Eric's garage full of shit for the final Flashcards
(111 cards)
1
Q
What effect will pressurisation have on the fuselage and its structural components?
A
Skin: puts skin under and tension in cycles, causing fatigue and reducing the life
Fasteners: Shear stress
2
Q
As an aircraft starts to near the end of its useful safe life due to pressurisation, what will likely be done? Why?
A
- Limit the aircraft operating altitude
- Will reduce the exposure to larger pressure differences, slightly prolonging the life of the aircraft
3
Q
What are the structural members of the semi-monocoque fuselage? Briefly describe each?
A
- Longeron: longitudinal structural members
- Bulkheads: Solid structures lying 90˚ to longerons
- Skin: Takes some of the load, the rest is transferred to the longhorns, stringers, formers and bulkheads beneath
- Formers: Like bulkheads but hollow, to maintain the fuselage shape
- Stringers: More lightweight versions of longhorns to take some load and transfer the rest to formers. Some are build into the inside of the skin
4
Q
What are the advantages of the Semi-monocoque fuselage design?
A
- Allow for the construction of streamlines and complex fuselage shapes
- Does not rely solely on the strength of a few things - if some damage there many be enough strength to hold together
5
Q
What is one of the main advantages of a non-metal material?
A
-The absence of corrosion
6
Q
How canyon reduce the amount of corrosion that a metal aircraft experiences?
A
- Regular washing
- Hangaring
- Avoiding damage to painted surfaces
- Treating internal structures with moisture excluding compounds
- Careful handling of hazardous materials
7
Q
What material is most likely to be corrosive to aircraft? What can happen?
A
Mercury
-Dramatic and instant reaction which destroys structural integrity
8
Q
What aircraft components may be susceptible to corrosion?
A
- Any metals
- Control cables
- Skin
- Structural members
- Engine components
- Propellers
- Electrical systems
9
Q
What is corrosion?
A
Loss of metal from the surface by chemical or electro chemical action. It is generally easily removed by mechanical action. Rust is an example of corrosion
10
Q
What are the different types of jet fuel? What are the differences?
A
Jet A: Common jet fuel in the United States. No kerosene blend.
Jet A1: Lower freezing point that Jet A. Most common jet fuel
Jet B: Also called wide cut, with low freezing and low flash points. 30% kerosene, 70% gasoline
JP5: High flash point for safety. Used on aircraft carriers
11
Q
What is jet fuel? Colour? Composition?
A
Liquid hydrocarbons, similar to Kerosene. Designed to mix at combustion temperatures and to flow at cold temperatures.
Not colour coded, all are a straw or clear colour.
12
Q
What are the different types of fuel tanks? Describe each?
A
- Integral: Wet wing, where the sealed structure becomes the tank
- Rubber/ Bladder: thin fabric impregnated with neoprene or other material that is impervious to fuel
- Rigid: Like the DA40, welded metal tank sits within the structure to hold the fuel. Usually Aluminium alloy
13
Q
What additions can be made to rigid tanks?
A
Cover in a shock resistant rubber that has self sealing capabilities.
14
Q
What features will normally be found in an integral fuel tank? What doe these things do?
A
-Baffles
Increase the strength and stop fuel surging
15
Q
What features are incorporated into fuel tanks to ensure that if there is fuel in the tank, that it will flow to the engine?
A
- Positive pressure head:
- Venting system to prevent cavitation
16
Q
What features are presented all types of fuel systems? Briefly describe each?
A
- Filler cap: Keep contaminants out of fuel, all for refuelling, easy to see if it locked
- Expansion space: Space for fuel to go beyond where it is when it is full at the cap. Allow space for fuel to expand if heated in the tanks
- Vents: Allow for release of pressure as fuel expands, allow for air to replace fuel to prevent cavitation
- Baffles: Increase strength and prevent fuel surging
- Sumps/Drains: Allow for heavy impurities to settle and and then be collected and sampled. Will create some unusable fuel
- Fuel quantity detectors: glass type, capacitance type
- Strainers/ Filters: Usually 3, to filter out imperfections
17
Q
How can the risk of water contamination in AVGAS and AVTUR fuels be reduced?
A
- Sump and drains
- Filling tanks at the end of day
- Standpipe
18
Q
How do drains work?
A
- Drain valve has a sealing poppet at the lowest point in each tank
- When depressed allows fluid at bottom of tank to be drain out, when released, seals
19
Q
What is the purpose of Fuel boost/aux pumps?
