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9 JANUARY 1981TEMPORARY REVISION 23 NOV 93

CANCELED 14 NOVEMBER 2007

COPYRIGHT NOTICE

COPYRIGHT 2006

BELL HELICOPTER TEXTRON INC.

AND BELL HELICOPTER TEXTRON

CANADA LTD.

ALL R IGHTS RESERVED

CANC

ELED

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APPROVED DATE

NOTICE

This Temporary Revision is canceled. Remove and discard from Flight Manual the temporary

pages dated 23 November 1993, including these canceled pages.

BHT-412-FM-1

Temporary Revision 23 NOV 1993

BCanceled 14 NOV 2007

LOG OF FAA APPROVED REVISIONS

Temporary .................0 ..................... 23 NOV 93 Canceled.................... .......................14 NOV 07

MANAGER

ROTORCRAFT CERTIFICATION OFFICE

FEDERAL AVIATION ADMINISTRATION

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9 JANUARY 1981TEMPORARY REVISION 16 AUGUST 1996


COPYRIGHT NOTICE

COPYRIGHT 2007


AND BE LL HELICOPTE R TEXTRON

CANADA LTD.

ALL RIGHTS RE SERVE D

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APPROVED DATE

NOTICE


pages dated 16 August 1996, including these canceled pages.

BHT-412-FM-1

Temporary Revision 16 AUG 1996



Temporary .................0 ..................... 16 AUG 96 Canceled.................... .......................14 NOV 07

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9 JANUARY 1981TEMPORARY REVISION 21 APRIL 1998


COPYRIGHT NOTICE

COPYRIGHT 2007


AND BELL HEL ICOPTE R TEXTRON

CANADA LTD.

ALL RIGHTS RESERVED

CANC

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APPROVED DATE

NOTICE


pages dated 21 April 1998, including these canceled pages.

BHT-412-FM-1

Temporary Revision 21 APR 1998



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9 JANUARY 1981TEMPORARY REVISION 12 MAY 1999


COPYRIGHT NOTICE

COPYRIGHT 2007


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ALL RIGHTS RE SERVED

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NOTICE


pages dated 12 May 1999, including these canceled pages.

BHT-412-FM-1

Temporary Revision 12 May 1999



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Please insert attached BHT-412-FM-1 Revision 22, dated 31 October 2007 intoFlight Manual in accordance with Log of Pages.

Note: Section 3 has no change bars since it has been revised in its entirety.

9 JANUARY 1981

REVISION 22 31 OCTOBER 2007

BHT-412-FM-1

NOTICE

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ROTORCRAFT

FLIGHT MANUAL

S/N 33001 33107

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9 JANUARY 1981REVISION 22 31 OCTOBER 2007

ROTORCRAFT

FLIGHT MANUAL

THIS MANUAL SHALL BE IN THE HELICOPTER DURING ALL OPERATIONS

COPYRIGHT NOTICE

COPYRIGHT 2007


AND BELL HELICOPTER TEX TRON

CANADA LTD.

ALL RIG HTS RESERVE D

S/N 33001 33107

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NOTICE PAGE

Additional copies of this publication may be obtained by contacting:

Commercial Publication Distribution Center

Bell Helicopter Textron Inc.

P. O. Box 482

Fort Worth, Texas 76101-0482

NPRev. 2231 OCT 2007

BHT-412-FM-1

These data are proprietary to Bell Helicopter Textron Inc. Disclosure,

reproduction, or use of these data for any purpose other than helicopter

operation is forbidden without prior written authorization from Bell

Helicopter Textron Inc.

PROPRIETARY RIGHTS NOTICE

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31 OCT 2007Rev. 22A

BHT-412-FM-1

LOG OF PAGES

REVISION REVISIONNO. NO.PAGE PAGE

NOTE

Revised text is indicated by a black vertical line. Insert latest revision pages; dispose of

superseded pages.

Original ......................0 ......................09 JAN 81

Revision.....................1 ......................13 FEB 81

Revision.....................2 .....................20 MAR 81

Revision.....................3 ......................08 JUN 98Revision.....................4 ..................... 21 DEC 81

Revision.....................5 ......................15 JUN 83

Revision.....................6 ......................08 SEP 83

Revision.....................7 ..................... 10 APR 84

Revision.....................8 ..................... 26 OCT 84

Revision.....................9 ......................04 FEB 85

Revision....................10 .....................14 FEB 86

Revision....................11 .....................05 JAN 90

Revision ................... 12.....................20 DEC 90

Revision ................... 13..................... 10 SEP 92

Revision ................... 14.................... 14 MAY 93

Revision ................... 15..................... 24 FEB 97Revision ................... 16.................... 25 AUG 97

Revision ................... 17..................... 14 SEP 97

Revision ................... 18.................... 26 MAR 98

Revision ................... 19.....................21 APR 98

Revision ................... 20.....................18 DEC 98

Revision ................... 21.....................05 NOV 02

Revision ................... 22.....................31 OCT 07

Cover..........................................................22

Title ............................................................22

NP...............................................................22

A B...........................................................22

C/D..............................................................22

i ii.............................................................22

iii/iv.............................................................22

1-1 1-2 .....................................................221-3...............................................................18

1-4...............................................................22

1-5.................................................................6

1-6...............................................................22

1-7.................................................................6

1-8...............................................................16

1-8A............................................................22

1-8B............................................................16

1-9...............................................................22

1-10...............................................................6

1-11 1-14 .................................................22

1-14A/1-14B ...............................................221-15.............................................................22

1-16.............................................................16

1-17 1-18................................................... 6

1-19/1-20.................................................... 15

2-1 2-2..................................................... 22

2-3 .............................................................. 10

2-4 ................................................................ 6

2-5 2-6..................................................... 20

2-7 2-8..................................................... 22

2-8A/2-8B................................................... 222-9 .............................................................. 11

2-10 2-11................................................. 18

2-12 2-13................................................. 17

2-14............................................................ 11

2-15............................................................ 18

2-16............................................................ 11

2-17............................................................ 19

2-18 2-20................................................. 22

3-1 3-26................................................... 22

4-1/4-2........................................................ 20

4-3 ................................................................ 6

4-4 .............................................................. 114-5 4-6..................................................... 16

4-6A 4-6B................................................ 16

LOG OF REVISIONS

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LOG OF PAGES (CONT)

REVISION REVISIONNO. NO.PAGE PAGE

4-7 4-18......................................................64-19/4-20.......................................................6

4-21 4-23....................................................6

4-24 4-30..................................................20

4-31 4-60 (Deleted)................................. 205-1/5-2 ........................................................ 22

5-3 5-8 ..................................................... 22

6-1 6-38 ................................................... 10

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APPROVED DATE

31 OCT 2007Rev. 22C/D

BHT-412-FM-1

Original ..................... 0...................... 09 JAN 81

Revision .................... 1...................... 13 FEB 81

Revision .................... 2..................... 20 MAR 81

Revision .................... 3...................... 08 JUN 98Revision .................... 4......................21 DEC 81

Revision .................... 5...................... 15 JUN 83

Revision .................... 6...................... 08 SEP 83

Revision .................... 7......................10 APR 84

Revision .................... 8......................26 OCT 84

Revision .................... 9...................... 04 FEB 85

Revision ................... 10..................... 14 FEB 86

Revision ................... 11..................... 05 JAN 90

Revision ...................12 .................... 20 DEC 90

Revision ...................13 .....................10 SEP 92

Revision ...................14 .................... 14 MAY 93

Revision ...................15 .....................24 FEB 97Revision ...................16 .................... 25 AUG 97

Revision ...................17 .....................14 SEP 97

Revision ...................18 ....................26 MAR 98

Revision ...................19 .................... 21 APR 98

Revision ...................20 .................... 18 DEC 98

Revision ...................21 .................... 05 NOV 02

Revision ...................22 .................... 31 OCT 07


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GENERAL INFORMATION

31 OCT 2007Rev. 22

ORGANIZATION

The Rotorcraft Flight Manual is divided into

six sections as follows:

Sect ions 1 through 4 contain the FAA

approved data necessary to operate the basic

helicopter in a safe and efficient manner.

Section 5 contains the listing of approved

Supplements for optional equipment which

shall be used in conjunction with the basic

Flight Manual when the respective optional

equipment kits are installed.

Section 6 contains limitations, procedures,

and performance data for Category A

Operations.

The Manufacturer's Data manual (BHT-412-

MD-1) contains additional information to be

used in conjunction with the Flight Manual.

