FIELD OF THE INVENTION
This invention relates to Test Facility for Hardware Testing of Flight Data Recorder
(FDR) in integrated Phase and, more particularly, for testing of hardware modues of flight data
recorder and FDR system for serviceability of the FDR System.
BACKGROUND OF THE INVENTION
A Solid State Flight Data Recorder (SSFDR) records the aircraft flight information in
digital format using solid state semiconductor memory as a recording medium. With the
evolution of digital technologies, solid state memory replaced magnetic tapes in FDRs. It is a
kind of combi-recorder to record both specific aircraft performance parameters and audio data -
conversation in the cockpit, radio communications between the cockpit crew and air traffic
control personnel as well as ambient sounds. Here, both FDR and CVR functions have been
combined into a single LRU. The modular design allows simplifying the assembly process and
improving the serviceability of the unit.
SSFDR popularly referred to as a "Black Box". The data recorded by the SSFDR is
used for accident investigation, as well as for analysing air safety issues, material degradation
and engine performance. Data extracted from SSFDR helps to determine causes and to
develop preventive measures. Due to their importance in investigating accidents, SSFDR is
carefully engineered and stoutly constructed to withstand the force of a high speed impact and
the heat of an intense fire so that information recorded by it may be used to reconstruct the
circumstances leading up to the accident. Contrary to the "Black Box" reference, the exterior of
the FDR is coated with heat-resistant bright orange paint for high visibility in wreckage, and the
unit is usually mounted in the aircraft's empennage (tail section), where it is more likely to
survive a severe crash.
Separate Acceptance Test Procedures are devised for the standalone testing of the
individual modules before integration and performance of Hardware Functional Tests. These
test procedures may also be used to ascertain the health of the cards before, during or after
screening tests, if any, as applicable.
Of the above modules, CPU module and Audio module are tested by connecting the
same to a PC, with terminal emulation program. The on-board diagnostics program is used to
test these modules
The I/O modules, i.e. the Analog module, ‘Discrete’ module and ARINC / Frequency
module are tested with a Test Jig, which enables simulation of the I/O signals, as well as bus
interface signals. Using this jig, it is possible to perform read and write operations to any
identified address on the module, to enable functional testing of the modules.
Test Equipment for FDR in Integrated Phase has been made up with complete hardware
in a 19” rack mountable Enclosure having the facility to monitor all the parameters on front
panel. USB based Controller Chassis along with associated interface electronics are placed
inside the enclosure of the test equipment. It is used to generate various signals required to
carry out card level acceptance test, hardware functional test and system acceptance test of
FDR unit.
SUMMARY OF PRESENT INVENTION
The test equipment mainly consists of following parts:
• USB based Controller NI cDAQ Chassis & I/O Modules
• USB to RS-232/422/485 Converters (NUDAM 6530)
• PCMCIA based MIL-STD-1553B Card
• Interface Electronics (Signal Generation Board & Loop back Interface Board)
• Break-In-Break Out (BIBO) & Monitoring Panel
• CCC Power Supply Module
• SMPS (AC to +27V / 5.56A DC)
• USB Hub
• Rugged Laptop
The USB based controller chassis with Input/output modules and USB to RS-
232/422/485 converters are connected to USB bus of Laptop through USB hub. The controller
chassis with I/O modules provides analog, discrete and frequency input/outputs to FDR. Before
passing to FDR signals are conditioned by the signal conditioning board, if required, otherwise
directly.
USB to RS-232/422/485 module provide RS-422 interfaces for telemetry and Flight
Control System data. Generated signals are connected to FDR through BIBO and monitoring
panel.
The PCMCIA based MIL-STD-1553B Card is installed in Laptop’s PCMCIA type II slot to
get MIL-STD-1553B interface to simulate Bus- Controller (BC). MIL-STD-1553B bus is
connected to FDR through stub.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the present invention become more apparent and
descriptive in the description when considered together with figures/flow charts presented:
Figure 1: is a Block Diagram of Test Facility for Hardware Testing of FDR in Integrated
Phase
Figure 2: is a Block Diagram of cDAQ Controller of TE
Figure 3: is a Block Diagram of Front View Chassis of Test Equipment
Figure 4: is a Block Diagram of Connection Diagram of MIL-1553B Card with FDR
Figure 5: is a Block Diagram of Signal Generation Module of TE
DETAILED DESCRIPTION
The following hardware items are required to conduct the test:
USB BASED CONTROLLER cDAQ CHASSIS:
cDAQ Controller Chassis and IO module is USB based systems. The system
configuration as shown in Figure: 1 consists of the following modules:
• System Slot : cDAQ Controller Chassis
• Slot1 : Analog Output Module1
• Slot2 : Analog Output Module2
• Slot3 : Analog Output Module3
• Slot4 : Analog Input Module
• Slot5 : Digital Input /Output Module
• Slot6 : Digital Input /Output Module
• Slot7 : Digital Input /Output Module
• Slot8 : Digital Input /Output Module
CONTROLLER CHASSIS
The cDAQ chassis is an eight slot USB chassis designed to use different types of I/O
modules like analog I/O, digital I/O and Timer/Counter etc. This is provided with a High Speed
USB 2.0 interface to communicate and program download from host PC/Laptop. The cDAQ
system consists of three parts:
• I/O modules
• cDAQ modules interface
• USB-STC2
These components digitize signals, perform D/A conversions to generate analog output
signals, measure and control digital I/O signals, and provide signal conditioning.
I/O MODULES:
All these I/O modules are hot swappable and automatically detected by the cDAQ
chassis. I/O Channels are accessible using driver software. The modules contain built-in signal
conditioning for extended voltage ranges or industrial signal types.
CDAQ MODULES INTERFACE:
The cDAQ Modules interface manages data transfer between the USB- STC2 and the
I/O modules. This also handles auto detection, signal routing, and synchronization.
USB-STC2:
The USB-STC2 features independent high speed data streams; flexible AI and AO
sample timing, triggering, PFI signals for multi-device synchronization, flexible counter/timers
with hardware gating, digital waveform acquisition and generation, and static DIO.
The functions of each LED/Switch are as explained:
• ON/OFF switch - is to switch ON/OFF of DC supply
• USB Port – to connect the system to laptop through hub
• Jack pin port – to connect DC power supply of 11-30V
• Ready/Active LEDs – indicates status of controller
PCMCIA BASED MIL-STD-1553B CARD & ACCESSORIES:
This card is inserted in Laptop’s PCMCIA type II slot to get MIL-STD-1553B interface.
MIL-STD-1553B bus is connected to FDR through transformer-coupled stub. To provide MIL-
1553B interface as shown in the figure 5, the following accessories are used:
• PCMCIA MIL-STD-1553B Card - 1Qty
• Transformer coupled 4-port stub – 1 Qty
• Termination Resistance, 78ohms, 1W – 2 Qty
• MIL-1553B Cable, 78ohms, 1m length – 2 Qty
This card has the following features:
• Dual redundant MIL-STD-1553B bus
• Multi functions: Bus Controller, Monitor and Remote Terminal
• The transition cable supplied provides access to the MIL-1553B and I/O signals
When connected to the P2 connector of transition cable provides up to four twinax
connectors for connection to the transformer coupled "A" and "B" MIL-1553B busses of each
channel. These connectors are labeled according to the channel and bus that they connect to,
i.e. CH2-B. The cable also has a 9- pin female D subminiature type connector that provides the
signals described in the following pin assignments:
SIGNAL GENERATION BOARD:
Signal Generation board performs the following functions:
• Generation of discrete signals
• SSCDR functional mode generation
• RLT signal generation
• Audio signal amplifier & 2nd order filter
• Amplifier circuit for XNH frequency
• Generating ±12.5V for discrete signals