A
- Provide fuel for starting
- Purge the fuel lines of vapour to prevent the chances of vapour lock
- Prime cylinders of fuel injected engines
- Supply fuel if engine driven pump fails
- Fuel dumping
20
Q
What features does an auxiliary fuel pump have?
A
- Pressure relief valve
- Bypass valve (if vane type)
- Often submersible type to allow for all fuel to be used
21
Q
What powers the auxiliary fuel pump? What are the common types? Which is most common?
A
- Electrically driven
- Vane type
- Centrifugal type (most common)
22
Q
What is the purpose of a fuel cross-feed system? Why is it needed?
A
- To correct fuel balance differences
- Due to engines during at different rates, single engine operation, to allow fuel to be used by the other engine in engine out, Heaters/ APU only drawing from one tank, tank leakages
- Flexibility
23
Q
How are fuel tanks numbered?
A
Normally with their associated engine.
-No.1 on left, No4. on right
24
Q
What is vapour lock?
A
- Fuel vaporises in the fuel lines
- Vapour collects at a high point and prevents fuel from flowing past
- Will starve the engine of fuel
25
What causes vapour lock?
- Excessive heat build up
- Low pressure
- a combination of above
26
What should be done if vapour lock is encountered on engine start? (7)
- Boost pump on
- Mags turned off
- Full throttle and full rich mixture
- Turn the engine over on the started for a few seconds
- Check to see if fuel has started to flow from the carb
- Drain carb and let engine sit for 10 minutes
- Try a normal hot start
27
What are the advantages of hydraulic systems? (8)
- Gain mechanical advantage through use of different sized pistons
- Light weight for power output
- Easy instillation/ inspection
- Minimal moving parts (leads to less maintenance required)
- Cheaper (due to less lifetime maintenance costs)
- Transfer forces large distances
- Can use thin flexible pipes to transfer pressure
- Almost 100% efficient (small losses due to fluid friction)
28
What are the different types of hydraulic fluid? What colour are they?
- Vegetable base: Blue
- Synthetic: Purple
- Mineral base: Red
29
What are the characteristics of Vegetable based mineral hydraulic oil?
- Castor oil/ alcohol
- Older, less demanding hydraulic systems
- Compatible with natural rubber seals
- Can cause corrosion and form sludge
30
What are the characteristics of Mineral based hydraulic oil?
- Kerosene type chemical
- Good lubricating
- chemical prevent foaming and corrosion
- Little viscosity change with temp
- Flammable
- Requires synthetic rubber seals
31
What are the characteristics of Synthetic hydraulic oil?
- Withstand higher temps and pressures than mineral
- Not flammable
- Synthetic phosphate-ester oil
- Must be handled very carefully, to prevent water contamination
- Attacks certain plastics
- Requires synthetic seals
32
What different types of valves can be present in a hydraulic system?
- Check valve
- Pressure relief valve (thermal valve)
- Selector Valve
- Sequencing valve
- Shuttle valve
- By-pass valves
- Hydraulic fuses
33
What is a check valve? Dow to they typically work?
- Non return valve to prevent reverse fluid flow
- Spring loaded ball and seat inside a housing
- Fluid flow in normal direction compresses spring
- Fluid flow in opposite direction aids the spring and pushes ball against seat, sealing the system from reverse flow
* Can also be orifice type check valves*
34
What is a Pressure relief valve? How do they typically work?
- Limit the amount of pressure in parts of the system
- Also called a thermal valve
- Usually a simple spring loaded valve that is set to a certain pressure threshold
- When pressure limit is met, it will also for fluid to discard back to the reservoir or return line
35
What is a selector valve? How do they normally work?
- Used to control the direction of movement of a hydraulic actuating cylinder or other device
- Closed centre: rotating type, where 90˚ rotation either side of closed position will reverse the direction of the actuator
- Open centre: allows the hydraulic fluid to flow through it, even when it is not in a position to actuate a unit
36
What is a sequencing valve?
- Allows the operation of one hydraulic system to automatically set another one in motion
- eg. Landing gear doors must actuate before landing gear bogie.
37
What is a shuttle valve? How does it work?
- Valve to allow for alternate pressure source to feed the system.
- When pressure from normal inlet is less than backup emergency pressure, the shuttle will move across and allow for backup source to provide pressure.