TERMINOLOGY

WARNINGS, CAUTIONS, AND NOTES

Warnings, cautions, and notes are used

throughout th is manual to emphasize

important and critical instructions as follows:

WARNING

AN OPERATING PROCEDURE,

PRACTICE, ETC., WHICH, IF NOT

CORRECTLY FOLLOWED, COULD

RESULT IN PERSONAL INJURY OR

LOSS OF LIFE.

CAUTION

AN OPERATING PROCEDURE,

PRACTICE, ETC., WHICH, IF NOT

STRICTLY OBSERVED, COULD

RESULT IN DAMAGE TO OR

DESTRUCTION OF EQUIPMENT.

NOTE

An operating procedure, condition,

etc., which is essential to highlight.

USE OF PROCEDURAL WORDS

The concept of procedural word usage and

intended meaning which has been adhered to

in preparing this manual is as follows:

SHALL has been used only when the

application of a procedure is mandatory.

SHOULD has been used only when the

application of a procedure is recommended.

MAY and NEED NOT have been used only

when the application of a procedure is

optional.

Section 1 LIMITATIONS

Section 2 NORMAL PROCEDURES

Section 3 EMERGENCY/

MALFUNCTION

PROCEDURES

Section 4 PERFORMANCE

Section 5 OPTIONAL EQUIPMENT

SUPPLEMENTS

Section 6 CATEGORY A

OPERATIONS

Section 1 WEIGHT AND BALANCE

Section 2 SYSTEMS DESCRIPTIONSection 3 OPERATIONAL

INFORMATION

Section 4 HANDLING/SERVICING/

MAINTENANCE

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iiRev. 2231 OCT 2007

ABBREVIATIONS

Abbreviations used throughout this manual

are defined as follows:

AC Alternating CurrentADD Air Data Display

ADF Automatic Direction Finder

ADI Attitude Director Indicator

AFCS Automatic Flight Control

System

AHRS Attitude Heading and

Reference System

ALTN Alternate

AOG Aircraft on Ground

API Actuator Position Indicator

AP 1 / AP 2 Autopilot 1/Autopilot 2

ATT or ATTD Attitude

AUX Auxiliary

BAT Battery

BLWR Blower

C Celsius

CDI Course Deviation Indicator

CCP Compass Control Panel

CG Center of Gravity

CPL Couple

CPLT Copilot

CRS Course

CYC CTR Cyclic Center

DC Direct Current

DCPL Decouple

DECEL Deceleration

DECR Decrease

DEG Degree(s)

DET Detector

DH Decision Height

EEPROM Electrically Erasable

Programmable Read Only

Memory

EMERG Emergency

ENC Encoding

F Fahrenheit

FT Force Trim or Foot/Feet

FUEL

TRANS

Fuel Transfer

GEN Generator

GOV Governor

HD Density Altitude

HDG Heading

HP Pressure Altitude

HP 1 / HP 2 Helipilot 1/Helipilot 2

HSI Horizontal Situation

Indicator

HYDR Hydraulic

IAS Indicated Airspeed

ICS Intercommunication

System

IFR Instrument Flight RulesIGE In Ground Effect

IMC Instrument Meteorological

Conditions

INCR Increase

INTCON Interconnect

INV Inverter

ITT Interturbine Temperature

IVSI Instantaneous Vertical

Situation Indicator

KCAS Knots Calibrated Airspeed

KIAS Knots Indicated Airspeed

LE Level

LF Low Frequency

LH Left Hand

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LRC Long Range Cruise

LT Light(s)

MAG Magnetic

MAX END Maximum Endurance

MCP Maximum ContinuousPower

NI Gas Producer RPM

NII Power Turbine RPM

NAV Navigation

NON-ESNTL Non-essential

NORM Normal

NR Rotor RPM

OAT Outside Air Temperature

OEI One Engine Inoperative

OGE Out of Ground Effect

OVRD Override

PART SEP Particle Separator

PNL Panel

PSI Pounds per Square Inch

PWR Power

RAD ALT Radar Altimeter

REL Release

RH Right Hand

SAS Stability Augmentation

System

SBY ATT Standby Attitude

SL Sea Level

STBY Standby

SYNC SynchronizeSYS System

VAC Volts Alternating Current

VDC Volts Direct Current

VEL HLD Velocity Hold

VFR Visual Flight Rules

VG Vertical Gyro

VLF Very Low Frequency

VMC Visual Meteorological

Conditions

VNE Never Exceed Speed

VTOCS Takeoff Climbout Speed

XPDR Transponder

XFEED Crossfeed

XMSN Transmission

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31 OCT 2007Rev. 221-1

Section 1LIMITATIONS

1

TABLE OF CONTENTS

Page

Subject Number

Operating Limitations..................................................................................................... 1-3

Basis of Certification...................................................................................................... 1-3

Type of Operation ........................................................................................................... 1-3

Required Equipment....................................................................................................... 1-3

AFCS Limitations........................................................................................................ 1-3

Required Equipment IFR ....................................................................................... 1-3

Optional Equipment........................................................................................................ 1-4

Flight Crew Limitations.................................................................................................. 1-4

Internal Cargo Operation............................................................................................ 1-4

Doors Open or Removed................................................................................................ 1-4

Weight/CG Limitations ................................................................................................... 1-4

Weight Limits .............................................................................................................. 1-4

Longitudinal Center of Gravity Limits....................................................................... 1-4

Lateral Center of Gravity Limits ................................................................................ 1-4

Loading limitations ......................................................................................................... 1-6

Passenger Loading..................................................................................................... 1-6

Internal Cargo Loading............................................................................................... 1-6Airspeed Limitations ...................................................................................................... 1-6

Climb/Descent Limitations............................................................................................. 1-9

Altitude Limitations ........................................................................................................ 1-9

Ambient Air Temperature Limitations........................................................................... 1-9

Height-Velocity Limitations............................................................................................ 1-9

Maneuvering Limitations................................................................................................ 1-9

Slope Landing Limitations............................................................................................. 1-9

Electrical Limitations...................................................................................................... 1-11

Battery Limitations ..................................................................................................... 1-11

Generator Limitations................................................................................................. 1-11

Engine Starter Limitations ......................................................................................... 1-11

Ground Power Starts.................................................................................................. 1-11Power Plant Limitations ................................................................................................. 1-11

Gas Producer RPM (NI) Limits ................................................................................... 1-11

Power Turbine RPM (NII) Limits................................................................................. 1-12

Interturbine Temperature (ITT) Limits....................................................................... 1-12

Fuel Pressure Limits................................................................................................... 1-12

Oil Pressure Limits ..................................................................................................... 1-12

Oil Temperature Limits............................................................................................... 1-13
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TABLE OF CONTENTS (CONT)

Page

Subject Number

Engine Restart Limits................................................................................................. 1-13

Engine Torque Limits................................................................................................. 1-13Transmission Limitations.............................................................................................. 1-13

Transmission Torque Limits...................................................................................... 1-13

Transmission Oil Pressure Limits............................................................................. 1-13

Transmission Oil Temperature Limits ...................................................................... 1-13

Rotor Limitations............................................................................................................ 1-13

Rotor RPM (NR) Limits Power ON......................................................................... 1-13

Rotor RPM (NR) Limits Power OFF ....................................................................... 1-13

Rotor RPM (NR) Limits Ground Operation ........................................................... 1-14

Rotor Brake Limitations................................................................................................. 1-14

Fuel and Oil Limitations................................................................................................. 1-14

Fuel .............................................................................................................................. 1-14

Engine and Combining Gearbox Oil ......................................................................... 1-14Transmission, Intermediate and Tail Rotor Gearbox Oil ........................................ 1-14

Hydraulic Limitations ..................................................................................................... 1-14

Hydraulic Pressure Limits ......................................................................................... 1-14A

Hydraulic Temperature Limits................................................................................... 1-14A

Instrument Markings and Placards............................................................................... 1-14A

Heater Operation............................................................................................................. 1-14A

Hoist Penalty Region...................................................................................................... 1-14A

LIST OF FIGURES

Figure Page

Subject Number Number

Weight-Altitude-Temperature Limitations Chart................................. 1-1........... 1-5

Gross Weight Center of Gravity Charts............................................... 1-2/1-2M.. 1-7

Placards and Decals.............................................................................. 1-3........... 1-8

Maximum Speed Sideward and Rearward, Crosswind and

Tailwind at a Hover................................................................................ 1-3A........ 1-8B

Height-Velocity Diagram (OEI).............................................................. 1-4........... 1-10

Instrument Markings ............................................................................. 1-5........... 1-15

Hoist CG Envelope ................................................................................ 1-6........... 1-19
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1-4Rev. 2231 OCT 2007

ATC transponder

Marker beacon receiver

Pilot instantaneous vertical speed

indicator (IVSI)

Force trim

Roof window blackout curtains

Emergency COMM panel, if installed,

(single pilot only)

OPTIONAL EQUIPMENT

Refer to appropr ia te F l ight Manual

Supplement(s) for additional limitations,

procedures, and performance data withoptional equipment installed.

