P.O. BOX 790490 • SAN ANTONIO, TEXAS 78279-0490 • (210) 824-9421

SUBJECT: REVISION B-29 TO SA226-T(B) AFM

TO: ALL OPERATORS AND AFM MANAGERS OF THE SA226-T(B)

1. Attached is Revision B-29 to Sections i and 3 of your AFM.

2. File this transmittal letter in your AFM binder at the location most convenient to you.
P.O. Box 790490 • San Antonio, Texas 78279–0490 • (210) 824–9421
iii Issued: November 3, 1978

Reissued: November 2, 1979

MERLIN SA226-T(B)

FAA APPROVED AIRPLANE FLIGHT MANUAL

REISSUE B

S/N T(B) - 276 AND T(B) - 292 AND SUBSEQUENT

LIST OF EFFECTIVE PAGES

Page Date Page Date

SECTION 1

Page Date Page Date

SECTiON 2

Page Date Page Date

Title .................................... September 14, 1995

 i ............................................ November 2, 1979

 ii ........................................... November 2, 1979

 iii ........................................ November 14, 2014

 iv ........................................ November 14, 2014

 v ......................................... November 29, 2005

 vi ...................................................July 14, 1981

 vii .................................................. June 3, 1980

 viii ............................................. March 12, 1981

 ix ................................................. June 21, 1983

 x ............................................. October 16, 1997

 xi .................................................. May 28, 2008

 xii ....................................... November 14, 2014

1-i.......................................... November 2, 1979

1-ii ......................................... November 2, 1979

1-1 ........................................ November 2, 1979

1-2 ........................................ November 2, 1979

1-3 ........................................ November 2, 1979

1-4 ........................................ November 2, 1979

1-5 ....................................... September 3, 2013

1-6 ....................................... September 3, 2013

1-7 ....................................... September 3, 2013

1-8 ........................................ November 2, 1979

1-9 ........................................ November 2, 1979

1-10 ...................................... November 2, 1979

1-11 ....................................... November 2, 1979

1-12 ...................................... November 2, 1979

1-13 ...................................... November 2, 1979

1-14 ...................................... November 2, 1979

1-15 ...................................... November 2, 1979

1-16 ...................................... November 2, 1979

2-i.......................................... December 7, 2007

2-ii ......................................... November 2, 1979

2-1 ................................................. June 3, 1980

2-2 ............................................... June 21, 1983

2-3 ............................................... June 21, 1983

2-4 ........................................ November 2, 1979

2-5 ....................................... September 3, 2013

2-6 ........................................ November 2, 1979

2-7 ................................................. June 3, 1980

2-8 ........................................ December 7, 2007

2-9 ........................................ December 7, 2007

2-10 ........................................ October 16, 1997

2-10A ............................................. June 2, 2000

2-10B ............................................. June 2, 2000

2-11 ......................................... October 16, 1997

2-12 ........................................ January 14, 1982

2-13 ........................................... March 12, 1981

2-14 ............................................... June 3, 1980

2-15 ...................................... November 2, 1979

2-16 ...................................... November 2, 1979

Issued: November 2, 1979 LIST OF EFFECTIVE PAGES

Revised: November 14, 2014
iv Issued: November 3, 1978

Reissued: November 2, 1979

MERLIN SA226-T(B)

FAA APPROVED AIRPLANE FLIGHT MANUAL

REISSUE B

S/N T(B) - 276 AND T(B) - 292 AND SUBSEQUENT

LIST OF EFFECTIVE PAGES (continued)

SECTION 3

Page Date Page Date

SECTION 3A

Page Date Page Date

3-i........................................ November 14, 2014

3-ii ....................................... November 14, 2014 

3-1 ..................................................May 11,1999

3-2 ...................................... November 14, 2014

3-3 ...................................... November 14, 2014

3-4 ...................................... November 14, 2014

3-5 ...................................... November 14, 2014

3-6 ...................................... November 14, 2014

3-7 ...................................... November 14, 2014 

3-8 ...................................... November 14, 2014

3-9 ...................................... November 14, 2014

3-10 .................................... November 14, 2014

3-11 ..................................... November 14, 2014

3-12 .................................... November 14, 2014

3-13 .................................... November 14, 2014

3-14 .................................... November 14, 2014

3-15 .................................... November 14, 2014

3-16 .................................... November 14, 2014

3-17 .................................... November 14, 2014

3-18 .................................... November 14, 2014

3-19 .................................... November 14, 2014

3-20 .................................... November 14, 2014

3-21 .................................... November 14, 2014 

3-22 .................................... November 14, 2014

3-23 .................................... November 14, 2014 

3-24 .................................... November 14, 2014

3A-11 ...................................... October 24, 1980

3A-12 ...................................... October 24, 1980

3A-13 ......................................... March 12, 1981

3A-14 ...................................... October 24, 1980

3A-15 ......................................... March 12, 1981

3A-16 ...................................... October 24, 1980

3A-17 ......................................... March 12, 1981

3A-18 ................................. September 14, 1995

3A-18a ............................... September 14, 1995

3A-18b ............................... September 14, 1995

3A-19 ...................................... October 24, 1980

3A-20 ...................................... October 24, 1980

3A-21 ...................................... October 24, 1980

3A-22 ...................................... October 24, 1980

3A-23 ...................................... October 24, 1980

3A-24 ...................................... October 24, 1980

3A-i ....................................... December 7, 2007

3A-ii ...................................... November 2, 1979

3A-1 ........................................ October 24, 1980

3A-2 .........................................February 3, 1983

3A-3 ........................................ October 24, 1980

3A-4 ........................................ October 24, 1980

3A-5 ........................................ October 24, 1980

3A-6 ...................................... December 7, 2007

3A-6A .................................... December 7, 2007

3A-6B.................................... December 7, 2007

3A-7 ........................................ October 24, 1980

3A-8 ........................................ October 24, 1980

3A-9 ........................................ October 24, 1980

3A-10 ...................................... October 16, 1997

3A-10A ........................................... June 2, 2000

3A-10B.................................... October 16, 1997

LIST OF EFFECTIVE PAGES Issued: November 2, 1979

Revised: November 14, 2014


EMERGENCY PROCEDURES 3-i

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

MERLIN III B

TABLE OF CONTENTS

ITEM PAGE

Introduction ...................................................................................................................................... 3-1

Engine Fire on Ground .................................................................................................................... 3-2

Engine Fire in Flight......................................................................................................................... 3-2

Out-of-Trim Warning ........................................................................................................................ 3-2

Engine Failure During Takeoff – Takeoff Aborted ............................................................................ 3-3

Engine Failure During Takeoff – Takeoff Continued at or Above VR ............................................... 3-3

Engine Failure During Flight ............................................................................................................ 3-4

Engine - Propeller Uncoupling ......................................................................................................... 3-5

Airstart ............................................................................................................................................. 3-5

Single Engine Landing..................................................................................................................... 3-6

 After Touchdown ..................................................................................................................... 3-6 

Single Engine Go-Around ................................................................................................................ 3-7

Engine Control Malfunction ............................................................................................................. 3-7

