UH-60A Blackhawk Study Sheet
05 September 2007
Eng RPM % RPM 1&2
Stater Hot Wx
Airspeed Limits
12 Second Trans
105-107%
Transient
101-105%
Continuous
95-101%
Transient
91-95%
Avoid
20-40% and 60-90%
Temp.
<15
>15-52
193
Vne
180
Max Landing Light Ext.
Max Search Light Ext.
170
1 Hyd Pump Inop
1 SAS Inop
Max Gunner Win. Open
150
Max Auto <16825 GW
2 Hyd Pump Inop
2 SAS Inop
145
Max Cabin Doors Open w/No
sound proof or secured proper
140
2 Hyd Pump Inop IMC
2 SAS Inop IMC
Sling Load Weight up to 8,000
130
Max One Engine Inop.
Max Auto >16825 GW
Main Rotor % RPM R
Power on:
Transient
Continuous
Transient
Power Off:
Maximum
Transient
Normal
101-107%
95-101%
91-95%
110%
105-110%
90-105%
Attempts
2 / 3 min cool / 2 / 30 min
2 / 30 min cool
Slope Landing
Nose Up/Right/Left 15 deg
Nose Down 6 deg 15k Max Tail Wind
Minus 2 deg for every 5 knots wind
Landing Gear (Abuse Limit)
GW
<16825
>16825
Level
540 fpm
300 fpm
Slope
360 fpm
180 fpm
Bank Angle
Primary Servo Illum
Eng Ng
12 Second Trans
30 Minute Limit
Continuous
102-105%
99-102%
0-99%
Eng TRQ
Continuous Dual Eng 0-100%
Continuous Single
0-110%
12 Second Trans.
Dual Eng.
100-125%
Single Eng.
110-135%
Eng Oil Pressure
Continuous
Above 90% Ng
20-100 psi
min 35 psi
Eng Oil Temp
30 Minute Limit
Continuous
135-150 deg
-50-135 deg
TGT
12 Second Tran.
Start Abort
30 Minute Limit
Normal
850-886 deg
850 deg
775-850 deg
0-775 deg
Transmission Oil Pressure
Precautionary
65-130 psi
Normal
30-65 psi
Idle
20-30 psi
Steady State
45-55 psi
>10 degree up
30-35 psi
>15 degree up
10-15 psi
May flux up to 30 min.
30 deg
Windshield Anti-Ice
Do not test if OAT
>27 deg
105-120 deg
-50-105 deg
Back-up Pump Hot Wx
With rotor system static
Temp.
Oper.
Cooldown
-54-32
Unlim.
Unlim.
33-38
24 min. 72 min.
39-52
16 min. 48 min.
Auto w/ Stab Failure
110
Max glide w/100% RPMR in
Clean Config.
100
Search Light Ext By
Max glide w/100% RPMR in
High Drag Con.
Max A/S Cabin Doors open
w/sound proofing not secured
80
Recommended Autorotation
60
Max G.S. for Roll-On landing
45
Max Hover Side/Rear
Max Wind Vel. Start/Stop
40
< Stab full down, manual
> Stab 0 deg, manual
35
Side/Rear ERFS/Sling
30-50
Stabilator starts program.
High Speed Yaw
Avoid full pedal inputs
>80 kts
APU Operating Hot Wx
Temp/Cond
>43 deg/Rotor Oper.
<51 deg/No Rotor
Time
30 min.
continuous
Prohibited Maneuvers
Hover turns
>30 deg / second
Pitch
> + 30 deg
Roll
> 60 deg
2 PCLs simul. Idle / Off in flight
Rearward ground taxi
Landing/Search Light Ext.
