wnloads/MilitarySystems.pdf. It's a snapshot of the page taken as our search engine crawled the Web.
The web site itself may have changed. You can check the current page or check for previous versions at the Internet Archive. Yahoo! is not affiliated with the authors of this page or responsible for its content.
CRANE CO. Hydro-Aire Inc. Antiskid System Solutions for Military and UAV Aircraft CRANE CO. Hydro-Aire Inc.
Antiskid System Solutions
for
Military and UAV Aircraft
August, 2000
Hydro-Aire Inc.,
3000 Winona Avenue
Burbank, CA 91504
(818) 526-2600
www.hydroaire.com Hydro-Aire, the brake control specialists. Premier supplier to Military, Commercial,
Regional, and Business Aircraft manufacturers and operators
Hydro-Aire Inc.,3000 Winona Avenue, Burbank, California USA 91504 (818) 526-2600 Page 1
Table of Contents
Hydro-Aire Military Aircraft Brake Control Systems ................................................................... 2
Hydro-Aires Current Military Systems ........................................................................................ 2
Unmanned Aerial Vehicle (UAV) Braking Solutions ................................................................... 2
A TYPICAL TWO WHEEL, MARK IV, CONVENTIONAL ANTISKID BRAKE CONTROL SYS-
TEM .................................................................................................................................................. 3
Mark IV Conventional Antiskid Brake Control ......................................................................... 3
C-17 Mark IV Antiskid Control Valves ..................................................................................... 4
C-17 Mark IV Antiskid Control Valves ..................................................................................... 4
Wheelspeed Transducer ........................................................................................................ 4
C-17 Mark IV Brake Control Unit ............................................................................................ 4
Mark IV Antiskid Control Valve Schematic .............................................................................. 4
A TYPICAL FOUR WHEEL, MARK IV, CONVENTIONAL ANTISKID BRAKE CONTROL SYS-
TEM .................................................................................................................................................. 5
Mark IV Conventional Antiskid Brake Control ......................................................................... 5
Brake Control Systems for Unmanned (Pilotless) Air Vehicles ................................................ 6
X-34 Hydro-Aire equipped Research UAV ............................................................................. 6
Hydro-Aire Typical UAV Brake Control System Schematic ................................................... 7 Hydro-Aire, the brake control specialists. Premier supplier to Military, Commercial,
Regional, and Business Aircraft manufacturers and operators
Hydro-Aire Inc.,3000 Winona Avenue, Burbank, California USA 91504 (818) 526-2600 Page 2
Hydro-Aire Military Aircraft Brake
Control Systems
Military Aircraft, with their unique environmen-
tal and operational requirements, have always
been a significant element of Hydro-Aires
antiskid business. The first Hydro-Aire Mark I
antiskid was developed for the military Boeing
B-47 bomber in 1947. Military aircraft received
the benefit of the significant performance im-
provement available from the Hydro-Aire Mark
III slip velocity control with systems installed
on the F-4, F-15, F/A-18, C-9B, C/KC-135, C-27J,
and the B-1A/B. The C-17 was the first Military
aircraft to use the Hydro-Aire digital Mark IV
antiskid technology with an integrated Brake
Temperature Monitoring System (BTMS) and a
Mark IV system is provided for the C-130J.
Hydro-Aires Current Military Systems
Hydro-Aire continues to make state of the art
solutions for existing and new Military Aircraft.
Very reliable, high MTBF wheel speed transduc-
ers, modern digital electronics, hydraulic brake
control valves optimized for the control of brak-
ing, and new technologies like electric brakes
are all part of the Hydro-Aire product range.
Hydro-Aire antiskid and brake control systems
have been developed for a number of different
categories of military aircraft, from fighters to
bombers, tankers and transport aircraft. Sys-
tems include Mark III (analog) systems for the F-
15 and F/A-18, Mark IV (digital) systems for the
C-130J, Mark III (analog) systems for the C/KC-
135, and Mark V (Brake-By-Wire) systems for
the X-35 Lockheed JSF demonstrator, and the X-
33, X-34, and Tier II unmanned vehicles.
Aircraft landing gear, including brakes and tires,
are the highest cost support item on an aircraft
after the engines and Hydro-Aire provides tech-
nologies to extend brake and tire life. These
antiskid and brake control systems can quickly
pay for themselves and unlike every other brake
control supplier, Hydro-Aire has no conflict of
i n t e r e s t i n e x t e n d i n g b r a k e l i f e .
Military planners developing training systems
will want to have antiskid installed so that pilots
will learn how to correctly use and understand
antiskid. Hydro-Aire is developing solutions to
make systems more affordable on light aircraft
to meet this critical need.
