Blackbox air craft investigation1234.ppt

air crash investigation

1. Aircraft Accident
Investigation
By:
Chinmay Patel
Roll No: 98001019

2. Outline
History of Flight Data Recording
Recording and Storage of Data
Flight Data Recorder (FDR)
Cockpit Voice Recorder (CVR)
Crash Survivability Features
Post Crash Procedures
Information Retrieval
Aircraft Reconstruction as a Technique

3. History
Wright Brother’s
recording of propeller
rotations
First Generation FDRs
Stainless Steel Tape
200 to 400 hrs of
information
1958: 1
st
mandate in
USA
1960: 1
ST
mandate in
UK
First Generation FDR

4. History
1970s: Second
Generation FDRs
FDAUs introduced
Magnetic Tapes used
1991: Solid State
Memory FDRs
34 Parameters for 25
hrs
Second Generation FDR

5. Recording and Storage
Magnetic Tapes
Track about 100 Parameters
30 minutes of CVR audio
Solid State Memory Boards: Stacked array of
memory chips
No moving parts
More reliable
More Parameters (~ 700)
25 hrs of FDR data + 2 hrs of CVR audio

6. Data Acquisition
Location on the Aircraft

7. FDR
Sensors FDAU


FDR
Minimum of 11 to 29
Parameters to be
Recorded
Eg: Time, Pressure
Altitude, Airspeed,
Heading, Accelerations,
Control Surface Settings,
Fuel Flow, Engine RPM
& Temperature… etc
Solid State FDR

8. CVR
Records all kinds of Cockpit Conversation,
Warning alerts & Noises
Various Microphones in the Cockpit record
sounds Pre-amplified Digitized
Stored
Re-write older material
Provide an idea of the Crew’s Situation &
Decisions taken

9. Crash Survivability
Crash Survivable
Memory Unit (CSMU)
Damage resistant
features
Aluminum housing
Dry Silica Layer for
insulation
Steel/Titanium shell
Thoroughly tested
against impact, fire and
environmental damage

10. Post Crash Procedures
Locating the Black Box
Orange in color
Underwater Locator
Beacon

Pulses of 37.5 kHz
every second for 30
days

Can transmit sound
from 14000 ft under
water

Can be tracked by
Ultrasound Sensors
 Black Boxes are transported
with utmost care
Kept in environment identical
to that in which it was found
ULB

11. Information Retrieval
Manufacturers supply NTSB with H/W & S/W
for Data Retrieval
Team of experts interprets the data from FDR
and the CDR audio
A typical team includes:
Airline representative
Airplane Manufacturer representative
NTSB Transportation-Safety Specialist
NTSB Air-Safety Investigator

12. Aircraft Reconstruction
2D as well as 3D reconstruction
Decide
Origin & Cause of Failure
Chain of Events
Important investigation technique
Better understanding of Failure Modes
Helps in ruling out false theories
Assurance that no possibility is left out

13. Comet G-ALYP Reconstruction
De Havilland Comet (1954)
Mid-air Explosion: 35 lives lost
Reconstruction provided clue to failure modes
Culprit: Fatigue failure of the stressed skin

14. TWA 800 Reconstruction
Boeing 747-131 (1996)
Mid-air Explosion
230 lives lost
Several Controversies
Reconstruction helped
to rule out false theories
Total of 876 pieces
arranged
Culprit: Explosion in
central fuel tank