FLIGHT CREW LIMITATIONS

The minimum crew consists of one pilot. The

right hand crew seat has been designated the

first pilot station.

INTERNAL CARGO OPERATION

NOTERefer to applicable operating rules

for internal cargo operations.

DOORS OPEN OR REMOVED

Helicopter may be flown with doors open or

removed only with Bell Standard Interior

(412-705-501) or Be l l De luxe Inter ior

(412-705-500) installed. Flight operation is

approved to the fo l lowing a l ternat ive

configurations during VFR conditions only:

Symmetrical configurations:

Both crew doors removed.

Both sliding doors locked open or

removed wi th both h inged panels

installed or removed.

Asymmetrical configurations:

Cargo doors can be opened or closed

asymmetrically to a locked position with

following restrictions:

1. Two-way communications betweenpilot and cabin crew member.

2. All crew members and passengers

are secured with an approved

restraint.

NOTE

Opening or removing doors shifts

helicopter center of gravity and

reduces VNE. Refer to Weight and

Balance section in Manufacturers

Data and to Airspeed Limitations.

WEIGHT/CG LIMITATIONS

WEIGHT LIMITS

Maximum gross weight for takeoff and

landing is 11,600 pounds (5262 kg).

Refer to Weight-Alt i tude-Temperature

Limitations chart (Figure 1-1) for maximum

allowable weight for takeoff, landing, and IGE

hover operation.

Minimum gross weight for flight is 6400

pounds (2903 kg).

Minimum combined crew weight at fuselage

station (FS 47.0) is 170 pounds (77.1 kg).

LONGITUDINAL CENTER OF GRAVITY

LIMITS

Longitudinal center of gravity limits vary from

station 130 to 144, depending on grossweight. Refer to Gross Weight Center of

Gravity Chart (Figure 1-2).

LATERAL CENTER OF GRAVITY LIMITS

Lateral center of gravity limits are 4.5 inches

(114.3 mm) left and right of fuselage centerline

for all gross weights.

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LOADING LIMITATIONS

NOTE

Refer to Weight and Balance section

of Manufacturers Data for loadingtables to be used in weight/CG

computations.

PASSENGER LOADING

The outboard facing seats should not be

occupied unless at least four of the forward or

aft facing passenger seats are occupied.

The above loading does not apply if cargo or

a combination of cargo and passengers are

being transported. It shall then be pilots

responsibility to ensure helicopter is properly

loaded so entire flight is conducted within the

limits of Gross Weight Center of Gravity

Charts (Figure 1-2).

INTERNAL CARGO LOADING

Maximum allowable deck loading for cargo is

100 pounds per square foot (4.9 kg/100 cm2

).Deck mounted cargo tie-down fittings are

provided and have an airframe structural

capacity of 1250 pounds (567.0 kg) vertical

and 500 pounds (226.8 kg) horizontal per

fitting. Provisions for installation of cargo

tie-down fittings are incorporated in the aft

cabin bulkhead and transmission support

structure and have an airframe structural

capacity of 1250 pounds (567.0 kg) at 90 to

the bulkhead and 500 pounds (226.8 kg) in

any direction parallel to the bulkhead. Cargoshall be secured by an approved restraint

method that will not impede access to the

cargo in the event of an emergency.

Maximum allowable baggage compartment

loading is 400 pounds (181 kg), not to exceed

100 pounds per square foot (4.9 kg/100 cm2).

AIRSPEED LIMITATIONS

NOTE

All indicated airspeed values in this

manual require instrument part

number 412-075-009-105 be installed.

Minimum IFR airspeed is 60 KIAS.

Basic VNEis 140 KIAS from sea level to 3000

feet HDat all gross weights. VNEdecreases for

ambient condit ions in accordance with

airspeed limitations placard (Figure 1-3).

Airspeed shall not exceed 105 KIAS (or

placarded VNE, if less) when operating above

maximum continuous transmission torque

(84%).

VNEwith only one helipilot engaged is 115

KIAS (or placarded VNE, if less). If both

helipilots are disengaged, basic VNEapplies.

VNEfor steady state autorotation is:

105 KIAS at or below 10,000 feet (3048 m)

HP;

80 KIAS above 10,000 feet (3048 m) HP.

VNE with doors symmetrical ly open or

removed is 100 KIAS.

VNEwith cargo doors opened asymmetrically

is 80 KIAS.

VNE with cargo doors in transit or in an

unlocked position is 60 KIAS.

NOTE

Asymmetric door configuration is

not au thor ized w i th energy

attenuating passenger seats.

VNE with doors symmetrical ly open or

removed is 60 KIAS with Bell Helicopter

installed energy attenuating passenger seats

(412-706-002).

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31 OCT 2007Rev. 221-8A

Figure 1-3. Placards and Decals (Sheet 2 of 2)

412-FM-1-0001

TWIN & 30 MIN OEI 100.8%

2 1/2 MIN OEI 102.4%

MAINTAIN 100% NRABOVE 6000FT HD

FOR GAS PRODUCER

INSTRUMENT PART NUMBER

212-075-037-101

TWIN & 30 MIN OEI 101.8%

2 1/2 MIN OEI 103.4%

FOR GAS PRODUCER

INSTRUMENT PART NUMBER

212-075-037-113

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31 OCT 2007Rev. 221-9

Maximum allowable airspeed for sideward or

rearward flight at or below 3000 feet HDis 35

knots . See F igure 1 -3A for addi t ion

limitations.

Maximum allowable tailwind or crosswind

speeds for hover operations at or below 3000feet HDis 35 knots. See Figure 1-3A for

additional limitations.

Refer to Critical Relative Wind Azimuths

diagram in Section 4.

CLIMB/DESCENT LIMITATIONS

Maximum IFR rate of climb or descent is 1000

feet per minute.

Maximum IFR approach slope is 5.

ALTITUDE LIMITATIONS

Maximum operating pressure altitude is

20,000 feet (6096 m).

Maximum density altitude for takeoff, landing,

and in-ground-effect maneuvers is 14,000 feet

(4267 m) . Refer to Weight -Al t i tude-

Temperature Limitations chart (Figure 1-1).

NOTE

Refer to applicable operating rules

for he ight a l t i tude oxygen

requirements.

AMBIENT AIR TEMPERATURELIMITATIONS

The maximum sea leve l ambient a i r

temperature for operation is 51.7C (125F)

and decreases with pressure altitude at the

standard lapse rate of 2C (3.6F)/1000 feet

(305 m) to 20,000 feet (6096 m).

The minimum ambient temperature for

operation at all altitudes is -40C (-40F).

HEIGHT-VELOCITY LIMITATIONS

The height-velocity limitations are critical in

the event of single engine failure during

takeoff, landing, or other operation near the

surface (Figure 1-4). The AVOID area of theHeight -Ve loc i ty d iagram def ines the

combinations of airspeed and height above

ground from which a safe single engine

landing on a smooth, level, firm surface

cannot be assured.

The Height-Velocity diagram is valid only

when the Weight-Alt itude-Temperature

limitations are not exceeded (Figure 1-1). The

diagram does not define the conditions which

assure continued flight following an engine

failure nor the conditions from which a safepower-off landing can be made.

MANEUVERING LIMITATIONS

Intentional maneuvering resulting in rol

attitudes in excess of 50 angle of bank, or

pitch attitudes lower than 15 nose down or

higher than 30 nose up are prohibited.

SLOPE LANDING LIMITATIONS

CAUTION

SLOPE LANDINGS HAVE BEEN

DEMONSTRATED TO THE SLOPE

LANDING L IMITS . OTHER

CONDITIONS INCLUDING, BUT NOT

LIMITED TO, WIND DIRECTION AND

VELOCITY, CENTER OF GRAVITY,

AND THE CONDIT ION OF THE

SLOPE (LOOSE ROCK, SOFT MUD,

SNOW, WET GRASS, ETC.) MAY

LIMIT MAXIMUM SLOPE TO A VALUE

LESS THAN THE PUBLISHED

LIMITS.