Light Extend By Don’t exceed
Landing 130 kts
180 kts
Search
100 kts
180 kts
Hyd/SAS Inop A/S Limits
1 Hyd/SAS inop
2 Hyd/SAS inop
2 Hyd/SAS IMC
170 kts
150 kts
140 kts
Vne
193 kts
Gunner’s Window 170 kts
A/S Eng Inop
130 kts
Transmission Oil Temp
Precautionary
Continuous
120
Autorotation Airspeed
Weight
<16825
>16825
Airspeed
150 kts
130 kts
Lights, and Switches
#1 and #2 Fuel Low
approx. 172 lbs
#1 and #2 Fuel Pres. drops
< 9 psi
Fuel filter bypass pop
8-10 psid
Fuel Boost pump
25-27 psi
#1 and #2 Eng. oil pres drops
< 20 psi
#1 and #2 Eng. oil temp above
150 deg
#1 and #2 PRI SVO pres
< 2000 psi
Boost SVO off
< 2000 psi
#1 and #2 Hyd Res. Low
< 60% cap
#1/ #2 Hyd Return bypass
100±10 psid
#1/ #2 Hyd Impd byp.
70+10 psid
Hyd. System pres.
3000 psi
Pilot Assist Pres Reducer btn pops > 1375 psi
Utility mod. velocity fuse closes ≥ 1.5 gpm
Xmsn oil temp
> 120 deg
Xmsn oil pres.
< 14 psi
Hyd pump temp labels
> 270°F
#1/ #2 Eng out light
< 55% Ng
Low Rotor
< 95% Nr
Np overspeed
106+1%
TGT limiting approx.
843 deg
Prepared for by CW4 RJ Smith
UH-60A Blackhawk Study Sheet
05 September 2007
Mechanical Mixing
Coll. to Pitch – Compensates for
rotor downwash on the stabilator.
Coll. to Roll – Translating Tendency.
Coll. to Yaw – Torque Effect.
Yaw to Pitch – Lift component of
Tail Rotor.
Electronic Coupling
Collective to Airspeed to Yaw –
Compensates for torque effect in
addition to Collective to Yaw mixing
based on collective position and
airspeed. Function of SAS 2/FPS
100% below 40 kts.>100kts.
AFCS
Enhances static stability and
handling qualities of the helicopter.
Four subsystems:
1. SAS
2. Trim
3. FPS
4. Stabilator
FPS
Basic autopilot – Enhances static
stability through long term rate
dampening in pitch, roll, and yaw. It
is the “Brain”. When coupled with
Trim FPS has 100% control author.
Above 60 Kts
Below 60 Kts
Att. Hold Pitch Att. Hold/ A/S hold
Att. Hold Roll Att. Hold
Hdg Hold Yaw Head Hold/Tn coor
These systems must be on and
operational for FPS to func. at 100%:
1. SAS 1 and/or SAS 2
2. Boost
3. Trim
4. Stabilator (NOT req., but helps)
Trim
Provides a gradient force, maintains
position of cyclic and tail rotor
controls, and provides muscle for
FPS. Consists of 2 electromechanical actuators (roll and yaw),
& 1 hydroelectromechanical
actuator. (pitch)
Boost required for operation.
Slip clutches req. 80 lbs max in yaw
and 13 lbs max in roll during
actuator jam. Hardover causes
caut/adv lights and could move
cyclic ½ inch or pedals ¼ inch.
SAS
Enhances dynamic stability through
short term rate dampening in pitch,
roll, and yaw. 5% control auth. each
SAS 1 (Analog)
Brain is SAS amp. in avionics
compartment. 5% cont. auth.
Input:
1. Pitch - #1 stabilator amp.
2. Roll – pilot’s vert.gyro
3. Yaw – in SAS 1 amp.
4. Airspeed – A/S transducer
Malfunction indicated by erratic
movement of helicopter (no lights).
SAS 2 (Digital)
Brain is SAS/FPS computer under
center console. 5% cont. auth.
Input:
1. Pitch - #2 stabilator amp.
2. Roll – roll rate gyro (Nose)
3. Yaw – yaw rate gyro (Nose)
4. Airspeed – Air Data transducer
Malfunction indic. by SAS 2 failure
advisory light on AFCS switch panel
5.
