AVIONICS PPT 6

Advance Aircraft Navigation

Instrument Landing System

is a precision runway approach aid employing two radio beams to provide pilots with vertical and horizontal guidance during the landing approach

Localizer (LOC)

provides horizontal guidance to an approaching aircraft.

Glideslope (GS)

defines the correct vertical descent profile.

Instrument Landing System

operates as a ground-based instrument approach system that provides precision lateral and vertical guidance to an aircraft approaching and landing on a runway.

Radio signals; High Intensity Lighting Arrays

Instrument Landing system uses a combination of and in many cases, to enable a safe landing during instrument meteorological conditions (IMC), such as low ceilings or reduced visibility due to fog, rain, or blowing snow.

Beam Systems

consists of a radio transmitter that was connected to a motorized switch to produce a pattern of Morse code dots and dashes.

Localizer, Glideslope, Marker Beacon, Approach Light System

ILS Components

Localizer (LOC)

is an antenna array normally located beyond the departure end of the runway and generally consists of several pairs of directional antennas.

Azimuth Navigation Information

The Localizer generates and radiates signals to provide final approach __ to landing aircraft.

90-Hz and 150-Hz

The Localizer generates and radiates signals to \n provide final approach azimuth navigation information \n to landing aircraft. The antenna sends a VHF carrier \n signal with and sideband signals that \n the aircraft instruments determine as left and right of \n the centerline.

cockpit indicator

The aircraft interprets the signal and displays them on the guiding the pilot until the runway is in sight.

Glideslope

sends a UHF carrier signal with the same two 90-Hz and 150-Hz sideband frequencies that aircraft instruments determine as above or below the desired glide path.

50ft; 3 Degree; 500 feet per minute

The GS aerials are usually located so that the glide-slope provides a runway threshold crossing height of \n about This is approximately above horizontal (ground level) to remain above obstructions and \n reach the runway at the proper touchdown point which gives the aircraft a descent rate of \n approximately .

1000 feet

The glide slope is normally positioned after the approach end of the runway.

Marker Beacon

These are vertically broadcast radio signal that indicate distance from runway and are more sensitive (narrower broadcast vertical cone) closer the runway.

Approach Light System (ALS)

provide the basic means to transition from instrument flight to visual flight for landing.

2400-3000 feet; 1400-1500 feet

ALS are a configuration of signal lights starting at the landing threshold and extending into the approach area a distance of for precision instrument runways and for non precision instrument runways

White crossbars, 100 ft wide

Tell approaching pilots whether the aircrafts wings are level for touchdown.

Sequenced Flashing light

Some Systems include which appear to the pilot as a ball of light traveling towards the runway at high speed.

Sequence Flashers

lines of white strobe lights, illuminate in sequence to guide the pilot’s eye towards the runway centerline.

Red approach lights

mark an undershoot zone 1,000 ft. long in which approaching aircraft should not land.

Approaching Lights; 200 ft.

vary in height with the lie of the ground. on low-lying terrain they may be as high as . They have frangible stems that snap off if accidentally hit.

Threshold lights

may be bidirectional showing green to pilots landing and red on the reverse side, marking the runway end for pilots taking off.

Visual Approach Slope Indicator (VASI)

is a of lights so arranged to provide visual descent guidance information during the approach to a runway. These lights are visible from 3-5 miles during the day and up to 20 miles or more at night.

plus or minus 10 degrees; 4 NM

The Visual Glide Path of the VASI provides a safe obstruction clearance within___ of the extended runway centerline and to ______ form the runway threshold.

Below Glidepath

Far bar - Red

Near Bar - Red

On Glidepath

Far Bar - Red

Near Bar - White

Above Glidepath

Far Bar - White

Near Bar - White

Precision Approach Path Indicator (PAPI)

uses light units similar to the VASI but are installed in a single row of either two or four light units. Theses lights are visible from about 5 miles during the day and up to 20 miles at night.

plus or minus 10 degrees; 3.4 NM

The visual glide path of the PAPI typically provides safe obstruction clearance within of the extended runway centerline and to from the runway threshold.

ILS critical areas and ILS sensitive areas

are established to avoid hazardous reflections that would affect the radiated signal. The locations of these critical areas can prevent aircraft from using certain taxiways leading to delays in takeoffs, increased hold times, and increased separation between aircraft.

