airplane onto the runway at the recommended point.

Question 22

Manual Reversion

Answer 22

Fly a long straight-in approach. Keep thrust changes small and slow to allow for pitch trim changes.

Landing configuration and approach airspeed should be established on the runway centerline so that only a slight reduction in thrust is required to achieve the landing profile. Do not make a flat approach.
Anticipate that the airplane tends to pitch down as thrust is reduced for touchdown. To help reduce the pitch down tendency, trim slightly nose up on approach and initiate the flare at a higher than normal altitude. Although trimming during the flare is not normally recommended, the high control column forces required during landing in this situation can be reduced by adding a small amount of nose up trim during the flare.

After touchdown, thrust reverser operation is slow. Apply steady brake pressure since only accumulator pressure is available. Do not apply excessive forward pressure to the control column. Excessive forward pressure without the speedbrakes deployed can result in less weight on the main gear and reduced braking capability.

Do not attempt to taxi the airplane after stopping because the accumulator pressure may be depleted or close to being depleted.

If a go-around is required, apply thrust smoothly and in coordination with stabilizer trim. Rapid thrust application results in nose-up pitch forces.

Question 23

Landing Gear Lever Jammed in the Up Position

Answer 23

The landing gear could be jammed in the UP position due to a mechanical jam of the landing gear handle, or if the landing gear selector valve is stuck in the up position. Either condition results in the landing gear remaining pressurized in the UP position.

The LANDING GEAR LEVER JAMMED IN THE UP POSITION NNC has the crew attempt to bypass the solenoid linkage by pulling the landing gear override trigger.
If the landing gear cannot be extended due to a mechanical jam of the landing gear handle, this may resolve the jam.
If this action does not result in the landing gear lever moving to the DN position and all landing gear indicating down and locked, the landing gear is most likely jammed in the UP position because the landing gear selector valve is stuck in the up position. In this case the crew must pull the manual gear extension handles to release the uplocks and allow the gears to extend.

Due to system redesign in the 737NG, there is no requirement to depressurize either hydraulic system as was required in earlier 737s.

Question 24

Tire Failure During or After Takeoff

Answer 24

When a tire failure is suspected during takeoff, the landing gear can be retracted normally.
Wheel well design features and automatic wheel braking prevent damage from a failed tire.

If the landing gear lever cannot move to UP, do the Gear Lever Will Not Move Up NNC as soon as practical.
If the crew suspects a tire failure during takeoff, the Air Traffic Service facility serving the departing airport should be advised of the potential for tire pieces remaining on the runway. The crew should consider continuing to the destination unless there is an indication that other damage has occurred (non-normal engine indications, engine vibrations, hydraulic system failures or leaks, etc.).

Continuing to the destination will allow the airplane weight to be reduced normally, and provide the crew an opportunity to plan and coordinate their arrival and landing when the workload is low.

Considerations in selecting a landing airport include, but are not limited to:

• sufficient runway length and acceptable surface conditions to account for the possible loss of braking effectiveness
• sufficient runway width to account for possible directional control difficulties
• altitude and temperature conditions that could result in high ground speeds on touchdown and adverse taxi conditions
• runway selection options regarding “taxi-in” distance after landing
• availability of operator maintenance personnel to meet the airplane after landing to inspect the wheels, tires, and brakes before continued taxi
• availability of support facilities should the airplane need repair.

Question 25

Landing on a Flat Tire

Answer 25

Boeing airplanes are designed so that the landing gear and remaining tire(s) have adequate strength to accommodate a flat nose gear tire or main gear tire.
When the pilot is aware of a flat tire prior to landing, use normal approach and flare techniques, avoid landing overweight and use the center of the runway. Use differential braking as needed for directional control.

With a single tire failure, towing is not necessary unless unusual vibration is noticed or other failures have occurred. In the case of a flat nose wheel tire, slowly and gently lower the nose wheels to the runway while braking lightly. Runway length permitting, use idle reverse thrust. Autobrakes may be used at the lower settings. Once the nose gear is down, vibration levels may be affected by increasing or decreasing control column back pressure. Maintain nose gear contact with the runway. Flat main gear tire(s) cause a general loss of braking effectiveness and a yawing moment toward the flat tire with light or no braking and a yawing moment away from the flat tire if the brakes are applied harder. Maximum use of reverse thrust is recommended. Do not use autobrakes. If uncertain whether a nose tire or a main tire has failed, slowly and gently lower the nose wheels to the runway and do not use autobrakes. Differential braking may be required to steer the airplane. Use idle or higher reverse thrust as needed to stop the airplane.

Question 26

Overspeed

Answer 26

VMO/MMO is the airplane maximum certified operating speed and should not be exceeded intentionally. However, crews can occasionally experience an inadvertent overspeed. Airplanes have been flight tested beyond VMO/MMO to ensure smooth pilot inputs will return the airplane safely to the normal flight envelope.

At high altitude, wind speed or direction changes may lead to overspeed events. Although autothrottle logic provides for more aggressive control of speed as the airplane approaches VMO or MMO, there are some conditions that are beyond the capability of the autothrottle system to prevent short term overspeeds.
When correcting an overspeed during cruise at high altitude, avoid reducing thrust to idle which results in slow engine acceleration back to cruise thrust and may result in over-controlling the airspeed or a loss of altitude.
If autothrottle corrections are not satisfactory, leave the autopilot engaged, deploy partial speedbrakes slowly until a noticeable reduction in airspeed is achieved. When the airspeed is below VMO/MMO, retract the speedbrakes at the same rate as they were deployed. The thrust levers can be expected to advance slowly to achieve cruise airspeed; if not, they should be pushed up more rapidly.

During climb or descent, if VNAV or LVL CHG pitch control is not correcting the overspeed satisfactorily, switching to the V/S mode temporarily may be helpful in controlling speed. In the V/S mode, the selected vertical speed can be adjusted slightly to increase the pitch attitude to help correct the overspeed. As soon as the speed is below VMO/MMO, VNAV or LVL CHG may be re-selected.