C550GT ICA v.8 11-09-2020 copy

MAINTENANCE MANUAL SUPPLEMENT 25-60-00-Aircraft Emergency Location System
C550GT-AD016-FU24-0213
Aircraft Emergency Location System Revision: Initial Issue DATE: 01/01/2020

AELS Description and Operation / AELS
Aircraft Emergency Location System
25-60-00 AELS
Aircraft Emergency Location System (AELS).
Description and Operation

Description and Operation

The aircraft has an Artex ME406 Aircraft Emergency Location System (AELS).
The system has a transmitter unit, a remote controller, an antenna with feeder, and interconnect wiring.

Figure 25.1 AELS Components

Maintenance Practices

For all AELS maintenance and test requirements,
Ref. Ext. Doc: NZCAA Advisory Circular AC43-11 Rev.3

WARNING: OBEY CIVIL AVIATION AUTHORITY RULES FOR THE ACTIVE TESTING OF THE AELS. MAKE SURE
YOU MONITOR THE VHF RADIO ON EMERGENCY FREQUENCY 121.500 MHZ DURING THE TEST.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 27-00-00 - Flight Controls DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Flight Controls
Chapter 27

Title Page

Chapter 27
Flight Controls

Chapter 27 Flight Controls

MAINTENANCE MANUAL SUPPLEMENT 27-00-00 - Flight Control System
C550GT-AD016-FU24-0213
Chapter Content Revision: Initial Issue DATE: 01/01/2020

Chapter Content Flight Control System
Flight Control System

Chapter Contents

Chapter 27 Flight Controls

Applicable Section Guide
27-00-00 Flight Control System
Description and Operation
> Stall Warning System.
27-10-00 Aileron Control
> Aileron Control System.
> Aileron Direct Pulley.
> Aileron Direct Cables.
27-20-00 Rudder Control
> Rudder Control System.
27-30-00 Stabilator Control
Description and Operation
> Stabilator Control System.
> Stabilator Trim Control System.
> Trim Selector Switch and Override Relay.
27-30-01 Electric Stabilator Trim
Description and Operation
> Electric Stabilator Trim Control.
Maintenance Practices

Removal and Installation
> Trim Selector Switches
> Trim Selector Switch Removal.
> Trim Selector Switch Installation.
27-50-00 Flap Control System
> Description and Operation
> Transfer Lever Assembly Removal and Installation.
> Flap System Rigging.
Maintenance Practices
Removal and Installation
> Flap Cable and Transfer Lever Assembly Removal.
> Flap Cable and Transfer Lever Assembly Installation.
Adjustment and Test
> Flap System Rigging.

MAINTENANCE MANUAL SUPPLEMENT 27-00-00 - Manual to Use DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Manual to Use
Chapter Guide

Chapter Guide
Manual to Use

Applicable Section Guide MANUAL TO USE
SECTION / SUB-SECTION
N/A FU24-954 C550GT
27-00-00 Flight Controls
Description and Operation 

C550GT Flight Control System - Differences 
Lateral Control 
Directional Control 
Longitudinal Control 
Flap
Control Column Lock 
Stall Warning (see Chp. 31)
27-10-00 Aileron Control System 
Description and Operation
Aileron Control -Description / Operation / Differences 
Maintenance Practices 
Servicing 
Removal and Installation
Adjustment and Test 
27-20-00 Rudder Control System
Description and Operation 
Rudder Control -Description / Operation 
Maintenance Practices
Servicing 
Removal and Installation
27-30-00 Stabilator Control System 
Description and Operation 
Stabilator Controls -Description / Differences 
Maintenance Practices
Servicing 
Removal and Installation
Adjustment and Test 
27-30-01 Electric Stabilator Trim Control 
Description and Operation
Electric Stabilator Trim Controls 
Maintenance Practices
Servicing
Removal and Installation
Stabilator Trim Switch

MAINTENANCE MANUAL SUPPLEMENT 27-00-00 - Manual to Use DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Manual to Use
Chapter Guide
MANUAL TO USE
Applicable Section Guide
SECTION / SUB-SECTION N/A FU24- 954 C550GT

Adjustment and Test 
Stabilator Control System Rigging 
Stabilator Trim Control Rigging 
Stabilator Balancing 
Trim System Indicator

27-50-00 Flap Control System 
Description and Operation

Flap Control System -Description / Operation / Differences 
Maintenance Practices
Servicing 
Removal and Installation
Adjustment and Test

Flap Rigging

MAINTENANCE MANUAL SUPPLEMENT 27-00-00-Flight Control System
C550GT-AD016-FU24-0213
Flight Control System Revision: Initial Issue DATE: 01/01/2020

Flight Control System Description and Operation / Flight Controls
Flight Controls

27-00-00 Flight Control System

Description and Operation

Description & Operation.

As the arrangement of the C550GT flight control system is unchanged, the FU24-954 Maintenance Manual
Chapter 27 - General Description is an acceptable reference. However, because of the extended fuselage of the
C550GT, changes to control cable length are necessary. This STC introduces extended length aileron direct,
rudder and stabilator cables. Routing is the same on all systems.

Aileron Control.

The length of each aileron-direct cable changes. The wing spar pulley and guards have minor modifications, but
the location of the pulley and mount bracket is unchanged. Chapter 27-10-00 gives more information.
See Chp. 27 Aileron Control System.

Rudder Control.

This modification increases the length of the Rudder Control cables.
Chapter 27-20-00 gives more information. See Chp. 27 Rudder Control System.
Stabilator Control.
This modification increases the length of the Stabilator Control cables.
Chapter 27-30-00 gives more information. See Chp. 27 Stabilator Control System.

NOTE: The Crusader Aircraft Company considers it is more correct to define the Elevator as a Stabilator. See
Chapter 55 Stabilisers and 27-30-00 Stabilator Control for more information on this system.

Stabilator Trim Control.

The general arrangement of the Stabilator Trim control system is unchanged.
Use the FU24-954 MM (Elevator Trim) for Stabilator Trim system maintenance. There are improvements to the
electrical system that controls the stabilator trim, refer to Section 27-30-00 Electric Stabilator Trim for
information on changes and maintenance. See Chp. 27 Electric Stabilator Trim Control.

Flap Controls.

The Flap Control System uses a transfer lever and different cable routing due to the wider outlet hopper.
Chapter 27-50-00 gives more information. See Chp. 27 Flap Control System

Cables - General

All C550GT flight control cables are constructed with galvanised cable.
The advantages of galvanised cable are its wear resistance and cost. Galvanised cables resist abrasion wear four
or five times longer than stainless steel. The bending of a wire rope causes the individual wire stands to not only
bend but to rub against one another. Galvanising is a natural lubricant. The individual wires can move easily with
very little friction and wear.
Stainless steel wire is high in nickel and much softer than the carbon steel wire. Stainless steel cable will show
signs of wire wear at pulleys and fairleads much quicker than galvanized carbon steel wire.
Therefore, the Crusader Aircraft Company recommend using galvanised steel cables. Refer to the Components
Changed By this STC Table, Chapter 27.

Stall Warning System.

The FU24-954 Maintenance Manual gave information about the Stall Warning System in Chapter 27.
Information for this warning system, now called the Lift Detector System, is provided in Chapter 31- Indicating
and Recording Systems in this C550GT Maintenance Manual Supplement. See Chp. 31 Lift Detector Components

Page 1

MAINTENANCE MANUAL SUPPLEMENT 27-00-00 - Components Changed Table
C550GT-AD016-FU24-0213
Components Changed Table Revision: Initial Issue DATE: 01/01/2020

Components Changed Table CCBTS / Flight Controls
Flight Controls

Table 27(a) - Components Changed By This STC

Drawing Number Item Part Number Description / Location

27-10-00 Aileron Control System

AD-550GT-2700-001-000 1 08-45031-1 Control Column

AD-550GT-2700-001-000 2 1460 Grip

AD-550GT-2700-001-000 3 7205-J50-Z-Q-E Elev. Trim Rocker Switch

AD-550GT-2710-001-000 1 08-45311-1 Cable Retainer

AD-550GT-2710-001-000 4 MS20220-2 Pulley

AD-550GT-2710-001-000 6 NAS304-36-1232 Cable Assembly

AD-550GT-2710-001-000 7 NAS304-36-1850 Cable Assembly

AD-550GT-2710-001-000 8 NAS304-37-0347 Cable Assembly

AD-550GT-2710-001-000 9 NAS304-37-0545 Cable Assembly

AD-550GT-2710-001-000 10 NAS304-37-2084 Cable Assembly

27-20-00 Rudder Control System

AD-550GT-2720-001-000 1 NAS304-27-3262 Cable Assembly

AD-550GT-2720-001-000 2 NAS304-27-3554 Cable Assembly

27-30-00 Stabilator & Trim Control System

AD-550GT-2730-001-000 1 NAS304-26-2783 Cable Assembly

AD-550GT-2730-001-000 2 NAS304-26-2803 Cable Assembly

AD-550GT-2730-001-000 3 NAS304-27-0372 Cable Assembly

AD-550GT-2730-001-001 6A1 AD2730210 Trim Drive Controller

27-50-00 Flap Control System

AD-550GT-2750-002-000 1 AD-550GT-2750-002-010 Transfer Lever

AD-550GT-2750-002-000 2 AD-550GT-2750-002-020 Bearing

AD-550GT-2750-002-000 3 AD-550GT-2750-002-030 Stop

AD-550GT-2750-002-000 4 AD-550GT-2750-002-100 Torque Tube Assembly

AD-550GT-2750-002-000 5 AD-550GT-2750-002-200 Axle

AD-550GT-2750-002-000 6 AD-550GT-2750-002-300 Link Rod Assembly

AD-550GT-2750-002-000 7 AD-550GT-2750-002-302 Bush

AD-550GT-2750-002-000 17 CAB-F-36-90-892 Cable Assembly

Page 1

MAINTENANCE MANUAL SUPPLEMENT 27-10-00-Aileron Controls
C550GT-AD016-FU24-0213
Aileron Controls Revision: Initial Issue DATE: 01/01/2020

Description and Operation / Flight Control System

Aileron Controls
Flight Control System

27-10-00 Aileron Control

Aileron Control System.