Localizer systems

• are sensitive to obstructions in the signal broadcast area, such as large buildings or hangars.

Glide slope systems

• are also limited by the terrain in front of the glide slope antennas. If terrain is sloping or uneven, reflections can create an uneven glidepath, causing unwanted needle deflections.

Category I

Decision Height : > 200 ft (60 cm)

RVR: >550 m (18000 ft ) or visibility > 88m (2600 ft)

Category II

Decision Height: 100-200 ft (30-60m)

RVR: ICAO: > 350 m (1200ft)

       FAA/JAA(EASA) : >300m (1000ft)

Category III A

Decision Height: < 100 ft (30 cm)

RVR: >700ft (200m)

Category III B

Decision height: <50 ft (15m)

RVR: ICAO/FAA: 150-700ft (50-200m)

JAA(EASA): 250-700ft (75-200m)

Category III C

Decision Height: no limit

RVR: none

Microwave Landing System (MLS)

is an all-weather precision radio guidance system intended to be installed at large airports to assist aircraft in landing including blind landings. It has numerous operational advantages over ILS such as wider selection of channels to avoid interference with nearby installations, excellent performance in all weather, a small "footprint" at the airports, and wide vertical and horizontal "capture" angles that allowed approaches from wider areas around the airport.

Inertial Navigation System (INS)

referred to a self-contained navigation system utilizing a gyro-stabilized platform for dead-reckoning, and with a pilot interface allowing a limited number of waypoints to be entered and basic navigation information to be displayed.

Inertial Navigation

is a form of “Dead-Reckoning” that relies on accelerometers and gyroscopes to detect acceleration and velocity respectively along 3 perpendicular axes. An approximate 2 or 3 dimensional position can be constantly determined in relation to a known starting point, velocity and orientation.

Inertial Reference Unit (IRU)

• It refers to a computer that integrates Inertial Reference System (IRS) outputs and provides inertial reference outputs for use by other \n navigation and flight control systems, including the Flight Management System (FMS).
• is like a modern, automated, dead-reckoning device.
• works on basis of latitude/longitude, so it is \n independent of magnetic North; it is considered as true location.
• Use accelerometers and gyros to track changes in acceleration and direction.

Global Navigation Satellite System (GNSS)

is a general term describing any satellite constellation that provides positioning, navigation, and timing (PNT) services on a global or regional basis.

GPS

is the most well known type of GNSS

GALILEO

1st satellites launched in October,2011 Operational in 2014 operational worldwide targeted - 2019

COMPASS (Beidou-2)

1st satellite launch 2007 Operational in Asia-pacific late 2012; Operational worldwide targeted for - 2020

GLONASS

Operational last of 24 satellites restored worldwide coverage October 2011.

Global Positioning System (GPS)

is a U.S. -owned utility that provides users with positioning, navigation, and timing (PNT) services.

Space Segment; Control Segment; User Segment

GPS three segments

Global Positioning System (GPS)

is a satellite based radio navigation system which utilizes precise range measurements from GPS satellites to determine precise position anywhere in the world.

Twenty four (24); 24 in hour

In satellites operated by USAF provide ___ , all weather, global coverage.

atomic clocks

Satellites are equipped with __

Minimum of four (4)

_ satellite signals enable receivers to \n triangulate position and time.

passive

the system of GPS is , it allows for unlimited number of users.

Performance Based Navigation (PBN)

• is comprised of Area \n Navigation (RNAV) and Required Navigation Performance (RNP) \n and describes an aircraft's capability to navigate using \n performance standards.
• in simple terms, redefines \n the aircraft's required navigation capability from sensor \n (equipment) based to performance based. The foundation for \n Performance Based Navigation is area navigation or RNAV.
• defines performance requirements for aircraft navigating on \n an Air traffic service route (ATS) route, on a terminal or on an \n approach procedure.

Area Navigation (RNAV)

is a method of navigation that permits aircraft operation on any desired flight path within the coverage of ground or space based navigation aids, or within the limits of the capability of self-contained aids, or a combination of these.

Required Navigation Performance (RNP)

is a family of navigation specifications under Performance Based Navigation (PBN) which permit the operation of aircraft along a precise flight path with a high level of accuracy and the ability to determine aircraft position with both accuracy and integrity.