No Response to Power Lever Movement ........................................................................................ 3-7

Battery Overheat Warning Light On During Ground Operations ..................................................... 3-8

Battery Overheat Warning Light On During Flight ........................................................................... 3-8

Double Generator Failure ................................................................................................................ 3-9

Double Engine Failure (Restarts/Relights Unsuccessful) ................................................................ 3-9

Total Electrical Failure ................................................................................................................... 3-10

Smoke in Airplane.......................................................................................................................... 3-10

Wheelwell and Wing Overheat Warning Light On ..........................................................................3-11

 Steady Light ...........................................................................................................................3-11

 Flashing Light ....................................................................................................................... 3-12

Cabin Pressurization Malfunctions ................................................................................................ 3-12

 Low Pressure Malfunction .................................................................................................... 3-12

 High Pressure malfunction ................................................................................................... 3-12

 Excessive Rate of Pressurization ......................................................................................... 3-13

Emergency Descent Procedure..................................................................................................... 3-14

Cabin Door Warning Light On ....................................................................................................... 3-14

 Prior to Takeoff ...................................................................................................................... 3-14

 In Flight ................................................................................................................................. 3-14

Hydraulic System Failure............................................................................................................... 3-14

Landing Gear Emergency Extension ............................................................................................. 3-15

Gear Up Landings ......................................................................................................................... 3-15

Stabilizer Trim Malfunctions........................................................................................................... 3-17

 Stabilizer Trim System Runaway .......................................................................................... 3-17

 Pilot's Trim Sytem Inoperative .............................................................................................. 3-17

 Copilot's Trin System Inoperative ......................................................................................... 3-17

 Both Pilot's and Copilot's Trim System Inoperative .............................................................. 3-17

 Go-Around with Stabilizer Trim Inoperative .......................................................................... 3-18

Stability Augmentation and Stall Avoidance System (SAS2) Malfunctions .................................... 3-19

 SAS2 Malfunction – Nose Down .......................................................................................... 3-20

 Aural Stall Warnings at Speeds Well in Excess of Normal Stall Warning Speeds ................ 3-21
3-ii EMERGENCY PROCEDURES

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

MERLIN III B

TABLE OF CONTENTS (continued)

ITEM PAGE

Yaw Damper/Rudder Bias Malfunctions ........................................................................................ 3-21

 Power Failure ....................................................................................................................... 3-21

 Electrical Servo Runaway ..................................................................................................... 3-21

Emergency Exit ............................................................................................................................. 3-21

Nose Wheel Steering Malfunction ................................................................................................. 3-22

Nose Wheel Steering Electrical Malfunction (On those aircraft which have

 been modifi ed in accordance with Service Bulletin 32-037) ...................................................... 3-22

Nose Wheel Steering Hydraulic Malfunction ................................................................................. 3-23
EMERGENCY PROCEDURES 3-1

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

INTRODUCTION

Section 3 of this handbook covers emergencies that could possibly occur during ground or 

fl ight operation and the recommended procedures for correcting the situation. The emergency 

situations covered are placed in the order of the most serious fi rst, i.e., Fires, Engine Failure, etc. 

The IMMEDIATE ACTION items, which must be performed fi rst, are in BOLD CAPITAL letters with 

the remaining steps (clean up procedures) following. Expanded procedures are covered in this 

section. The emergency procedures in this section have been FAA approved.

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: May 11, 1999
Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

3-2 EMERGENCY PROCEDURES

MERLIN III B

ENGINE FIRE ON GROUND

1. ENGINE STOP AND FEATHER CONTROL (affected engine) ..................................... PULL

 2. ENGINE STOP BUTTON (affected engine) ................................................................ PRESS 

 3. FUEL SHUTOFF SWITCH (affected engine) ...........................................................CLOSED 

 4. HYDRAULIC SHUTOFF SWITCH (affected engine) ................................................CLOSED 

 5. FIRE EXTINGUISHER SWITCH (affected engine) ..................................................... PRESS

 6. Starter Test Switch (affected engine) ......................................................................... ENGAGE

 7. Fuel Boost Pump Switch (affected engine) ........................................................................ OFF

 9. Affected Engine ...........................................................MOTOR UNTIL ENGINE IS CLEARED

ENGINE FIRE IN FLIGHT

WARNING

IN THE EVENT OF AN ENGINE FAILURE OR POWER LOSS, 

THE ENGINE NEGATIVE TORQUE SYSTEM (NTS) ONLY 

PROVIDES PARTIAL DRAG REDUCTION BUT NOT TO THE 

EXTENT OF A FULLY FEATHERED PROPELLER. 

PILOT MUST TAKE ACTION TO FULLY FEATHER THE PROPELLER (ON THE AFFECTED ENGINE) TO REDUCE PROPELLER DRAG.

1. ENGINE STOP AND FEATHER CONTROL (affected engine) ..................................... PULL

 2. FUEL SHUTOFF SWITCH (affected engine) ...........................................................CLOSED

 3. HYDRAULIC SHUTOFF SWITCH (affected engine) ................................................CLOSED

 4. FIRE EXTINGUISHER SWITCH (affected engine) ..................................................... PRESS

 5. Fuel Boost Pump Switch (affected engine) ........................................................................ OFF

 6. Generator Switch (affected engine) ................................................................................... OFF

 7. Bleed Air Switch (affected engine) ..................................................................................... OFF

 8. Power Lever (operating engine) .......................................................................AS REQUIRED

 9. Bleed Air (operating engine) .............................................................................AS REQUIRED

NOTE

If the 100% torque limit is not being developed and bleed air is 

on, increased power may be obtained by selecting bleed air off.

 10. Trim ...................................................................................................................AS REQUIRED 

 11. Generator (operating engine) ................................................................ 300 AMPS MAXIMUM 

 12. Propeller Synchrophaser Switch ........................................................................................ OFF

OUT-OF-TRIM WARNING

 AURAL OUT-OF-TRIM WARNING ............................................................ABORT TAKEOFF

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014
EMERGENCY PROCEDURES 3-3

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

ENGINE FAILURE DURING TAKEOFF – TAKEOFF ABORTED

 1. POWER LEVERS ............................................................................................ GROUND IDLE

2. BRAKES ...........................................................................................................AS REQUIRED

 3. Nose Wheel Steering ........................................................................................AS REQUIRED

 4. Reverse Thrust (operating engine) ...................................................................AS REQUIRED

(BELOW 40 KNOTS)

CAUTION

ON WET OR SLIPPERY SURFACES, USE CAUTION WHEN REVERSING ONLY ONE ENGINE.

 5. Engine Stop and Feather Control (failed engine) .............................................................PULL 

 6. Engine Clean Up Procedure (failed engine)

 a. Fuel shutoff switch ................................................................................................CLOSED

 b. Hydraulic shutoff switch ........................................................................................CLOSED

 c. Fuel boost pump switch ............................................................................................... OFF

 d. Generator switch .......................................................................................................... OFF

 e. Bleed air switch ............................................................................................................ OFF

ENGINE FAILURE DURING TAKEOFF – TAKEOFF CONTINUED

AT OR ABOVE VR

WARNING

IN THE EVENT OF AN ENGINE FAILURE OR POWER LOSS, 

THE ENGINE NEGATIVE TORQUE SYSTEM (NTS) ONLY 

PROVIDES PARTIAL DRAG REDUCTION BUT NOT TO THE 

EXTENT OF A FULLY FEATHERED PROPELLER. 