- Position retaining ball will ensure that shuttle remains open to one source or the other
38
What is a bypass valve?
-Allow fluid to bypass a blocked component
39
What is a hydraulic fuse? How does it work?
- Safety device
- Installed to prevent total fluid loss in case of major downstream leak
- Spring will normally hold opening open, but when downstream pressure drops, the pressure will close the opening with a piston, preventing any more fluid loss
40
What is the purpose of an actuator?
-To convert the hydraulic pressure into a mechanical force to do useful work.
41
Describe the typical linear actuator?
- Fluid port on either end of a cylinder bore
- Piston with piston rod connected will move linearly to actuate a component
- Shuttle valve will direct fluid to appropriate end of cylinder
42
What are the different types of linear actuators? (5)
```
Single acting
Double acting (Balanced vs Unbalanced)
Tandem
Three port double acting
Servo Actuator
```
43
What is the function of an accumulator?
- Dampen pressure surges
- Aid or supplement pumps during Spinks on pressure demand
- Store pressure for limited operation after pump failure
- Compensate for small leaks
44
What is the principle of operation of the accumulator?
- Pressure vessel
- Divided into two parts by a flexible diaphragm or bladder, or a piston
- One part contains compressed air/nitrogen at half system design pressure
- when system is pressurised, gas compresses further and acts as a spring to provide reserve hydraulic pressure
45
What is a manual pump control valve? Why is it required?
- Valve that is automatically actuated or manually actuated
- Allows excess fluid in a system to flow back to reservoir when demand on the system is low
- Uses very little engine power as the pressure on the engine driven pump is low
- Must be closed before hydraulic actuation is required and opened afterwards
46
What checks can be done on the hydraulic system to ensure serviceability?
- Pre-flight inspection for leaks
| - Pressure gauge on gas side of accumulator
47
From the cockpit, how it be determined if the accumulator has had a leak?
- When system is shut off, the system pressure gauge should read the pre-charge pressure set..
- When system is shut off, the pressure should not immediately drop, but do so slowly as the accumulator provides some residual pressure
48
What system pressure does the high pressure pneumatic system produce? What is it used to actuate?
- 2900-3000psi
| - Flaps, spoilers, undercarriage retraction
49
What is done to remove moisture from the pneumatic system?
- Moisture remover does 98%
| - Dessicant does last 2% (changes away form blue colour when contaminated with water)
50
What pressure does the medium pressure pneumatic system operate around? What systems use this system?
50-150psi
- Air starters
- Pneumatic deicing boots
51
What are the requirements for a retractable leaning gear? (9)
- Support aircraft at max all-up-weight
- Absorb landing loads
- Withstand side loads
- Provide shock absorption
- Provide minimum rolling friction
- Minimum drag airborne
- Maximum traction for braking
- System to prevent accidental retraction
- Light as possible for given strength
52
What additions features may be incorporated into the retractable u/c of a heavy aircraft?
- Latches to allow for gravity extension
- Lockdown cams/ struts
- WOW solenoid switch to prevent ground retraction
- Electronic position indication system
- Warning for when landing configuration is detected but gear not extended
- Emergency lowering system (hand pump/ emergency accumulator for hydraulic pressure)
53
how are the landing gear doors and landing gear connected to reduce drag and allow for sequential operation?
- Sequencing valve ensures that gear doors opens first, then landing gear
- Doors will close when gear is fully up, or fully down, to reduce drag
54
How does the nose wheel steering on an heavy aircraft work?
- Small sterling wheel (tiller)
| - Activates some form of hydraulic, servo, mechanical or digital data (Fly-by-wire) transmission system
55
What are the 14 components of the Bogie undercarriage? What is their purpose?
- Pivot trunnion: Anchor to structure
- Trunnion beam: Allows pivot trunnion to pivot to retract
- Upper side brace: Braces lateral movement
- Lower side brace: Braces lateral movement
- Torque arms: Maintain for/aft alignment
- Pivot fork and shaft: Connects pivot beam to main strut
- Pivot beam (H member): Holds the wheels and axles
- Equaliser: Sets the pivot beam position for landing
- Axle: Hold each wheel
- Positioned: Hydraulic ram to set the pivot beam angle
- Wheels:
- Lower inner cylinder: Oleo strut (inner piston)
- Shock struct outer cylinder: Oleo strut
- Drag brace: supports/braces gear in fore/aft
56
What is a power brake? How does it work? What redundancy is built into the system?
