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这是一个对CVFDR的一般介绍，包括：ＣＶＦＤＲ的历史，飞参的参数的一般介绍，以及参数的校验等等。
Flight Data Recorder Read-Out Technical and Regulatory Aspects
Table of Contents
GLOSSARY ..........................................................................................................4
SCOPE..................................................................................................................5
1 - TECHNICAL ASPECTS...................................................................................6
1.1 Technical Evolution of FDRs.......................................................................................6
1.1.1 Metal foil and photographic film recorders ................................................6
1.1.2 Magnetic Tape Recorders.........................................................................6
1.1.3 Acquisition unit..........................................................................................7
1.1.4 Solid state recorders.................................................................................7
1.1.5 Non-protected recorders ...........................................................................8
1.2 Data Acquisition System..............................................................................................9
1.2.1 Data acquisition computer operational concept ........................................9
1.2.2 Data Frame Layout ...................................................................................9
1.2.3 Parameter decoding..................................................................................9
1.3 Recording System Operational Check................................................................... 10
1.3.1 Verification of recorded parameters........................................................10
1.3.2 Calibration of measuring and processing channels.................................11
2 - OPERATIONAL AND REGULATORY ASPECTS.........................................14
2.1 Overview of Regulations........................................................................................... 14
2.1.1 Introduction .............................................................................................14
2.1.2 Annex 6, Part I ........................................................................................14
2.1.3 JAR OPS 1 and OPS 1...........................................................................17
2.1.4 French texts ............................................................................................18
2.1.5 Information on US regulations ................................................................19
2.2 Comparison of regulatory requirements ............................................................ 20
2.2.1 Programme for analysis of recorded parameters....................................20
2.2.2 Inspection of FDR systems.....................................................................20
2.2.3 Calibration of measuring and processing channels.................................. 21
2.2.4 Documentation within operators area of responsibility............................22
2.3 Problems encountered during FDR operations.................................................... 23
2.3.1 Missing or incomplete data .....................................................................23
2.3.2 Incomplete or unavailable data frame layout documents........................24
2.3.3 Calibration issues....................................................................................27
2.4 Survey of 20 French Airlines .................................................................................... 28
2.4.1 Airline participation..................................................................................28
2.4.2 FDR maintenance...................................................................................28
2.4.3 Lessons Learned programme and flight data analysis............................28
2.4.4 Data frame layout documents .................................................................29
2.4.5 Measuring and processing channel calibration .......................................30
2.4.6 Summary ................................................................................................30
3 - CONCLUSIONS.............................................................................................32
4 - SAFETY RECOMMENDATIONS...................................................................33
4.1 Installation of FDRs on Aircraft................................................................................ 33
4.2 Data Frame Layout Documents ............................................................................... 34
4.3 Recording Quality....................................................................................................... 34
4.4 Verification of Recorded Parameters...................................................................... 35
4.5 Calibration of measuring and processing channels............................................ 36
LIST OF APPENDICES ......................................................................................37
Glossary
AMC |
Acceptable Means of Conformity |
ARINC |
Aeronautical Radio Incorporated |
BCD |
Binary Coded Decimal |
CAA |
Civil Aviation Authority (United Kingdom) |
|
CASA |
|
|
Civil Aviation Safety Authority (Australia) |
|
CVR |
|
|
Cockpit Voice Recorder |
DAC |
Direction de l’Aviation Civile (France) |
DAR |
Direct Access Recorder |
DFL |
Data FrameLayout |
DGAC |
Direction Générale de l’AviationCivile (France) |
|
DMU |
|
|
Data Management Unit |
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EASA |
|
|
European Aviation Safety Agency |
ED |
EUROCAE Document |
EGT |
Exhaust Gas Temperature |
EUROCAE |
European Organization for Civil Aviation Equipment |
FAA |
Federal Aviation Administration (USA) |
FAR |
Federal Aviation Regulations |
FDAU |
Flight Data Acquisition Unit |
FDR |
Flight DataRecorder |
GPWS |
Ground Proximity Warning System |
IRS |
Inertial Reference System |
JAA |
Joint Aviation Authorities |
JAR |
Joint Airworthiness Requirements |
kt |
Knot |
QAR |
Quick AccessRecorder |
ICAO |
International Civil Aviation Organization |
MOPS |
MinimumOperational Performance Specifications |
NTSB |
National Transportation Safety Board(USA) |
SFACT |
Service de la Formation Aéronautiqueet du Contrôle Technique (France) |
SSCVR |
Solid State Cockpit Voice Recorder |
SSFDR |
Solid State Flight DataRecorder |
SCOPE
The readout of Flight Data Recorders (FDR), whether performed in France or
elsewhere, often brings to light a variety of problems such as aircraft operators
having incomplete, outdated or inappropriate documents or not having the relevant
documentation at all. Sometimes this significantly delays the validation of the
readout work.
However, rapidly obtaining complete and accurate data after an accident or an
incident is often critical for the technical investigation and, in a broader way, to air
transport safety. Data extracted from FDRs help to determine causes and to
develop appropriate preventive measures.
There are no single guideline document relating to FDR regulations. Several
international and French texts touch on these aspects, though not always in a
coherent fashion.
In order to get a complete picture of the problems encountered, the BEA has
produced this study, based on the analysis of known issues and on consultations
with French aircraft operators. Its objective is to increase awareness among the
various actors of the importance of FDRs for accident prevention and to
recommend improvements.
1 - TECHNICAL ASPECTS
Flight recorders, often called “black boxes” by the media are two devices designed
to record data about flights. Flight Data Recorders (FDR) record various flight
parameters, whereas Cockpit Voice Recorders (CVR) record the acoustic
environment of cockpits. This study will be limited to FDRs.