PILOT MUST TAKE ACTION TO FULLY FEATHER THE PROPELLER (ON THE AFFECTED ENGINE) TO REDUCE PROPELLER DRAG.

 1. POWER LEVER (operating engine) ................................................ SET TAKEOFF POWER

NOTE

• Retarding the power lever of the inoperative engine aft of the 

quadrant switch will disable the rudder bias system.

• Commanding high propeller blade angle by keeping the 

power lever of the inoperative engine well forward will reduce 

windmilling propeller drag in the event that NTS failure accompanies engine failure.

• Set 650oC ET or 100% torque, whichever occurs fi rst. If the 

100% torque limit is not being developed and bleed air is ON, 

increased power may be obtained by selecting bleed air OFF.
Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

3-4 EMERGENCY PROCEDURES

MERLIN III B

ENGINE FAILURE DURING TAKEOFF – TAKEOFF CONTINUED

AT OR ABOVE VR (continued)

 *2. LANDING GEAR (after liftoff) ................................................................................ RETRACT

WARNING

IF THE ENGINE FAILURE IS ACCOMPANIED BY A LEFT ESSENTIAL BUS FAILURE (AS INDICATED BY LOSS OF POWER 

TO THE GEAR POSITION INDICATOR) THE LANDING GEAR 

WILL NOT RETRACT UNTIL THE LANDING GEAR CONTROL 

ESSENTIAL BUS POWER TRANSFER IS MOVED TO THE RIGHT 

BUS POSITION.

*3. FLAPS ..................................................................................................................... RETRACT 

 4. ENGINE STOP AND FEATHER CONTROL (failed engine). ......................................... PULL

 5. AIRSPEED .....................................................SINGLE ENGINE BEST RATE CLIMB SPEED

135 KIAS (138 KCAS) 

 6. Engine Clean Up Procedure (failed engine)

 a. Fuel shutoff switch ................................................................................................CLOSED

 b. Hydraulic shutoff switch ........................................................................................CLOSED

 c. Fuel boost pump switch ............................................................................................... OFF

 d. Generator switch .......................................................................................................... OFF

 e. Bleed air switch ............................................................................................................ OFF

 7. Power Lever (operating engine) .......................................................................AS REQUIRED 

 8. Trim ...................................................................................................................AS REQUIRED 

 9. Generator (operating engine) ................................................................ 300 AMPS MAXIMUM 

 10. Propeller Synchrophaser ................................................................................................... OFF

ENGINE FAILURE DURING FLIGHT

WARNING

IN THE EVENT OF AN ENGINE FAILURE OR POWER LOSS, 

THE ENGINE NEGATIVE TORQUE SYSTEM (NTS) ONLY 

PROVIDES PARTIAL DRAG REDUCTION BUT NOT TO THE 

EXTENT OF A FULLY FEATHERED PROPELLER. 

PILOT MUST TAKE ACTION TO FULLY FEATHER THE PROPELLER (ON THE AFFECTED ENGINE) TO REDUCE PROPELLER DRAG.

 1. ENGINE STOP AND FEATHER CONTROL (failed engine) .......................................... PULL 

 2. Engine Clean Up Procedure (failed engine)

 a. Fuel shutoff switch ................................................................................................CLOSED

 b. Hydraulic shutoff switch ........................................................................................CLOSED

 c. Fuel boost pump switch ............................................................................................... OFF

 d. Generator switch .......................................................................................................... OFF

 e. Bleed air switch ............................................................................................................ OFF

 3. Power Lever (operating engine) .......................................................................AS REQUIRED

 4. Bleed Air (operating engine) .............................................................................AS REQUIRED

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014
EMERGENCY PROCEDURES 3-5

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

ENGINE FAILURE DURING FLIGHT (continued)

NOTE

If the 100% torque limit is not being developed and bleed air is 

on, increased power may be obtained by selecting bleed air off.

 5. Trim ...................................................................................................................AS REQUIRED

 6. Generator (operating engine) ................................................................ 300 AMPS MAXIMUM

 *7. Propeller Synchrophaser Switch (if instlled) .........................................TAKEOFF & LANDING

ENGINE - PROPELLER UNCOUPLING

WARNING 

• IN THE EVENT OF ENGINE FAILURE IN CONJUNCTION 

WITH ENGINE UNCOUPLING, REDUCE WINDMILLING 

DRAG AS FOLLOWS:

• IF AN UNCOUPLING EVENT OCCURS WHERE THE ENGINE IS OPERATING AND THE PROPELLER IS STOPPED 

AND FEATHERED, RETARDING THE POWER LEVER 

TO FLIGHT IDLE MAY RESULT IN UNFEATHERING AND 

SUBSEQUENT ROTATION OF THE PROPELLER. IF THIS 

OCCURS, ADVANCE THE POWER LEVER TO MAXIMUM 

POWER POSITION.

• IN THE EVENT OF AN ENGINE WITH AN NTS AND/OR 

FEATHER VALVE MALFUNCTION, SETTING THE ASSOCIATED POWER LEVERS FULL FORWARD WILL DRIVE THE 

PROPELLER BLADES TOWARD THE FEATHER POSITION 

YIELDING A LOWER WINDMILLING PROPELLER DRAG 

AND PROPELLER SHAFT SPEED.

AIRSTART

CAUTION

IF AN ENGINE HAS BEEN SHUT DOWN BECAUSE OF AN OBVIOUS FAILURE, AS INDICATED BY THE ENGINE IN- STRUMENTS 

OR EXCESSIVE VIBRATION, AN AIRSTART SHOULD NOT BE 

ATTEMPTED. AIRSTART FOLLOWING INTENTIONAL ENGINE 

SHUTDOWN IS COVERED IN SECTION 3A, ABNORMAL PROCEDURES.
Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

3-6 EMERGENCY PROCEDURES

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

SINGLE ENGINE LANDING

WARNING

IN THE EVENT OF AN ENGINE FAILURE OR POWER LOSS, 

THE ENGINE NEGATIVE TORQUE SYSTEM (NTS) ONLY 

PROVIDES PARTIAL DRAG REDUCTION BUT NOT TO THE 

EXTENT OF A FULLY FEATHERED PROPELLER. 

PILOT MUST TAKE ACTION TO FULLY FEATHER THE PROPELLER (ON THE AFFECTED ENGINE) TO REDUCE PROPELLER DRAG.

 *1. No Smoking – Fasten Seat Belt Sign .................................................................................. ON

 2. Fuel Quantity ........................................................CHECK WITHIN 500 LBS. DIFFERENTIAL

NOTE

If excess fuel imbalance is indicated on fuel quantity gauge, 

confi rm by checking trim position as gauge may be incorrect. 

If excess imbalance exists, open fuel crossfl ow switch to balance 

fuel within tolerances.

