AC 90-92 2/5/93 Appendix 1
LORAN-C OCEANIC COVERAGE DIAGRAM Norwegian Sea Chain - 7970
ID TRANSMITTER POWER (KW) PARAMETERS M Ejde 400 • Contour: SNR -10 db; GDOP 7,700 ft/us W Bø 165 • Average Atmospheric Noise: 61 db
• Surface to FL 600 Sylt 215 Y Sandur 1500 • Flight Verified Z Jan Mayen 165 50° 45°
AC 90-92 Appendix 1 2/5/93
LORAN-C OCEANIC COVERAGE DIAGRAM Mediterranean Sea Chain - 7990
TRANSMITTER POWER (KW PARAMETERS M Sella Marina 165 Contour: SNR -10 db; GDOP 7,700 ft/us Lampedusa 400 • Average Atmospheric Noise: 60 db Surface to FL 600 Y Kargabarun 165 Computer Generated L Estartit 165 55° 50° 45° 40° 35° 30° 25° 20° W 35° 0° 10° 15° 20° 25° 30° 12
AC 90-92 2/5/93 Appendix 1
LORAN-C OCEANIC COVERAGE DIAGRAM Saudi Arabia (North) Chain - 8990
ID TRANSMITTER POWER (KW) PARAMETERS M Afif 800 • Contour: SNR - 10 db; GDOP 7,700 ft/us V Salwa 800 • Average Atmospheric Noise: 65 db
• Surface to FL 600 W Ar Rugi 200 Computer Generated Ash Shaykh Humayd 400 Y Al Lith 200 Z Al Muwassam 800 40° 35° 30° 25° 20° 10° E 35° 40° 50° 13
AC 90-92 Appendix 1 2/5/93
LORAN-C OCEANIC COVERAGE DIAGRAM Saudi Arabia (South) Chain - 7170
ID TRANSMITTER POWER (KW PARAMETERS M Al Khamasin 800 • Contour: SNR -10 db; GDOP 7,700 f/us W Salwa 800 • Average Atmospheric Noise: 65 db Afif 800 • Surface to FL 600
• Computer Generated Al Lith 200 Z Al Muwassam 800 40 35° 30° 25° 20° 15° 10° 45° 50° 14
AC 90-92 2/5/93 Appendix 1
LORAN-C OCEANIC COVERAGE DIAGRAM East Asia Chain - 5970
TRANSMITTER POWER (KW) PARAMETERS M Pohang 35 • Contour: SNR -10 db; GDOP 7,700 ft/us W Hokkaido 600 • Average Atmospheric Noise: 60 db Hampyong 35 • Surface to FL 600 Y Gesashi 600 • Computer Generated 55° 50° 45° 40° 35° 30° 25° 20°% E 115° 145° 120° 125° 130° 135° 140° 15
AC 90-92 Appendix 1 2/5/93
LORAN-C OCEANIC COVERAGE DIAGRAM Northwest Pacific Chain - 9970
ID TRANSMITTER POWER (KW) PARAMETERS M Iwo Jima 1815 • Contour: SNR - 10 db; GDOP 7,700 ft/us W Marcus Island 1050 • Average Atmospheric Noise: 60 db
• Surface to FL 600 Hokkaido 600 Y Gesashi 600 • Computer Generated Z Barrigada 600 15° 10° 5° 0° E 115° 120° 125° 130° 135° 140° 145° 150° 155° 160° 16
Appendix 1
LORAN-C NAS COVERAGE DIAGRAM Alaska - North Pacific Chain - 9990
ID TRANSMITTER POWER (KW) PARAMETERS M Saint Paul 270 • Contour: SNR - 10 db; GDOP 7,700 ft/us Attu Island 270 • NAS GDOP 4,200 ft/us Y Port Clarence 1000 • Average Atmospheric Noise: 53 db Z Narrow Cape 400 • Surface to FL 600
• Flight Verified 75° 70° 65° 60° 55° 50° 45° M 40° 35° 160° 165° 125° 170° 130° 175° 180° 175°W 170° 135° 165° 160° 155° 150° 1450 140° 17
AC 90-92 CHG 1 Appendix 1 6/15/93
LORAN-C NAS COVERAGE DIAGRAM Alaska - Gulf of Alaska Chain - 7960 ID M TRANSMITTER POWER (KW) Tok 540 • Contour: SNR - 10 db; GDOP 7,700 ft/us PARAMETERS • NAS GDOP 4,200 ft/us Narrow Cape 400 • Average Atmospheric Noise: 53 db Y Shoal Cove 540 • Surface to FL 600 Z Port Clarence 1000 • Flight Verified 75° 70° 65° 60° 55° 50° 45° 40° 35° E 160° 125° 165° 130° 170° 175° 180° 175°W 170° 165° 160° 1550 150- 1450 190- 135° 18 *U.S. G.P.D.: 1993-343-273:80076
