Electronic Standby Instruments System
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OASIS: Introduction
The OASIS is designed to serve as the secondary
source of cockpit instrumentation and provides
the following functions:
• Attitude
• Indicated Airspeed
• Barometric Corrected Altitude
• Slip/Skid
• Heading (Optional, requires a magnetometer)
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OASIS: LRU’s/Modular Design
The OASIS modular designed allows installation
flexibility by separating the display from the ASU
enhancing installation flexibility in congested cockpits
DU-1
(Display Unit)
ASU
MSU
(Aerosonic
Sensor Unit)
(Magnetic Sensing
Unit) Optional
DU-2
(Display Unit)
Optional
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OASIS: Standard System and Options
Standard system includes:
• ASU, 1ea.
• DU, 1ea.
Enhanced system options:
• Second DU
• DU with NVS
• ASU with internal standby battery
• MSU for heading reference
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OASIS: System Block Diagram
GROUND
POWER
Aerosonic
Sensor Unit
ASU
Power
Magnetic
Sensing Unit
(Optional)
Heading
Data
Attitude, Heading,
Airspeed, Altitude Data
Air Data
AHRS
Power
Air Data
AHRS Data
Power
AHRS
PILOT
CO-PILOT
Display Unit
DU-1
Display Unit
DU-2
(Optional)
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OASIS: Display Features
Battery
Status
Slip-Turn
Indicator
Airspeed
Tape
Altimeter
Tape
Magnified
Altitude
Window
Magnified
Airspeed
Window
Heading
Window
(optional)
Menu Select
Keys
Barometric
Setting
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OASIS: Part 27/29 Airspeed Window
Red
Min Airspeed
Max Airspeed
Color
0
VCAUTION
Green
VCAUTION
VNE Power ON
Yellow
VNE Power ON
Max Airspeed
Value
Red
VNE Power OFF
Red Cross-Hatched
Line
VNE power ON
Yellow
VCAUTION
Green
VNE Power OFF
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OASIS: Display Unit
The DU is installed on the instrument panel adjacent to
the primary display or instruments and provides a
secondary graphical display of all of critical, primary
functions necessary for the continued safe flight and
landing of an aircraft during a loss of primary
instruments. The DU provides user interface for data
entry and settings through a bezel keypad. The DU is
directly connected to, and obtains power and sensor
data from the remote mounted ASU.
Features:
• 4 inch diagonal screen
• 3 inch ATI opening
• Chassis depth: 1.35 inches
• Bezel: 4 inches x 3 inches
• Weight: .75 lbs
• NVS compatible (Option)
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OASIS: Display Unit
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OASIS: Aerosonic Sensor Unit
The ASU is a separate remote mounted LRU that
provides power and sensor data to the DU. It’s
connected to aircraft power and the pitot/static
pneumatic lines. The ASU contains sensors required
for the computation of Indicated Airspeed,
Barometric Corrected Altitude, Attitude, Slip/Skid.
Heading is available with the installation of an
Aerosonic Remote Magnetometer. Power to the
remote magnetometer is provided by the ASU. In
addition the ASU has an optional internal battery that
allows the OASIS to operate for a minimum of 1 hour
without aircraft power.
Features:
• Dimensions: 3 x 3 x 6.25 inches
• Weight: 2 lbs
• Power: 28 Vdc nominal, 14 watts max (2 displays, 1 ASU)
• Internal standby battery (Option)
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OASIS: Aerosonic Sensor Unit
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OASIS: Specification/Certification
Operating Specification
• Altitude: -1,500 to +55,000 ft.
• Airspeed: 20 to 450 kts
• Max roll/pitch rate: 200 deg/sec
• Operating temperature
• DU: -20º to +55º C
• ASU: -40º to +70º C
• Baro setting: 28.00 to 30.99 mb
• Reliability: 10,000 hrs MTBF
Certification
• Software: DO178B level B
• Environmental: DO 160F (Helicopter and Fixed Wing)
• FAA /EASA TSO
• TSO-C2d:
• TSO-C4c:
• TSO-C6e:
• TSO-C10b:
• TSO-C113:
• TSO-C3e:
• TSO-C46a
• TSO-C179
Airspeed Instruments
Bank and Pitch Instruments
Direction Instrument, Magnetic
Altimeter, Pressure Actuated, Sensitive Type
Airborne Multipurpose Electronic Displays
Turn and Slip Instruments
Maximum Allowable Airspeed Indicators
Rechargeable Lithium Cells and Lithium Batteries
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