Night Flying

Question 1

Retina

Answer 1

Back portion of the eye, contains receptors which record an image and send to brain

Question 2

Cones (color)

Answer 2

• center of the fovea
• further away from the fovea, then cones diminish
• purpose is to direct color and detail
• primarily for central vision (10 degrees)
• focal point- sensitive to color but not light

Question 3

Rods (light)

Answer 3

1. Primarily responsible for dark adaption
   - rhodopsin (visual purple) is produced by rods to make them more sensitive to light (10000X’s)
   - can take up to 30 minutes to adapt
   - avoid bright light prior to flight
   - use red or low light in flight
2. Rods are peripheral, requiring offset scanning 5-10 degrees
   - light enters trough lens
   - peripheral transmitted to rods (sensitive to light but not color)

Question 4

Adaption to changing light

Answer 4

1. Rhodopsin (visual purple is what allows eyes to see in the dark
2. Can take rods 30 minutes to completely form
3. Preservation of night vision:
   - avoid bright lights
   - above 5000’ use supplemental O2 (rhodopsin uses O2
   - smoking will inhibit dark adaption. As altitude increases, O2 available for dark adaption decreases. Use recommended supplemental O2

Question 5

Correction of eye during adaption

Answer 5

1. Night scanning:
   - off center viewing to expose rods to image
   - focusing with peripherals
   - short eye movements 10 degree intervals
   - scan for movement and lights
   - avoid looking directly at an object or fixating. retina will adapt to image and fade
2. Allow 30 minutes prior to night flight for dark adaption to fully form
3. Avoid bright lights
4. Use flashlight for preflight inspection
5. Ensure windows are clean and streak free (dirt and streaks glare)

Question 6

Illusions (Autokinesis)

Answer 6

• focusing on a light for a long period of time will make that light appear to move
• unknowingly the pilot will align A/C with light
• avoidance it to continue scanning

Question 7

Illusions (false horizon)

Answer 7

1. Lighting on the ground or stars may cause illusion of false horizon
   - terrain, slopping clouds, ground lighting
2. Pilot orients aircraft to match false horizon
3. Trust instruments and maintain scan

Question 8

Illusions (flickering vertigo)

Answer 8

• light passing through or reflecting from MR blades
• creates flashing light that may cause dizziness, nausea, or convulsions
• anti-collision light may cause this, if necessary turn off temporary

Question 9

Illusions (Night myopia/empty field myopia)

Answer 9

• I’m dark featureless environment, eye relaxes and focuses 10 to 30 feet ahead
• maintain constant scan, focus of various distances

Question 10

Illusions (featureless terrain)

Answer 10

• snow, sand, or water

- unaware pilot thinks they are higher then they actually are

Question 11

Illusions (penetration of fog)

Answer 11

• illusion of pitching up

Question 12

Illusions (depth perception)

Answer 12

1. Is unreliable
2. It relies on rods at night:
   - rods to not detect distance or rate of closure as well as cones

Question 13

Illusions (approach to landing)

Answer 13

• bright airport lighting may lead to higher then normal approach
• absence of visual references may lead to lower then normal approach

Question 14

Illusions (landing illusions)

Answer 14

1. Slopping runways
   - down slopped runway: pilot ends up flying to steep of an approach
   - upslope runway: pilot flies to shallow of an approach
2. Runway width illusion
   - wider then normal: pilot ends up to steep
   - narrower then normal: pilot ends up to shallow

Question 15

Illusions 9 types

Answer 15

1. Autokinesis
2. False horizon
3. Flickering vertigo
4. Night myopia/empty field myopia
5. Featureless terrain
6. Penetration of fog
7. Depth perception
8. Approach to land
9. Landing illusions

Question 16

Personal lighting devices

Answer 16

1. Use flashlight for preflight inspection
   - use strong white light, headlamp recommend
2. Red light in cockpit may wash out charts
3. Use map light when available and necessary
4. Red light is the best light to use when flying at night

Question 17

Equipment requirements FAA (FLAPA) Robinson (NAIL)

Answer 17

FAA required
F- fuses (spare set, accessible in flight)
L- landing light (if operated for hire)
A- anti-collision light
P- position lights
A- adequate source of electrical energy to power systems
position lights required from sunset to sunrise
Robinson required
N- navigation lights
A- anti-collision strobe
I- instrument lights
L- landing light
Ability to maintain visual reference to ground objects illuminated solely by the ground or adequate celestial illumination