1.1 Technical Evolution of FDRs
The aeronautical industry’s efforts to design recording devices that could sustain
accidental damage, such as impact and fire, date to the beginning of commercial
aviation. It was only in 1958 that aviation authorities began imposing minimum
specifications for flight recorders to aid technical investigations.
1.1.1 Metal foil and photographic film recorders
Boeing 707’s, DC8’s and Caravelles were the first jet engine aircraft to be equipped
with FDRs in the early sixties. These recorders consisted of a mechanical stylus
engraving a metal foil. For metal foil FDRs, the parameters are processed internally
with data coming in directly from basic aircraft sensors, such as accelerometers and
pitot tubes. At about the same time, a similar technology consisted of replacing the
sheet of metal with a photographic film and the mechanical stylus with light beams.
That was the photographic film FDR. Both types of FDRs could only monitor a
limited number of important parameters, usually 5 or 6, such as magnetic heading
and airspeed.
1.1.2 Magnetic Tape Recorders
Metal foil and photographic film FDRs started to fall behind in relation to
investigation needs in 1965. With the introduction of magnetic tape-based
recorders, it became possible to not only record conversations but also to
progressively increase the number of parameters monitored by FDRs.
With the new magnetic FDRs, parameters were no longer recorded in a single
stream. Instead, they were first sampled, digitalized and multiplexed inside a 1-
second long frame. Then, this digital frame was recorded on a magnetic tape
using simple signals to code 0’s and 1’s. Hence the name Digital Flight Data
Recorder (DFDR).
Inside a magnetic tape recorder
1.1.3 Acquisition unit
As the need for more parameters grew and as new digital technology appeared, it
became inadequate to have FDRs compute parameters internally based on data
received from sensors.
Flight data acquisition devices began to be designed to collect all parameters
before being recorded. These devices include the Flight Data Acquisition Unit
(FDAU), Flight Data Interface Unit (FDIU) or Flight Data Acquisition Card (FDAC).
They order data and then send it to FDRs, whose function is then limited to data
recording.
Note: Aircraft operators can modify FDAU programming.
It is important to note that mainly large aircraft in the public transport category are
equipped with data acquisition units. For smaller aircraft, the data acquisition
function is still often performed by FDRs.
1.1.4 Solid state recorders
With the evolution of digital technologies, solid-state memory cards replaced
magnetic tapes in FDRs around 1985. Recordings on these new Solid State Flight
Data Recorders (SSFDR) have far better restitution reliability than on the magnetic
FDRs.
As memory cards got smaller, the number of recorded parameters went up to
several hundred, sampling frequencies increased and recording times of some
models rose to 50 hours or more.
Sound recorders also benefited from this technological evolution, with not only the
possibility of recording sound digitally, but also with a recording time that was
extended to 2 hours as opposed to half an hour for magnetic tape-based CVRs.
1.1.5 Non-protected recorders
The introduction of data acquisition units has also benefited what is commonly
called “flight data monitoring”. FDRs were the only devices recording data and that
data was only used after an accident. Now, with data acquisition units, data is also
directed to other types of recorders.
These recorders are not protected. The recording media can be a tape, an optical
magnetic disc or a PCMCIA card. The recording media is designed to be removed
and replaced quickly. The access to the recording media is located either in the
cockpit or in the electronics bay.
Quick Access Recorders (QAR’s) usually record exactly the same data as FDRs.
Onboard an aircraft, the data acquisition unit feeds both the FDR and the QAR.
The most recent QARs also have input ports compatible with the standard aircraft
buses (ARINC 429) and can therefore receive additional data.
Direct Access Recorders (DARs) receive data from Data Management Units
(DMUs) and can be programmed not only to select which parameters to record
and with which sampling frequency, but also to select the recording mode: periodic
recording or recording triggered by events such as a parameter passing over a
pre-determined threshold.
These recorders are used for maintenance, research or flight data monitoring
purposes.
1.2 Data Acquisition System
1.2.1 Data acquisition computer operational concept
Data acquisition computers centralize and format data coming from sensors,
onboard computers and other instruments and then transfer it to FDRs via a
dedicated digital link (serial link ARINC 573 or 717). There are four types of input
data:
• Discrete (logical status detection, indicators, switches, relays);
• Analog (potentiometer);
• Synchronization transmitters;
• Digital bus (ARINC 429).
Data acquisition units are programmed to produce a continual flow of data towards
FDRs. They deal with the time sampling of parameters and of their digital
encoding from the actual physical value to the recorded value.
1.2.2 Data Frame Layout
FDR Data Frame Layout (DFL) documents depend on the type of recording
systems. They describe:
• the programming method used by the data acquisition system (location of
parameters, number of bits used to encode parameters, type and method of
encoding);
• the functions used to convert the recorded value into the actual physical value.
For each parameter, the conversion function is checked with the calibration of
the measuring and processing channel, as mentioned later in this document.
These documents are completed by calibration control reports on the mandatory
parameters.
1.2.3 Parameter decoding
Data acquisition systems output a binary file sequenced in four-second frames.
Each frame is divided into four one-second-subframes.
Each subframe is divided into 64, 128, 256 or 512 “words” of 12 bits each,
depending on the FDR’s technology. The bit is the basic binary unit whose value is
either 0 or 1.
1.3 Recording System Operational Check
The check on recorded parameters and the calibration check on measuring and
processing channels are complementary maintenance tasks that improve the
quality of recordings.
1.3.1 Verification of recorded parameters
1.3.1.1 Objective
The evaluation of the recording system’s general operation and of the quality of
data frame layout documents is performed through the check on recorded
parameters in FDRs. |
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常用的民航飞机维修单词
每天五小时努力一月，4.23日终于4级了（想
污水箱水量指示系统简介
关于二号窗互换性的问题
发表于 2015-6-14 11:35:32
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