- Pilot brake pedals actuate a brake control valves
- Brake control valves let in system pressure proportional to the pressure applied by the pilot
- Check valve and and accumulator hold pressure in case of hydraulic failure
57
Why are anti-skid brakes required? how doe they work?
- To achieve maximum braking on the verge of the skid, because the pilot will have no feel if the wheels have locked up
- AC generator in the wheel hub creates an electrical current, frequency proportional to the rotation of the wheels
- Anti-skid computer compares this to maximum allowable deceleration
- When rate is exceeded, signal is sent to anti-skid valve which releases pressure to brake unit involved
58
What is the purpose of the RADALT?
To indicate the actual height above the ground
59
What is the principle of operation of the FM RADALT?
- Continuous FM signal transmitted at varying frequency
- Sweeps 60MHz band between 4200-4400MHz (SHF band)
- Receiver detects phase difference between current signal being transmitted and received signal to calculate time
- Use principle of the known speed of light with time to modulate wave, to detect distance.
60
What errors are possible in a RADALT? What is its accuracy?
Fixed error: Frequency difference to heigh calculation is done in 5ft intervals, so an error of +/-2.5ft is possible
-Accurate down to 20ft, and +/-2ft or 2% up to 500ft
61
What are the limitations of the RADALT
- Surface reflectivity affects reading (Water best, soft fine soil worst, snow is difficult as to weather snow pack or underlying ground)
- Loss of lock between 2000-2500ft due to bank or surface below
62
Why have central warning panels being invented? What warnings can they give?
- Each system's warning used to be beside its control panel, but due to space and some panels being out of immediate view of pilots, they were centralised
- Can give visual, aural and tactile alerts
63
What is the function of the Master Warning system? In glass cockpits how does it work?
- To alert the crew to an operational problem, or system malfunction.
- Normally use visual, aural or tactile warnings to catch crew attention
- In glass cockpits, it is integrated into the system (Boeing: EICAS, Airbus: ECAM)
64
What are the different warning system alert levels? What does each mean?
- Time critical warnings: Associated with the primary flight path control, terrain or wind shear.
- Warnings: Alert crew to non-normal operation or system condition requiring immediate awareness and corrective action, engine fire, pressurisation
- Cautions: Alert crew to non-normal operation or system condition requiring crew alertness and action within a reasonable period of time, engine overheat, oil pressure, fuel state
- Alert/ Advisory: Require crew alertness and action only when time is available
65
If you get a master warning alert, how can the aural and visual cues be inhibited? What are the exceptions?
- Pushing the warning button will silence the aural alarm
- Light will remain illuminated until condition is resolved, or the reset switch is pushed
- Light will not extinguish if the warning is AP disconnect, T/O or LDG configuration, or overspeed
66
How can tactile alerts be inhibited?
- By correcting the unsafe situation
| - By a further tactile alert taking over (eg. stick pusher takes over from stick shaker)
67
What are the CWP systems that Airbus and Boing use?
Airbus: Electronic Centralised Aircraft Monitoring (ECAM)
Boeing: Engine Indicating and Crew Alerting System (EICAS)
68
What are the inputs of the MWWS?
- Pitot
- Static
- RADALT
- Vertical Gyro
- AoA transducer
- Flap position
69
What are the components the MWWS?
- Wind-shear computer
| - Integrated acceleration sensors
70
What are the inputs to the CPU of the GPWS?
- RADALT
- Vertical speed sensor
- Glidepath deviations
- Undercarriage position
- Flap position
71
What are the different GPWS modes? What does each mean? What aural alert will be heard?
1: Excessive rate of descent with respect to terrain. SINK RATE
2A: Excessive rate of terrain closure (not LDG config). TERRAIN TERRAIN
2B: Excessive rate of terrain closure (LDG config).
TERRAIN TERRAIN
3: Negative rate of climb after T/O or GA. DON'T SINK
4A: Unsafe terrain clearance (not LDG config, Gear up). TOO LOW - GEAR
4B: Unsafe terrain clearance (not LDG config, flaps up). TOO LOW - FLAPS
5: Excessive downwards departure form ILS glide slope. GLIDESLOPE
6: Descent below minimums. MINIMUMS
72
What is the warning envelope and aural warning that is heard for each GPWS mode?