Use the FU24-954 Maintenance Manual Chapter 27 - including the Aileron Control System, Page 7 thru 18, for
description, operation and all maintenance procedures except these tasks below.

1. Aileron Direct Pulley.

Applicable FU24 Manual section.

FU24-954 Maintenance Manual Chapter 27.
Section 2. Removals and Installations, para. (ix), page 10
Pulley Removal - Typical (Refer Figure 27.03)
Step (D)

Reason.

The C550GT aileron pulley (4), installed on the wing spar bracket, is a smaller 2-1/2 inch pulley. Two angle clips
(3) are used to replace the FU24 type cable guard pins.

Change to:

Step (D) Remove bolt, washer and nut, cable guards and pulley.

Additional Information.

Extended length aileron direct cables compensate for the C550GT Fuselage Extension. All cables are galvanised.
This change does not affect maintenance procedures. Routing and rigging is the same as the FU24-954.

Figure 27.1 Aileron Direct Pulley Installation

Page 1

MAINTENANCE MANUAL SUPPLEMENT 27-10-00-Aileron Controls
C550GT-AD016-FU24-0213
Aileron Controls Revision: Initial Issue DATE: 01/01/2020

Description and Operation / Flight Control System

2. Aileron Direct Cables.

Longer aileron direct cables compensate for the C550GT Fuselage Extension. All cables are galvanised.
Ref. Dwg. No: AD-550GT-2710-001-000

Refer to the Chapter 27 Components Changed By This STC table. See Chp. 27 Components Changed Table
This change does not effect maintenance procedures. Routing and rigging is the same as the FU24-954.

Page 2

MAINTENANCE MANUAL SUPPLEMENT 27-20-00-Rudder Controls
C550GT-AD016-FU24-0213
Rudder Controls Revision: Initial Issue DATE: 01/01/2020

Description and Operation / Rudder Control Sys.

Rudder Controls
Rudder Control Sys.

27-20-00 Rudder Control

Rudder Control System.

Extended length Rudder cables compensate for the C550GT Fuselage Extension. All cables are galvanised.
This change does not effect maintenance procedures. Routing and rigging is the same as the FU24-954.

Refer to the Components Changed By This STC table for changed part numbers.

Use the FU24-954 Maintenance Manual Chapter 27 - including the Rudder Control System, Page 19 thru 30, for
description, operation and all maintenance procedures.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 27-30-00-Stabilator Control
C550GT-AD016-FU24-0213
Stabilator Control Revision: Initial Issue DATE: 01/01/2020

Description and Operation / Stabilator & Trim

Stabilator Control
Stabilator & Trim Control

27-30-00 Stabilator Control

Description and Operation

Stabilator Control System.

Extended length Stabilator cables compensate for the C550GT Fuselage Extension. The two cables in the rear
fuselage are longer and the cockpit cable is the same length. All cables are galvanised. This change does not
affect maintenance procedures. Routing and Rigging are the same as the FU24-954.

Refer to the Chapter 27 Components Changed by This STC table for changed part numbers.

Use the FU24-954 Maintenance Manual Chapter 27 - including the Stabilator & Trim Control System, Page 31
thru 48, for description, operation and all maintenance procedures except these tasks below.

1. Stabilator Trim Control System.

FU24-954 Manual section not applicable.

FU24-954 Maintenance Manual Chapter 27.
Section 2. Trim Control System, Description and Operation.
Wiring Diagram, page 32, Figure 27.16

Reason the FU24-954 Manual section is not applicable.

Minor changes are made to the wiring and an electronic Stabilator trim Controller is installed to improve safety.

Applicable Manual section.

Refer to 27-30-01 Stabilator and Trim Control System in this supplement.
(Link) 27-30-00 Stabilator Trim Control.

Additional Information.

Applicable Electric Stabilator Trim schematic diagrams.
Ref. Dwg. No: AD-550GT-2730-001-001
Ref. Dwg. No: AD-550GT-7700-001-101

2. Trim Selector Switch and Override Relay.

FU24-954 Manual section not applicable.

FU24-954 Maintenance Manual Chapter 27.
Section 2. (iv) Trim Switch, Description and Operation.
Section 2. (v) Override Relay (Dual Only) Description and Operation.
Section 2. page 41 Trim Switch and Override Relay Illustration.
Section 3. (x) & (xi) Trim Switch Removal and Installation.
Section 3. (xii) & (xiii) Override Relay Removal and Installation.

Reason the FU24-954 Manual section is not applicable.

The Trim Switch is changed. The Override Relay is removed from the system.

Applicable Manual section.

Refer to 27-30-01 Stabilator Trim System in this supplement.
(Link) 27-30-01 Stabilator Trim System

Additional Information.

Applicable Electric Stabilator Trim schematic diagrams.
Ref. Dwg. No: AD-550GT-2730-001-001

Ref. Dwg. No: AD-550GT-7700-001-101

Page 1

MAINTENANCE MANUAL SUPPLEMENT 27-30-01-Electric Stabilator Trim
C550GT-AD016-FU24-0213
Electric Stabilator Trim Revision: Initial Issue DATE: 01/01/2020

Description and Operation / Stabilator Trim

Electric Stabilator Trim
Stabilator Trim

27-30-01 Electric Stabilator Trim

Description and Operation

Electric Stabilator Trim Control.

As the general arrangement of the C550GT stabilator trim control system is unchanged, the FU24-954
Maintenance Manual, Chapter 27, Elevator & Trim Control Systems, Section 2, Trim Control System, pg. 32-34 is
an acceptable reference.

However, STC 14/21E/5 makes improvements to the electrical system that controls the stabilator trim.
The FU24-954 system had an Override Relay in the circuit to prevent both LH and RH trim switches energising
the actuator at the same time, the action of the relay gave priority of selection to the RH trim switch.

In the cockpit on the LH side next to the stabilator control torque tube, STC 14/21E/5 removes the Override
Relay and TB5. See the FU24-954 MM Chapter 27, page 41 for reference.
In the same location, the modification adds an Electronic Trim Controller and integral connector. The controller
changes the electrical signals between the pilot trim switches and the actuator unit at the fuselage rear
bulkhead.

The new system controller gives nose-down priority when both pilot and co-pilot stick trims are used at the same
time in opposite directions.
(This is currently under review and is tagged for amendment when information received from ADL.)

The design of the controller also prevents uncontrolled stabilator trim runaway. It does this by limiting
continuous operation to 2 seconds, at that point the controller timeout stops trim operation. The stick trim switch
must be released to reset the system. The trim functions normally with continuous short activations of either
pilots stick trim switch.

The 5A ELEV TRIM circuit breaker is moved to the Centre Circuit Breaker and Switch Panel and receives 24 VDC
from the Primary Bus.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 27-30-01- Electric Stabilator Trim
C550GT-AD016-FU24-0213
Electric Stabilator Trim Revision: Initial Issue DATE: 01/01/2020

Electric Stabilator Trim Maintenance Practices / Removal and Installation
Removal and Installation
Maintenance Practices
Trim Selector Switches Removal and Installation

1. Trim Selector Switch Removal.
Ref. Dwg. No: AD-550GT-2730-001-001
Ref. Dwg. No: AD-550GT-2700-001-000
(1) Set the master Switch to OFF
(2) On the Circuit Breaker and Switch Panel, disarm the ELEV TRIM circuit breaker.
NOTE: The switch is retained in the grip by spring clips.
(3) Use the top and bottom tabs to carefully prise the switch out of the grip.
(4) Unsolder the wiring from the switch terminals.

2. Trim Selector Switch Installation.
Ref. Dwg. No: AD-550GT-2730-001-001
Ref. Dwg. No: AD-550GT-2700-001-000
(1) Solder the wires to the correct switch terminals.
(2) Carefully press the switch into the grip until the retaining clips hold it securely.
(3) Do a function check of the Stabilator Electric Trim System. (Link) Function Check
(To be added when information received from ADL covering specific use of the system fitted with
electronic runaway protection.)

WARNING: DO A DUPLICATE SAFETY INSPECTION OF THE STABILATOR TRIM CONTROL SYSTEM.

Required by NZ Civil Aviation Rules Part 43, Amendment 11 of the General Maintenance Rules.
See Rule 43.113 - Duplicate Safety Inspection of Control System.

Page 401

MAINTENANCE MANUAL SUPPLEMENT 27-50-00-Flight Controls
C550GT-AD016-FU24-0213
Flight Controls Revision: Initial Issue DATE: 01/01/2020

Description and Operation / Flap Control System

Flap Control System
Flight Controls

27-50-00 Flap Control System

Description and Operation

The pilot controls and arrangement of the Flap Control are unchanged. However, because of the fuselage
extension, modifications change the way the flap torque tube actuates. In the forward area of the cargo bay, a
transfer lever and link arms actuate the flaps. The system uses a shorter galvanised control cable that connects
the existing cockpit flap control to this lever.

Use the FU24-954 Maintenance Manual Chapter 27 - including the Flap Control System, Page 51 thru 55, for all
maintenance procedures except these tasks below.

1. Transfer Lever Assembly Removal and Installation.

See Maintenance Practices / Removal and Installation section in this supplement. See Chp. 27 Flap Cable and
Transfer Lever Assembly Removal.