Slope landings are limited to 10 side slopes

4 nose up slope and 4 nose down slope.

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31 OCT 2007Rev. 221-11

ELECTRICAL LIMITATIONS

BATTERY LIMITATIONS

Maximum battery case temperature is 54.5C

(130F), as indicated by illumination of

BATTERY TEMP warning light.

WARNING

BATTERY SHALL NOT BE USED

FOR ENGINE START AFTER

ILLUMINATION OF BATTERY TEMP

LIGHT. BATTERY SHALL BE

REMOVED AND SERVICED

IN ACCORDANCE WITH

MANUFACTURERS INSTRUCTIONSPRIOR TO RETURN TO SERVICE.

Minimum ambient temperature for battery

start when battery and helicopter have been

cold soaked is -25C (-13F).

GENERATOR LIMITATIONS

NOTE

During OEI operation electrical loads

may have to be reduced to remain

below 150 amps.

NOTE

Ammeter needle may deflect fullsca le momentar i ly dur ing

generator-assisted start of second

engine.

ENGINE STARTER LIMITATIONS

Starter energizing times shall be limited as

follows:

30 seconds ON

60 seconds OFF

30 seconds ON

5 minutes OFF

30 seconds ON

15 minutes OFF

GROUND POWER STARTS

28 VDC ground power units for starting shal

be limited to 1000 amps maximum.

POWER PLANT LIMITATIONS

Pratt and Whitney Aircraft of Canada, Ltd

PT6T-3B.

NOTE

Operation in 2 1/2 minute or 30

minute OEI range is intended for

emergency use only, when one

engine becomes inoperative due to

an actual malfunction.

Anytime an engine is operated in an OE

range, an entry shall be made in the helicopter

logbook detailing the extent of operation inexcess of twin engine takeoff power limits

This does not apply to approved ITT limits for

starting.

GAS PRODUCER RPM (NI) LIMITS

TWIN ENGINE OPERATION

GAUGE P/N 212-075-037-101

GAUGE P/N 212-075-037-113

Continuous operation 0 to 150 amps

Caution 75 to 150 amps

Maximum continuous 150 amps (each)

Continuous operation 61 to 100.8%

Maximum continuous 100.8%

Maximum for takeoff 100.8%

Continuous operation 61 to 101.8%

Maximum continuous 101.8%

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1-12Rev. 2231 OCT 2007

ONE ENGINE INOPERATIVE (OEI)

GAUGE P/N 212-075-037-101

GAUGE P/N 212-075-037-113

POWER TURBINE RPM (NII) LIMITS

INTERTURBINE TEMPERATURE (ITT)LIMITS


CAUTION

INTENTIONAL USE OF ITT ABOVE

810C IS PROHIBITED DURING

NORMAL OPERATIONS EXCEPTDURING START.


FUEL PRESSURE LIMITS

OIL PRESSURE LIMITS

ENGINE

COMBINING GEARBOX

Maximum for takeoff 101.8%

30 minute OEI 100.8%

2 1/2 minute OEI range 100.8 to 102.4%

Maximum OEI 102.4%

30 minute OEI 101.8%

2 1/2 minute OEI range 101.8 to 103.4%

Maximum OEI 103.4%

Minimum in cruise

at or below 6000 feet HD

97%

Minimum for hover,

takeoff, and climb

100%

Minimum in cruise

above 6000 feet HD

100%

Operation with engine

torque at or below 30%

100 to 104.5%

Maximum with engine


104.5%

Maximum continuous 765C

Takeoff range

(5 minutes maximum)

765 to 810C

Maximum transient

(5 seconds maximum)

850C

Maximum for starting

(2 seconds maximum

above 960C)

1090C

Maximum continuous OEI 765C

30 minute OEI range 765 to 822C

2 1/2 minute OEI range 822 to 850C

Maximum OEI 850C

Minimum 4 PSI

Continuous operation 4 to 35 PSI

Maximum 35 PSI

Minimum for flight idle 40 PSI

Operation below 79%

NIRPM

40 to 80 PSI


Maximum 115 PSI


Operation below 94%

NIIRPM

40 to 60 PSI


Maximum 80 PSI

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31 OCT 2007Rev. 221-13

OIL TEMPERATURE LIMITS

ENGINE

COMBINING GEARBOX

ENGINE RESTART LIMITS

Above 15,000 feet (4572 m) pressure altitude,

restart shall be attempted in manual fuel

control mode only.

Below 15,000 feet (4572 m) pressure altitude,

restart may be attempted in either manual or

automatic fuel control mode.

ENGINE TORQUE LIMITS


Maximum allowable engine torque differentialis 4% during normal operation. Refer to

Transmission Torque Limits.


TRANSMISSION LIMITATIONSTRANSMISSION TORQUE LIMITS


WARNING

TAKEOFF POWER SHALL NOT BE

UTILIZED ABOVE 105 KIAS.

TRANSMISSION OIL PRESSURE LIMITS

TRANSMISSION OIL TEMPERATURE

LIMITS

ROTOR LIMITATIONS

ROTOR RPM (NR) LIMITS POWER ON

Minimum 0C

Continuous operation 0 to 115CMaximum 115C

Minimum 0C

Continuous operation 0 to 115C

Maximum 115C

Maximum continuous OEI 61%

30 minute OEI range 61 to 76%

Maximum OEI 76%

Maximum continuous 84%

Takeoff range

(5 minutes maximum)

84 to 100%

Maximum 100%


Flight idle range 30 to 40 PSI


Maximum 70 PSI

Continuous operation 15 to 110C

Maximum 110C

Minimum 97%

Continuous operation

at or below 6000 feet HD

97 to 100%

Continuous operation

above 6000 feet HD

100%

Maximum continuous 100%

Operation with engine


100 to 104.5%

Maximum with engine


104.5%

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1-14Rev. 2231 OCT 2007

ROTOR RPM (NR) LIMITS POWER OFF

ROTOR RPM (NR) LIMITS GROUND

OPERATION

ROTOR BRAKE LIMITATIONS

Engine starts with rotor brake engaged are

prohibited. Rotor brake application is limited

to ground operation and shall not be applied

until both engines are shut down and rotor

RPM has decreased to 40% NRor below.

FUEL AND OIL LIMITATIONS

NOTE

Refer to BHT-412-MD-1 for fuel

capacity and lists of approved fuels,

oils, and vendors.

FUEL

Fuel conforming to ASTM D-6615 Jet B, NATO

F-40, or MIL-DTL-5624 Grade JP-4 may be

used at all ambient air temperatures.

Fuel conforming to ASTM D-1655 Jet A,

limited to ambient air temperatures above

-30C (-22F).

Fuel conforming to ASTM D-1655 Jet A-1,

NATO F-44, MIL-DTL-5624 Grade JP-5, NATO

F-34, or MIL-DTL-83133 Grade JP-8, limited to

ambient air temperatures above -36C (-33F).

ENGINE AND COMBINING GEARBOX OIL

Oil conforming to PWA Specification No. 521

Type I and MIL-PRF-7808 (NATO O-148) may

be used at all ambient temperatures.

Oil conforming to PWA Specification No. 521

Type II and MIL-PRF-23699 (NATO O-156),limited to ambient temperatures above -40C(-40F).

TRANSMISSION, INTERMEDIATE AND

TAIL ROTOR GEARBOX OIL

Oil conforming to DOD-PRF-85734,

MIL-PRF-23699 (NATO O-156) , or

MIL-PRF-7808 (NATO O-148) may be used at

all approved ambient temperatures.

NOTE

DOD-PRF-85734 or MIL-PRF-23699 is

recommended.

HYDRAULIC LIMITATIONS

NOTE

Refer to BHT-412-MD-1 for approved

fluids and vendors.

Hydraulic fluid type MIL-PRF-5606 (NATO

H-515) sha l l be used a t a l l ambient

temperatures.

Both hydraulic systems shall be operative

prior to takeoff.

Minimum for autorotation

with gross weight below

8000 pounds (3629 kg)

80%

Power off operation withgross weight below 8000

pounds (3629 kg)

80 to 104.5%

Minimum for autorotation

with gross weight at or

above 8000 pounds

(3629 kg)

91%

Maximum 104.5%

Minimum 77%

Minimum with stick

centering indicator

system inoperative

97%

Transient (avoid steady

state operations)

26 to 77%

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WARNING

THE HELICOPTER IS NOT

CONTROLLABLE WITH BOTH

HYDRAULIC BOOST SYSTEMS

INOPERATIVE.

