Unit Four: Hydraulic Systems

STUDENT GUIDE T-39N/G NATOPS

UNIT FOUR: HYDRAULIC SYSTEMS

REFERENCE: T-39 NATOPS MANUAL

ENABLING OBJECTIVE:

A-1. Locate and operate T-39N/G aircraft systems, given a mission in a T-39 in accordance with

NATOPS.

ENABLING STEP:

A.1.5. Recall the basic descriptions, related and operating limitations of the T-39N/G hydraulic

systems.

NATOPS FOUR: HYDRAULIC SYSTEMS

A. Main hydraulic system (3,000 psi system)

1. Components:

a. Electric motor driven pump (paralleling bus)

b. Hydraulic reservoir (2 gal.)

c. Accumulator (1500 + 50 psi nitrogen pre-charge)

d. Hydraulic pump switch

e. Cockpit-pressure gauge (2650-3200 psi)

2. Operates landing gear, main gear doors, speedbrake, wheelbrakes/anti-skid, thrust

reversers and NWS.

B. Controls and indicators

1. Switch positions

a. MANUAL - pump runs continuously; 1 minute time limit. Spring-loaded to AUTO.

b. AUTO - pump ON when pressure < 2700 psi until pressure returns to 3000 psi.

c. OFF&RESET - OFF position/resets power if tripped by overtime or overcurrent.

2. HYD PRESS PWR OFF LIGHT

a. Pressure < 2700 for more than 1 minute.

b. Switch is in OFF&RESET position.

c. Pump CB out (2A3 & 2A4).

HYDRAULIC SYSTEMS

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