2. Flap System Rigging.
See Flap System Rigging in the Adjustment & Test section in this supplement. See Chp. 27 Flap System Rigging.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 27-50-01- Flap Transfer Lever Assembly
C550GT-AD016-FU24-0213
Flap Transfer Lever Assembly Revision: Initial Issue DATE: 01/01/2020

Flap Transfer Lever Assembly Maintenance Practices / Removal & Installation
Removal & Installation
Maintenance Practices
1. Flap Cable and Transfer Lever Assembly Removal. Removal and Installation
Ref. Dwg. No: AD-550GT-2750-002-000

(1) Set the flap handle to the 0° position.
(2) Remove the forward floor panel in the cargo bay.
(3) Remove bolt, washer, nut and split pin from the cable attachment at the flap handle.
(4) Remove split pin, nut (10), washer (14), bolt (12) and spacer (7) from cable rear attachment.
(5) Attach a 3 m length of string to the cable and withdraw the cable into cockpit.
(6) Remove the cotter pin, nut (10), washers (14) and bolt (12) from transfer lever to pushrod attachment.
(7) Remove the four nuts (18), washers (13) and bolts (9) from transfer lever assembly attachment.
(8) Remove the transfer lever assembly.

Figure 27.2 Flap Control Lever Assembly

Page 1

MAINTENANCE MANUAL SUPPLEMENT 27-50-01-Flap Transfer Lever Assembly
C550GT-AD016-FU24-0213
Flap Transfer Lever Assembly Revision: Initial Issue DATE: 01/01/2020

Maintenance Practices / Removal & Installation

2. Flap Cable and Transfer Lever Assembly Installation.
Ref. Dwg. No: AD-550GT-2750-002-000
(1) Position the transfer lever assembly on the fuselage longeron.
(2) Install with the four nuts (18), washers (14) and bolts (9).
(3) Attach the pushrod (6) to the transfer lever (1) with the nut (10), washers (14) and bolt (12). Safety the nut
with the cotter pin.
(4) Pull the control cable (17) through from the cockpit.
NOTE: Use the string attached during the removal procedure.
CAUTION: MAKE SURE YOU POSITION THE CABLE IN THE PULLEY GROOVE CORRECTLY.
(5) Install the spacer (7) and attach the cable to the transfer lever. Use the nut (10), washer (14) and bolt (12).
Safety the nut with the cotter pin.

WARNING: DO A DUPLICATE SAFETY INSPECTION OF THE CONTROL SYSTEM.

Required by NZ Civil Aviation Rules Part 43, Amendment 11 of the General Maintenance Rules.
See Rule 43.113 - Duplicate Safety Inspection of Control System.

Page 2

MAINTENANCE MANUAL SUPPLEMENT 27-50-00- Flap Control Rigging
C550GT-AD016-FU24-0213
Flap Control Rigging Revision: Initial Issue DATE: 01/01/2020

Flap Control Rigging Maintenance Practices / Adjustment & Test
Adjustment & Test

Adjustment and Test

1. Flap System Rigging.
Refer to the FU24-954 Maintenance Manual, Chapter 27, page 55.

Use the rigging procedure in Para. 3 (i) except step (G)
NOTE: The large capacity hopper, introduced in this STC, changes the access to the flap cable.

(1) Open the LH door of the Fuel Component Bay.

(2) To check for the correct flap cable tension, deflect the cable by hand until a cable deflection of 1 to 1¼

inches just starts to extend the flaps.

(3) When the correct tension is set, continue with step (H) thru (J)

WARNING: DO A DUPLICATE SAFETY INSPECTION OF THE CONTROL SYSTEM.

Required by NZ Civil Aviation Rules Part 43, Amendment 11 of the General Maintenance Rules.
See Rule 43.113 - Duplicate Safety Inspection of Control System.

(4) Do step (K)
(5) Close the Fuel Component Bay door.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 28-00-00 - Fuel System DATE: 01/01/2020
Revision: Initial Issue Fuel System
C550GT-AD016-FU24-0213

Chapter 28
Title Page

Chapter 28
Fuel System

Chapter 28 Fuel System

Title Page

MAINTENANCE MANUAL SUPPLEMENT 28-00-00 - Fuel System DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Fuel System
Chapter Content

Chapter Content
Fuel System

Chapter Contents

Chapter 28 Fuel System

Applicable Section Guide

Description and Operation
> Fuel System Description.
> Fuel System Operation.

Components Changed By This STC

Troubleshooting
> Troubleshooting Table.
28-10-00 Fuel Storage System
Servicing
> Fuel Tank - Draining.
> Fuel Sampling and Testing.
> Fuel Tank Ventilation.
Maintenance Practices
Removal and Installation
28-10-01 Leading Edge Fuel Tanks
> Inboard LE Fuel Tank Removal.
> Inboard LE Fuel Tank Installation.
> Outboard Fuel Tank Removal.
> Outboard Fuel Tank Installation.
Adjustment and Test
> LE Fuel Tank Pressure Test.
28-10-02 Sump Tank
> Sump Tank Removal
> Sump Tank Installation.
28-10-03 Fuel Filler Cap
Description and Operation
> Fuel Tank Filler Cap
28-10-04 Non-Return Valve
Description and Operation
> Non-Return Valves.
Replacement
> NRV Seal Replacement.
Inspection and Check
> Inspection of Inboard LE Fuel Tank Non-Return Valve (NRV).
28-20-00 Fuel Distribution System
Servicing
> Airframe Fuel Filter Servicing.
Maintenance Practices
Removal and Installation
> Fuel Boost Pump Removal.
> Fuel Boost Pump Installation.
> Fuel Shut-off Valve Installation.
> Fuel Transfer Pump Removal.
> Fuel Transfer Pump Installation.
> Fuel Flow Transducer Removal.
> Fuel Flow Transducer Installation.
Adjustment and Test
> Fuel Transfer Pump Function Check.
> Fuel Flow Test.
> Fuel Distribution Leak Test.
> Fuel Filter Switch and Bypass Valve

MAINTENANCE MANUAL SUPPLEMENT 28-00-00 - Fuel System DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Fuel System
Chapter Content

28-40-00 Fuel Quantity Indicating
Description and Operation
> Description and Operation
Troubleshooting
> Fuel Quantity Indicating System.
Maintenance Practices
Removal and Installation
> Fuel Quantity Probe Removal.
> Fuel Quantity Probe Installation.
Adjustment and Test
> Fuel Quantity Indicating Calibration

MAINTENANCE MANUAL SUPPLEMENT 28-00-00 - Manual to Use DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Manual to Use
Chapter Guide
MANUAL TO USE
Chapter Guide
Manual to Use N/A FU24-954 C550GT

Applicable Section Guide 
SECTION / SUB-SECTION

28-00-00 Fuel System 
Description and Operation

C550GT Fuel System
Troubleshooting 

Fuel System Schematic 
Troubleshooting Table
28-10-01 Leading Edge Fuel Tanks
Maintenance Practices
Fuel Tank Ventilation Procedure
Servicing

Refueling / Defueling
Fuel Sampling
Fuel Filler Cap

Removal and Installation 
Inboard LE Fuel Tank Removal 
Inboard LE Fuel Tank Installation 
Outboard LE Fuel Tank Removal 
Outboard LE Fuel Tank Installation

Adjustment and Test 
Operational Test
Functional Test
Fuel Tank Pressure Test
System Test

28-10-02 Sump Tank 

Removal and Installation
Sump Tank Removal
Sump Tank Installation

MAINTENANCE MANUAL SUPPLEMENT 28-00-00 - Manual to Use DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Manual to Use
Chapter Guide
MANUAL TO USE
Applicable Section Guide
SECTION / SUB-SECTION N/A FU24- C550GT
950/954
28-20-00 Fuel Distribution system
Maintenance Practices 

Servicing 
Airframe Fuel Filter Element 

Removal and Installation 
Fuel Boost Pump Removal 
Fuel Boost Pump Installation 
Fuel Shut-off Valve Removal 
Fuel Shut-off Valve Installation 
Fuel Transfer Pump Removal 
Fuel Transfer Pump Installation 
Fuel Flow Transducer Removal
Fuel Flow Transducer Installation
Non-Return Valve
Non-Return Valve Seal

Adjustment & Test 
Operational Test 
Fuel Flow Test 
Filter Bypass Valve and Switch Test 
Functional Test
Fuel Transfer Pump 
Fuel Leak Test 
System Test 

Inspection and Check
LE Fuel Tank Non-Return Valves

28-40-00 Fuel Quantity Indicating System
Description and Operation

C550GT Fuel System
Troubleshooting

Fuel System Schematic
MVP-50T Troubleshooting

MAINTENANCE MANUAL SUPPLEMENT 28-00-00 - Manual to Use DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Manual to Use
Chapter Guide

Applicable Section Guide MANUAL TO USE
SECTION / SUB-SECTION N/A FU24- C550GT

28-40-00 Fuel Quantity Indicating System Cont’d 950/954
Maintenance Practices

Removal and Installation 
Capacitive Fuel Quantity Probe Removal
Capacitive Fuel Quantity Probe Installation

Adjustment and Test 
Operational Test
Functional Test
System Test
Fuel Quantity System Calibration Check

MAINTENANCE MANUAL SUPPLEMENT 28-00-00-Fuel System Description
C550GT-AD016-FU24-0213
Fuel System Description Revision: Initial Issue DATE: 01/01/2020

Description and Operation / Fuel System

Fuel System Description
Fuel System

Description and Operation

Fuel System Description.

The Crusader 550GT Fuel System is completely different from the FU24A-954 system. The systems design
automatically delivers fuel at constant pressure to the PT6A-15AG Gas Turbine's engine driven pump.

The wing centre section has four separately removable Leading Edge (LE) Fuel Tanks. Each tank has an
aerodynamic flush filler cap and a quantity probe access cover on the top surface. On the bottom surface, at
each end of each fuel tank is a fuel sample drain. The C550GT has a total of ten fuel drain valves.

The L and R Inboard are the Primary tanks and L and R Outboard are the Secondary tanks. Fuel gravity flows
from the secondary tanks into the primary tanks past a coarse screen through the main-supply flexible hoses.
Non-Return Valves (NRV) at the inlet in each Primary Tank prevent reverse-flow.