HYDRAULIC PRESSURE LIMITS

HYDRAULIC TEMPERATURE LIMITS

INSTRUMENT MARKINGS ANDPLACARDS

NOTE

Illustrations shown in Figure 1-5 are

artist representations and may or

may not depict actual approved

inst ruments due to pr int inglimitations. Instrument operating

ranges and limits shall agree with

those presented in this section.

Refer to Figure 1-5 for instrument range

markings and Figure1-3 for placards and

decals.

HEATER OPERATION

Heater shall not be operated when OAT isabove 21C (69.8F).

HOIST PENALTY REGION

Pilot shall know CG at time of hoist operation

to determine if CG is within penalty region of

Figure 1-6, Hoist CG envelope.

Each hoist operation performed is defined as

an extension and retraction of hoist cable

while hovering with any weight attached.

Refer to BHT-412-FMS-7 or BHT-412-FMS-26

for Bell Helicopter approved Hoists.

WARNING

THIS PENALTY REGION IS VALID

FOR ALL HOIST INSTALLATIONS.

OPERATION IN PENALTY REGION

AFFECTS AIRWORTHINESSLIMITATIONS OF ROTOR

COMPONENTS (REFER TO

BHT-412-MM).

Minimum 600 PSI

Caution 600 to 900 PSI


Maximum 1100 PSI

Maximum 88C

31 OCT 2007Rev. 221-14A/1-14B

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31 OCT 2007Rev. 221-15

Figure 1-5. Instrument Markings (Sheet 1 of 4)

412_FM_1_0002

AIRSPEED

DUAL TORQUE INDICATOR

TRANSMISSION (TWIN ENGINE OPERATION)

Indicator unreliable0 to 30 knots

Continuous operation30 to 140 knots

Continuous operation10 to 84%

5 minute takeoff range84 to 100%

TRIPLE TACHOMETER

ROTOR RPM (NR)

Transient ground operation26 to 77%

ENGINE RPM (NII)

Minimum97%

Continuous operation at or below

6000 feet HD

97 to 100%

Continuous operation above 6000 feet HD100%

Operation at or below

30% engine torque100 to 104.5%

Maximum at or below

30% engine torque104.5%

Minimum for autorotation below

8000 pounds (3629 kg) gross weight

80%

Power off operation below

8000 pounds (3629 kg) gross weight

80 to 91%

Maximum104.5%

Continuous operation power off

(91% minimum)91 to 104.5%

Maximum100%

ENGINE (ONE ENGINE INOPERATIVE)

Continuous OEI operation5 to 61%

30 minute OEI range61 to 76%

Maximum OEI76%

Maximum for autorotation at or

below 10,000 feet (3048 m) Hp

105 knots

VNE140 knots

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31 OCT 2007Rev. 222-1

Section 2NORMAL PROCEDURES

2

TABLE OF CONTENTS

Page

Subject Number

Introduction..................................................................................................................... 2-3

Operating Limitations..................................................................................................... 2-3

Flight Planning................................................................................................................ 2-3

Takeoff and Landing Data .......................................................................................... 2-3

Weight and Balance.................................................................................................... 2-3

Preflight Check................................................................................................................ 2-3

Before Exterior Check .................................................................................................... 2-5

Exterior Check................................................................................................................. 2-5

Interior Check.................................................................................................................. 2-7

Prestart Check................................................................................................................. 2-7

Engine Starting ............................................................................................................... 2-9

Engine 1 Start.............................................................................................................. 2-9

Engine 2 Start.............................................................................................................. 2-11

False Start........................................................................................................................ 2-12

Attempted Engine Start with No Lightoff.................................................................. 2-12

Dry Motoring Run........................................................................................................ 2-12

Systems Checks ............................................................................................................. 2-12Stick Centering Indicator Check................................................................................ 2-12

Force Trim Check........................................................................................................ 2-13

Engine Fuel Control Check ........................................................................................ 2-13

Fuel Crossfeed Valve Check...................................................................................... 2-13

Electrical Systems Check .......................................................................................... 2-13

AFCS Check ................................................................................................................ 2-14

Preliminary Hydraulic Check ..................................................................................... 2-15

Engine Runup.............................................................................................................. 2-15

Cabin Heater Check.................................................................................................... 2-15

Prolonged Ground Operation .................................................................................... 2-15

Hydraulic Systems Check.......................................................................................... 2-16

Before Takeoff................................................................................................................. 2-17Power Assurance Check............................................................................................ 2-17

Takeoff ............................................................................................................................. 2-17

In-flight Operation........................................................................................................... 2-18

Maneuvering with AFCS in SAS Mode...................................................................... 2-18

Maneuvering with AFCS in ATT Mode ...................................................................... 2-18

Before Landing................................................................................................................ 2-18

After Landing................................................................................................................... 2-19
http://412-fm-1%20page%202-17%20to%202-18.pdf/http://412-fm-1%20page%202-17%20to%202-18.pdf/http://412-fm-1%20page%202-17%20to%202-18.pdf/http://412-fm-1%20page%202-17%20to%202-18.pdf/http://412-fm-1%20page%202-17%20to%202-18.pdf/http://412-fm-1%20page%202-17%20to%202-18.pdf/http://412-fm-1%20page%202-17%20to%202-18.pdf/http://412-fm-1%20page%202-17%20to%202-18.pdf/http://412-fm-1%20page%202-17%20to%202-18.pdf/http://412-fm-1%20page%202-17%20to%202-18.pdf/

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2-2Rev. 2231 OCT 2007


Page

Subject Number

Engine Shutdown ........................................................................................................... 2-19

After Exiting Helicopter.................................................................................................. 2-20

LIST OF FIGURES

Figure Page


Preflight Check Sequence .................................................................... 2-1........... 2-4
http://412-fm-1%20page%202-17%20to%202-18.pdf/http://412-fm-1%20page%202-17%20to%202-18.pdf/http://412-fm-1%20page%202-17%20to%202-18.pdf/http://412-fm-1%20page%202-17%20to%202-18.pdf/

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31 OCT 2007Rev. 222-7

Hub and sleeve assembly Check condition.

Main rotor pitch l inks Security and

condition.

Main rotor hub Check general condition.

Mast retaining nut Secured.

Yoke assembly Condition.

Pitch horns Security and condition.

Elastomeric bearings, lead-lag dampers

Check general condition.

Blade retention bolts Security and

proper latching.

Droop restrainers Security and

condition. Verify droop stop clevis is inlower position of cam plate.

Simple pendulum absorbers (if installed)

Security and condition.

Rotor blades Visually check condition and

cleanliness.

Main driveshaft and couplings Condition,

secur i ty , and grease leakage. Check

Temp-Plates (four places each coupling) for

evidence of elevated temperature, indicatedby dot changing color to black.

CAUTION

IF ANY TEMP-PLATE IS MISSING OR

HAS BLACK DOTS, MAINTENANCE

PERSONNEL SHALL ASSIST IN

DETERMINING AIRWORTHINESS.

Transmission oil filler cap Secured.

No. 1 and No. 2 h ydraulic reservoirs

Visually check fluid levels; caps secured.

Antenna(s) Condition and security.

Combining gearbox oil filler cap Secured.

Anticollision light Condition and security.

No. 1 and No. 2 engine air intakes Covers

removed; unobstructed. Check particle

separator doors closed.

Engine and transmission cowling Secured.

Fresh air inlet screen Unobstructed.

Rotor brake reservoir cap Security.

CAUTION

IF HELICOPTER HAS BEEN

EXPOSED TO SNOW OR ICING

CONDITIONS, SNOW AND ICE

SHALL BE REMOVED PRIOR TO

FLIGHT.

INTERIOR CHECK

Cabin interior Cleanliness and security of

equipment.

Cargo and baggage (if applicable) Check

security.

Protective breathing equipment (if installed)

Condition and properly serviced.

NOTE

Opening or removing doors shifts

helicopter center of gravity and

reduces VNE. Refer to Weight and

Balance section in Manufacturers

Data and to Doors Open or Removed

limitations.

Passenger doors Secured.

PRESTART CHECK

Seat and pedals Adjust.

Seat belt and shoulder harness Fasten and

adjust.

Shoulder harness inertia reel and lock

Check.

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2-8Rev. 2231 OCT 2007

Directional control pedals Check freedom

of movement; position for engine start.

