T-45A UJPT, E2-C2, ADV, & IUT Eng-09
Hydraulic System
(3) Hydraulic pressure is provided to
flight control services as long as
HYD 1 or RAT system remains
operational
b.
If HYD 2 EDP output pressure rises
above 2,000 psi, HYD 2 PRESS
caution light will go out
LECTURE NOTES
Explain that although the HYD 2 PRESS caution light
extinguishes at 2,000 psi, it may be illuminated with
over 2,000 psi showing on the HYD 2 pressure gauge.
This is because the gauge is indicating HYD 2 system
pressure; however, the HYD 2 caution light indicates
HYD 2 EDP output only. The HYD FAIL warning light,
unlike the caution lights, indicates low EDP pressure in
both systems as well as low emergency hydraulic
system pressure from the RAT.
2.
HYD 2 pressure falls below 1,500 psi
Overlay 1
a.
If HYD 2 pressure drops below 1,500
psi, emergency package assembly in
conjunction with the RAT accumulator
deploys the RAT
NOTE: Should the HYD 2 light not be
illuminated with the RAT EXTEND light
on, the HYD 2 lamp may be burned
out. This failure can be confirmed by
placing the MASTER TEST switch to
LAMP.
b.
If no leak in HYD 2, RAT will supply
hydraulic backup pressure for HYD 2
services (ailerons and stabilator)
(8-03) Original
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