lec 4: Data Collection - wreckage and site

Question 1

preliminary site survey

Answer 1

four corners etc
-geographical scope of the wreckage
- if not accounted for: expand scope of site
-reassess site for unforeseen hazards
-perishable data
- environmental damage/ damage to infrastructure (powerlines/ navigational aids)

Question 2

photography

Answer 2

camera basics
exposure triangle
camera/lens choice
techniques

Question 3

exposure triangle

Answer 3

aperture
shutter speed
iso

Question 4

aperture

Answer 4

iris
minimizes human eye
dilates/grows depending on how much light wanted
widening - shortens depth of field
narrowing - less light- deep depth of field

Question 5

shutter speed

Answer 5

how long (time seconds) sensor/film is exposed to light
wind/vibration = motion blur
- results of long shutter speed

Question 6

iso

Answer 6

sensitivity
turns gain up/down on sensor
iso comes from film
silver halide crystal on film
increase gain = grainey images - oversaturate bit depth
artifacts in image - pattern of pixels that appear as object

Question 7

metering

Answer 7

sets variables -2 fixed -1 not

Question 8

fix ISO, Aperture
modify shutter

Answer 8

controls
depth of field and graininess

Question 9

fix shutter and ISO
modify aperture

Answer 9

controls
depth of field and any blur

Question 10

fix shutter and iso
modify aperture

Answer 10

controls blur and graininess

Question 11

HDR

Answer 11

hydrodynamic range
using in challenging lighting situations
for challenging lighting conditions
reduces shadows

Question 12

focus stacking

Answer 12

multiple focus planes
each with narrow depth of feild

Question 13

3 axis

Answer 13

roll- adlerons
pitch - elevator
yaw - rudder

Question 14

continuity of control

Answer 14

levers, cables,pushrods, ball screws
all 3 axis (witness marks indicating position @ time of impact)
engine controls
prop controls
gear controls
identifying major components and controls
presence of all mechanism/ component per control system
push rods for cyclic collective
flaps/slats - jack screws

Question 15

major components
Check for the presence, and
document the state, of:

Answer 15

consult AMM,FCOM
Check for the presence, and
document the state, of:
* Engines
* Propellers
* Control surfaces
* Trim surfaces
* Gear/wheels/tires
* Flight recorders
* Etc

Question 16

useful manuals

Answer 16

aircraft flight manual (AFM)
aircraft maintenance manual (AMM)
component maintenance manual (CMM)
systems description manual (SDS)

Question 17

wreckage distribution
high speed + shallow angle (>10 deg)

Answer 17

angle = angle of incident
CFIT, Take off performance in climb

Question 18

wreckage distribution
high speed + steep angle (<10 deg)

Answer 18

spiral dive, control malfunction

Question 19

wreckage distribution
low speed + steep angle (<10 deg)

Answer 19

spin, deep stall

Question 20

spiral

Answer 20

aircraft not stalled
controllable
in VN envelope
no visual references outside (clouds/ nighttime)

Question 21

spin

Answer 21

aircraft not in control
angle on 1 wing (@ least) exceed
aircraft stalled
wing overs (departs)

Question 22

witness marks: material composite

Answer 22

tire
propeller

Question 23

See notes for formulas for calculations

Question 24

detailed site survey

Answer 24

• Gridding
• GNSS
• Transit
• 3D Laser scanning
• RPAS imaging
  /photogrammetry
• Photography/component
  catalogue
  wreckage distribution
  high resolution terrain topography (elevation)

Question 25

techniques least to most accurate

Answer 25

gridding technique ____increase fidelity/ precision GNSS +/- 10 ft DGPS Survey +/- 1 ft Surveyors Transit +/- 1 mm 3D Laser scanning +/- 1mm RPAS imaging with photo geometry (+/-1mm-1m)

Question 26

default position

Answer 26

keep/ sieze all of it