WE CLAIMS:-
Accordingly, the description of the present invention is to be considered as illustrative only and is for the purpose of teaching those skilled in the art of the best mode of carrying out the invention. The details may be varied substantially without departing from the spirit of the invention, and exclusive use of all modifications which are within the scope of the appended claims is reserved. The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Test Equipment is capable of simulating the various signals like analog, discrete, Synchro and video. Test facility for Testing of FDR in Integrated Phase comprising; FDR unit receive the electrical signals simulated by the test equipment and perform the signal conditioning with the help of processors reside in the FDR; said simulation means parameter of all signals are generated with the test equipment on the basis of past data available for comparing the real data to past data; said built in test for UUT means checking the health of the unit with communication interface.

2. Test facility for Testing of FDR in Integrated Phase of claim 1 wherein equipment is capable of simulating the various signals like analog, discrete, Synchro, MIL-1553B and RS422 (FCS Data) etc. The FDR Unit receive the electrical signals simulated by the test equipment and perform the signal conditioning with the help of processors reside in the FDR.

3. Test facility for Testing of FDR in Integrated Phase of claim 1 wherein FDR consist the RS 422 interface on which it transmit the sensors data in HEX format after processing on the request by SMDS or Test Equipment through RS 422.

4. Test facility for Testing of FDR in Integrated Phase of claim 3 wherein the processed data in HEX format received from the FDR through RS 422 is converted into engineering value by the Test Equipment with the help of applicable conversion formula and same is compared with simulated value and checked for tolerance.

5. Test facility for Testing of FDR in Integrated Phase as claimed in any of the preceding claims wherein the switching command consist the information regarding input and output various Channel. Operator/User has to visually verify the output of switched channels on the Signal Panel.

6. Test facility for Testing of FDR in Integrated Phase as claimed in any of the preceding claims wherein test Equipment is also having the test facility to perform the Built-in-test of the FDR.

7. Test facility for Testing of FDR in Integrated Phase of claim 6 wherein test Equipment sent the command to FDR to perform the built-in-test through RS 422 port. FDR perform its BIT test and send the test result in HEX format to the test equipment. Test Equipment decodes the HEX data and display the result of all major components.

8. Test facility for Testing of FDR in Integrated Phase of claim 7 wherein test equipment can also detect any of the faulty cards in the FDR. It can display the health of all the individual cards of FDR. Detail test report can be generated in PDF format with time stamping at the end of the testing.

9. Test facility for Testing of FDR in Integrated Phase of claim 2 wherein the PCMCIA based MIL-STD-1553B Card is installed in Laptop’s PCMCIA type II slot to get MIL-STD-1553B interface to simulate Bus- Controller (BC). MIL-STD-1553B bus is connected to FDR through stub.

10. Test facility for Testing of FDR in Integrated Phase of claim 2 wherein USB to RS-232/422/485 module provide RS-422 interfaces for telemetry and Flight Control System data. Generated signals are connected to FDR through BIBO and monitoring panel. ,TagSPECI:As per Annexure-II