Instrumentation, Navigation & Instrument Aids Flashcards
What are inherent errors with the altimeter?
- Position error (pitot-static error)
- Scale error (manufacturing error; a true 1,000ft reads 1,100ft on altimeter)
- Mechanical error (slippage in gears in aneroid itself)
- Density error
- Hysteresis (material error in aneroids, some material cause friction and error)
- Reversal error(abrupt or rapid altitude changes; only momentary)
P SMD H R!
What are performance instruments?
Information relating to the performance of an aircraft. It is determined by the airspeed indicator, altimeter, vertical speed indicator, heading indicator, magnetic compass and turn coordinator/bank indicator.
- Airspeed indicator
- Altimeter
- Turn-coordinator
- Heading indicator
- Vertical speed indicator
- Magnetic compass
What are control instruments?
Information relating to the aircrafts’ attitude and power settings.
- Attitude indicator
- Tachometer (power control gauge)
What effects are altimeters subject to?
- Effect of mountains (due to down or upslope winds which change your airspeed, and subjects itself to Bernoulli’s principle of pressure (fast wind=low pressure=higher altimeter reading, vice versa)
- Downdrafts or turbulence occurs usually in mountain regions)
- Pressure drop (the drop in pressure when flying through areas of high windspeed)
When departing on a runway heading SID, is the heading flown take into account wind correction?
No!
What are the standard holds regarding altitude and time?
1 minute outbound under 14,000’ MSL
1 1/2 minutes outbound over 14,000’ MSL
What are the three types of entrys into a holding patern?
Direct entry, offset entry, parallel entry.
When a MSA (minimum sector altitude) is posted and there is no established radius, what does it revert to?
25NM.
Operation of GNSS:
Global Navigation Satellite System (GNSS)
Uses one or more satellites, aircraft receivers and system integrity monitoring to determines time and position
PRECISE TIMING AND POSITION TRIANGULATION.
Operation of GPS:
Based on satellite ranging. It is determined by measuring distance by precise timing from a of satellite using the aircraft’s GPS’ system clock.
Needs at least 4 satellites!
IFR instrumentation requirements:
A - Attitude indicator A - Alternate static source V - Vacuum pressure indicator V - Vertical speed indicator O - Outside temperature gauge P - Pitot-static anti-icing S - Sufficient two-way radio communication S - Sufficient radio navigation equipment where applicable
AAVVOPSS
IFR equipment requirements for safety:
- Fire extinguisher
- Updated navigation charts for any probable divisionary route
- Timepiece
What are the ground-based navigation systems?
- ADF
- VOR
- ILS
- DME
- VORTAC
NDB errors:
- Night effect (remember LF/MF “sun up freq up”)
- Mountain effect
- Quadrantal/banking error
- Coastal effect (over the sea, water bends the NDB signal)
- Electrical storms
- Icing and sleet
- Precipitation static
NEMPICQ
- Night effect
- Electrical storms
- Mountain effect
- Precipitation static
- Icing and sleet
- Coastal effect
- Quadrantal effect
How do you calculate the closing angle to re-intercept your track after going over half the distance?
Closing angle = Distance off × 60 ÷ Distance to go
How do you calculate range to a VHF facility?
Range = (1.25 × √indicated altitude) + (1.25 × √altitude of station)
What is the required accuracy when testing your VOR instrument using the dual VOR test?
+/- 4 degrees.
What is the required accuracy when testing your VOR instrument using he airborne geographical location check?
using he airborne geographical location check?
+/- 6 degrees.
How do you calculate time to an NDB?
time (IN SECONDS) / degrees of relative bearing change = Time to NDB (minutes)
How do you calculate distance to NDB?
(Groundspeed × time to NDB (IN MINUTES)) / 60 = Distance to NDB (NM)
What is scalloping?
A sudden fluctuation of the cockpit indicators.
Caused by blocked signals like terrain and is normally very short.
BE AWARE OF SCALLOPING WHEN PLANNING OFF-AIRWAY NAVIGATION!
On the CDI and/or HSI, what does each dot represent on either side of the centerline?
2 degrees, total of 10 degrees EITHER side of the CDI.
When tuned to an ILS, each dot represents 0.5 degrees!
What is the thickness of the glideslope transmitter beam?
1.4 degrees thick.
What is an LP approach?
