UH-60A System Acronyms
Mechanical Mixing
Collective to Pitch -
Collective to Roll Collective to YawYaw to Pitch -
Compensates for rotor downwash on
stabilator. Increase collective – disk
tilts forward.
Compensates for translating tendency.
Increase collective – disk tilts left.
Compensates for torque. Increased
collective – T/R thrust increased.
Compensates for 2.5% lift of T/R.
Increase left pedal – disk tilts aft.
Functions of the Stabilator (SCALP)
S - Streamlines with rotor downwash @ A/S < 30 Knots
C – Collective Coupling; Increased collective stabilator
programs down.
A - Angle of incidence decrease as airspeed increases.
L - Lateral excursions (side-slip to pitch coupling); in
slip/skid rotor downwash differs with nose right/left.
P - Pitch rate feedback: Turbulance or wind gust – nose up –
stabilator down, nose down – stabilator up.
Weight on Wheel (WOW) Switch (ITABUSCHE)
I - IFF mode 4 – zeroize disabled in flight, auto code hold
before 1st takeoff.
T - Thermal protection for BACKUP PUMP on the ground.
A - Audio for low RPM R disabled on the ground
B - BACKUP PUMP in auto regardless of switch position in
flight.
U - Underfrequency protection disabled in flight.
S - SAS/FPS computer degraded on the ground.
C - Chaff dispense disabled on the ground.
H - Hydraulic leak test disabled in flight.
E - ESSS jettison disabled on the ground.
UH-60A System Acronyms
Engine Alternator (INE)
I - Igniter Power
N - Ng signal to cockpit
E - ECU Power
ECU Functions (NOT THIS)
N - Np reference from cockpit (96-100%)
O - Overspeed (Np) protection (1061%) redundant from
AC primary buses.
T - Torque matching/load sharing within 5%.
T - TGT limiting @ 837-849ºC
H - History recorder signals.
I - Isochronous Np governing.
S - Signals to cockpit for Np and Torque.
HMU Functions (PM CAN VETO)
P - Pumps fuel
M - Meters fuel.
C - Collective coupling through LDS.
A - Accel./decel. Fuel flow limiting.
N - Ng limiting
V - Variable Geometry positioning.
E - Engine power control through PAS (lockout)
T - Torque motor interface with ECU (trims Ng).
O - Opens vapor vents for bleed air and fuel prime.
POU Functions (MOPS)
M - Main fuel sequencing
O - Overspeed protection (Np) with signal from ECU
P - Purges start & main fuel manifolds.
S - Start fuel sequencing
UH-60A System Acronyms
Fuel Flow in the Engine (Path Finders Have Little
Potential)
P - Pump (Engine drive fuel pump)
F - Fuel Filter
H - HMU
L - Liquid to Liquid cooler
P - POU
GCU Functions (UFOVU)
U - Underfrequency protection (95% Nr on the ground 8589% Nr in flight).
F - Feeder Fault Protection (Short Isolation/Circuit
Protection)
O - Overvoltage Protection.
V - Voltage Regulation.
U - Undervoltage Protection
Less than 60 AXIS More than 60
Attitude Hold
P
Attitude Hold – A/S Hold
Attitude hold
R
Attitude Hold
Heading Hold
Y
Heading Hold or Turn Coordination
5 Lights which should be accompanied by the Backup
Pump Advisory Light
R - #1 RES LOW
H - #1 HYD PUMP
(Roy Has To Hurry Away)
T - #1 T/R SERVO
H - #2 HYD PUMP
A - APU ACCUM LOW
3 30 Minute Limits
TGT
NG
Temp - Oil