Unmanned Aerial Vehicle (UAV) Braking
Solutions
Hydro-Aire designed and built the system in use
on the pioneering Global Hawk aircraft, bring-
ing 53 years of experience to the development of
UAV braking systems. Similarly, Hydro-Aire
systems are provided for the unmanned X-33
and the X-34 Research Vehicles.
Unmanned aircraft have unique requirements;
there is no pilot to decide when to apply brake
pressure or react to the feel of the airplane, so
braking must be automatic and must not intro-
duce any directional control or stability prob-
lems. Hydro-Aire has unique qualifications to
provide this type of brake control solution for a
UAV. With more than 20 years experience in
providing automatic braking systems and an
industry leading brake control technology, Hy-
dro-Aire can provide a system to confidently
meet the unique needs of UAV vehicles. Hydro-Aire, the brake control specialists. Premier supplier to Military, Commercial,
Regional, and Business Aircraft manufacturers and operators
Hydro-Aire Inc.,3000 Winona Avenue, Burbank, California USA 91504 (818) 526-2600 Page 3
A TYPICAL TWO WHEEL, MARK IV, CONVENTIONAL ANTISKID BRAKE CONTROL SYSTEM
The figure illustrates a typical Hydro-Aire digital Mark IV two wheel conventional antiskid brake
control implementation. Commanded Brake Pedal input is a mechanicalcommand to the metering
valves. The antiskid control valves reduce the commanded brake pressure in response to
processed skid information. Some systems have a power brake valve driven by master cylinder
inputs, while others use direct mechanical inputs to power brake valves. Axle mounted wheel-
speed transducer signals are processed to provide an antiskid correction signal to the antiskid
valve, reducing commanded pressure to result in a brake pressure command that ensures maxi-
mum braking force and peak available wheel-
runway slip velocity. The digital Mark IV
control algorithms provide highly adaptive
control under the most demanding conditions
and consistently afford the highest available
braking efficiency under all runway conditions.
Mark IV Conventional Antiskid Brake Control
Wheelspeed
Transducer
Commanded
Pressure
valve current
V slip
Tire/Runway Interface
Brake pressure
Return
Valve
Driver
Velocity
Converter
mu
Pedal
Displacement
V
V
wheel
Velocity
Reference
Velocity
Comparator
Transient
Control
Compensation
Network
PBM
Integrator
Servovalve
Brake
WHEEL #1
LEFT MAIN WHEEL
WHEELSPEED
TRANSDUCER
& HUBCAP
BRAKE
BRAKE
BRAKE
CONTROL
UNIT
28 VDC POWER BUS
ANTISKID
CONTROL
VALVE
ANTISKID
CONTROL
VALVE
WHEEL #2
RIGHT MAIN WHEEL
PARK BRAKE
VALVE
ON
OFF
PARK/EMERGENCY
BRAKE
HYDRAULIC
SYSTEM
PRESSURE
RETURN
PILOT
LEFT PEDAL
CO-PILOT
LEFT PEDAL
PILOT
RIGHT PEDAL
CO-PILOT
RIGHT PEDAL
PRESSURE
SWITCH
TYPICAL TWO WHEEL
ANTISKID SYSTEM
IMPLEMENTATION
PILOT
METERING
VALVE
LOW PRESSURE
PUMP COMMAND
FAULT
ANNUNCIATOR
OUTPUT
WOW SWITCHES Hydro-Aire, the brake control specialists. Premier supplier to Military, Commercial,
Regional, and Business Aircraft manufacturers and operators
Hydro-Aire Inc.,3000 Winona Avenue, Burbank, California USA 91504 (818) 526-2600 Page 4
Mark IV Antiskid Control Valve Schematic
Wheelspeed Transducer
C-17 Mark IV Antiskid Control Valves
RETURN
RIGHT
METERED
PRESSURE
RIGHT
BRAKE
PRESSURE
LEFT
METERED
PRESSURE
LEFT
BRAKE
PRESSURE
6
1
2
3
4
5
es
C-17 Mark IV Brake
Control Unit Hydro-Aire, the brake control specialists. Premier supplier to Military, Commercial,
Regional, and Business Aircraft manufacturers and operators
Hydro-Aire Inc.,3000 Winona Avenue, Burbank, California USA 91504 (818) 526-2600 Page 5
A TYPICAL FOUR WHEEL, MARK IV, CONVENTIONAL ANTISKID BRAKE CONTROL SYSTEM
The figure illustrates a typical Hydro-Aire