In addition to the gravity flow, each side has an electric fuel pump that separately and continuously transfers fuel
through an inline filter from the outboard to the inboard tanks. These pumps energise when the electrical system
master switch is set to ON. The system design will automatically empty the Secondary (outboard) tanks first.
The NRV's in the Primary (inboard) tanks prevent main-supply reverse flow back into the Secondary tanks.
It is important not to fly the aircraft with fuel in the outboard tanks unless the inboard tanks are full.

Vent lines interconnect the Primary and Secondary tanks on each side. Each primary tank vent line then connects
to the fuel tank venting system in the fuel component bay, aft of the cockpit rear-bulkhead. The component bay
has access through a removable belly panel. The belly-panel has a quick-release hatch on the R side.

The Primary Tanks (L and R inboard) have flexible fuel-supply hoses that gravity flow fuel to the Sump Tank. This
20-litre stainless steel tank is in the fuel component bay. The sump tank contains a submerged centrifugal boost
pump that has an integral inlet screen. The boost pump attaches to a baseplate which bolts to the flange on the
bottom of the Sump Tank.

A flexible fuel line supplies pressurised fuel from the boost pump to the shut-off valve in the fuel component bay.
A tee-handle in the cockpit controls the shut-off valve through a push/pull cable. This valve supplies fuel through
a rigid line directly to the Airframe Fuel Filter installed on the right-front bulkhead of the fuel bay.

The Airframe Fuel Filter assembly has a valve that will by-pass fuel if the paper-element type filter becomes
blocked. Before this occurs, a filter impending by-pass switch installed in the top housing, will illuminate the
FUEL FLTR annunciator on the Engine Monitor Panel. There is a manual press-to-test button on the switch
housing to test the continuity of the electrical circuit. You can access the filter and drain valve through the right
belly-panel hatch.

The Airframe Fuel System supplies pressurised fuel from the airframe fuel filter through the primary fuel line
directly to the engine fuel system. Fuel purged from the engine Fuel Control Unit returns to the vent system and
then to the Sump Tank. These two rigid fuel lines attach along the right-side cockpit floor structure below the
pilot’s seat.

There is a fuel flow transducer in the fuel supply line, aft of the instrument panel frame. This transducer
transmits flow rate signals to the Engine Data Converter (EDC). The EDC converts the signal to serial data which
displays on the F. FLOW Vertical Strip Gauge on the Engine Monitor Panel.

The modified inlet fitting of the Fuel/Oil Heater has a hose that supplies pressure to a switch and a sensor on the
L side of the engine bay firewall.
The output signal of the sensor electrically connects to the EDC input. The EDC converts the signal to serial data
which displays pressure on the FUEL P. Vertical Strip Gauge on the Engine Monitor Panel.

The output of the pressure switch connects to the EDC and signals when fuel pressure is below 2 psi. This
illuminates the FUEL P annunciator on the Engine Monitor Panel.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 28-00-00-Fuel System Description
C550GT-AD016-FU24-0213
Fuel System Description Revision: Initial Issue DATE: 01/01/2020

Description and Operation / Fuel System

Fuel System Operation.

The Master Switch is set to ON, energising the master relay and routing battery voltage to the 24 VDC primary
bus. Power through the closed contacts of the TRANSFER PUMP circuit breaker energises the fuel transfer pumps.
The transfer pumps continuously move fuel from the Secondary to the Primary tanks. Gravity fuel flow from each
Primary Tank fills the Sump Tank.

The closed contacts of the FUEL PUMP circuit breaker energise the Fuel Boost Pump in the sump tank,
pressurising the system. The boost pump continues to operate until the Master Switch is set to OFF.

If the FUEL SHUT-OFF tee-handle is in the OFF position, the FUEL P annunciator on the Engine Monitor Panel will
illuminate. Pushing the FUEL SHUT-OFF tee handle to the ON position will let pressurised fuel into the airframe
fuel filter and then to the engine fuel supply line. The sensor in the fuel line will cause the FUEL P annunciator to
go out.

The Fuel System supplies pressurised fuel through the engine's Fuel/Oil Heater to the high-pressure (HP) Fuel
Pump.

Page 2

MAINTENANCE MANUAL SUPPLEMENT 28-00-00 - Components Changed
C550GT-AD016-FU24-0213
Components Changed Revision: Initial Issue DATE: 01/01/2020

Components Changed CCBTS / Fuel System
Fuel System

Components Changed By This STC

Drawing Number Item Part Number Description / Location
28-00-00 Fuel System
AD-550GT-2800-001-000 14 AD-550GT-2810-001-000-2 Inbd Fuel Tank Assy-RH
AD-550GT-2800-001-000
AD-550GT-2800-001-000 13 AD-550GT-2810-001-000-1 Inbd Fuel Tank Assy-LH
AD-550GT-2800-001-000
AD-550GT-2820-005-000 16 AD-550GT-2810-003-000-2 Outbd Fuel Tank Assy-RH
AD-550GT-2820-002-000
AD-550GT-2810-005-000 15 AD-550GT-2810-003-000-1 Outbd Fuel Tank Assy-LH
AD-550GT-2810-001-000
AD-550GT-2810-005-000 7 FT-180 Fuel Flow Transducer
AD-550GT-2840-001-000
AD-550GT-2810-001-000 1 1743640-14 Airframe Fuel Filter
AD-550GT-2810-001-000
AD-550GT-2820-003-000 4 AD-550GT-2810-005-100 Fuel Boost Pump (2C6-2)
AD-550GT-2820-003-000
AD-550GT-2820-003-000 1 40164 Fuel Transfer Pump

5 AD-550GT-2810-005-200 Sump Tank Assembly

19 P-300C Capacitive Fuel Probe

24 CCA1600 Drain Valve

23 CAP-457-1015-12 Fuel Cap

3 8BS103 Fuel Shut-off Valve

2 038033-3-0250 Cablecraft Cable

1 08-57323-1 Bracket

Page 3

MAINTENANCE MANUAL SUPPLEMENT 28-00-00- Troubleshooting Guide
C550GT-AD016-FU24-0213
Troubleshooting Guide Revision: Initial Issue DATE: 01/01/2020

Troubleshooting / Fuel System

Troubleshooting Guide
Fuel System

Troubleshooting

Troubleshooting Table.

Table 28(b) Fuel System Troubleshooting

TROUBLE PROBABLE CAUSE ACTION

FUEL TANKS a) Transfer pump circuit breaker a) Check circuit breaker.
popped.
Inboard and Outboard LE Fuel Tank b) Transfer Pump failure. b) Check that the pump operates.
quantity is leveling out in flight. The Check that the flow rate is correct.
outboard tank fuel level does not See Chp. 28 Fuel Transfer Pump
drop to empty before fuel is used Function Check.
from the inboard tank.
c) Check transfer pumps inline filter
NOTE: THIS TABLE IS c) Transfer pump inline filter for contamination or replace filter.
UNAPPROVED CONTENT AS AT blockage.
07/05/2020 d) Do an Inspection of the LE Fuel
d) Fuel leaking back past Inboard Tank NRV. (Link 28-10-04 NRV)
NEED MORE INPUT FROM MFP Fuel Tank Non-Return Valve (NRV).
e) Make sure all vent hoses are clear.
NEED CLARIFICATION ON MVP50T e) Vent line is restricted.
CONFIGURATION

FUEL SYSTEM ANNUNCIATORS / INDICATION

No Fuel Flow indication. a) a)

b) Flow transducer failure. b) Replace transducer. See Chp. 28
c) Transducer replacement

FUEL.P Low Fuel Pressure c)
annunciator ON a) Fuel Pump circuit breaker popped. a) Check circuit breaker

Fuel Quantity Level is inaccurate b) Fuel Pump failure b) check operation of Fuel Boost
Pump
a) System requires calibration.
b) Faulty or damaged wiring to fuel a) See Chp. 28 Fuel Quantity
tank probe. Indicating System.
b) Check continuity of wiring to
quantity probes. Test probes.

LOW FUEL annunciator ON

FUEL FILTER BY-PASS / INDICATION SYSTEM

Drop in Fuel Pressure, followed a) Airframe Filter blockage a) Check the filter for contamination.
by illumination of the FUEL FLTR b) Differential switch failure See Chp. 28 Airframe Fuel Filter
differential pressure annunciator. Servicing.

c) Wiring fault. b) Do a Fuel Filter Switch and Bypass
valve operational test. See Chp. 28
Fuel Filter Switch and Bypass Valve

c) Check wiring. Check earth
connection.

Page 101

MAINTENANCE MANUAL SUPPLEMENT
C550GT-AD016-FU24-0213
Fuel System Schematic

Fuel System Schematic
Troubleshooting

28-00-00-Fuel System Schematic

Revision: Initial Issue DATE: 01/01/2020

Troubleshooting

Page 102

MAINTENANCE MANUAL SUPPLEMENT 28-10-00- Servicing
C550GT-AD016-FU24-0213
Servicing Revision: Initial Issue DATE: 01/01/2020

Servicing Maintenance Practices / Fuel System
Fuel System

28-10-00 Fuel Storage System

Servicing

1. Fuel Tank - Draining.
For information on fuel system draining, See Chp. 12 Defuelling.

2. Fuel Sampling and Testing.

Ref. Ext. Doc: New Zealand CAA Advisory Circular AC91-22
Aircraft Refuelling and Defueling - Fire Prevention and Safety Guidance (latest revision) for fuel sampling,
draining, refuelling and defuelling procedures applicable to this aircraft.

Page 301

MAINTENANCE MANUAL SUPPLEMENT 28-10-00- Ventilation Procedure
C550GT-AD016-FU24-0213
Ventilation Procedure Revision: Initial Issue DATE: 01/01/2020

Ventilation Procedure Maintenance Practices / LE Fuel Tanks
LE Fuel Tanks

1. Fuel Tank Ventilation.

WARNING: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS WHEN YOU DO WORK ON THE FUEL SYSTEM.

NOTE: If you need to repair the LE Fuel Tank, remove the tank from the aircraft. Ventilation is the same for
Inboard or Outboard tanks.

