70% N1 Leak Check [CFML]

TASK 71-00-00-790-809-A
70% N1 Leak Check

WARNING: MAKE SURE THAT THE LANDING GEAR GROUND SAFETIES AND THE WHEEL CHOCKS ARE IN POSITION. MOVEMENT OF THE AIRCRAFT CAN BE DANGEROUS.

WARNING: DO NOT DO AN ENGINE RUN-UP AT A POWER ABOVE IDLE WITH THE THRUST REVERSER COWLS AND THE FAN COWL DOORS OPEN. BEFORE YOU DO AN ENGINE RUN-UP AT IDLE WITH THE FAN COWL DOORS OPEN, MAKE SURE THAT THE COWL DOORS ARE SAFETIED BY ALL HOLD-OPEN RODS. IF YOU DO NOT OBEY THESE INSTRUCTIONS, INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT CAN OCCUR.

WARNING: - ENGINE OPERATION MUST NOT EXCEED MINIMUM IDLE WHEN PERSONNEL ARE IN ENTRY/EXIT CORRIDOR.

POSITIVE COMMUNICATION BETWEEN THE FLIGHT COMPARTMENT AND PERSONNEL IN ENTRY EXIT CORRIDOR IS NECESSARY.
INLET AND EXHAUST HAZARD AREAS MUST BE STRICTLY OBSERVED BY PERSONNEL IN ENTRY/EXIT CORRIDOR.

WARNING: MAKE SURE THAT:

THE PASSENGER DOORS ARE CLOSED AND THE PASSENGER LOADING STAIRS ARE REMOVED WHEN AT LEAST ONE ENGINE IS OPERATED ABOVE IDLE POWER.
THE CARGO DOORS ARE CLOSED AND CARGO LOADING EQUIPMENT IS REMOVED WHEN:

. ENGINE 2 IS OPERATED AT IDLE OR ABOVE . AT LEAST ONE ENGINE IS OPERATED ABOVE IDLE POWER IF YOU DO NOT OBEY THESE PRECAUTIONS INJURY TO THE PERSONNEL AND DAMAGE TO THE AIRCRAFT AND/OR EQUIPMENT CAN OCCUR.

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE PARTS AFTER THE ENGINE SHUTDOWN. USE APPLICABLE THERMAL GLOVES. THE ENGINE PARTS CAN STAY HOT FOR ONE HOUR AFTER SHUTDOWN AND CAN BURN YOU.

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	4	BOTTLE - PLASTIC
98F10103500000	2	CHOCK-MLG,ENGINE RUN-UP

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL, 438AR
FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL, 448AR

C. Referenced Information

REFERENCE	DESIGNATION
TASK 71-00-00-790-805-A	Fuel or Hydraulic or Oil Leakage Limits
TASK 71-00-00-790-806-A	Drain Mast Leakage Identification Procedure
TASK 71-00-00-860-827-A	Start the Engine (Normal Automatic Start)
TASK 71-00-00-860-829-A	Engine Shutdown
TASK 71-00-00-869-802-A	Wind Limitations During Engine Ground Operations
TASK 71-00-00-869-803-A	Safety Precautions During Engine Ground Operations
TASK 71-13-00-010-803-A	Opening of the Fan Cowl Doors
TASK 71-13-00-410-803-A	Closing of the Fan Cowl Doors
Tool Installation

3. Job Set-up
Subtask 71-00-00-941-150-A

A. Safety Precautions
(1) Obey the wind limitations and safety precautions during engine ground operation (Ref. AMM TASK 71-00-00-869-802) and (Ref. AMM TASK 71-00-00-869-803).

CAUTION: MAKE SURE THAT THE AIRCRAFT IS PARKED ON A CLEAN, DRY AND FLAT SURFACE. THERE MUST BE NO OIL, GREASE OR SIMILAR MATERIALS ON THE SURFACE. THE PAVEMENT MUST NOT BE BROKEN OR LOOSE, AND WE RECOMMEND CONCRETE MATERIAL BECAUSE ASPHALT CAN MELT AND CAUSE DAMAGE TO THE AIRCRAFT.

(2)

Tool Installation

(3) Make sure that a total of 3000 kg (6614 lb) (minimum) of fuel are in the inner tanks to make sure that the aircraft is stable during the test.

NOTE: This minimum fuel quantity does not include the fuel consumption of the engines necessary to do the test. This minimum quantity must stay in the inner tank at the end of the test.

(4) There must be two qualified persons in the cockpit when performing an engine run. One must monitor the outside and the aircraft behavior while the other performs the engine test.
(5) If the aircraft begins to move while performing an engine run, immediately set all the thrust levers to idle position.

4. Procedure
Subtask 71-00-00-790-067-A

A. 70% N1 Leak Check

WARNING: USE PERSONAL PROTECTION EQUIPMENT. USE THE ENGINE OIL IN A WELL-VENTILATED AREA. ENGINE OIL IS TOXIC.

(1) Prepare to collect the leakage during the engine run. Refer to (Ref. AMM TASK 71-00-00-790-806) to identify the drain(s) that will be collected.

NOTE: Use BOTTLE - PLASTIC to collect leakage.

(2) Make sure that the fan cowl doors are closed (Ref. AMM TASK 71-13-00-410-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR.
(3) Start the two engines (Ref. AMM TASK 71-00-00-860-827) and let them become stable at minimum idle for five minutes.
(4) Slowly accelerate both engines to 50 percent N1.
(5) On the landing gear control and indicating panel 402VU:

CAUTION: DO NOT OPEN LGCIU CIRCUIT BREAKERS 1GA, 2GA AND 52GA. IF YOU DO THIS, AIRCRAFT BRAKING THROUGH BRAKE PEDALS DOES NOT OPERATE.

(a) Make sure that the A/SKID & N/W STRG selector switch 5GG is set to ON.
(b) Make sure that the PARKING BRAKE control switch is in ON position.
(6) Push and hold the brake pedals at the full limit position.
(7) Operate the tested engine at 70 percent N1 or above it necessary to pressure the oil system and to get accurate results during the leak check.
(8) Operate the two engines at minimum idle and let them become stable for five minutes.
(9) After test completion, release the brake pedals to put the aircraft in the "parking-brake applied" configuration.
(10) Stop the Engine (Usual Engine Shutdown) (Ref. AMM TASK 71-00-00-860-829).
(11) Open the fan cowl doors (Ref. AMM TASK 71-13-00-010-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR.
(12) Measure the individual leakage quantity rate collected from each BOTTLE - PLASTIC (Ref. AMM TASK 71-00-00-790-805).

5. Close-up
Subtask 71-00-00-410-189-A

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Close the fan cowl doors (Ref. AMM TASK 71-13-00-410-803):
(a) FOR [4020KM1] (POWER PLANT-DEMOUNTABLE, ENGINE 1)
437AL 438AR
(b) FOR [4020KM2] (POWER PLANT-DEMOUNTABLE, ENGINE 2)
447AL 448AR
(3) Remove the WARNING NOTICE(S).

[Rev.10 from 2021] 2026.04.01 02:34:15 UTC