Question 18

Location of aircraft navigation lighting

Answer 18

1. Position lights
2. Required from sunset to sunrise
   - red light on left side
   - green light on right side
   - white light located on tail
3. If you see a green light and red light
   - aircraft is moving towards you
4. See only green light
   - other AC is moving left to right direction
5. See only red light
   - other AC is moving right to left
6. Night operations require aircraft to be:
   - clearly illuminated
   - have position lights
   - be in an area marked by obstruction lights

Question 19

Airport beacons

Answer 19

1. Civilian- green/white
2. Military- green/white/yellow
3. Heliport- green/yellow/white
4. Water- yellow/white

Question 20

Pilot controlled lighting

Answer 20

1. When equipped, may be activated by pilot on CTAF freq
2. Activating by clicking transmit switch
3. 3 levels of intensity:
   - low- 3 clicks
   - medium: 5 clicks
   - high: 7 clicks
4. For 15 minutes

Question 21

Taxiway lighting

Answer 21

1. Edge lights: blue
   - note NVG cannot see blue light
2. Centerline lights
   - steady burning green light

Question 22

Runway lighting

Answer 22

1. Runway centerline
   - white until last 3000’
   - white/red until last 1000’
   - red until runway end
2. Runway edge lights
   - white until last 2000’ (most airports)
   - yellow last 2000’ for instrument runways
3. 3 intensities:
   - low: LIRL
   - medium: MIRL
   - high: HIRL
4. End of runways indicated by red/green lights
   - red indicates departure end for departing AC
   - green indicates approach end for approaching AC

Question 23

REIL (runway end identifier lights)

Answer 23

• provides rapid and positive ID of the approach end of the runway
• consists of a pair of synchronized flashing lights located laterally on each side of the runway threshold

Question 24

ALS (approach light system)

Answer 24

• begin at threshold and extend towards approach area
• used to transition from IFR to VFR
• various configurations

Question 25

VASI (visual approach slop identifier)

Answer 25

1. Provide visual descent guidance during approach 2. Visible from 3-5 miles day, 20 Miles night 3. Provides obstruction clearance of 10 degrees from centerline out to 4 NM 4. Use red and white lights - all red (your dead) below the glide path - all white (out of site) above glide path - red on white (your all right) on glide path

Question 26

2 bar VASI

Answer 26

- provides 3 degree glide slope | - uses 2 rows of lights

Question 27

3 bar VASI

Answer 27

1. Provides 2 separate glide slopes 2. Near and middle indicate 3 degree 3. Middle and far indicate 3 1/4 degree - higher glide slope intended for high cockpit aircraft

Question 28

Tri color VASI

Answer 28

1. Uses a single light 2. Changes color depending on glide path: - Red = below glide path - Green = on glide path - Amber = above glide path 3. Visual from 1/2 mi day, 5 mile night

Question 29

Pulsating VASI

Answer 29

1. Uses a single light 2. Changes color and flashes depending on glide path: - Flashing red = below glide path - Solid red = slightly below glide path - Solid white= on glide path - Flashing white= above glide path 3. Visible from 4 mi day, 10 mi night

Question 30

PAPI (precision approach path indicator)

Answer 30

1. Uses single row of two or four light 2. Red/white Red on right, white on left: - All red = below glide path - 3 red, 1 white= slightly below - 2 red, 2 white= on glide path - 1 red, 3 white= slightly above - all white = above the glide path 3. Visible from 5 mi day, 20mi night

Question 31

Other lighting info Red obstruction lights High intensity white obstruction lights Dual lighting

Answer 31

1. Check A/FD or any NOTAMS to find out available lighting systems Aviation obstructions: 1. Red obstruction lights - flashing red beacons, and steady burning aviation red lights 2. High intensity white obstruction lights: - flashing high intensity for day time - reduced intensity for twilight and night time 3. Dual lighting: - combo of flashing red beacons and steady burning red lights for night time operations, and flashing high intensity white lights for daytime ops

Question 32

Switches, fuses, circuit breakers pertinent to night ops

Answer 32

Fuses: - a spare set of each kind used - must be accessible in flight

Question 33

High altitude performance considerations

Answer 33

1. OGE/IGE hover ceiling 2. Limited power/lift 3. Supplemental oxygen regs 4. Enroute high altitude charts above 18000' MSL 5. Advantages: - better visibility - less turbulence - above weather - reduced chance for icing - capability to see and avoid thunderstorms

Question 34

Components of the eye

Answer 34

1. Retina 2. Cones 3. Rods