(1) Remove the LE Fuel Tank. See Chp. 28 Inboard LE Fuel Tank Removal.
(2) Remove the fuel cap.
(3) Remove the screws (20) and washers (22) from the two inspection hatch panels (17) on the rear side of the

tank.
(4) Remove the hatch covers.

NOTE: The hatch covers are installed with sealant.
(5) Drain residual fuel from the tank.

NOTE: Rotate the tank to move fuel to the drain fittings.
(6) Using a dry air source, blow compressed air into the tank.
(7) Use clean lint-free cloth soaked in Isopropyl Alcohol to clean the inside of the tank.
(8) Continue ventilating until work on the tank is complete.

CAUTION: MAKE SURE THE INSIDE OF THE TANK IS CLEAN AND DRY BEFORE YOU REASSEMBLE THE TANK.

Page 302

MAINTENANCE MANUAL SUPPLEMENT 28-10-01- LE Wing Tanks
C550GT-AD016-FU24-0213
LE Wing Tanks Revision: Initial Issue DATE: 01/01/2020

Removal & Installation Maintenance Practices / Removal & Installation
LE Wing Tanks
Maintenance Practices
1. Inboard LE Fuel Tank Removal. Removal and Installation
Ref. Dwg. No: AD-550GT-2800-001-000
28-10-01 Leading Edge Fuel Tanks

The procedure is the same for the L and R Inboard LE Tanks.
NOTE: Cap all open fittings during this procedure to prevent contamination.

WARNING: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS. MAKE SURE ALL PERSONNEL KNOW THE
DANGERS OF FUEL VAPOUR AND LEAKAGE.

CAUTION: CONNECT A GROUND CABLE TO THE AIRCRAFT TO ELIMINATE THE DANGER OF ELECTROSTATIC
DISCHARGE.

(1) Drain the fuel from the inboard LE Fuel Tank and the Sump Tank.
(2) Remove the gap strip between the inboard and the outboard tank.
(3) Disconnect the electrical loom for the quantity probe and fuel pump. Carefully remove the insulation to

access the connectors.
(4) Disconnect the flexible fuel-supply hoses.
(5) Disconnect the flexible vent system hoses.
(6) Access the Fuel Component Bay through the belly-panel maintenance hatch.
(7) Disconnect the flexible fuel-supply hoses from the inboard tank fitting.
(8) Disconnect the vent system rigid line.
(9) Remove the seven bottom tank attach screws first
(10) Support the tank, then remove the seven top attach screws.

NOTE: You need a minimum of two people for this task.
(11) Carefully remove the tank from the wing spar shear-blocks.

CAUTION: MAKE SURE YOU DO NOT DAMAGE THE VENT FITTING OR THE FUSELAGE SKIN. THERE IS
MINIMUM CLEARANCE WHERE THE VENT FITTING ENTERS THE FUSELAGE.

2. Inboard LE Fuel Tank Installation.

WARNING: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS. MAKE SURE ALL PERSONNEL KNOW THE
DANGERS OF FUEL VAPOUR AND LEAKAGE.

CAUTION: TO FUNCTION CORRECTLY, THE SHEAR BLOCKS THAT SUPPORT THE FUEL TANK HAVE MINIMUM
CLEARANCE. MAKE SURE YOU DO NOT DAMAGE THE SHEAR BLOCKS WHEN YOU INSTALL THE
TANK.

(1) Support the Fuel Tank while you carefully put the vent fitting through the opening in the fuselage skin.
NOTE: You need a minimum of two people for this task.

CAUTION: MAKE SURE YOU DO NOT DAMAGE THE VENT FITTING OR THE FUSELAGE SKIN. THERE IS
MINIMUM CLEARANCE WHERE THE VENT FITTING ENTERS THE FUSELAGE.

(2) Position the fuel tank on the shear blocks and align the screw holes.
(3) Install the seven top attach screws, but do not tighten the screws fully in this step.
(4) Install the seven bottom attach screws.
(5) Tighten all the screws to the standard torque. Refer to Chp 20 See Chp. 20 Standard Fastener Torques
(6) At the area between the inboard and the outboard tank, connect the electrical loom to the quantity probe

and fuel pump connectors.

Page 401

MAINTENANCE MANUAL SUPPLEMENT 28-10-01-LE Wing Tanks
C550GT-AD016-FU24-0213
LE Wing Tanks Revision: Initial Issue DATE: 01/01/2020

Maintenance Practices / Removal & Installation

CAUTION: INSULATE THE CONNECTION. DAMAGE WILL OCCUR IF MOISTURE GETS INTO THE
CONNECTORS.

CAUTION: IN THE NEXT STEP, MAKE SURE THE HOSES ARE CLEAN AND NOT DAMAGED. REMOVE ALL CAPS.
(7) Connect the flexible fuel-supply hoses.
(8) Connect the flexible vent system hoses.

NOTE: Do not install the gap strip at this time.
(9) Access the Fuel Component Bay through the belly-panel maintenance hatch.

CAUTION: IN THE NEXT STEP, MAKE SURE THE HOSES ARE CLEAN AND NOT DAMAGED. REMOVE ALL CAPS.
(10) Connect the flexible fuel-supply hoses to the inboard tank fitting.
(11) Connect the vent system rigid line.

CAUTION: MAKE SURE YOU DO A FUEL QUANTITY INDICATING SYSTEM FUNCTION CHECK.
NOTE: Refer to Electronics International Inc. MVP-50T Instructions for Continued Airworthiness Doc.
06201101. These instructions provide information to correctly function check the C550GT Fuel
Quantity Indicating System.

(link) E.I.Inc MVP-50T ICA

(12) Make sure there is sufficient fuel in the Fuel Tanks.
(13) Do a Fuel Distribution System Leak Test for Non-pressurised components. See Chp. 28 Fuel Distribution

Leak Test.
(14) Install the gap strip.

3. Outboard Fuel Tank Removal.

The procedure is the same for the L and R Outboard LE Tanks.

NOTE: Cap all open fittings during this procedure to prevent contamination.

WARNING: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS. MAKE SURE ALL PERSONNEL KNOW THE
DANGERS OF FUEL VAPOUR AND LEAKAGE.

CAUTION: CONNECT A GROUND CABLE TO THE AIRCRAFT TO ELIMINATE THE DANGER OF ELECTROSTATIC
DISCHARGE.

(1) Drain Fuel from the outboard tank.
(2) Remove the gap strip between the inboard and the outboard tank.
(3) Disconnect the flexible fuel-supply hoses.
(4) Disconnect the flexible vent system hoses.
(5) Remove the gap strip at the outboard end of the tank.
(6) Disconnect the electrical loom for the quantity probe.

NOTE: Carefully remove the insulation to access the connectors.Remove the five bottom tank attach screws
first

(7) Support the tank, then remove the five top attach screws.
NOTE: Use a minimum of two personnel for this task.

(8) Carefully remove the tank from the wing spar.

4. Outboard Fuel Tank Installation.
The procedure is the same for the L and R Outboard LE Tanks.

Page 402

MAINTENANCE MANUAL SUPPLEMENT 28-10-01-LE Wing Tanks
C550GT-AD016-FU24-0213
LE Wing Tanks Revision: Initial Issue DATE: 01/01/2020

Maintenance Practices / Removal & Installation

WARNING: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS. MAKE SURE ALL PERSONNEL KNOW THE
DANGERS OF FUEL VAPOUR AND LEAKAGE

CAUTION: TO FUNCTION CORRECTLY, THE SHEAR BLOCKS THAT SUPPORT THE FUEL TANK HAVE MINIMUM
CLEARANCE. MAKE SURE YOU DO NOT DAMAGE THE SHEAR BLOCKS WHEN YOU INSTALL THE
TANK.

(1) Support the Fuel Tank while you carefully position it onto the wing spar shear-blocks.
NOTE: You need a minimum of two people for this task.

(2) Install the five top attach screws, but do not tighten the screws fully in this step.
(3) Install the five bottom attach screws.
(4) Tighten all the screws to the standard torque. Refer to Chp 20 Standard Torques See Chp. 20 Standard

Fastener Torques
(5) At the outboard end of the tank, connect the electrical loom for the quantity probe.

NOTE: Insulate the connection. Damage will occur if moisture gets into the connectors.
NOTE: Do not install the gap strip at this time.
CAUTION: IN THE NEXT STEP, MAKE SURE THE HOSES ARE CLEAN AND NOT DAMAGED. REMOVE ALL CAPS.
(6) At the area between the inboard and the outboard tank:
(7) Connect the flexible fuel-supply hoses.
(8) Connect the flexible vent system hoses.
NOTE: Do not install the gap strip at this time.
CAUTION: MAKE SURE YOU DO A FUEL QUANTITY INDICATING SYSTEM FUNCTION CHECK.
NOTE: Refer to Electronics International Inc. MVP-50T Instructions for Continued Airworthiness Doc.

06201101. These instructions provide information to correctly function check the C550GT Fuel
Quantity Indicating System. (link) E.I. Inc. MVP-50T ICA
(9) Make sure there is sufficient fuel in the Fuel Tanks.
(10) Do a Fuel Distribution System Leak Test for Non-pressurised components. See Chp. 28 Fuel Distribution
Leak Test.
(11) Install the gap strips.

Page 403

MAINTENANCE MANUAL SUPPLEMENT 28-10-01- LE Fuel Tanks
C550GT-AD016-FU24-0213
LE Fuel Tanks Revision: Initial Issue DATE: 01/01/2020

Adjustment & Test Maintenance Practices / Adjustment & Test
LE Fuel Tanks

Adjustment and Test

1. LE Fuel Tank Pressure Test.
CAUTION: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS.
Do this Pressure Test to find a leak-point in the tank or after leakage or damage repairs.

WARNING: MAKE SURE THE FUEL TANK TEST PRESSURE ALWAYS REMAINS BELOW 1.5 PSI. HIGH
PRESSURE WILL DAMAGE THE TANK STRUCTURE AND CAN CAUSE PERSONAL INJURY.