Collective control head switches OFF.

Transmission chip detector indicators

Check; reset if required.

Lower pedestal circuit breakers IN.

Radio equipment OFF.

COMPASS SLAVING switch(es) MAG (slave

position).

FUEL INTCON switch NORM.

BOOST PUMP switches OFF.

FUEL XFEED switch NORM.

FUEL switches OFF.

PART SEP switches NORM.

GOV switches AUTO.

HYDR SYS switches ON.

STEP switch (if installed) STOW.

ROTOR RPM audio switch Spring loaded to

AUDIO.

FORCE TRIM switch ON.

Instruments Static check.

APPROACH PLATE AND MAP LIGHT knob(s)

OFF.

AUX SYS PITOT and STATIC switches (if

installed) NORM.

Altimeter(s) Set.

Clock Set and running.

FIRE EXT switch OFF.

FIRE PULL handles In (forward).

AFT DOME LIGHT rheostat OFF.

PITOT STATIC HEATERS switch OFF.

WIPER select switches OFF.

CARGO RELEASE switch OFF.

HEATER switch OFF.

AFT OUTLET switch OFF.

VENT BLOWER switch OFF.

EMERG LT switch (if installed) DISARM.

STBY ATT switch (if installed) ON; check

standby attitude indicator light illuminates

and OFF flag retracts, then switch OFF.

Overhead circuit breakers In.

All LT rheostats OFF.

UTILITY LIGHT switch OFF.

MASTER CAUTION switch (overhead)

Spring loaded to NORMAL.

EXTERIOR LIGHT switches As required.

EMERG LOAD switch NORMAL.

NON-ESNTL BUS switch Spring loaded to

NORMAL.

INV 1 and 2 switches OFF.

GEN 1 and 2 switches OFF.

CAUTION

IF EXTERNAL POWER IS USED

CONNECT (1000 AMPS MAXIMUM).

CHECK 27 1 VDC; ADJUST POWER

SOURCE IF REQUIRED.

BATTERY switches (BUS 1 and BUS 2) ON;

check BATTERY caution light illuminates.

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NOTE

Test operate all lights when night

flights are planned or anticipated.

Accomplish light tests with external

power connected or during engine

runup.

MASTER CAUTION switch (overhead)

TEST; check a l l caut ion panel l ights

extinguish except CAUTION PANEL segment

and MASTER CAUTION light. (Both ENG OUT

lights and RPM light will dim during test.)

Return to NORMAL.

31 OCT 2007Rev. 222-8A/2-8B

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2-18Rev. 2231 OCT 2007

NOTE

Downwind takeof fs are not

recommended since the published

takeoff distance performance will not

be realized.

During takeoff, pitch attitude must be

adjusted commensurate with power

application to prevent entering the

AVOID area of the Height-Velocity

diagram. Torque shall not exceed

15% above IGE hover power while

accelerating to Takeoff Climbout

Speed (Section 4).

Cyclic control Apply forward cyclic to

accelerate smoothly.

Collective pitch Adjust as desired after

reaching VTOCS(45 KIAS).

Airspeed Within limits (60 KIAS minimum

for IFR).

IN-FLIGHT OPERATION

CAUTION

FOR FLIGHT OPERATIONS ABOVE

6000 FEET HD, MAINTAIN 100% NR/

NII.

Airspeed Within limits for flight altitude.

Engine , gearbox, and t ransmiss ion

instruments Within limits.

NOTE

Maximum pitch attitude capability of

standby attitude indicator is 60.

Refer to applicable operating rules

for h igh a l t i tude oxygen

requirements.

MANEUVERING WITH AFCS IN SAS

MODE

Use normal pilot control techniques.

MANEUVERING WITH AFCS IN ATT MODE

Depress cyclic FORCE TRIM release button

and maneuver as desired. Release button

when desired attitude is reached. Helipilot will

hold attitude until retrimmed to new attitude.

Attitude may also be adjusted with cyclic

ATTD TRIM switch.

For momentary attitude changes, manual

cyclic movement may be used; however,

AFCS actuators may be saturated to limit

authority when cyclic is moved manually.

NOTE

In-flight use of VG FAST ERECT

button will disengage the respective

helipilot and decouple the automatic

flight control modes.

BEFORE LANDING

Flight controls Adjust friction as desired.

AFCS Engage ATT or SAS mode as

desired.

FORCE TRIM switch ON in ATT mode; as

desired in SAS mode.

Throttles Full open.

NIIRPM 100%.

Flight path Stay clear of AVOID area of

Height-Velocity diagram. For landing distance

information in the event of engine failure

during approach, refer to Section 4.

Passenger steps As desired.

ENG 97 to 100% Continuous operation at

or below 6000 feet HD

100% Continuous operation

above 6000 feet HD

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31 OCT 2007Rev. 222-19

CAUTION

RUN-ON LANDINGS MAY RESULT IN

ROLL OSCILLATIONS WHILE ON

THE GROUND. IF THIS OCCURS,

LOWERING COLLECTIVE FULL

DOWN OR TURNING SCAS OFF

WILL STOP THE OSCILLATIONS.

AFTER LANDING

Collective pitch Full down.

Pedals Centered.

FORCE TRIM switch ON.

FORCE TRIM release button Depress and

check for actuator centering.

AFCS SAS mode.

CAUTION

IF STICK CENTERING INDICATOR

SYSTEM IS INOPERATIVE, NRFOR

GROUND OPERATION SHALL BE

97% OR ABOVE.

Stick centering check Complete; center

cyclic as necessary to extinguish CYC CTR

caution lights.

NOTE

On side slopes greater than 5,

disregard CYC CTR caution lights

and position cyclic as required.

ENGINE SHUTDOWN

HP 1 and HP 2 Disengage; check helipilot

lights extinguish and AFCS and MASTER

CAUTION lights illuminate.

Cyclic Frictioned as desired. Maintain

cyclic stick as near center as possible at all

rotor speeds.

NOTE

Minimize b lade f lapping by

maintaining highest rotor RPM (NR)

within allowable range.

Throttles Reduce to 77 85% NR.

ITT Stabilize for 1 minute.

ELT (if installed) Check for inadvertent

transmission.

Radios OFF.

Engine instruments Within limits.

IDLE STOP release switch ENG 1 position.

Engine 1 throttle Full closed. Check ITT and

NIRPM decreasing.

IDLE STOP release switch ENG 2 position.

Engine 2 throttle Full closed. Check ITT and

NIRPM decreasing.

Engine 1 and 2 FUEL switches OFF.

Engine 1 and 2 BOOST PUMP switches

OFF.

GEN 1 and 2 switches OFF.

INV 1 and 2 switches OFF.

STBY ATT switch (if installed) OFF.

EMERG LT switch (if installed) DISARM.

WARNING

DO NOT USE COLLECTIVE TO SLOW

ROTOR RPM. USE OF COLLECTIVE

TO SLOW ROTOR CAN CAUSE

EXCESSIVE CONING AND/OR

FLAPPING.

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2-20Rev. 2231 OCT 2007

CAUTION

AVOID RAPID ENGAGEMENT OF

ROTOR BRAKE IF HELICOPTER IS

ON ICE OR OTHER SLIPPERY OR

LOOSE SURFACE TO PREVENT

ROTATION OF HELICOPTER.

Rotor brake As desired. Apply at or below

40% rotor RPM. Return to stowed position

after main rotor stops.

Pilot Remain at flight controls until rotor

has come to a complete stop.

Lighting and miscellaneous switches OFF.

BATTERY switches OFF.

Collective down lock Secured as desired.

AFTER EXITING HELICOPTER

If conditions require, perform the following

(re fer to BHT-412-MD-1 for addi t ional

information):

Check general condition of droop restraint

system and verify that the droop restraint

arms are engaged in the lower detent of the

cam window.

Install main rotor blade tie-down socks on

blades and secure to mooring points.

Install tail rotor tie-down strap and secure to

vertical fin.

Install exhaust covers, engine inlet protective

plugs, and pitot tube covers.

