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Illustrated technical information covering Vol 2 Over 800 multi-choice systems questions Close up photos of internal and external components Illustrated history and description of all variants of 737 Databases and reports of all the major 737 accidents & incidents History and Development of the Boeing 737 - MAX General flightdeck views of each generation of 737's Technical presentations of 737 systems by Chris Brady Detailed tech specs of every series of 737 A collection of my favourite photographs that I have taken of or from the 737 Press reports of orders and deliveries Details about 737 production methods A compilation of links to other sites with useful 737 content Study notes and technical information A compilation of links to major 737 news stories with a downloadable archive A quick concise overview of the pages on this site



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*** Updated 23 Nov 2020 ***

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Note: Not all limitations given here are AFM



Runway slope limits +/-2%
Max takeoff / landing tailwind component 10kts (May be 15kts as customer option)
No tailwind component allowed on contaminated runways.
Max windspeed for taxing 65kts
Turbulent airspeed 1/200:






Max operating altitude 1/500:




Maximum Takeoff and Landing Altitude 8,400ft (12,000ft high altitude option)
Max precipitation depth for takeoff or landing Dry snow 60mm
Water, wet snow, slush 13mm. (AFM=15mm)
Max demonstrated crosswind 1/200:



6/900 winglets:






Flight Manoeuvring Load Acceleration Limits (AFM)

Flaps up +2.5g to -1.0g
Flaps down +2.0g to 0.0g


Altitude Display Limits for RVSM Operations

Standby altimeters do not meet altimeter accuracy requirements of RVSM airspace.
The maximum allowable in-flight difference between Captain and First Officer altitude displays for RVSM operations is 200 feet.
The maximum allowable on-the-ground altitude display differences for RVSM operations are:


Field Elevation Max Diff between Captain & F/O Max Diff between Captain or F/O and Field Elevation
Sea Level 40 ft 75 ft
5,000ft 45 ft 75 ft
10,000ft 50 ft 75 ft


737 NG

Field Elevation Max Diff between Captain & F/O Max Diff between Captain or F/O and Field Elevation
Sea Level to 5,000ft 50 ft 75 ft
5,001 to 10,000ft 60 ft 75 ft


Weight Limitations

    Too many taxi, takeoff, landing & zero fuel limitations to list here.


Air Systems

Max cabin differential pressure (relief valves) 1/500: 8.65 psi

6/900: 9.10 psi

Max cabin diff for takeoff & landing 0.125 psi (236ft below airport PA)
One pack may be inoperative provided maximum altitude is limited to FL250
With engine bleed air switches ON, do not operate the air conditioning packs in HIGH for takeoff, approach or landing.


Anti-Ice & Rain

Engine anti-ice must be on during all ground and flight operations when icing conditions exist or are anticipated, except during climb and cruise below -40C SAT.

Engine anti-ice must be on prior to and during descent in all icing conditions, including temperatures below -40C SAT.

Do not use wing anti-ice on the ground when the OAT is above 10C.



Minimum N1 for operating in icing conditions except for landing: 40% when TAT between 0 and 10C; 55% when TAT below 0C; 70% in moderate to severe icing conditions when TAT below -6.5C.

Window heat inop: max speed 250kts below 10,000ft.

Gravel Protect switch: ANTI-ICE position when using engine inlet anti-ice.


737-6/900 without stiffened elevator tabs:

After any ground deicing/anti-icing of the horizontal stabilizer using Type II or Type IV fluids, airspeed must be limited to 270 KIAS until the crew has been informed that applicable maintenance procedures have been accomplished that would allow exceedance of 270 KIAS. Once the applicable maintenance procedures have been accomplished, exceeding 270 KIAS is permissible only until the next application of Type II or Type IV deicing/anti-icing fluids.



Max windspeed for operation 40kts
May remain extended in winds up to 60kts



Max EGT 760C
Max continuous EGT 710C
Max alt using bleed and electrics 10,000ft
Max alt using bleed only 17,000ft
Max alt using electrics only 35,000ft Garrett

37,000ft Sundstrand

41,000ft 737-NG & MAX

Failed start wait times:
Garrett: No wait after 1st attempt

5mins after 2nd attempt

1hr after 3rd attempt

Sundstrand: 3 attempts then 30min wait
APU bleed valve must be closed when:
  • Ground air connected and isolation valve open
  • Engine no. 1 bleed valve open
  • Isolation and engine no. 2 bleed valves open.