```
1: 5-2450ft "Whoop Whoop - Pull Up"
2A: 50-1800ft "Whoop Whoop - Pull Up"
2B: 220-790ft "Whoop Whoop - Pull Up"
3: 50-700ft - No warning
4A: 50-500ft "Whoop Whoop - Pull Up"
4B: 50-500ft "TOO LOW - TERRAIN"
5: 100-500ft - No Waring
6: Selected MDA/DA - No Warning
```
73
What is the purpose of ACAS?
- To reduce the incidences of mid air collisions and near misses
- To provide alert information of conflicting traffic and warning of impending collision
74
What are the components of the ACAS system?
- Processor unit
- Two antenna (one above and one below)
- Mode S transponder
- Target must have Mode C transponder
75
What is the principle of operation of ACAS?
- ACAS equipped aircraft interrogates other transponder equipped aircraft, within a predetermined range
- Interrogation occurs on 1030MHz band several times per second to determine position
- Extrapolation of current range and altitudes differences, ACAS determines if threat exists
- Will give appropriate target indications and alerts to crew
76
What is the difference between TCAS I and TCAS II/ACAS II?
TCAS I: less capable, Only offers TA, do not require mode S
| TCAS II: Requires Mode s, Able to issue RA's and TA's. Larger warning range.
77
What is a Ring laser gyro? Why is it better than a gyro?
- Solid state device known as a rate sensor (similar to single axis gyro)
- Better because it has no moving parts
78
What is the principle of operation of the ring laser gyro?
- 2 coherent Lasers sent through a bore in a triangular/ square block, in different directions
- All corners have a mirror, one is semi-transparent to allow sense phase
- Coherent light has sine wave properties, when angular acceleration occurs there is phase difference in the light being detected
- This change in phase, and therefore frequency can be computed to detect angular acceleration over a measured time.
79
What is an INS/IRS? What is the difference between the two?
- Self contained, long range navigation system
- Provides a continuous and accurate fix of position
- Uses great circle navigation to provide very accurate steering commands to the AFDS
-INS was early system that did not compare its position solution with other aids. INS also tended to use gyro stable platform and mechanical gyroscopes to maintain its orientation
80
How does the INS maintain its integrity? What data can be input? Does/ can cross checking need to occur?
- No external Nav Aids required
- Automatics self alignment and calibration
- Continuous monitoring of its own performance
- Data can be input for present position, waypoints and destination
- Can be checked in flight against GPS/ ground aids
81
What is a gyro stable platform in an INS? How does it work? How does initial alignment occur?
- Platform holds accelerometers to measure acceleration in 3 different axis.
- Remote vertical gyros keep platform aligned in azimuth and to true north
- Gyros detect movement, and will generate signals to torque motors to maintain the platform orientation.
- Alignment occurs during initial synchronisation (called gyro compassing), and flight plan data cannot be entered until this is complete
82
How many accelerometers are required for an INS? with or without air data? In what directions do they sense?
- 1 in North/ South plane
- 1 in East/ West plane
- 1 in Vertical plane (not required if altimeter data is incorporated
83
What are the inputs to the INS? How is it interfaced with pilots and other systems?
Inputs:
- Own acceleration inputs
- ADC
Interface is through the FMS CDU
Displays information on EFIS
Coupled directly with the AFDS
84
What are the components of the flight data recorder system?
- Flight recorder panel
- Flight data acquisition unit
- Acoustic underwater locator beacon
- Flight data recorder
85
What powers the FDR and CVR?
The essential bus
86
What is the purpose of the CVR?
To record all cockpit conversations and sounds, either internally or externally (with ATC).
Records from FO mic, Captain mic, Cockpit area mic, and flight attendant intercom
87
How long must the CVR record for? When can it be erased/ not used?
- Legally must record last 30 minutes, most do 60 minutes. - recorded over itself after then
- Can be erased after WoW switch activated
- If CVR circuit breaker is pulled it will not record
88
What are the components of the CVR system?
- The recorder
- Control panel
- Ceiling mounted microphone
- Backup battery
- Circuit breaker
89
What is the purpose of the Altitude alerter? Who must have one?
-To prevent altitude/clearance busts from aircraft with high climb/descent abilities
Serves as a reminder of assigned altitude and gives warning to anticipate a level out
-Must be installed on all IFR aircraft
90
What is the principle of operation of the Altitude alerter ?