 3. Fuel Crossfl ow Switch .........................OPEN IF REQUIRED TO BALANCE, THEN/CLOSED

 4. Cabin Differential Pressure ..............................................................................................ZERO

 5. Electrical Load ................................................................TURN OFF NONESSENTIAL ITEMS

 6. Speed Lever (operating engine) .......................................................................................HIGH

 7. Flaps ......................................................................................DO NOT EXTEND BEYOND 1/2

 UNTIL LANDING IS ASSURED

 8. Landing Gear .......................................................... EXTEND WHEN LANDING IS ASSURED

 9. Nose Wheel Steering ....................................................................................................ARMED

NOTE

If nose wheel steering is inoperative see Section 5, Performance 

Section, page 5-25, for increased landing distance requirements.

 10. Ignition Mode Switches .....................................................................................AS REQUIRED

AFTER TOUCHDOWN

 1. Brakes ...............................................................................................................AS REQUIRED

 2. Nose Wheel Steering ........................................................................................AS REQUIRED

 3. Reverse Thrust .................................................................................................AS REQUIRED

(BELOW 40 KNOTS)
EMERGENCY PROCEDURES 3-7

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

Issued: November 3, 1978

AFTER TOUCHDOWN (continued)

CAUTION

ON WET OR SLIPPERY SURFACES, USE CAUTION WHEN REVERSING ONLY ONE ENGINE.

SINGLE ENGINE GO-AROUND

WARNING

IN THE EVENT OF AN ENGINE FAILURE OR POWER LOSS, 

THE ENGINE NEGATIVE TORQUE SYSTEM (NTS) ONLY 

PROVIDES PARTIAL DRAG REDUCTION BUT NOT TO THE 

EXTENT OF A FULLY FEATHERED PROPELLER. 

PILOT MUST TAKE ACTION TO FULLY FEATHER THE PROPELLER (ON THE AFFECTED ENGINE) TO REDUCE PROPELLER DRAG.

 1. Power ................................................................................................................AS REQUIRED

 2. Landing Gear ............................................................................................................RETRACT

 3. Flaps ........................................................................................... RETRACT IN INCREMENTS

 4. Airspeed .....................................................SINGLE ENGINE BEST RATE OF CLIMB SPEED

135 KIAS (138 KCAS)

 *5. Bleed Air Switch ................................................................................................................. OFF

 6. Engine Anti-Ice ................................................................................OFF UNLESS REQUIRED

ENGINE CONTROL MALFUNCTION

In the event there is an indication of improper operation of a fuel control or propeller control, it is recommended that the affected engine be shut down and a single engine landing accomplished.

NO RESPONSE TO POWER LEVER MOVEMENT

If either engine (or both) exhibits a lack of response to the power lever after extended operation at 

high altitude with OAT below freezing, the cause may be ice blockage of the PT2 inlet sensor probe. 

In certain fl ight conditions, when engine anti-ice would not normally be ON, probe icing can occur 

even though visible moisture is not present. If lack of power lever response is observed, the following 

procedure should be accomplished:

 1. Ignition Switches ............................................................................................................. CONT

 2. Engine Heat Switch(es) ......................................................................ENGINE & PROP HEAT

This will introduce anti-icing air to the sensors (as well as the engine inlet) and normal power lever 

response should return within approximately 3 minutes.
Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

3-8 EMERGENCY PROCEDURES

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

NO RESPONSE TO POWER LEVER MOVEMENT (continued)

After the condition has cleared and normal operation is observed, anti-ice and ignition can again be 

turned OFF.

 1. Engine Heat Switch(es) ....................................................................................AS REQUIRED

 2. Ignition Switches ..............................................................................................................AUTO

BATTERY OVERHEAT WARNING LIGHT ON DURING GROUND OPERATIONS

 1. Battery Switch (affected side) ............................................................................................ OFF

 2. Battery Disconnect ....................................................NOTE DISCONNECT INDICATION FOR

AFFECTED SIDE

WARNING

• IF POSITIVE DISCONNECT IS NOT VERIFIED, SHUT 

DOWN ENGINES AND INSPECT BATTERY AS SOON AS POSSIBLE.

• TAKEOFF AFTER A BATTERY TEMPERATURE WARNING 

LIGHT ILLUMINATES IS PROHIBITED UNTIL THE CAUSE 

OF THE OVERHEAT WARNING IS CORRECTED.

NOTE

• The battery overheat sensor triggers at 150° ±3°F. After heat 

soaking in hot climatic conditions, the additional heat generated at 

the batteries during engine start and subsequent recharging may 

cause a nuisance warning light.

• A battery overheat warning light caused by thermal runaway 

may sometimes be verifi ed by observing sustained and excessively 

high generator loads when the affected battery switch is on.

• Leaving the battery switch off for several minutes following 

a nuisance warning may allow the battery to cool enough to 

allow the warning light to extinguish.

BATTERY OVERHEAT WARNING LIGHT ON DURING FLIGHT

 1. Battery Switch (affected side) ............................................................................................ OFF

 2. Battery Disconnect ................................NOTE DISCONNECT INDICATION FOR AFFECTED 

BATTERY AND LAND AS SOON AS PRACTICABLE
EMERGENCY PROCEDURES 3-9

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

BATTERY OVERHEAT WARNING LIGHT ON DURING FLIGHT (continued)

WARNING

IF POSITIVE DISCONNECT IS NOT VERIFIED, LAND AS 

SOON AS POSSIBLE.

DOUBLE GENERATOR FAILURE

1. Both Generator Switches ................................................................................................... OFF

 2. Electrical Load ........................................................................................................... REDUCE

 3. Generator and Start Control Circuit Breakers ...............................................................CHECK

 4. Left Generator Switch ............................................................... RESET/VOLTAGE CHECKED

 5. Left Generator Switch .......................................................................................................... ON

 If left generator will not go on line, turn it OFF and try the right generator.

NOTE

If one of the two generators can be put on line, consideration

should be give to continuing the fl ight with a single generator

rather than risking a second double generator failure.

 5. Right Generator Switch ............................................................. RESET/VOLTAGE CHECKED

 6. Right Generator Switch ........................................................................................................ ON

NOTE

• If neither generator is within limits, it is acceptable to put a single

 generator on line.

• If neither generator can be put on line, all electrical systems (except

 auxiliary air conditioning systems) will be functional on battery

 power. However, eleectrical loads should be quickly reduced to the 

minimum for existing fl ight conditions to prolong battery life.

WARNING

WHEN IN FLIGHT ON BATTERY POWER ALONE, LAND AS 

SOON AS PRACTICAL TO PRECLUDE COMPLETE ELECTRICAL FAILURE.

DOUBLE ENGINE FAILURE (RESTARTS/RELIGHTS UNSUCCESSFUL)

 1. AIRSPEED .................................................................... MAINTAIN BEST GLIDE AIRSPEED

GLIDE AIRSPEED

WEIGHT (POUNDS) 12,000 10,000 8,500

AIRSPEED (KIAS) 148 136 126
Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

3-10 EMERGENCY PROCEDURES

MERLIN III B

 DOUBLE ENGINE FAILURE (RESTARTS/RELIGHTS UNSUCCESSFUL)

(continued)

NOTE

• Best glide airspeed is approximately 1.5 V/VS on the SAS indicator.