Localizer Performance ( LP ) approaches are non-precision approaches with Wide Area Augmentation System ( WAAS ) lateral guidance.
LP = WAAS
In order to get a position fix using LORAN, at least __ stations are required.
3 total stations!
A master then two secondary stations.
LORAN works in the ____ frequency range.
Low (LF) range.
LOng RANge navigation!
What are the three types of augmentation systems for GPS?
- ABAS (aircraft based augmentation system)
- SBAS (satellite based augmentation system)
- GBAS (ground based augmentation system)
What are the alert limits for Receiver Autonomous Integrity Monitoring (RAIM)?
- 2 NM en route
- 1 NM terminal
- 0.3 NM non-precision approach
If the RAIM system cannot maintain integrity and it passes these limits, RAIM will alert the pilot and look for a way to resolve it. Pilot must not use GNSS approaches when this occurs.
What is an fault detection and exclusion system (FDE)?
It is like RAIM, except that it is more specific; it figures out what satellite is faulty and then excludes it from the navigation solution. Allows you to continue using GPS in spite of a failed satellite.
All WAAS-enabled receivers have FDE.
Needs at least 6 satellites to function!
What is WAAS (Wide Area Augmentation System)?
Uses a network of ground-based stations that monitor satellite signals and sends it to a master for validation, then corrects its errors.
What are continuous/analog instruments?
An aircraft instrument that is circular and is served by a single pointer (i.e. six-pack).
What is a symbolic/qualitative instrument?
Data is presented in pictorial or symbolic format (i.e. HSI or attitude indicator).
What is a pictorial instrument?
Displays information visually to gain a better picture of the outside world. This is usually found on the EFIS or PFD.
What is a situation information instrument?
General orientation of the aircraft (i.e. attitude indicator).
What is a command information instrument?
An instrument where the pilot is directed to the next course of action, such as a error that must be rectified. These are usually found in GPS or FMS.
What is a status information instrument?
Data that the pilot is not directly concerned with, such as the fuel gauge.
Quantitative instrument reading:
Determining the exact numerical value, like an altimeter.
Qualitative instrument reading:
Judging the approximate value such as a subtle change in the altimeter.
How does the airspeed indicator work?
It reacts to changes between the pitot air and static air.
When are airspeeds most greatest?
In slow speeds; position error is noticeable.
How are V-speeds on the airspeed indicator expressed?
They are expressed as calibrated airspeed. However, some typical gauge errors may prevail.
How are the colours on a typical airspeed indicator coordinated?
White: flap operating range
Green: normal operating range
Yellow (caution) smooth air cruising range
Red: never exceed
How is an indication of feet above sea level possible?
By setting the local altimeter.
An aircraft should not have an error of more than ____ when compared to ground elevation at a known aerodrome.
50ft.
What are the initial altimeter certification limits?
+/- 20ft at sea level
+/- 230ft at 40,000ft
What happens when an aircraft flying in a mountainous region encounters a downdraft?
- Aircraft descends
- Rate of climb indicates a brief climb
- Altimeter will indicate a brief rate of climb
Altimeter could over-read by as much as 3,000ft
With a servo/pneumatic altimeter, you should check the following before flight:
- Set local barometer
- Check computer-indicator +/- 50ft of known aerodrome elevation
- Select servo/pneumatic RESET mode
- Check +/- 50ft on outer-scale, +/- 40ft on computer indicator
- Select servo/pneumatic STBY mode
- Check +/- 50ft of known elevation
What are the two functions of the VSI?
Trend instrument
Rate instrument
What two inherent system errors are found on Central Air Data Computers (CADC)?
- Position error
2. Scale error (instrument error, aneroids)
How do you calculate range to a VHF facility?
Range = (1.25 × √indicated altitude) + (1.25 × √altitude of station)
Operating principle of VOR:
A phase difference between 2 transmitter signals.
What is the accuracy course alignment for published VORs?
+/- 3 degrees FOR ALL PHASES OF FLIGHT.
Disadvantages of VOR:
- Station overlap at high altitudes
- Line of sight error
- Shadow effect (obstructions)
What is the VOR receiver check tolerance?
+/- 4 degrees for air AND ground.
What is the VOR check tolerance voer a landmark?
+/-6 degrees of published radial.
What is the operating principle of an NDB:
Radiates a signal in ALL directions.