AC 90-92 2/5/93 Appendix 2 APPENDIX 2. GLOSSARY Accuracy -- In navigation, the accuracy of an estimated or measured position of a craft (vehicle, aircraft, or vessel) at any given time is the degree of conformance of the measured position with the true position of the craft at that time. Since accuracy is a statistical measure of performance, a statement of the accuracy of a navigation system is meaningless unless it includes a statement of the applicable uncertainty in position (see statistical measure of accuracy).
Airplane Flight Manual (APM) - Means FAA-approved AFM. This entire document is FAA approved and must be carried on all aircraft certificated under FAR Part 25. The AFM contains flight manual supplements for operating specialized equipment installed in the aircraft, such as Loran-C, as well as operating procedures and limitations for the airplane.
The AFM must be readily accessible to the flightcrew during all operations. Aircraft operating under FAR Part 121 may carry an aircraft operating manual (ACOM) in lieu of the Air Traffic Service Route (ATSR) -- Many ATSR's are over the water and beyond the 12 nm limit. The term "ATS Route" by ICAO definition is used to mean at least the following: airway, advisory route, controlled or uncontrolled route. An ATSR is a designated route and may or may not have a published identifier. Part 121 and Part 135 operators should consult their operations specifications (OpSpecs) for specific route approval.
Ambiguity -- System ambiguity exists when the navigation system identifies two or more possible positions of the aircraft, with the same set of measurements, and no indication of which is the most accurate position. The pilot should be aware of potential system ambiguities and should be ready to identify and resolve the ambiguity within safe limits.
Appropriate Authority -- Regarding flight over the high seas, the relevant authority is the state of registry. Regarding flight over other than the high seas, the relevant authority is the state having sovereignty over the territory being overflown.
Appropriate NAVAID'S - Ground- or space-based NAVAID's that can be used along any given route. Standard, ground-based, ICAO NAVAID's include VOR, VOR/DME, and NDB's. Range is limited to their standard service volume or, if flight checked, to their extended service volume.
AC 90-92 Appendix 2 2/5/93 Area Navigation (RNAV) -- A method of navigation which allows pilots to establish and maintain a flight path on any chosen course within the coverage area of the type of navigation sources being used. RNAV utilizing capabilities in the horizontal plane only is called 2D (two dimensional) RNAV, while RNAV which also incorporates altitude positioning is called 3D. Time navigation (TNAV) may be added to either 2D or 3D systems. TNAV added to a 3D system is called 4D.
Availability -- The availability of a navigation system is the percentage of time that the pilot may use the services of the system within a specified coverage area. Signal availability is the percentage of time that navigation signals transmitted from external sources are available for use. Operational availability is a function of both the physical characteristics of the environment and the technical capabilities of the transmitter facilities.
Baseline Extension -- The extension of a line between two or more Loran-C stations.
Loran-C accuracy is severely degraded (to non-existent) along a baseline extension (see figure 9).
