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Boeing 737 Memory Items, Limitations, Systems and Preflight Set UP

Updated: Apr 24

Limitations and QRC information for the Boeing 737-800. These limitations may vary depending on the aircraft and operator you fly for. Please seek/learn your actual aircraft type FCOM, this information is for reference and general information only. Comment below if you have any various limitations and information on the 737 you fly.


Preflight Flows for a B737:

Boeing 737 limitations:

Runway slope: +/- 2°

Maximum take-off and landing tailwind component: 10kts

Maximum speeds for flap: placard

Maximum operating altitude: 41,000ft

Crosswind and wind limitations for B737

Maximum wing component for Autoland:

Headwind: 25kts


Crosswind: 2025kts

Crosswind CAT II/III 15kts

Maximum take-off and landing tailwind component: 15kts

Maximum Crosswind Take-off: 43kts and 25 WET

Maximum Crosswind Landing: 40kts WET/DRY

Severe turbulence penetration speed is 280KIAS/.76M whichever is lower. Applicable to CLB and DES only. During Cruise refer to SP (Supplement procedures) .16

The maximum allowable in-flight difference between Captain and First officer altitude displays for RVSM operations is 200ft.

Weight Limitations:

MRW: 174,700 lbs /

MTOW:174,200 lbs / 79 242KG

MLW: 146,300 lbs / 66,360kG

MZFW:138,300 lbs/

Engine Limitations for the B737:

Maximum and Minimum limits are red

Caution limits are amber

The maximum time limit for take-off thrust is 5 mins

Ignition Limitations for the B737

Engine ignition must be on AUTO/CONT position for:




Operation in heavy rain

APU Limitations:

APU Bleed and Electrical load Inflight 10,000ft

APU bleed 17,000ft

APU electrical load 41,000ft

Boeing 737 Fuel System:

The Boeing 737 has 3 fuel tanks, these tanks are the mains tanks located in the wing and the center tank which is only used if the main tanks one and two are full. The main tanks (wings) contain 8,630 lbs of fuel and the center tank can store 28,803 lbs of fuel. The aircraft can not have an imbalance of more than 1000lbs or 430kgs in the tanks during taxi, take-off, and landing. An imbalance of zero between tanks is scheduled however; imbalances inflight can occur due to engine failure or leak. Each tank can be used to provide fuel to the engines however fuel transfer can not take place in flight.

Fuel Pumps in the B737:

The Boeing 737 has 2 pumps in each tank, the center tanks are a higher pressure so they can supply the engines with fuel prior to the wing tanks. The fuel pumps are powered by the AC system. A total loss of AC power can result in a flame out however the engine-driven pumps (2 in each engine) help provide the required pressure prior to the engine if there is a loss of AC power.

APU fuel pump and fuel feed:

The APU also has an AC pump and DC pump that can allow it to take fuel from the main left tank or center tank if the AC pump is on. Boeing recommends using the Center tank if fuel is in it or the main wing tank to allow the APU DC pump to not wear out.

Boeing Hydraulics System:

The Boeing 737 has 3 hydraulic systems, A,B and the Stand-by system. All 3 have various aircraft components that they power. The system has redundancy through the flight controls being powered by both A and B. The hydraulic system also includes a Power Transfer Unit (PTU) and Landing Gear Transfer Unit). These hydraulic components help with powering the leading edge flaps and retracting the gear when there is a loss of either system A or B.


Flight spoilers Flight Spoilers

Landing Gear Landing Gear Transfer Unit

Ailerons Ailerons

Ground Spoilers Thrust Reverser 2

Rudder Trailing Edge Flaps 2

Alternate Brakes Elevator and Elevator feel

Nose wheel steering Rudder

Thrust Reverser 1 Yaw Damper

Main Cargo Door Normal Brakes

Auto-pilot A Auto-pilot B

PTU Leading Edge Flaps and Slats

Elevator and Elevator Feel Auto-slats

B737 Memory Items, B737 QRH, B737 Emergency, B737 Checklist, Boeing 737 memory items, Boeing 737 Checklist

Memory Items:

Unreliable Airspeed,

Runaway Stabilizer,,

Cabin Altitude Warning

Emergency Descent,

Engine Fire, Severe Damage or Separation,

Engine Overheat,

Aborted Engine Start,

Loss of Thrust on Both Engines,

Take-Off Configuration Warning,

Landing Configuration Warning,

Engine Surge or Stall,

Runaway Stabilizer:

  1. Control Colum.....................................................Hold Firmly

  2. Auto Pilot .................(if engaged)......................Disengage

  3. Auto Throttle ............(if engaged)......................Disengage

  4. Control Colum and Thrust Levers..... Control Airplane Pitch attitude and airspeed

  5. Main Electric Stabilizer trim................Reduce control colum forces

  6. If the runaway stops after the autopilot is disengaged: Do not Re-engage the autopiulot or auto-throttle End of Checklist

  7. If the runaway continues after the autopilot is disengaged:

    1. STAB TRIM cutout switches (both) ..............Cutout If the runaway continues: Stabilizer trim wheel...... Grasp and Hold

Unreliable Airspeed:

  1. Auto Pilot ..................(if engaged)......................Disengage

  2. Auto Throttle ............(if engaged)......................Disengage

  3. FD switches (Both) off

Set the following gear-up pitch attitude and thrust:

Flaps extended:

10 and 80% N1

Flaps up

4 and 75% N1

Cabin Altitude Warning

  1. Don oxygen masks and set regulator to 100%

  2. Establish Crew communications

  3. Pressurization mode selector.............................Manual

  4. outflow Valve Switch...........................................Hold in the CLOSE until the outflow VALVE indication shows full closed

  5. If cabin altitude is uncontrollable: Passenger signs...................................................ON PASS OXYGEN switch.........................................ON

    1. Go to the Emergency descent checklist on page 0.1 End of Checklist

Emergency Descent

Engine Fire, Severe Damage or Separation,

Engine Overheat,

Aborted Engine Start,

Loss of Thrust on Both Engines,

Take-Off Configuration Warning,

Landing Configuration Warning,

Engine Surge or Stall,

IRS/ Navigation:

Take-off Modes:

Boeing Takeoff modes, B737 takeoff modes, Boeing &37 information and study guide, Boeing 737. Study guide, Is Boeing safe to fly in?,

LNAV will engage at 50ft if selected on the MCP, Autopilot limit is to engage at 400ft min.

B737 Oral Questions:

Questions to know and understand for the FAA/EASA oral exams conducted for a B737 type rating.

What is the max take-off and landing tailwind component?

10 kts

What is the severe turbulent air penetration speed?

280kts or .76M, which ever is lower.

Which phases of flight do we apply this airspeed? Clb and Des

What do we refer to for Cruise? SP 176

What is the maximum takeoff and landing altitude?

8400 ft, w/High Altitude Switch? High altitude 13500

What can’t we operate during refueling operations? HF radio or WX radar

What are the altimeter accuracy requirements for RVSM airspace?

Before Take-off the altimeters must read within 75ft from the airport elevation and no more than 50ft difference between the two.

The maximum allowable inflight difference between Captain and First Officer altitude displays for RVSM operations is 200ft

The aircraft should not be allowed to overshoot or undershoot by more than 150ft

All exceedance of 300ft or greater must be reported to ATC

What is the max inflight difference between the CA and FO's altitude displays for RVSM operations?

50 ft below 5000ft and 60 ft from 5000ft max difference between CATP an FO

While conducting pre-flight in CVG, CA and FO’s have a 50ft difference. Does this meet RVSM?

Yes. Requirements? What if we were in DEN? Between

If the CA and FO altimeter display the same altitude but differ from Field Elevation by 50ft, are we legal for RVSM?

Yes, max is 75ft from the field elevation.

With either one or more Engine Bleed air switches ON, what position should not be selected for the Air conditioning packs during T/O, Approach, or Landing?

What are the weight limitations?

MLW: $66,360

MTOW: 79,015kg

How to Start a Boeing B737:

The normal starter duty cycle is 2 minutes with 10 seconds needed between starts. Multiple consecutive starts may be attempted.

Announce Start Sequence, PM will turn off Packs, and ensure the cross bleed value is open and APU bleed ON, turn start switch to GND and set CHRON .