APU bleed valve may be open during engine start, but avoid engine power above idle.


Autopilot/Flight Director System


Use of autopilot not authorised for takeoff or landing.

Do not use the autopilot roll channel above 30,000ft with yaw damper inoperative.

Do not use autopilot pitch channel above 0.81M with hydraulic system A or B depressurised.

Do not use ALT HOLD mode when Captain's alternate static source is selected.



Use of aileron trim with autopilot engaged is prohibited.

Do not engage the autopilot for takeoff below 1000ft AGL.

For single channel operation, the autopilot shall not be engaged below 50ft AGL.

Maximum allowable wind speeds, when conducting a dual channel Cat II or Cat III landing predicated on autoland operations, are:

  • Headwind 25 knots
  • Crosswind 25 knots
  • Tailwind: 10knots
Maximum and minimum glideslope angles are 3.25 degrees and 2.5 degrees respectively.

Autoland capability may only be used with flaps 30 or 40 and both engines operative.



Use of aileron trim with autopilot engaged is prohibited.

Do not engage the autopilot for takeoff below 400ft AGL.

For single channel operation during approach, the autopilot shall not remain engaged below 50ft AGL.

The autopilot must be disengaged before the airplane descends more than 50 feet below the minimum descent altitude (MDA) unless it is coupled to an ILS glide slope and localizer or in the go-around mode. (JAA Rule).


Maximum allowable wind speeds, when conducting a dual channel Cat II or Cat III landing predicated on autoland operations, are:
. Headwind 25 knots
. Crosswind 25 knots
. Tailwind: Varies between 0 and 15kts depending upon field elevation and flap setting.

Maximum and minimum glideslope angles are 3.25 degrees and 2.5 degrees respectively.

Autoland capability may only be used with flaps 30 or 40 and both engines operative.



Do not use VHF-3 (if installed for voice communication) for ATC communications with ACARS operational.
Aircraft Communications Addressing and Reporting System

The ACARS is limited to the transmission and receipt of messages that will not create an unsafe condition if the message is improperly received, such as the following conditions:

. the message or parts of the message are delayed or not received,

. the message is delivered to the wrong recipient, or

. the message content may be frequently corrupted.

However, Pre-Departure Clearance, Digital Automatic Terminal Information Service, Oceanic Clearances, Weight and Balance and Takeoff Data messages can be transmitted and received over ACARS if they are verified per approved operational procedures.


HUD System

Option - With HGS 4000 Phase I: AIII mode approach and landings are not approved for airplanes with Flight Dynamics Model 4000 Phase I HGS installed.

With HGS 2350 and polar navigation: Do not use HUD System at latitudes greater than 85 degrees latitude or when the Heading Reference Switch is in the TRUE position.



TR voltage range 24-30 V
Battery voltage range 22-30 V (May be up to 33V during pulse mode charging)
Max engine gen drive oil temp 157C
Max engine gen drive rise 20C
Max engine gen load (1/200 only) 111 Amps
If aircraft is fitted with a VSCF, must operate within 45mins of a suitable aerodrome.


Flight Controls

Max flap extend altitude: 20,000ft
In flight, do not extend speedbrake lever beyond FLIGHT DETENT.
Holding in icing conditions with flaps extended is prohibited.
Do not deploy the speedbrakes in flight at radio altitudes less than 1,000ft.
Avoid rapid and large alternating control inputs, especially in combination with large changes in pitch, roll, or yaw (e.g. large side slip angles) as they may result in structural failure at any speed, including below VA.
737-6/900 without stiffened elevator tabs: Do not operate the airplane at speeds in excess of 300 KIAS with speedbrakes extended. WARNING: Use of speedbrakes at speeds in excess of 320 KIAS could result in a severe vibration, which, in turn, could cause extreme damage to the horizontal stabilizer.
Alternate flap duty cycle:
Flap Position Minutes Off
0 - 15 5
15 - 40 25