• Glide ratio at best glide airspeed is approximately 10:1 

(2NM/1,000FT AGL)

 2. GEAR ...................................................................................................................................UP

 3. FLAPS ..................................................................................................................................UP

 4. Complete Engine failure During Flight Checklist

 Plan for emergency gear extension and a zero fl ap landing. If altitude above ground level 

(AGL) permits, unfeathering one engine may provide suffi cient hydraulic pressure to opertate 

the fl aps.

TOTAL ELECTRICAL FAILURE

 1. Entrance Light Switch ................................................. ON (IF ILLUMINATION IS REQUIRED)

NOTE

The pilot's overhead and entrance door fl ood lights are powered 

by the right battery relay when the entrance light switch is in its ON 

position.

 2. Both Battery and Both Generator Switches ....................................................................... OFF

 3. Battery Switches (individually) ................................................................................ RESET/ON

 4. Generator Switches (individually) ........................................................................... RESET/ON

If total electrical failure occurred as a result of lightning strike or static discharge, the aircraft should 

be thoroughly inspected for evidence of lightning damage. See the SA227 Maintenance Manual, 

Chapter 05 and the TPE 331 Maintenance Manual, Chapter 72.

SMOKE IN AIRPLANE

1. CREW OXYGEN MASKS .................................................................................................DON

2. If Smoke or Fire from Electrical Source:

 a. Smoke or fi re from essential bus

 (1) Bus tie switch ........................................................................................................ OFF

 (2) Bus transfer switches .................................................... OPPOSITE ESSENTIAL BUS

 b. Smoke or fi re from nonessential bus

 • Bus tie switch ........................................................................................................ OFF

 3. If Smoke from Bleed Air Source:

 • Bleed air switches .................... TURN OFF ONE SOURCE. IF SMOKE CONTINUED, 

TURN BACK ON AND TURN OTHER SOURCE OFF. IF 

UNSUCCESSFUL, TURN OFF BOTH SOURCES

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014
EMERGENCY PROCEDURES 3-11

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

SMOKE IN AIRPLANE (continued)

NOTE

It is unlikely that both bleed air systems would malfunction 

simultaneously. However, if they should, closing both bleed air valves 

would prevent more smoke from entering the cockpit and cabin. But 

the outfl ow valve would then close in order to retain cabin differential 

pressure and the existing smoke would be trapped until depressuring 

procedures are begun.

 4. If Smoke in Rear of Airplane .......... USE MANUAL PRESSURIZATION AND SELECT FULL 

DECREASE. WHEN PRESSURE DIFFERENTIAL IS 

ZERO ACTIVATE CABIN DUMP SWITCH.

 5. If Smoke is in Cockpit ........................................................ACTIVATE CABIN DUMP SWITCH

 6. Emergency Descent .........................................................................................AS REQUIRED

 7. Airspeed ...............................................................................173 KIAS (176 KCAS) MAXIMUM

 8. Landing Gear ..............................................................................................................EXTEND

 9. Fresh Air Fan ..........................................................................................................OVERRIDE

NOTE

• If failure occurs in the pneumatic or electrical system of the 

bleed air control valve, the engine may have to be shut down 

to stop the fl ow of bleed air.

• If an engine must be shut down to eliminate bleed air from 

entering the cockpit and cabin, the landing gear should be retracted 

to ensure adequate single engine performance.

• Whether or not smoke has dissipated, if it cannot be visibly 

verifi ed that the fi re has been extinguished following fi re suppression and/or smoke evacuation procedures, land immediately at the 

nearest suitable airport.

WHEELWELL AND WING OVERHEAT WARNING LIGHT ON

STEADY LIGHT (indicates brake fi re, wheelwell or air conditioning duct overheat) 

*1. BLEED AIR SWITCH (affected side) .............................................................................. OFF 

 2. LANDING GEAR ........................................................................................................... DOWN

 Leave gear extended at least three (3) minutes to allow cooling of overheated brakes in 

order to preclude a brake/tire fi re and tire explosion.

3. GENERATOR SWITCH (affected side) ........................................................................... OFF

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014
Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

3-12 EMERGENCY PROCEDURES

MERLIN III B

WHEELWELL AND WING OVERHEAT WARNING LIGHT ON (continued)

NOTE

If the warning light extinguishes, retract the landing gear after three 

(3) minutes cooling and continue fl ight with the bleed air OFF; the 

generator may be RESET/ON. If the light reilluminates STEADY, 

extend the gear. Expect performance degradation due to the drag of 

the gear. A diversion and precautionary landing may be necessary. 

If the light changes to a FLASHING mode complete the wheelwell 

wing overheat fl ashing items.

CAUTION

IF THE WARNING LIGHT DOES NOT EXTINGUISH WITHIN 

THREE MINUTES, THE AFFECTED ENGINE SHOULD BE 

SHUT DOWN. THE LANDING GEAR MAY HAVE TO BE RETRACTED TO SUSTAIN FLIGHT UNTIL ARRIVING AT A SUITABLE 

LANDING FIELD. 

FLASHING LIGHT (indicates a wing leading edge bleed air line failure or an overheated generator 

wire) 

*1. BLEED AIR SWITCH (affected side) .............................................................................. OFF

2. GENERATOR SWITCH (affected side) ........................................................................... OFF

CAUTION

IF THE WARNING LIGHT DOES NOT EXTINGUISH WITHIN 

THREE MINUTES, THE AFFECTED ENGINE SHOULD BE 

SHUT DOWN. 

CABIN PRESSURIZATION MALFUNCTIONS

LOW PRESSURE MALFUNCTION

The cabin altitude warning light illuminates when the cabin pressure is equivalent to a pressure altitude between 10,000 feet and 12,000 feet. Check differential pressure and the controller setting. If 

the cabin pressurization is not providing proper cabin pressure, change to manual operation. If the 

desired differential pressure still cannot be attained, and excessive leak exists and it may be necessary to descend or use oxygen.

HIGH PRESSURE MALFUNCTION

If the cabin differential pressure exceeds the normal limit of 7 psi, the cabin pressurization controller may have failed and allowed the outfl ow to close. Open the manual control valve slightly, select 

MANUAL position on the cabin pressure selector, and regulate pressure manually. If manual control
EMERGENCY PROCEDURES 3-13

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

HIGH PRESSURE MALFUNCTION (continued)

is ineffective, the safety valve should relieve excess cabin pressure at 7.25 psi. Prior to landing, the 

cabin pressure differential must be eliminated by use of the manual control or the following alternate 

procedure:

 1. Altitude ................................................................................................... BELOW 12,000 FEET

 2. Bleed Air Switches ............................................................................................................. OFF

 3. Allow cabin to depressurize to less than 1 psi differential.

 4. Cabin Dump Switch ........................................................................................................DUMP

NOTE

If cabin pressure is dumped when a signifi cant cabin pressure differential exists, the resulting sensation may be alarming and uncomfortable to passengers. Consequently, use of the dump valve should 

normally be restricted to situations where cabin pressure differential 

is less than 1 psi or when other methods of pressure differential 

control are ineffective.