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31 OCT 2007Rev. 223-1

Section 3EMERGENCY/MALFUNCTION PROCEDURES

3

TABLE OF CONTENTS

Paragraph Page


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

Definitions .............................................................................................. 3-2 ........... 3-3

Engine..................................................................................................... 3-3........... 3-3

Single Engine Failure ........................................................................ 3-3-A ....... 3-3

Engine Restart in Flight..................................................................... 3-3-B ....... 3-4Dual Engine Failure ........................................................................... 3-3-C ....... 3-6

Engine Underspeed ........................................................................... 3-3-D ....... 3-6

Engine Overspeed Fuel Control/Governor Failure..................... 3-3-E ....... 3-7

Engine Overspeed Driveshaft Failure ......................................... 3-3-F........ 3-9

Engine Compressor Stall .................................................................. 3-3-G....... 3-9

Engine Hot Start/Shutdown .............................................................. 3-3-H ....... 3-9

Engine Oil Hot .................................................................................... 3-3-I......... 3-10

Fire .......................................................................................................... 3-4........... 3-10

Engine Fire ......................................................................................... 3-4-A ....... 3-10

Cabin Smoke or Fumes ..................................................................... 3-4-B ....... 3-11

Baggage Compartment Fire.............................................................. 3-4-C ....... 3-11

Tail Rotor ................................................................................................ 3-5........... 3-11Complete Loss of Tail Rotor Thrust................................................. 3-5-A ....... 3-12

Tail Rotor Fixed Pitch Failures ......................................................... 3-5-B ....... 3-13

Loss of Pitch Change Control Linkage............................................ 3-5-C ....... 3-15

Hydraulic System................................................................................... 3-6........... 3-15

Electrical System................................................................................... 3-7........... 3-16

DC Power Failure ............................................................................... 3-7-A ....... 3-16

AC Power Failure ............................................................................... 3-7-B ....... 3-16

Fuel System............................................................................................ 3-8 ........... 3-17

Fuel Boost Pump Failure................................................................... 3-8-A ....... 3-17

Fuel Filter Partially Blocked.............................................................. 3-8-B ....... 3-17

Automatic Flight Controls System....................................................... 3-9........... 3-17AFCS Fails to Engage or Disengages.............................................. 3-9-A ....... 3-17

AFCS Fails to Hold Attitude .............................................................. 3-9-B ....... 3-18

AFCS Hardover or Abnormal Control Disturbance ........................ 3-9-C ....... 3-18

Autotrim Runaway ............................................................................. 3-9-D ....... 3-18

Communication System........................................................................ 3-10......... 3-19

Intercom Failure ................................................................................. 3-10-A..... 3-19

Communication Radio Failure .......................................................... 3-10-B..... 3-19

Cabin Heater........................................................................................... 3-11......... 3-19

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Paragraph Page


Landing Gear.......................................................................................... 3-12......... 3-19

Static Port Obstruction ......................................................................... 3-13......... 3-20Stick Centering Indicator Failure ......................................................... 3-14......... 3-20

LIST OF TABLES

Table Page


Warning (Red) Lights ............................................................................ 3-1........... 3-21

Caution (Amber) Lights......................................................................... 3-2........... 3-23

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31 OCT 2007Rev. 223-3

Section 3EMERGENCY/MALFUNCTION PROCEDURES

33-1. INTRODUCTION

The fo l lowing procedures conta in the

indications of equipment or system failure or

malfunction, the use of emergency features of

primary and backup systems, and appropriate

warnings, cautions, and explanatory notes.

Table 3-1lists fault conditions and corrective

actions required for illumination of red

warning l ights . Ta b le 3 - 2 addresses

malfunction procedures associated withamber caution lights.

All corrective action procedures listed herein

assume the pilot gives f irst priority to

helicopter control and a safe flight path.

The helicopter should not be operated

fol lowing any emergency landing or

shutdown until the cause of the malfunction

has been determined and correct ive

maintenance action taken.

3-2. DEFINITIONS

The following terms indicate the degree of

urgency in landing the helicopter.

The following terms are used to describe the

operating condition of a system, subsystem

assembly, or component.

3-3. ENGINE

3-3-A. SINGLE ENGINE FAILURE

The NIIRPM of the normally operating engine

is allowed to droop to 97% during transition

from twin engine operation to single engine

operation. The NIIRPM should be increased to

100% if possible.

Flight can be continued on remaining engineuntil a desirable landing site is available

There are certain combinations of gross

weight , a l t i tude , and cold ambient

temperatures at which a single engine

approach will result in the OEI torque limit

being exceeded. A run-on landing at 20 to 30

knots is recommended.

LAND AS SOON AS

POSSIBLE

Land without delay at

the nearest suitable

area (i.e, open field) at

which a safe approach

and landing is

reasonably assured.

LAND AS SOON AS

PRACTICAL

The duration of the

flight and landing site

are at the discretion of

the pi lot . Extended

f l ight beyond the

nearest approved

landing area is not

recommended.

Affected Fails to operate in the

in tended or usua l

manner.

Normal Operates in the

in tended or usua l

manner.

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CAUTION

RUN ON LANDINGS MAY RESULT IN

ROLL OSCILLATIONS WHILE ON

THE GROUND. IF THIS OCCURS,

DISENGAGING HP 1 AND HP 2 WILL

STOP THE OSCILLATIONS.

Loss of an engine while hovering at high

gross weight and extremely cold conditions

will most likely result in exceeding the OEI

torque limit. If an overtorque is observed or

suspected, an appropriate logbook entry shall

be made. Refer to performance charts in

Section 4.

NOTE

If an engine restar t is to be

attempted, refer to paragraph 3-3-B,

Engine Restart in Flight.

INDICATIONS:

ENG 1 OUT or ENG 2 OUT warning light

illuminated.

NIRPM below 53% and decreasing.

NIIRPM below 85% and decreasing.

ITT below 400C and decreasing.

NO. 1 or 2 OIL PRESSURE, DC

GENERATOR, and PART SEP OFF

caution lights illuminated.

Normal engine NIIRPM droops to 97%.

PROCEDURE:

WARNING

IF CORRECTIVE ACTION IS NOT

INITIATED IMMEDIATELY, ROTOR

RPM COULD DECAY EXCESSIVELY.

CAUTION

DURING COLD WEATHER

OPERATIONS, CAREFULLY

MONITOR TORQUE OF THE

NORMAL ENGINE WHEN ONE

ENGINE FAILS OR IS SHUT DOWN IN

FLIGHT.

Collective Reduce as required to

maintain rotor RPM and power within OEI

limits.

Airspeed 70 KIAS or as required to

maintain flight within OEI limits.

RPM switch INCR; set NIIRPM at 100%

if possible.

Throttle (affected engine) Closed.

BOOST PUMP switch (affected engine)

OFF.

FUEL switch (affected engine) OFF.

FUEL XFEED switch OVRD CLOSE.

Fuel INTCON switch OPEN.

GEN switch (affected engine) OFF.

NON-ESNTL BUS As desired.

BATTERY BUS 2 switch ON.


MASTER CAUTION light Reset.

Altitude Descend below 5000 feet HP(if practical) to prevent possible fuel

starvation if remaining boost pump fails.

Land as soon as practical.

3-3-B. ENGINE RESTART IN FLIGHT

The conditions which would warrant an

attempt to restart the engine would probably

be a flameout, caused by a malfunction of the

automatic mode of the fuel control unit. The

decision to attempt an engine restart during

flight is the pilots responsibility.

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31 OCT 2007Rev. 223-5

PROCEDURE:

CAUTION

IF THE CAUSE OF ENGINE FAILURE

IS OBVIOUSLY MECHANICAL, AS

EVIDENCED BY ABNORMAL

SOUNDS, DO NOT ATTEMPT A

RESTART.

Throttle (affected engine) Closed.

BOOST PUMP switch (affected engine)

ON.

FUEL switch (affected engine) ON.

FUEL XFEED switch NORM.

GOV switch (affected engine)

MANUAL.

GEN switch (affected engine) OFF.

CAUTION

OEI PERFORMANCE CAN BE

AFFECTED DURING GENERATOR-

ASSISTED START (WITH BOTHBATTERY SWITCHES ON).

For battery start (non-assisted):

BATTERY BUS switch (normal engine)

OFF.

BATTERY BUS switch (affected engine)

ON.

START switch Engage; observe starter

limitations.

Engine oil pressure Indicating a rise.

CAUTION

WHEN RESTARTING ENGINE IN

MANUAL FUEL CONTROL MODE,

CAREFULLY MONITOR ITT.

Throttle Open slowly at 12% NI RPM

until ITT begins to rise. Do not open

throttle further until ITT and N IRPM

stabilize.

START switch Centered at 55% N

RPM.