Test Equipment.
(1) Regulated dry air supply that includes a safety device to make sure the pressure inside the tank is not more

than 1.5 psi.
(2) Pressure gauge (0-5 psi) with fittings compatible with the fuel tank vent fitting.
(3) Caps to seal the tank fittings.
(4) A solution of 75% water and 25% weak detergent.

Test Procedure.
Drain and ventilate the fuel tank. Refer to Fuel Tank Ventilation Procedure, See Chp. 28 Fuel Tank Ventilation.
CAUTION: MAKE SURE TO CORRECTLY VENTILATE THE TANK. FUEL VAPOUR CAN CAUSE EXPLOSIVE FIRE

AND INJURY.

(1) Install the 0-5 psi pressure gauge to the vent fitting.
(2) Connect a regulated dry air supply to a compatible tank fitting.
(3) Cap all remaining tank fittings.
(4) Open the regulated air supply valve and increase the air pressure to 1 psi.

NOTE: Use the vent fitting pressure gauge to carefully monitor the tanks internal pressure.
(5) Shut off the regulated air supply to hold the tank pressure at 1 psi.
(6) Apply the detergent solution to the tank joints, rivets, inspection panels and fittings.
(7) During a period of 15 minutes, examine the tank for air leakage and monitor the vent fitting pressure gauge.

Result.
If there is no visible air leakage and the internal pressure of the fuel tank does not drop, the test is complete.
Post Test Procedure.
(1) Release the pressure from the tank.

(2) Remove the test caps and fittings.

(3) Clean all signs of the detergent solution from the tank surfaces.

Page 501

MAINTENANCE MANUAL SUPPLEMENT 28-10-02- Sump Tank
C550GT-AD016-FU24-0213
Sump Tank Revision: Initial Issue DATE: 01/01/2020

Removal & Installation Maintenance Practices / Removal & Installation
Sump Tank

28-10-02 Sump Tank

1. Sump Tank Removal
Ref. Dwg. No: AD-550GT-2810-005-000

WARNING: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS. MAKE SURE ALL PERSONNEL KNOW THE
DANGERS OF FUEL VAPOUR AND LEAKAGE.

CAUTION: CONNECT A GROUND CABLE TO THE AIRCRAFT TO ELIMINATE THE DANGER OF ELECTROSTATIC
DISCHARGE.

(1) Set the master switch to OFF.
(2) Remove the belly-panel to access the Fuel Component Bay. See Chp. 12 Access Panel Diagram.

NOTE: Cap all open fittings during this procedure to prevent contamination.
(3) Drain the fuel from the inboard LE Fuel Tanks and the Sump Tank.
(4) Remove the P-clamps that attach the pump wiring to the supply hose.
(5) Disconnect the fuel pump electrical loom.

NOTE: Carefully remove the insulation to access the connectors.
(6) Disconnect the fuel supply hose at the Boost Pump outlet fitting.
(7) Disconnect the two flexible Inboard Tank fuel-supply hoses from the Sump Tank.
(8) At the top of the tank, disconnect the rigid line to the vent system.
(9) Remove the five screws, washers and nuts from each side mount bracket.
(10) Remove the Sump Tank.
(11) Remove the Fuel Boost Pump assembly. See Chp. 28 Fuel Boost Pump Removal.

2. Sump Tank Installation.
Ref. Dwg. No: AD-550GT-2810-005-000
(1) Install the Fuel Boost Pump assembly. See Chp. 28 Fuel Boost Pump Installation.
(2) Put the Sump Tank in position on its attach brackets (2).
(3) Attach the tank with the screws (8), washers (11) and nuts (13).
(4) Connect the rigid vent line to the top of the tank.
(5) Connect the two flexible Inboard Tank fuel-supply hoses to the tank fittings.
(6) Connect the fuel supply hose to the Boost Pump outlet fitting.
(7) If removed, connect the fuel supply hose to the shut-off valve.
(8) Connect the pump wiring loom.
NOTE: Insulate the connection. Damage will occur if moisture gets into the connectors.
(9) Secure the Boost Pump wiring loom to the fuel supply hose with the P-clamps.
(10) Do a Fuel Distribution System Leak Test. See Chp. 28 Fuel Distribution Leak Test.
(11) Do a Fuel Flow Test. See Chp. 28 Fuel Flow Test.
Install the Fuel Component Bay belly-panel. Refer to Chapter 12.

Page 401

MAINTENANCE MANUAL SUPPLEMENT 28-10-03-Filler Cap
C550GT-AD016-FU24-0213
Filler Cap Revision: Initial Issue DATE: 01/01/2020

Description and Operation / Fuel System

Filler Cap
Fuel System

28-10-03 Fuel Filler Cap

Description and Operation

Fuel Tank Filler Cap

The C550GT uses the Parker Aerospace lightning-safe gravity fuel filler cap. The caps are used to lock, seal, and
act as an identifier for the gravity fill port of all LE Fuel Tanks.
The gravity fuel filler caps are three inches in diameter and are the indexing type. To fuel the aircraft, manually
actuate the cap by lifting and turning the handle, which vents the fuel tank. The cap is then removed from its
mating adapter, allowing the aircraft to be refuelled. The cap remains attached to the aircraft by a lanyard. Once
refuelling is complete, the cap is inserted back into the adapter and the handle is actuated back to a closed
position, which effectively reseals the gravity fill refuel port.

Parker Aerospace product data can be accessed at the www.parker.com website.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 28-10-04-Non-Return Valve Description
C550GT-AD016-FU24-0213
Non-Return Valve Description Revision: Initial Issue DATE: 01/01/2020

Non-Return Valve Description Description and Operation / Fuel System
Fuel System

28-10-04 Non-Return Valve

Description and Operation

Non-Return Valves.

Two hinged flap-type Non-Return Valves (NRV) in the system prevent fuel feedback into the outboard tanks from
the inboard tanks. The valves are inside the Inboard LE Fuel Tank in the bottom of the outboard rib.

The NRV gives unrestricted gravity feed from the outboard wing tank to the inboard tank and prevents the flow
of fuel from the inboard tank back into the outboard tank.

Refer to the Fuel System Schematic to see the two NRV positions in the system. See Chp. 28 Fuel System
Schematic

Figure 28.3 Inbd. LE Fuel Tank NRV.
Page 1

MAINTENANCE MANUAL SUPPLEMENT 28-10-04- Non-Return Valve Seal
C550GT-AD016-FU24-0213
Non-Return Valve Seal Revision: Initial Issue DATE: 01/01/2020

Replacement Maintenance Practices / Replacement
Non-Return Valve Seal
Replacement
1. NRV Seal Replacement.
Ref. Dwg. No: AD-550GT-2810-001-112
Ref. Dwg. No: AD-550GT-2810-001-000

NOTE: To replace a damaged NRV Buna-N seal, you must remove the LE Fuel Tank.
(1) Drain the fuel. See Chp. 12 Defuelling.
(2) Remove the Inboard LE Fuel Tank. See Chp. 28 Inboard LE Fuel Tank Removal.
(3) Ventilate the Fuel Tank. See Chp. 28 Fuel Tank Ventilation.
(4) Remove the nut (6) washer (8) and screw (7) from the NRV flap.
(5) Remove the damaged seal (2) and discard it.
(6) Install the replacement seal (2) with the screw (7), washer (8) and nut (6).
(7) Examine the NRV visually to confirm the seal seats correctly on the bulkhead fitting. Check that the flap

moves freely.
(8) Reinstall the fuel tank access panels.

NOTE: Seal the access panels using PR-1422 A2 sealant (or equivalent AMS-S-8802 sealant) in accordance
with adhesive manufacturer’s instructions.

(9) Install the LE Fuel Tank. See Chp. 28 Inboard LE Fuel Tank Installation.

Figure 28.4 NRV seal replacement

Page 201

MAINTENANCE MANUAL SUPPLEMENT 28-10-04- Inboard LE Fuel Tank NRV
C550GT-AD016-FU24-0213
Inboard LE Fuel Tank NRV Revision: Initial Issue DATE: 01/01/2020

Inspection and Check Maintenance Practices / Inspection and Check
Inboard LE Fuel Tank NRV

Inspection and Check

1. Inspection of Inboard LE Fuel Tank Non-Return Valve (NRV).
Ref. Dwg. No: AD-550GT-2810-001-110
Ref. Dwg. No: AD-550GT-2810-001-112

Do this inspection if you suspect a malfunction of the NRV.
(1) Drain the fuel. (Link) See Chapter 12 Defueling.
(2) Remove the outboard fuel drain fitting from the bottom of the Inboard LE Fuel Tank.
(3) Remove the fuel filler cap.
(4) Fabricate a tool from a suitable length piece of aluminum welding wire, bend a hook in one end.

NOTE: You will need 2 personnel for the next step.
(5) Pass the wire through the open fuel filler and the tank rib (4). Apply a light force up to lift the NRV seal flap

(1) to the full range of travel.

CAUTION: USE A LIGHT FORCE. YOU CAN DAMAGE THE NRV FLAP. MAKE SURE YOU DO NOT SCRATCH ANY
PART OF THE INSIDE OF THE FUEL TANK.

(6) Make sure the NRV flap is free to move with no resistance.
(7) While carefully holding the NRV Flap up, look through the drain valve hole and examine the face of the seal.

NOTE: Use a bright light. You can also use a borescope.
(8) Check the Buna-N seal face for contamination or visible damage.
(9) Check the face of the inlet fitting for damage.
(10) If you find damage, remove and replace the faulty part. (Link) NRV Seal Replacement.
(11) Reinstall the fuel drain valve.
(12) Refuel the aircraft. (Link) See Chapter 12-10-01 Refueling

Figure 28.5 NRV Seal Inspection

Page 601

MAINTENANCE MANUAL SUPPLEMENT 28-20-00- Airframe Fuel Filter
C550GT-AD016-FU24-0213
Airframe Fuel Filter Revision: Initial Issue DATE: 01/01/2020

Servicing Maintenance Practices / Servicing
Airframe Fuel Filter

28-20-00 Fuel Distribution System

Servicing

1. Airframe Fuel Filter Servicing.
See Figure 28.6

WARNING: OBEY ALL FIRE AND SAFETY PRECAUTIONS WHEN YOU DO WORK ON THE FUEL SYSTEM.