- CWP is linked via data busses or synchros to the ADC or RADALT.
- Visual and aural cures as preset altitude is approached
91
What is CAS? EAS? Mach No.? VMO? M(crit)?
EAS: Equivalent airspeed (corrected for compressibility)
CAS: Calibrated airspeed (corrected for position error)
Mach No: ratio of speed of an aircraft to the speed of sound in the same atmospheric conditions
VMO: maximum operating speed (Same as Vne)
M(crit): Critical mach number
92
Describe how a simple Machmeter works?
- Air dat instrument that combines the PoO of an ASI and ALT
- Incorporates a standard pressure altimeter capsule surrounded by a case of static pressure
- Inside the same case is an airspeed capsule, connected to the pitot source
- They respond in the normal way to changes in static and pitot pressure
- The two capsules interact with each other, the result of which is transferred to the indicator via a series of ricking shafts, levers and mechanical linkages
- The dial is calibrated to show mach number
93
What are the inputs of the ADC?
- AoA
- Static pressure source
- Pitot pressure source
- Total temperature source
94
What are the outputs of the ADC?
- ALT
- Vertical speed
- CAS
- TAS
- Mach
- VMO
- AoA
- TAT
- SAT
95
What systems can use ADC outputs?
- Primary flight instruments
- Flight director/ AFCS
- FMC
- GPWS/ TAWS/
- FDR
- Transponder altitude encoder
- CWP (waring systems)
96
How can crew test and edit information in the Air Data Computer
- Testing can be done by selecting the test function in the preflight
- Data cannot be edited within the ADC, unless by a technician
97
What is the purpose of the ADC?
-To convert raw air data into electrical outputs to represent that data, to be used in modern aircraft systems
98
What is the FMS? What is its purpose?
- Pilot interactive navigation computing and display system, providing fuel efficient aircraft operation together with navigational guidance reducing flight crew workloads
- Assist flying the aircraft with maximum economy and safety to a previously planed and defined route, both laterally and vertically
99
What displays are given to pilots as part of the FMS?
- Map/ route data on navigational display
| - Command markers on the airspeed, altitude and thrust markings to aid in flying efficient profiles
100
What is the FMC? What can it do? What data does it use?
- Flight management computer
- Uses flight crew entered data, systems data and FMS nav database to calculate present position and pitch, roll and thrust commands required to fly optimum route
- Sends these commands to auto-throttle, AFDS and Auto-pilot.
101
What type of navigation is the FMS certified for?
- RNAV when used with GPS or radio updating
- Able to do RNAV(RNP) approaches
- Supplement all other types of approaches (help with VOR/DME/ILS
102
What are the components of the FMS? What systems can the FMS provide commands to?
- Flight management computers
- CDU's
- Auto-pilot flight director system
- Thrust management (auto-throttle)
- IRS
103
What does FANS stand for?
Future air navigation system
104
What are the main components of an aircraft?`
- Semi-monocoque fuselage
- Main plane
- Tail plane and fin
- Landing gear
- Powerplant(s)
105
What are the main structural components of a wing?
- Wing spar
- Wing rib
- Stringers
- Skin
106
What are the different types of fuel quantity indicating gauges? How does each work?
- Float diven pinter
- Float driven rod
- Electrical ratiometer (DC current)
- Electronic capacitance type
107
What is the principle of operation of the electronic capacitance type fuel indicator?
- Electronic capacitors installed in the fuel tanks
- Air and fuel have different capacitance values
- Capacitance of all probes the tank are totalled and compared in a bridge circuit by a microprocessor, which displays fuel indication
- Capacitance varies with capacitor surface area, distance between two and the dielectric constant of the fluid between. (only fluid level changes)
- Capacitance varies with temp/density so a compensator is included that will always be covered in fuel
- System is calibrated to indicate fuel mass
108
What are the different types of Rotary Hydraulic actuators?
- Piston type
- Vane type
- Rack and pinion type
109
How many parameters can the FDR record?
48-300
110
What is the relationship between height AGL and the frequency shift in the RADALT?
Frequency changes by 40 Hz per foot
| Not MHz
111
What is the principle of operation of the pulse modulation RADALT?
- Operate at 1600MHz
- Uses echo principle
- Emits signal, and times the duration for it to reach the surface and return
- Performs calculation with known speed and measured time to determine distance