 5. Bleed Air Switches ............................................................................................................... ON

 6. Proceed unpressurized to airport. Air conditioning will be available.

EXCESSIVE RATE OF PRESSURIZATION

If an excessive rate of pressurization is experienced and it cannot be controlled by the rate knob 

on the cabin pressurization controller or by the manual control knob, the following steps should be 

accomplished:

 1. Bleed Air Switches ............................................................................................................. OFF

 If step 1 eliminates the excessive rate of pressurization, determine the source of the 

malfunction by turning the bleed air controls on individually. If the malfunction was caused 

by one of the bleed air control valves, leave the malfunctioning side off and continue 

pressurized fl ight using bleed air from one engine.

 If the pressure surge does not decrease:

 2. Cabin Dump Switch ........................................................................................................DUMP

NOTE

If cabin pressure is dumped when a signifi cant cabin pressure differential exists, the resulting sensation may be alarming and uncomfortable to passengers. Consequently, use of the dump valve should 

normally be restricted to situations where cabin pressure differential 

is less than 1 psi or when other methods of pressure differential 

control are ineffective.
Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

3-14 EMERGENCY PROCEDURES

MERLIN III B

EMERGENCY DESCENT PROCEDURES

If the cabin pressure is lost for any reason while at high altitude, execute the following procedure:

1. OXYGEN VALVE ................................................................................................................. ON

 2. PASSENGER AND CREW OXYGEN MASKS .................................................................DON

 3. Speed Levers ....................................................................................................................HIGH

 4. Power Levers .......................................................................................................FLIGHT IDLE

 5. Airspeed ...............................................................................173 KIAS (176 KCAS) MAXIMUM

 6. Landing Gear ................................................................................................................. DOWN

 7. Flaps ....................................................................................................................... ONE-HALF

 8. Altitude ..............................................................................................................AS REQUIRED

CABIN DOOR WARNING LIGHT ON

PRIOR TO TAKEOFF

 Takeoff should not be initiated.

IN FLIGHT

 1. Depressurize airplane.

 2. Descend as required.

 3. Land as soon as practicable.

HYDRAULIC SYSTEM FAILURE

An emergency hand pump and a cable operated manual release system are provided to extend 

the landing gear in the event of a hydraulic system failure. A stand pipe system in the hydraulic reservoir provides a supply of fl uid for hand pump operation. The manual release system also permits free 

fall gear extension in the event that all hydraulic fl uid is lost.

There are no emergency provisions to extend or retract the fl aps. Landing approach should be 

made at 1.3 VS1 for the existing airplane confi guration. (For fl aps up confi guration, use 131 KIAS 

(134 KCAS) at 12,500 pounds gross weight and 6 KIAS less airspeed for each 1,000 pounds less 

gross weight.)

WARNING

IN THE EVENT OF A HYDRAULIC SYSTEM MALFUNCTION, THE NOSE WHEEL STEERING SYSTEM MUST NOT 

BE ARMED. STEER WITH BRAKES, POWER AND RUDDER.
EMERGENCY PROCEDURES 3-15

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

LANDING GEAR EMERGENCY EXTENSION

 1. Airspeed ................................................................................173 KIAS (176 KCAS) MAXIMUM

 2. Landing Gear Handle ...................................................................................................... DOWN

 3. Emergency Release Lever ....................................................................................ROTATE AFT

 4. Hand Pump Valve Handle ......................................... PULL PIP PIN/ROTATE VALVE HANDLE

90 DEGREES FORWARD

 5. Emergency Hand Pump ..........................................................................PUMP AS REQUIRED

 a. Gear indicator .............................................................................ALL DOWN AND LOCKED

 b. Hydraulic pressure gauge .................................................................... 500 PSI TO 800 PSI

NOTE

• If manual extension is used because of a failure in the landing gear 

electrical control system, the hydraulic pressure gauge will 

 continue to indicate approximately 2,000 psi system pressure. In 

 this case, the pressure to the gear down actuators can be detected 

only by the effort required to move the emergency hand pump.

• If a failure at the bottom of the hydraulic pack allows depletion of all hydraulic fl uid, the emergency hand pump will not 

provide pressure. Nevertheless, Step 3 above will allow the 

landing gear to free fall to a safe, down, and locked position.

• Hydraulic pressure to the hydraulic nose wheel steering system 

will not be available following landing gear emergency extension 

required by either hydraulic failures or gear position selector 

valve electrical failures. Do not arm nose wheel steering.

GEAR UP LANDINGS

NOTE

• If either main gear will not extend, land with all three gear up if 

possible. If the nose gear will not extend, land on the mains. 

• Ensure that passengers are thoroughly briefed as to bracing position and evacuation procedure.

• Consider removal and secure stowage of escape hatches prior to 

landing. Expect the entrance door to operate normally. It will not 

open fully after landings with the nose or left gear retracted.

• Histrically, airplanes of this class have received more airframe 

damage from gear up landings on sod than from landins on smooth 

paved surfaces.
Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

3-16 EMERGENCY PROCEDURES

MERLIN III B

GEAR UP LANDINGS (continued)

• Propeller blades contacting the surface while turning under power 

tend to disintegrate and throw shrapnel which may puncture the 

fuselage. Blades contacting the surface when feathered, or nearly 

feathered, will bend slightly and wear away but most likely will not 

shatter and will aid in holding the wings and nacelles off the runway.

Landing with All Three Gear up:

 1. Use full fl aps.

 2. Approach runway at 1.3 VS plus 5 to 10 KIAS.

 3. Do not feather propellers until landing on the runway is assured. Drag will be reduced and 

gliding distance increased after propellers are feathered.

 4. Shut off electrical power just prior to touchdown (this is to allow use of the pitch trim system 

until touchdown). Leave batteries on during night landings to permit use of landing lights.

5. Allow aircraft to touch down in arelatively fl at attitude and on the center line. Use rudder for 

directional control.

Landing with Nose Gear up:

 1. Use normal approach technique and fl ap confi guration.

 2. Feather propellers and shut off electrical power after mains have touched the runway. Leave 

batteries on during night landings to permit use of landing lights.

 3. Hold nose of the aircraft off the runway as long as practical, but not so long that pitch control 

is lost. Put nose on runway gently rather than letting it drop to the runway.

Landing with Nose and One Main Extended:

 1. Attempt to retract all three gear. Check the position of the emergency gear release lever, the 

hand pump valve handle, and the landing gear control circuit breaker. Transfer the landing 

gear control to the other essential bus using the transfer switch.

 2. If possible, select the runway with the fewest obstuctions and fl attest terrain on the side of the 

unextended gear. 

 3. Feather propellers after landing on the runway is assured. Drag will be reduced and gliding 

distance increased after propellers are feathered.

 4. Shut off electrical power just prior to touchdown (this is to allow use of the pitch trim system 

until touchdown). Leave batteries on during night landings to permit use of landing lights.
EMERGENCY PROCEDURES 3-17

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

GEAR UP LANDINGS (continued)

5. Hold the wing with the unextended landing gear off the runway as long as possible. Use brakes 

and rudder for aircraft directional control. Expect the aircraft to turn into the low wing.