(1) Set the Master Switch to OFF.
(2) Make sure the Fuel Shut-off Valve tee-handle is in the OFF position.

NOTE: Placard the tee-handle. DO NOT OPERATE.
(3) Open the RH side access hatch to the Fuel Component bay.
(4) Remove the lockwire from the bowl retainer nut.
(5) Put a clean container under the filter bowl.
(6) Open the filter bowl drain valve.

NOTE: Fuel will not drain until the bowl nut is loose.
(7) Loosen the retainer nut and lower the bowl and filter-element clear of the hatch.
(8) Remove and discard the filter-element.

NOTE: The filter-element is not cleanable.
(9) Remove and discard the filter head O-ring.
(10) Remove and discard the in-head gasket and the nylon element retainer gasket.
(11) Make sure the filter bowl is clean
(12) Install replacement filter kit P/N 1743645-02.

a. Install the new gasket in the nylon element retainer with the concave side against the filter-element.
b. Install the new in-head gasket with the concave side against the filter-element.
c. Install the new O-ring in the filter head.

NOTE: Lubricate the head to bowl O-ring with turbine engine oil.
d. Install the new filter element.
(13) Carefully position the filter bowl and tighten the bowl retainer nut.
(14) Torque the retainer nut to 25-50 lbs in. and safety it with lockwire.
(15) Remove the placard from the fuel shut-off tee-handle.
(16) Set the master switch to ON.
(17) Operate the fuel boost pump. Open fuel filter bowl drain until to purge all air.
(18) Do a fuel leak check.
(19) Test the Filter By-pass warning system.

Page 301

MAINTENANCE MANUAL SUPPLEMENT 28-20-00-Airframe Fuel Filter
C550GT-AD016-FU24-0213
Airframe Fuel Filter Revision: Initial Issue DATE: 01/01/2020

Maintenance Practices / Servicing

Figure 28.6 Airframe Fuel Filter

Page 302

MAINTENANCE MANUAL SUPPLEMENT 28-20-01- Fuel Boost Pump
C550GT-AD016-FU24-0213
Fuel Boost Pump Revision: Initial Issue DATE: 01/01/2020

Removal & Installation Maintenance Practices / Removal & Installation
Fuel Boost Pump

Maintenance Practices
Removal and Installation

1. Fuel Boost Pump Removal.
Ref. Dwg. No: AD-550GT-2810-005-000

WARNING: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS. MAKE SURE ALL PERSONNEL KNOW THE
DANGERS OF FUEL VAPOUR AND LEAKAGE.

CAUTION: CONNECT A GROUND CABLE TO THE AIRCRAFT TO ELIMINATE THE DANGER OF ELECTROSTATIC
DISCHARGE.

(1) Set the master switch to OFF.
(2) Remove the belly-panel to access the Fuel Component Bay. See Chp. 12 Access Panel Diagram.
(3) Drain the fuel from the inboard LE Fuel Tanks and the Sump Tank.
(4) Remove the P-clamps that attach the pump wiring to the supply hose.
(5) Disconnect the fuel pump electrical loom.

NOTE: Carefully remove the insulation to access the connectors.
(6) Disconnect the fuel supply hose at the Boost Pump outlet fitting.
(7) Cut and remove the lockwire, then remove the bolts and washers that attach the pump base plate to the

Sump Tank.
(8) Remove the pump assembly from the Sump Tank.

NOTE: Remove the O-ring seal with the pump assembly.
(9) Remove the four nuts and washers that attach the pump to the base plate.
(10) Carefully break the sealant joint and remove the pump from the base plate.

2. Fuel Boost Pump Installation.
Ref. Dwg. No: AD-550GT-2810-005-000

WARNING: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS. MAKE SURE ALL PERSONNEL KNOW THE
DANGERS OF FUEL VAPOUR AND LEAKAGE.

(1) Put the pump wiring through the hole in the base plate.
(2) Apply a small bead of fuel compatible sealant to the mating face of the pump.
(3) Attach the pump to the base plate with the four nuts and washers.
(4) Install a new O-ring to the base plate of the pump assembly.
(5) Attach the pump assembly to the flange on the Sump Tank with the bolts and washers.
(6) Safety the bolts with lockwire.
(7) Connect the fuel supply hose at the Boost Pump outlet fitting.
(8) If removed, connect the fuel supply hose to the shut-off valve.
(9) Connect the pump wiring loom.

NOTE: Insulate the connection. Damage will occur if moisture gets into the connectors.
(10) Secure the Boost Pump wiring loom to the fuel supply hose with the P-clamps.
(11) Do a Fuel Distribution System Leak Test. See Chp. 28 Fuel Distribution Leak Test.
(12) Do a Fuel Flow Test. See Chp. 28 Fuel Flow Test.
(13) Install the Fuel Component Bay belly-panel. Refer to Chapter 12. See Chp. 12 Access Panel Diagram.

Page 401

MAINTENANCE MANUAL SUPPLEMENT 28-20-02- Fuel Shut-Off Valve
C550GT-AD016-FU24-0213
Fuel Shut-Off Valve Revision: Initial Issue DATE: 01/01/2020

Removal & Installation Maintenance Practices / Removal & Installation
Fuel Shut-Off Valve

1. Fuel Shut-off Valve Removal.
Ref. Dwg. No: AD-550GT-2820-003-000.

WARNING: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS. MAKE SURE ALL PERSONNEL KNOW THE
DANGERS OF FUEL VAPOUR AND LEAKAGE.

CAUTION: CONNECT A GROUND CABLE TO THE AIRCRAFT TO ELIMINATE THE DANGER OF ELECTROSTATIC
DISCHARGE.

(1) Set the master switch to OFF.
(2) Remove the belly-panel to access the Fuel Component Bay. Refer to Chapter 12. See Chp. 12 Access Panel

Diagram.

CAUTION: CAP ALL OPEN FITTINGS DURING THIS PROCEDURE TO PREVENT LEAKAGE AND
CONTAMINATION.

(3) Drain the fuel from the inboard LE Fuel Tanks and the Sump Tank.
(4) Disconnect the fuel supply hose at inlet to the Fuel Shut-off Valve.
(5) Disconnect the rigid fuel line at the outlet to the Fuel Shut-off Valve.
(6) Remove the cotter pin (18), castellated nut (9), washers (13) and bolt (6) from the cable rod end (14).

NOTE: Make sure you keep the correct position of the spacer washers on reassembly.
(7) Remove the three P-clamps (17) that attach the valve to the bracket.
(8) Remove the Fuel Shut-off Valve assembly.

NOTE: In the next step, mark the position of the lever-plate before removal.
(9) Remove the two bolts (7) washers (13) and nuts (15), then remove the lever (4).

2. Fuel Shut-off Valve Installation.
Ref. Dwg. No: AD-550GT-2820-003-000

WARNING: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS. MAKE SURE ALL PERSONNEL KNOW THE
DANGERS OF FUEL VAPOUR AND LEAKAGE.

CAUTION: CONNECT A GROUND CABLE TO THE AIRCRAFT TO ELIMINATE THE DANGER OF ELECTROSTATIC
DISCHARGE.

(1) Set the master switch to OFF.
(2) Remove the belly-panel to access the Fuel Component Bay. Refer to Chapter 12. See Chp. 12 Access Panel

Diagram.
(3) If removed, attach the lever-plate to the Shut-off Valve with the bolts (7), washers (13) and nuts (15).

NOTE: Make sure to position the lever plate in the correct angular position on the valve.
(4) Position the Shut-off Valve on the bracket and attach it with the P-clamps (17).
(5) Connect the rigid fuel line (21) to the outlet fitting of the valve.
(6) Connect the fuel supply hose to the inlet fitting of the valve.
(7) Position the cable rod end (14) on to the lever-plate and attach with the bolt (6), washers (13) and nut (9).

NOTE: Make sure you keep the correct position of the spacer washers, and the bolt head is at the bottom.
(8) Safety the castellated nut (9) with the cotter pin (18).
(9) Operate the shut-off valve to make sure the clevis attach bolt does not touch the P-clamp. Make sure the

cable and valve operate smoothly.
(10) Do a Fuel Distribution System Leak Test. See Chp. 28 Fuel Distribution Leak Test.
(11) Do a Fuel Flow Test. See Chp. 28 Fuel Flow Test.

Page 402

MAINTENANCE MANUAL SUPPLEMENT 28-20-03- Fuel Transfer Pump
C550GT-AD016-FU24-0213
Fuel Transfer Pump Revision: Initial Issue DATE: 01/01/2020

Removal & Installation Maintenance Practices / Removal & Installation
Fuel Transfer Pump

1. Fuel Transfer Pump Removal.
Ref. Dwg. No: AD-550GT-2800-001-000
Ref. Dwg. No: AD-550GT-2810-001-100
Ref. Dwg. No: AD-550GT-5740-002-000

WARNING: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS. MAKE SURE ALL PERSONNEL KNOW THE
DANGERS OF FUEL VAPOUR AND LEAKAGE.

NOTE: To prevent too much fuel leakage, make sure the Outboard LE Tank is low or is empty of fuel.
(1) Remove the Wing LE gap strip between the Inboard and Outboard LE Tanks.
(2) Disconnect the fuel pump electrical loom.

NOTE: Carefully remove the insulation to access the connectors.
(3) Remove the hose clamps (26) from the inlet and outlet hoses (27) of the Facet Fuel Transfer Pump.
(4) Remove the transfer hoses from the pump fittings.

NOTE: Cap all open fittings during this procedure to prevent contamination and leakage.
(5) Support the transfer pump and remove the two screws (7).