CAUTION

WHEN OPERATING IN MANUAL

FUEL CONTROL MODE, MAKE

SLOW, SMOOTH THROTTLE

MOVEMENTS TO AVOID

COMPRESSOR STALL, OVERTEMP,

OVERSPEED, AND POSSIBLE

DRIVETRAIN DAMAGE.

COORDINATE THROTTLE AND

COLLECTIVE PITCH CHANGES TO

AVOID OVERLOADING THE

NORMAL ENGINE.

Throttle Increase slowly; adjust as

required to control torque, ITT, and N

RPM.

NOTE

If torque of af fected engine is

controlled slightly (approximately

4%) below torque of normal engine,

rotor RPM will be governed within

limits automatically by normal

engine.

GEN switches (both) ON.


FUEL INTCON switch NORM.


If restart was unsuccessful, secure affected

engine as prescribed in paragraph 3-3-A

Single Engine Failure.

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3-6Rev. 2231 OCT 2007

3-3-C. DUAL ENGINE FAILURE

INDICATIONS:

ENG 1 OUT and ENG 2 OUT warning

lights illuminated.

RPM warning light illuminated.

Rotor RPM audio on.

NIRPM below 53% and decreasing (both

engines).

NIIRPM below 85% and decreasing (both

engines).

ITT below 400C and decreasing (both

engines).

No. 1 and 2 OIL PRESSURE, DC

GENERATOR, and PART SEP OFF

caution lights illuminated.

PROCEDURE:

WARNING




Collective pitch Reduce. Establish

autorotative glide at 65 to 90 KIAS.

NOTE

AIRSPEED for best angle of glide in

autorotat ion is 90 KIAS, and

AIRSPEED for minimum rate of

descent is 65 KIAS. Autorotational

rate of descent is a function of

AIRSPEED and ROTOR RPM and is

virtually unaffected by gross weightand density altitude.

Accomplish autorotative landing.

If time permits before landing and a restart

will not be attempted, proceed as follows:

Throttles (both) Closed.

BOOST PUMP switches (both) OFF.

FUEL switches (both) OFF.

After landing, complete shutdown.

3-3-D. ENGINE UNDERSPEED

NOTE

Normal deviations of ROTOR RPM

from the governed setting may occur

when large collective changes are

made, but should not be confused

with fuel control failure unless a

large steady-state TORQUE split

occurs.

If there is a low power demand (less thansingle engine power available) at the time of

low side failure, ROTOR RPM and ENG RPM

(NII) of the affected engine will decrease and

stabilize at or slightly below the governed

value. Torque, ITT, and GAS PROD RPM (NI) of

the affected engine will also decrease. As

ROTOR RPM decreases, the normal engine

will increase TORQUE output to assume the

load. If power demand is near zero, there may

not be a significant torque split.

If there is a high power demand (greater thansingle engine power available) at the time of

low side failure, ROTOR RPM will decrease

along with ENG RPM (NII), TORQUE, ITT, and

GAS PROD RPM (NI) of the affected engine.

As ROTOR RPM decreases, the normal engine

will increase to maximum power to assume

the load, causing significant increase in

TORQUE, ITT, and GAS PROD RPM (N I), while

ENG RPM (NII) will remain below the governed

value.

INDICATIONS:

Low ENG RPM (NII) and ROTOR RPM

(possibly with RPM warning light and

audio if power demand is in excess of

single engine power available).

TORQUE split (proportional to power

demand).

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31 OCT 2007Rev. 223-7

Low GAS PROD RPM (NI), ITT, and

TORQUE on affected engine.

PROCEDURE:

WARNING




Collective Adjust as necessary to

maintain ROTOR RPM.

Airspeed 70 KIAS or as required to

maintain flight within OEI limits.

Affected engine Identify.

Throttle frictions Tighten on normal

engine; reduce on affected engine.

Throttle (affected engine) Reduce to

flight idle.


MANUAL.

CAUTION



SLOW, SMOOTH THROTTLE

MOVEMENTS TO AVOID


OVERSPEED, AND POSSIBLE

DRIVETRAIN DAMAGE.

COORDINATE THROTTLE AND

COLLECTIVE PITCH CHANGES TO

AVOID OVERLOADING THE

NORMAL ENGINE.

Throttle (affected engine) Increase

slowly. Adjust throttle and collective as

required to maintain TORQUE of affected

engine slightly below TORQUE of normal

engine.

MASTER CAUTION light Reset.


3-3-E. ENGINE OVERSPEED FUELCONTROL/GOVERNOR FAILURE

NOTE

Normal deviations of ROTOR RPM

from the governed setting may occurwhen large collective changes are

made, but should not be confused

with fuel control failure unless a

large steady-state TORQUE split

occurs.

If there is a low power demand (less than

single engine power available) at the time of

high side failure, ROTOR RPM and ENG RPM

(N I I) of the affected engine will increase

considerably above the governed value

TORQUE, ITT, and GAS PRODUCER RPM (NI)of the affected engine will also increase. As

ENG RPM (N I) and ROTOR RPM increase

above the governed value, the normal engine

wi l l reduce power to keep i tse l f f rom

overspeeding, and will indicate significantly

lower TORQUE, ITT, and GAS PROD RPM (N I)

than the affected engine.

If there is a high power demand (greater than

single engine power available) at the time of

high side failure, ROTOR RPM and ENG RPM

(NII) of the affected engine will surge initiallyalong with TORQUE, ITT, and GAS PROD RPM

(N I). As ENG RPM (N I I) and ROTOR RPM

increase, the normal engine will reduce power

to keep itself from overspeeding. The affected

engine then tries to assume all the load

which is beyond its capability due to the high

power demand. ENG RPM (NII) of the affected

engine (and ROTOR RPM) will then decrease

and rejoin the ENG RPM (N II) of the norma

engine, stabilizing at or slightly above the

governed value as the normal engine adjusts

power output to share the load.

INDICATIONS:

High ENG RPM (NII) and ROTOR RPM

possibly with RPM warning light.

Definite TORQUE split (proportional to

power demand).

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3-8Rev. 2231 OCT 2007

High GAS PROD RPM (NI), ITT, and

TORQUE on affected engine.

Return of ENG RPM (NII) and ROTOR

RPM to governed value (if power demand

is high).

PROCEDURE:

CAUTION



RPM CAN OVERSPEED

EXCESSIVELY.

Collective Adjust as necessary to

maintain ROTOR RPM.

Affected engine Identify.


maintain TORQUE at or slightly below

TORQUE of normal engine.

If affected engine does not respond to

throttle inputs:

Throttle frictions Tighten on normal

engine; reduce on affected engine.


idle.


MANUAL.

CAUTION



SLOW, SMOOTH, COORDINATED

THROTTLE AND COLLECTIVE

MOVEMENTS TO AVOID


UNDERSPEED/OVERSPEED, AND

POSSIBLE DRIVETRAIN DAMAGE.

Throttle (affected engine) Increase

slowly. Adjust throttle and collective as

required to maintain TORQUE of affected

engine slightly below TORQUE of normalengine.

MASTER CAUTION Reset.

CAUTION

IF NROR TRANSMISSION TORQUE

EXCEEDS 110% OR OVERSPEED

VALUES ARE UNKNOWN, LAND AS

SOON AS POSSIBLE.


3-3-E-1. GOVERNOR ACTUATOR FAILURE

(FULL INCREASE)

INDICATIONS:

NII and rotor RPM increase to

approximately 101%.

RPM INCR-DECR switch inoperative.

PROCEDURE:

If this failure occurs during takeoff or

landing, no immediate corrective action

is necessary to complete e i ther

maneuver.

As soon as practical, roll back both

throttles to maintain 97 to 100% NIIRPM.

Further adjustment of collective andthrottles simultaneously will allow full

power at pilots discretion.

3-3-E-2. GOVERNOR ACTUATOR FAILURE

(FULL DECREASE)

Published Flight Manual performance may not

be attainable.

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31 OCT 2007Rev. 223-9

3-3-F. ENGINE OVERSPEED DRIVESHAFT FAILURE

WARNING

FAILURE OF THE MAIN

DRIVESHAFT TO THE

TRANSMISSION WILL RESULT IN

COMPLETE LOSS OF POWER TO

THE MAIN ROTOR. ALTHOUGH THE

COCKPIT INDICATIONS FOR A

DRIVESHAFT FAILURE ARE

SOMEWHAT COMPARABLE TO A

DUAL ENGINE FAILURE, IT IS

IMPERATIVE THAT AUTOROTATIVE

FLIGHT PROCEDURES BE

ESTABLISHED I

Documents

412-FM-1_Rev_22