STABILIZER TRIM MALFUNCTIONS

STABILIZER TRIM SYSTEM RUNAWAY

The application of electrical power to the stabilizer trim actuators is indicated by an aural signal. 

If the signal occurs in fl ight when the trim system is not being operated, the following procedure 

should be initiated immediately:

1. ELEVATOR CONTROL ........................OVERPOWER TO MAINTAIN AIRPLANE CONTROL

 2. TRIM SELECTOR ...........................................................................OFF (CENTER POSITION)

STABILIZER TRIM SYSTEM RUNAWAY (continued)

3. Trim Selector .......................................................................OPPOSITE POSITION FROM WHERE

 MALFUNCTION OCCURRED

 4. Retrim as required.

PILOT'S TRIM SYSTEM INOPERATIVE

 1. Trim Selector ...............................................................................................................COPILOT

 2. Pilot's Auxiliary Trim Switch, or

 Copilot's Trim Switches ............................................................................ TRIM AS REQUIRED

COPILOT'S TRIM SYSTEM INOPERATIVE

 1. Trim Selector .................................................................................................................... PILOT

 2. Pilot's Trim Switches ................................................................................ TRIM AS REQUIRED

BOTH PILOT'S AND COPILOT'S TRIM SYSTEM INOPERATIVE

 1. Trim Selector ................................................................................................ OFF (CENTERED)

 2. Airspeed ........................................ AS REQUIRED TO MAINTAIN LOW ELEVATOR FORCES

 3. SAS2 Clutch Switch ...........................................................................................AS REQUIRED

NOTE

• Turning the SAS2 clutch switch OFF will reduce required 

pull forces by approximately 20 pounds at approach speeds.

• If the trim system fails in an extreme nose down trim position, do not extend fl aps unless required for landing because 
Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

3-18 EMERGENCY PROCEDURES

MERLIN III B

STABILIZER TRIM MALFUNCTIONS (continued)

BOTH PILOT'S AND COPILOT'S TRIM SYSTEM INOPERATIVE (continued)

 of the subsequent high pull force required to maintain level 

fl ight.

• If the trim system fails in an extreme nose up trim position, 

fl ap extension (below VFE ) will reduce the push force required to maintain level fl ight.

 4. Flaps (on landing approach) ..............................................................................AS REQUIRED

NOTE

Flap extension decreases push force requirements.

 5. Landing Gear ..................................................................................... DOWN WHEN DESIRED

NOTE

Gear extension increases push force requirements slightly.

GO-AROUND WITH STABILIZER TRIM INOPERATIVE

WARNING

VERY HIGH PUSH FORCES WILL BE REQUIRED IF THE 

FLAPS ARE RETRACTED WITH THE STABILIZER TRIM IN THE 

EXTREME NOSE UP POSITION. IF A GO-AROUND OR BALKED 

LANDING IS REQUIRED WHEN THE STABILIZER TRIM IS STUCK 

IN AN EXTREME NOSE UP POSITION, DO NOT RETRACT THE 

FLAPS IMMEDIATELY.

 1. Power .................................................................................................................AS REQUIRED

NOTE

Application of power increases push force requirements.

 2. Flaps ............................................................................................ RETRACT IN INCREMENTS
EMERGENCY PROCEDURES 3-19

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

GO-AROUND WITH STABILIZER TRIM INOPERATIVE (continued)

NOTE

Flap retraction increases push force requirements.

 3. Airspeed ................................................ AS REQUIRED TO MAINTAIN LOW STICK FORCES

 4. Landing Gear .............................................................................. RETRACT WHEN FEASIBLE

STABILITY AUGMENTATION AND STALL AVOIDANCE

SYSTEM (SAS2 ) MALFUNCTIONS

SAS2 CLUTCH SWITCH .............................................................................................................. OFF

CAUTION

WITH THE SAS2 DISENGAGED (OR INOPERATIVE) THE AIRPLANE WILL HAVE UNDESIRABLE STALL CHARAC-TERISTICS 

AT AFT CENTER OF GRAVITY LOADINGS. ADEQUATE MARGINS ABOVE THE STALL SPEED SHOULD BE MAINTAINED 

IN ALL OPERATIONS. ENSURE THAT TOUCHDOWN SPEED IS 

EQUAL TO OR GREATER THAN 1.1 V S1.

NOTE

• With SAS2 disengaged or inoperative, there will be no augmented 

stick forces. Very light elevator forces will be required to maneuver 

the airplane at airspeeds below approximately 135 KIAS, particularly when operating at aft c.g. loadings. Airspeed should be 

monitored closely.

• Fault light on fl ashing indicates a stopped servo or servo 

clutch disengagement.

• Fault light on steady in flight indicates computer power 

failure, or computer power failure with simultaneous servo, 

or clutch failure.

• With the fault light on, angle of attack and stall warning indications 

may be unreliable.
Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

3-20 EMERGENCY PROCEDURES

MERLIN III B

Issued: January 14, 1982

Revised: November 14, 2014 

SAS2 MALFUNCTION – NOSE DOWN

In the event of a nose down malfunction (no aural tone is heard) the following procedure should 

be initiated:

 1. ELEVATOR CONTROL ........................OVERPOWER TO MAINTAIN AIRPLANE CONTROL

 2. SAS2 CLUTCH SWITCH .................................................................................................... OFF

 3. SAS2 Circuit Breakers .......................................................................................................PULL

CAUTION

WITH THE SAS2 DISENGAGED THE AIRPLANE WILL HAVE 

UNDESIRABLE STALL CHARACTERISTICS AT AFT CENTER OF 

GRAVITY LOADINGS. ADEQUATE MARGINS ABOVE THE STALL 

SPEED SHOULD BE MAINTAINED IN ALL OPERATIONS. ENSURE THAT TOUCHDOWN SPEED IS EQUAL TO OR GREATER 

THAN 1.1 V S1.

NOTE

With the SAS2 inoperative, there will be no augmented stick 

forces. Very light elevator forces will be required to maneuver the airplane at airspeeds below approximately 135 KIAS, particularly when 

operating at aft c.g. loadings. Airspeed should be monitored closely.

AURAL STALL WARNING AT SPEEDS WELL IN EXCESS OF NORMAL STALL WARNING SPEEDS

When an aural stall warning occurs in unaccelerated fl ight at speeds well in excess of normal stall 

warning speed, possible damage to the angle of attack vane is indicated and an inadvertent nose 

down push may occur.

1. SAS 2 CLUTCH SWITCH ................................................................................................... OFF

To silence the stall warning horn;

 2. Stall Warning Circuit Breaker .............................................................................................PULL

CAUTION

WITH THE SAS2 DISENGAGED THE AIRPLANE WILL HAVE 

UNDESIRABLE STALL CHARACTERISTICS AT AFT CENTER OF 

GRAVITY LOADINGS. ADEQUATE MARGINS ABOVE THE STALL 

SPEED SHOULD BE MAINTAINED IN ALL OPERATIONS. ENSURE THAT TOUCHDOWN SPEED IS EQUAL TO OR GREATER 

THAN 1.1 V S1.
EMERGENCY PROCEDURES 3-21

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

AURAL STALL WARNING AT SPEEDS WELL IN EXCESS OF NORMAL STALL WARNING 

SPEEDS (continued)

NOTE

With the SAS2 inoperative, there will be no augmented stick forces. 