FIGURE 9
BASELINE EXTENSION 600 CENTERLINE Y COORDINATE (NAUTICAL MILES) 400 200 BASELINE
EXTENSION
BASELINE
EXTENSION
BASELINE -600 -600 -400 -200 200 400 600
X COORDINATE (NAUTICAL MILES)
AC 90-92 2/5/93 Appendix 2 Bonding -- Bonding, in Loran-C navigational installations, is the electrical connection of control surfaces to an airframe component. One example of bonding is the use of metal braid to connect and secure P-static wicks to a control surface.
Capacity -- The number of users that a system can accommodate simultaneously.
Class I Airspace -- Short-range navigation within the limits of the operational service volume of ground-based NAVAID's.
Class II Airspace -- Long-range navigation beyond the limits of the operational service volume of ground-based NAVAID's.
Coast-Out Fix -- A navigation aid or intersection, sometimes called a coastal fix or gateway fix, for aircraft transitions between the domestic and oceanic route structure, such as an Organized Track System (OTS) or air traffic service volume of ICAO standard NAVAID's.
Colored Airway -- An oceanic ATS route that is predicated on either low/medium frequency or VHF NAVAID's. For example, A646 is "Amber 646," B636 is "Blue 636," R540 is "Red 540," G528 is "Green 528." In some countries, the phonetic alphabet is used in lieu of colored airway designations such as Alpha (in lieu of Amber) and Bravo (in lieu of Blue).
Some colored airways in the Gulf of Mexico are referred to as "Gulf Routes."
Coverage - The coverage provided by a radio navigation system is that surface area or space volume in which the signals are adequate to permit the user to determine position to a specified level of accuracy. Coverage is influenced by system geometry, signal power levels, receiver sensitivity, atmospheric conditions, surface conductivity, and other factors affecting signal availability.
Critical Triangle Method -- The use of three independent navigation systems so that if any two systems are in disagreement with each other, then the third system can be used to determine which one of the two other units is in error.
Cross-Track Error - The perpendicular deviation of the aircraft to the left or right of the desired track.
Dead Reckoning (DR) -- A method of estimating the position of an aircraft or radio aids, based upon a previous known position and an estimate of the course and distance travelled within a given time increment. An estimation of the winds and temperatures aloft is an integral part of the DR process. An alternative definition is that DR is navigation of an 3
AC 90-92 Appendix 2 2/5/93 aircraft solely by means of computations based on true airspeed, course, heading, wind direction and speed, groundspeed, and elapsed time.
Decibel (db) - A decibel is a unit of relative power, voltage, or current, plotted on a logarithmic scale. An increase (or decrease) of 3 db means that power is either double (or half) of the original value. Decibel is used to compare one relative value to another.
Domestic Airspace - Airspace overlying the continental land mass of the United States, including Alaska, Hawaii, and U.S. possessions. Domestic airspace extends to 12 nm offshore.
En Route -- A phase of navigation covering operations between departure and arrival terminal phases.
Entry Point - The point at which an aircraft transitions from an offshore control area to oceanic airspace.
Extended Over-Water - FAR Part 1 defines "extended over-water operation" for aircraft as an operation over-water at a horizontal distance of more than 50 nm from the nearest shoreline; and for helicopters, as an operation over-water at a horizontal distance of more than 50 nm from the nearest shoreline or more than 50 nm from an offshore heliport structure.
The term "extended over-water operations" is used in defining the kinds of radio equipment required for navigation for flight operations conducted under FAR Parts 121, 125, and 135 (see over-water for FAR Part 91 requirements).
Extended Service Volume -- Defines the reception limits of VOR/DME and NDB NAVAID's which are usable for unpublished route navigation and which are flight checked to confirm these limits of coverage. The extended service volume of NDB's used in oceanic navigation (such as beyond the 75 nm standard service volume) must be individually flight checked. There is no procedure readily available to pilots to help them determine whether or not a particular charted offshore route has an extended service volume. However, air traffic separation is based on DR beyond the extended service volume, so the pilot uses the NAVAID for as long as possible, establishes the wind drift rate, then uses LRN or DR.
Final Approach Fix (FAF) -- The point at which the last segment of an instrument approach commences. The final approach is the segment between the FAF (or point) and the runway, airport, or missed approach point (MAP).