ENG 2 will spool up, at 25% N2: ENG Start Lever to IDLE DENT, check fuel valves turn on (bright/dim), FF will increase and EGT will begin to increase.

When N2 at 49% voice recorder will flick to AUTO- makes a noise,

N2 at 56%, the engine is stable and PM will look at the start switch to confirm is has moved to AUTO/OFF and call "Starter Cutt-out".

When both engines are started and the RED EGT ground limit indicators have removed from the EGT indication the PM can do the after-start flow.

Turbine Engine Start Faults

Do the ABORTED ENGINE START checklist when the following occur:

  • the N1 or N2 does not increase or increases very slowly after the EGT increases,

  • there is no oil pressure indication by the time that the engine is stable at idle,

  • the EGT does not increase by 15 seconds after the engine start lever is moved to IDLE detent,

  • The ET quickly nears or exceeds the start limit.

Preflight Setup - Boeing

All aircraft have a flow or sequence of tasks that need to be completed to start and power the systems and engines for flight. I have written a summary of tasks and steps to help those that do not have company operations manuals and FCOMS. All aircraft are different and for this sequence of tasks for this flow, the setup will include an operating ACAR system to produce the performance and flight plan information needed to operate the aircraft and get clearance.

Preflight Setup:

Enter the aircraft, and conduct the security check in the galley, and cockpit.

Check circuit breakers and manual landing gear handles,

Complete IRS initialization, and overhead scan, and set outside lights set, check the parking brake for exterior inspection.

Complete the Walk Around

Set up the CDU- Initial, Position, Route (execute), ARV/DEP (check departure and arrival for discontinuities)/Execute, Init ( Weights-CI-Cruz Level, Temp), N1, Takeoff page 2 then 1 ( NADP height set, cut back off).

Initial ACARS, Initial get ATIS, Set Performance Data, Enter PDC data (send -30).

Initial ACARS: Add CPT,FO ID, check Flight number, check and make Date BIG, Add departure time and ETE(flight time),

PDC: Check the route and flight number, enter AC type: B738, Parking bay: AMZ, send at -30 from Departure. When clearance is received, read and brief off FMS, then print and put in flight folder.

Performance: Enter RWY's, wind, temp, QNH, Flap preferred, Anti Ice, Runway RCAM and Non-Normals. Send data, When received; View Data and exit to print data.

Complete Preflight Scan: Overhead, MCP set (FD and CRS (OEI Route)), Oxygen check to displays and Center Panel, Center Pedestal set.

APU required: Fire check beforehand.

Preflight Checklist

Brief the following when required:


Takeoff SID/Charts/RTO/OEI

Performance when sable reviewed and cross-checked.

Sable information leads to OFP ZFW/TOW being entered and checked for fuel requirements.

Enter ZFW to T/O data ACARS and then brief performance once received T/O data via ACAR's,

CDU Brief,

Ground wants to close the Cargo door, and must pressurize system A ( Beacon on, Elec A on)

When cargo is loaded and doors closed, FO must go check doors are closed and engines for damage.

Captain can confirm clear to close. clear to arm. Close Doors (flags down), clear to arm (arm girt bars), close cockpit , door, and set up for pushback.

Clear to pressurize with nose wheel bypass pin installed is trigger for:

Before start flow: Pumps, Pumps, Light

Before Start Checklist

Get ATC push and start approval,

Push back: ATC set to ALT

Start Engines: Set Eng SD, Packs Off, ISO OPEN, APU bleed ON, Start switches as RQD

Engines started and Captain confirms Gnd to disconnect:

Power to ENG gen, Probe to Auto, Packs ON, ISO Auto, APU bleed off, APU off, Start switches AUTO or CONT, set Flight panel, Ground Clear, Flap.... set, Before Taxi Checklist completed, Taxi clearance and Flash ground crew.

During Taxi:

Set frequencies, WX/TER on as rqd

Before Takeoff Checklist

Before entering Run-Way:

Required fuel is......, ...... onboard.

Entering Runway: lights, camera, action

Lights on for Runway: Scrobe, runway, taxi, and logo

Camera: What we need to see, WX/TERR

Action: ATC- TA/RA

Runway ......, Heading Checks

Cleared for TAKEOFF: Landing Lights ON


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