Very light elevator forces will be required to maneuver the airplane 

at airspeeds below approximately 135 KIAS, particularly when operating at aft c.g. loadings. Airspeed should be monitored closely.

YAW DAMPER/RUDDER BIAS MALFUNCTIONS

POWER FAILURE

The yaw damper warning light, located on the annunciator panel, illuminates when a power 

failure occurs. If such a failure occurs, the yaw damper and rudder bias switches should be turned 

OFF and care should be taken to avoid extreme skidding or slipping turns.

NOTE

Maximum allowable 90 degrees crosswind component for landing 

with yaw damper inoperative is 10 knots.

ELECTRICAL SERVO RUNAWAY

A runaway can occur when an erroneous electrical signal is transmitted to the yaw damper/rudder 

bias servo primary electrical clutch; however, the system is provided with a secondary mechanical 

clutch that prevents excessive rudder forces being generated. Approximately 65 pounds of rudder 

force is required to overcome maximum servo output. If a runaway occurs:

 1. Rudder Pedals ................................................. AS REQUIRED FOR COORDINATED FLIGHT

 2. Yaw Damper Switch ............................................................................................................ OFF

 3. Avoid extreme skidding or slipping turns.

EMERGENCY EXIT

There is one emergency exit on the right side of the center cabin. The hatch is of the plug type and 

opens into the cabin. To open the emergency exit:

 1. Cabin ...............................................................................................................DEPRESSURIZE

 2. Hatch Release Handles .....................................................................PULL INBOARD AND UP

NOTE

Pull hatch inward, rotate, extend through opening, and discard outside the airplane. Ensure that the hatch is clear of the 

exit route of the airplane.

 Issued: November 14, 2014
Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

3-22 EMERGENCY PROCEDURES

MERLIN III B

NOSE WHEEL STEERING MALFUNCTION

Fault protection is provided by circuitry which automatically deactivates the nose wheel steering 

system if an electrical malfunction occurs. The nose wheel is then free to caster and rudder, differential braking, and/or differential power can be used for steering.

If the system fails to test correctly, the arm switch should be placed in the OFF position and 

steering accomplished with rudder, differential braking, and/or differential power.

 1. Flashing NOSE STEERING Light

a. NWS power lever button ....................................................................................RELEASE

 b. Directional control..................................................... MAINTAIN WITH RUDDER, BRAKES

AND/OR POWER

 c. Nose wheel steering arm switch.................................................................................... OFF

 d. Nose wheel steering circuit breaker .............................................................................PULL

 2. Unwanted Steering Defl ection

a. NWS power lever button ....................................................................................RELEASE

 b. Directional control..................................................... MAINTAIN WITH RUDDER, BRAKES

AND/OR POWER

 c. Nose wheel steering arm switch.................................................................................... OFF

 d. Nose wheel steering circuit breaker .............................................................................PULL

 3. Park Light Illuminated When Park Button is Not Depressed:

a. NWS power lever button ....................................................................................RELEASE

 b. Directional control..................................................... MAINTAIN WITH RUDDER, BRAKES

AND/OR POWER

 c. Nose wheel steering arm switch.................................................................................... OFF

 d. Nose wheel steering circuit breaker .............................................................................PULL

NOTE

It is normal for the park light to remain illuminated, but vary in intensity, 

during 4 to 7 second transition time form park mode to normal mode.

On those aircraft which have been modifi ed in accordance with Fairchild Swearingen Service Bulletin 

32-037.

NOSE WHEEL STEERING ELECTRICAL MALFUNCTION

Fault protection is provided by circuitry which automatically deactivates the nose wheel steering 

system if an electrical malfunction occurs. The nose wheel is then free to caster and rudder, differential braking, and/or differential power can be used for steering.

If the system fails to test correctly, the arm switch should be placed in the OFF position and 

steering accomplished with rudder, differential braking, and/or differential power.

 Issued: November 14, 2014
EMERGENCY PROCEDURES 3-23

MERLIN III B

Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

NOSE WHEEL STEERING ELECTRICAL MALFUNCTION (continued)

In the event of a fl ashing NOSE STEERING light, an unwanted steering defl ection, and/or park 

light illuminated when the PARK button is not depressed:

 1. NWS Power Lever Button ..........................................................................................RELEASE

 2. Right Speed Lever ................................................APPROXIMATELY 1/2 INCH FWD OF LOW

 3. Directional Control ............................ MAINTAIN WITH RUDDER, BRAKES, AND/OR POWER

 4. Nose Wheel Steering Arm Switch ....................................................................................... OFF

 5. Nose Wheel Steering Circuit Breaker ................................................................................PULL

NOTE

It is normal for the park light to remain illuminated, but vary in intensity, 

during 4 to 7 second transition time form park mode to normal mode.

NOSE WHEEL STEERING HYDRAULIC MALFUNCTION

An illuminated NOSE STEER FAIL amber annunciator light indicates that hydraulic pressure is being supplied to the nose wheel steering actuator but the pilot is not commanding a steering signal. 

Illumin-ation of the NOSE STEER FAIL light should alert the pilot to potentially undesirable steering 

actua- tion and that corrective action may be required. Corrective action depends upon the 

operational phase.

NOSE STEER FAIL Light on –

 (During ground operations):

 1. NWS Power Lever Button ...........................................................................PRESS AND HOLD

or:

 2. Right Speed Lever ............................................................................................................. LOW

 3. NOSE STEER FAIL Light ...................................................................................... CHECK OUT

 4. Directional Control .................................................................................. MAINTAIN WITH NWS

 5. Do Not Take Off.

 (During Initial part of takeoff roll):

 1. NWS Power Lever Button ...........................................................................PRESS AND HOLD

 2. NOSE STEER FAIL Light ...................................................................................... CHECK OUT

 3. Directional Control ......................................................................................................MAINTAIN

 4. Takeoff ............................................................................................................................ ABORT

 (During fi nal part of takeoff roll):

 1. NWS Power Lever Button ...........................................................................PRESS AND HOLD

 2. NOSE STEER FAIL Light ...................................................................................... CHECK OUT

 3. Directional Control ......................................................................................................MAINTAIN

 Continue with Normal Takeoff Procedures.

 Issued: November 14, 2014
Issued: November 3, 1978

Reissued: November 2, 1979

Revised: November 14, 2014

3-24 EMERGENCY PROCEDURES

MERLIN III B

NOSE WHEEL STEERING HYDRAULIC MALFUNCTION (continued)

 (In fl ight with gear down):

 1. NWS Power Lever Button ...........................................................................PRESS AND HOLD

 2. NOSE STEER FAIL Light ...................................................................................... CHECK OUT

NOTE

Conduct normal landing and rollout while keeping the power lever 

button depressed to avoid uncommanded steering actuation.

 Issued: November 14, 2014