NOTE: One of the screws holds the electrical ground wire terminal.
(6) Remove the transfer pump.

Figure 28.7 Fuel Transfer Pump

2. Fuel Transfer Pump Installation.
Ref. Dwg. No: AD-550GT-2800-001-000
Ref. Dwg. No: AD-550GT-2810-001-100
Ref. Dwg. No: AD-550GT-5740-002-000
WARNING: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS. MAKE SURE ALL PERSONNEL KNOW THE
DANGERS OF FUEL VAPOUR AND LEAKAGE.

Page 403

MAINTENANCE MANUAL SUPPLEMENT 28-20-03-Fuel Transfer Pump
C550GT-AD016-FU24-0213
Fuel Transfer Pump Revision: Initial Issue DATE: 01/01/2020

Maintenance Practices / Removal & Installation

(1) Support the pump in position and install the two screws (7).
NOTE: One of the screws holds the ground wire terminal.

(2) Attach the hose to the transfer pump inlet fitting and tighten the clamp (26)
NOTE: Do not connect the hose to the pump outlet fitting at this time.

(3) Connect the pump wiring loom.
NOTE: Insulate the connection. Damage will occur if moisture gets into the connectors.

(4) Do a Transfer Pump Function Check. See Chp. 28 Fuel Transfer Pump Function Check.
(5) Do a Fuel Distribution System leak Test. See Chp. 28 Fuel Distribution Leak Test.
(6) Install the Wing LE gap strip.

Page 404

MAINTENANCE MANUAL SUPPLEMENT 28-20-04- Fuel Flow Transducer
C550GT-AD016-FU24-0213
Fuel Flow Transducer Revision: Initial Issue DATE: 01/01/2020

Removal & Installation Maintenance Practices / Removal & Installation
Fuel Flow Transducer

1. Fuel Flow Transducer Removal.
Ref. Dwg. No: AD-550GT-2820-005-000

WARNING: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS. MAKE SURE ALL PERSONNEL KNOW THE
DANGERS OF FUEL VAPOUR AND LEAKAGE.

CAUTION: CONNECT A GROUND CABLE TO THE AIRCRAFT TO ELIMINATE THE DANGER OF ELECTROSTATIC
DISCHARGE.

(1) Set the master switch to OFF.
(2) Make sure the Fuel Shut-off Valve tee-handle is in the OFF position.

NOTE: Placard the tee-handle. DO NOT OPERATE.
(3) Drain the fuel filter.
(4) Disconnect the transducer electrical loom.

NOTE: Carefully remove the insulation to access the connectors.
(5) If necessary, remove the P-clamps from the rigid lines.
(6) Disconnect the fuel inlet and outlet rigid lines from the transducer fittings.

NOTE: Cap all open fittings during this procedure to prevent contamination.
(7) Remove nuts (9), washers (6) and bolts (4).
(8) Remove the transducer.
(9) Remove the fuel inlet and outlet fittings.

2. Fuel Flow Transducer Installation.
Ref. Dwg. No: AD-550GT-2820-005-000
(1) Install the fuel inlet and outlet fittings into the transducer.
(2) Position the transducer on the bracket (1).
(3) Install with bolts (4), washers (6) and nuts (9).
(4) Connect inlet and outlet rigid lines to the transducer fittings.
(5) If removed, install the P-clamps to the rigid lines.
(6) Connect the electrical loom to the transducer.
NOTE: Insulate the connection. Damage will occur if moisture gets into the connectors.
(7) Remove the temporary Tee Handle placard installed during the removal procedure.
(8) Set the Master Switch to ON.
(9) Set the Fuel Shut-off Valve tee-handle to the ON position.
(10) Do a Fuel Distribution System Leak Test. See Chp. 28 Fuel Distribution Leak Test.
(11) Do a Fuel Flow Test. See Chp. 28 Fuel Flow Test.

CAUTION: MAKE SURE YOU DO A FUEL FLOW INDICATING SYSTEM FUNCTION CHECK.
NOTE: Ground run the engine to Idle speed and check the Fuel Flow (Wf) against known parameters. Refer
to the P&WC Maintenance Manual, Chp. 71-00-00 Adjustment and Test.

Ref. Ext. Doc: P&WC Maintenance Manual, Turboprop Gas Turbine Engine, Model PT6A-15AG Manual Part No.
3030442 (latest revision).

Page 404

MAINTENANCE MANUAL SUPPLEMENT 28-20-00- Transfer Pump Test
C550GT-AD016-FU24-0213
Transfer Pump Test Revision: Initial Issue DATE: 01/01/2020

Transfer Pump Test Maintenance Practices / Adjustment & Test
Adjustment & Test
Adjustment and Test
1. Fuel Transfer Pump Function Check.

Function Test.
a. Connect the aircraft electrical system to a Ground Power Unit (GPU) during the test.
NOTE: Make sure you install a clean filter element in the Swagelok Tee-Type Filter Assembly (47) for the
test. If the average period for the specified fuel quantity is more than the maximum, change the
filter element and do the test again.

b. Connect a hose to the outlet of the Transfer Pump.
c. Put the free end of the hose in a container positioned at the same height as the inlet to the LE Inboard Fuel

Tank.

WARNING: MAKE SURE PERSONNEL ARE AWARE OF THE DANGERS OF FUEL IN AN OPEN CONTAINER.

d. Connect the aircraft to a Ground Power Unit (GPU).
NOTE: Two persons are necessary to do this procedure. One person in the cockpit and one person outside at
the fuel container.

e. Make sure the transfer pump circuit breaker is IN.
f. Set the Master Switch to ON.

NOTE: This will energise the Transfer Pump.

g. Let fuel flow until you get a stable air-free supply to the container.
h. Pump 2 litres into a calibrated container and record the elapsed time.
i. Set the master switch to OFF.

Result.
j. The time to supply 2 litres of fuel must be approximately 1 minute.
k. If the time is much greater than 1 minute with a clean filter installed, find and correct the problem.
l. The test is complete if the result is in this range.

Page 501

MAINTENANCE MANUAL SUPPLEMENT 28-20-00- Fuel Flow Test
C550GT-AD016-FU24-0213
Fuel Flow Test Revision: Initial Issue DATE: 01/01/2020

Fuel Flow Test Maintenance Practices / Adjustment & Test
Adjustment & Test

1. Fuel Flow Test.

When you change a Fuel Distribution System component, always do a Fuel Flow Test.
Connect the aircraft electrical system to a Ground Power Unit (GPU) during the test.
Make sure you install a clean Airframe Fuel filter-element for the test. If the average period for the specified fuel
quantity is more than the maximum, change the filter and do the test again.

CAUTION: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS.

Pre-test Preparation.
(1) Level the aircraft laterally and longitudinally. Go to 08-00-00 Leveling and Weighing

CAUTION: CONNECT A GROUND CABLE TO THE AIRCRAFT TO ELIMINATE THE DANGER OF ELECTROSTATIC
DISCHARGE.

(2) Make sure the total fuel tank quantity is greater than 75 litres of fuel.

(3) Remove the engine cowl. See Chp. 71 Engine Cowling

(4) Disconnect the flexible hose from the inlet to the engine fuel/oil heater.

NOTE: Refer to the P&WC EMM, 73-10-01 - Oil-To-Fuel Heater, Section 5. Removal/Installation. Para. A.
Removal of Oil-To-Fuel Heater (ref. fig. 201)

Ref. Ext. Doc: P&WC Maintenance Manual, Turboprop Gas Turbine Engine, Model PT6A-15AG Manual Part No.
3030442 (latest revision).

NOTE: Put a protective cap on the inlet fitting of the fuel/oil heater unit.
(5) Connect an extension hose to the removed fuel supply hose.
(6) Put the free end of the hose in a container positioned at the same height as the engine fuel/oil heater.

WARNING: MAKE SURE PERSONNEL ARE AWARE OF THE DANGERS OF FUEL IN AN OPEN CONTAINER.

Test Procedure.
NOTE: Two persons are necessary to do this procedure. One person in the cockpit and one person outside at
the fuel container.

CAUTION: OBSERVE ALL FIRE AND SAFETY PRECAUTIONS.

(1) Connect the aircraft to a Ground Power Unit (GPU).
(2) Set the Master Switch to ON.
(3) Set the Fuel Shut-off Valve to the ON position.
(4) Let fuel flow until you get a stable air-free supply to the container.
(5) Pump 4.5 litres into a calibrated container and record the elapsed time.
(6) Set the Fuel Shut-off Valve to the OFF position.
(7) Set the master switch to OFF.
(8) Do steps 3 thru 6 more than five times, then calculate an average time.
(9) Set the Fuel Shut-off Valve to the OFF position.
(10) Set the master switch to OFF.

Result.
The average time to supply 4.5 litres of fuel must not exceed 52 seconds.
If the average time is greater than 52 seconds with a clean filter installed, find and correct the problem.
The test is complete if the result is less than 52 seconds.

Post test Procedure.
(11) Remove the extension hose used for the test.

(12) Remove the protective cap from the inlet fitting of the fuel/oil heater unit.

Page 502

MAINTENANCE MANUAL SUPPLEMENT 28-20-00-Fuel Flow Test
C550GT-AD016-FU24-0213
Fuel Flow Test Revision: Initial Issue DATE: 01/01/2020

Maintenance Practices / Adjustment & Test

(13) Install the flexible fuel supply hose onto the inlet to the engine fuel/oil heater.
NOTE: Refer to the P&WC EMM, 73-10-01 - Oil-To-Fuel Heater, Section 5. Removal/Installation. Para. A.
Removal of Oil-To-Fuel Heater (ref. fig. 201)

Ref. Ext. Doc: P&WC Maintenance Manual, Turboprop Gas Turbine Engine, Model PT6A-15AG Manual Part No.
3030442 (latest revision).

(14) Do a System Leak Check. See Chp. 28 Fuel Distribution Leak Test.
(15) Install the engine cowl. See Chp. 71 Engine Cowling

Page 503