6.
7.
8.
Stabilator
Variable angle of incidence airfoil
that enhances the handling qualities
of the helicopter and improves static
and dynamic stability about the pitch
axis.
SCALP
Functions:
1. Streamlines w/ rotor downwash
at low speed (below 30 kts) to
min. nose up attitude from
downwash. (A/S & Air Data
Transducers)
2. Collective Coupling to min.
pitch attitude excursions due to
collective inputs. (Collective
Pos. Transducers)
3. Angle of Incidence decreases
above 30 kts. to improve static
stability. (A/S & Air Data
Transducers)
4. Lateral Sideslip to pitch
coupling to reduce
susceptibility to gusts. Stab up
for right pedal, stab down for
left pedal. (Lat. accelerometers)
5. Pitch Rate Feedback to
improve dynamic stability.
Dampen pitch excursions due
to turbulence or “G” forces.
(Pitch Rate Gyros)
POU
1.
2.
3.
4.
MOPS
Main fuel sequencing for eng.
starting and operation.
Over-speed protection (NP)
from ECU at 106+1%
Purges start fuel manifold and
nozzles during eng. start and
main fuel manifold and nozzles
on shutdown to prevent coking.
Start fuel sequencing for eng.
start.
HMU
Basic fuel control; incl. high pres.
fuel pump & variable geometry
servo-actuator.
PM CAN VETO
Functions:
1. Pumps fuel at high pressure
2. Meters fuel to POU in response
to PAS, LDS, trq. motor from
ECU, & eng. variables.
3. Collective Pitch Compensation
through the LDS. When the
collective is moved, Ng is reset
for immediate Np response.
4. Accel/Decel flow limiting
preventing comp. stalls, eng.
damage, or flame out.
9.
Ng limiting – Limits max torque
available under low temp conditions.
Variable Geometry Positioning of
the inlet guide vanes for optimum
performance.
(ECU lockout) PAS Override &
Control with ECU Inoperative.
Allows pilot to mechanically bypass
torque motor inputs.
Torque Motor to Trim Ng Output.
To fine tune engine output. Can be
overridden in ECU lockout.
Opens Vapor Vent for manual HMU
priming, to remove air from HMU.
ECU
Controls electrical functions of engines
and transmits operation info to cockpit.
Functions:
1. Trims the HMU output through the TQ
motor determined by:
a. Isochronous Np Governing-ECU
will maintain Np reference set
by the pilot (Primary Function)
b. TGT Limiting (834-852°C). Except
during start, comp. stalls, or during
ECU Lockout.
c. Np reference, set by pilot
(INCR/DECR from 96-100%)
d. TQ Match/Load sharing. Torque will
increase to share, but not decrease.
(3% above reference)
2. Over-speed Protection. Switches close
when Np reaches 106+1% and open when
Np is below 106+1%.
3. Signals to cockpit for Np, TGT, and
Torque.
4. Sends signals to the history recorder.
Engine Alternator
Three windings for three functions:
1. Ng signal to cockpit tachometer.
(green)
2. Ignition power to the exciters during
start. (yellow)
3. ECU power. (yellow)
Weight-On Wheels Switch
(WOW) ITABUSHEA³
1.
IFF Mode 4-Auto Zeroize enabled in
flight.
2. Thermal protection for B/U pump
enabled on the ground.
3. Audio for low RPMR disabled on the
ground.
4. B/U Pump Auto OPN regardless of
switch position enabled in flight.
5. Underfreq. protection disabled in flt.
6. SAS/FPS computer degraded on gnd.
7. Hydraulic leak test disabled in fight.
8. ESSS jettison disabled on ground.
9. AFMS 5 min. delay enabled on gnd
10. AFMS PBIT/IBIT enabled on gnd.
Fuel Flow in the Engine
1.
2.
3.
4.
Pump (engine driven)
Fuel filter
HMU
Liquid to liquid cooler
5.
POU
Prepared for by CW4 RJ Smith