Flight Management, Navigation

Do not operate weather radar near fuel spills or within 15 feet of people.
Air Data Inertial Reference Unit: ADIRU alignment must not be attempted at latitudes greater than 78 degrees 15 minutes.
The use of LNAV or VNAV with QFE selected is prohibited.
FMC U7.2 or earlier: During VOR approaches, one pilot must have raw data from the VOR associated with the approach displayed on the EHSI VOR/ILS mode no later than the final approach fix.
737NG Only: Use of the vertical situation display during QFE operation is prohibited.
Enhanced GPWS:
  • Do not use the terrain display for navigation.
  • Do not use the look-ahead terrain alerting and terrain display functions within 15 nm of takeoff, approach or landing at an airport not contained in the GPWS terrain database



Max temp +49C
Min temp 737-1/500: -45C or freeze pt +3C

737-6/900: -43C or freeze pt +3C

Max lateral imbalance 453kg  (=1,000lbs)

Greater allowance given for unsymmetrical loads in cargo version.

Main tanks must be full if centre contains over 453kg
For ground operation, centre tank pumps must be not be positioned to ON, unless defuelling or transferring fuel, if quantity is below 453kgs.
Centre tank pumps must be switched OFF when both LP lights illuminate.
Centre tank pumps must not be left ON unless personnel are available in the flight deck to monitor LP lights.
Fuel crossfeed valve must be closed for takeoff and landing. (737NG only)


Hydraulic Power

Minimum of 760kg fuel required in respective tank for hydraulic pump operation.

Minimum of 88% required for despatch.


Landing Gear

Do not apply brakes until after touchdown.
Operation with assumed temperature reduced takeoff thrust is not permitted with anti-skid inoperative.
Max speed, gear extension 270kt/0.82
Max speed, gear retraction 235kt
Max speed, gear extended 320kt/0.82


Performance Data Computer System (1/200 Only)

Do not use the PDCS information unless the engine configuration displayed on the PDCS is the same as the engine configuration of the airplane.

Fuel management and range calculations presented by the PDCS have not been evaluated by the FAA.

Verify that the representative takeoff EPR limits displayed on the CDU and EPR indicators agree with the predetermined limits obtained from the flight manual.



Max external air pressure 60 psig
Max external air temp 232C


Power Plant

JT8D-9 JT8D-17A CFM56-3 CFM56-7
Max time for take-off or go-around thrust: 5 mins 5 mins 5 mins 5 mins
Max N1 100.1% 102.4% 106% 104%
Max N2 100.0% 100.0% 105% 105%
Max EGT's:
Take-off 580C 650C 930C 950C
Continuous 540C 610C 895C 925C
Start 350/420C 575C 725C 725C
Oil T's & P's
Max temperature 165C 155C
15 minute limit 121-157C 131-165C 160-165C 140-155C
Max continuous 120C 130C 160C 140C
Min oil press 40psi 40psi 13psi (warning light), 26psi (gauge) 13psi (warning light), 26psi (gauge)
Min oil qty (at despatch) 3 US Gal or 75% full 3 US Gal or 75% full

CFM56-7 limits: Maximum and minimum limits are red. Caution limits are amber.

Pneumatic pressure prior to starter engagement: 30psi -1/2psi per 1000' amsl. (737-1/500 Only)

Starter duty cycle 1st attempt: 2min on, 20sec off

2nd & subsequent attempt: 2min on, 3min off

Engine ignition must be on for: Takeoff, Landing, Operation in heavy rain and Anti-ice operation.

Intentional selection of reverse thrust in flight is prohibited.


Wind Limits for T/O & Landing

Braking Action Max X-wind Motne Coefficient
Good 35kt 95 0.4+
Med/good 30kt 94 0.39-0.36
Medium 25kt 93 0.35-0.3
Med/poor 20kt 92 0.29-0.26
Poor 15kt 91 0.25 & less
Note 1. Different (reduced) x-wind guidelines are available for 30m wide runways.

Note 2. Maximum windspeed for taxying is 65kts


Contaminated Runways

Max depths as follows
Dry snow 60mm NB Above -5C snow is to be considered as slush.
Wet snow 13mm
Compacted snow / Slush 13mm
Standing water 13mm


Min Width for Snow Clearance

Width Depth
Central 30m 13mm
Next 8m (38) 23cm
Next 16m (54m width) 38cm
Beyond 54m 120cm




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