{"id":2674,"date":"2024-09-25T17:59:55","date_gmt":"2024-09-25T17:59:55","guid":{"rendered":"https:\/\/crp.trb.org\/acrpwebresource20\/glossary\/"},"modified":"2024-09-25T19:21:21","modified_gmt":"2024-09-25T19:21:21","slug":"glossary","status":"publish","type":"page","link":"https:\/\/crp.trb.org\/acrpwebresource20\/glossary\/","title":{"rendered":"Glossary"},"content":{"rendered":"<div data-elementor-type=\"wp-page\" data-elementor-id=\"2674\" class=\"elementor elementor-2674\" data-elementor-post-type=\"page\">\n\t\t\t\t<div class=\"elementor-element elementor-element-4a6a6645 e-flex e-con-boxed e-con e-parent\" data-id=\"4a6a6645\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-6f1b0376 elementor-widget elementor-widget-image\" data-id=\"6f1b0376\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img decoding=\"async\" src=\"https:\/\/crp.trb.org\/acrpwebresource20\/wp-content\/uploads\/sites\/40\/2024\/09\/09-22-airfileld-electrical-banner.jpg\" title=\"09-22-airfileld-electrical-banner\" alt=\"09-22-airfileld-electrical-banner\" loading=\"lazy\"\/>\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-334b15a1 e-flex e-con-boxed e-con e-parent\" data-id=\"334b15a1\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-30b92ed6 elementor-widget elementor-widget-heading\" data-id=\"30b92ed6\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h2 class=\"elementor-heading-title elementor-size-default\">Key Terminology<\/h2>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-137489e1 e-flex e-con-boxed e-con e-parent\" data-id=\"137489e1\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-4adf57b4 glossary-list elementor-widget elementor-widget-text-editor\" data-id=\"4adf57b4\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<ul><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Approach Lighting System (ALS)&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Lighting system located at the approach end of a runway consisting of a series of light bars, strobe lights, or a combination of the two, which extend outward from the runway end.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Approach Lighting System (ALS)<\/span><\/strong> &ndash; Lighting system located at the approach end of a runway consisting of a series of light bars, strobe lights, or a combination of the two, which extend outward from the runway end.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Arc Blast&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Tremendous temperatures of the arc cause the explosive expansion of both the surrounding air and the metal in the arc path. Dangers associated with arc blast include high pressure, sound, and shrapnel.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Arc Blast<\/span><\/strong> &ndash; Tremendous temperatures of the arc cause the explosive expansion of both the surrounding air and the metal in the arc path. Dangers associated with <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Arc Blast&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Tremendous temperatures of the arc cause the explosive expansion of both the surrounding air and the metal in the arc path. Dangers associated with arc blast include high pressure, sound, and shrapnel.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>arc blast<\/span> include high pressure, sound, and shrapnel.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Arc Flash&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Electric current passes through air between ungrounded conductors or between ungrounded conductors and grounded conductors.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Arc Flash<\/span><\/strong> &ndash; Electric current passes through air between ungrounded conductors or between ungrounded conductors and grounded conductors.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Base Can&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;In-ground metal enclosure that supports a lighting fixture, houses its electrical components, and facilitates future maintenance.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Base Can<\/span><\/strong> &ndash; In-ground metal enclosure that supports a lighting fixture, houses its electrical components, and facilitates future maintenance.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Beacon&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Installed at an airport or aeronautical facility to indicate location and facility type to aircraft pilots at night. This device is mounted on top of a towering structure above other airport buildings.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Beacon<\/span><\/strong> &ndash; Installed at an airport or aeronautical facility to indicate location and facility type to aircraft pilots at night. This device is mounted on top of a towering structure above other airport buildings.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Cramp&rsquo;s Helipad Approach Path Indicator&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;A visual aid to pilots ensuring a safe approach path. Can be installed at airports or heliports. Reinforces a 6-degree glide slope to helicopter approaches.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Cramp&rsquo;s Helipad Approach Path Indicator<\/span><\/strong> &ndash; Visual aid to pilots ensuring a safe approach path. Can be installed at airports or heliports. Reinforces a 6-degree glide slope to helicopter approaches.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Clearance Bar Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Three in-pavement steady-burning yellow lights installed at holding positions on taxiways.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Clearance Bar Lights<\/span><\/strong> &ndash; Three in-pavement steady-burning yellow lights installed at holding positions on taxiways.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Controller&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Device that provides power to lighting system and prevents overloads of lamps and other products.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Controller<\/span><\/strong> &ndash; Device that provides power to lighting system and prevents overloads of <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Lamps&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Bulbs within airfield lights typically available as low, medium, or high intensity level.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>lamps<\/span> and other products.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Compliance&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Compliant products meet or exceed standards in order to be granted a specific accreditation (e.g., UL Listed, ISO 9001, FAA, ICAO).&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Compliance<\/span><\/strong> &ndash; Compliant products meet or exceed standards in order to be granted a specific accreditation (e.g., UL Listed, ISO 9001, FAA, ICAO).<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Current Driven&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Type of circuit requiring constant amperage and variable voltage.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Current Driven<\/span><\/strong> &ndash; Type of circuit requiring constant amperage and variable <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Voltage&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Difference in electric potential between two points, relevant for rating lights. Different lighting fixtures require varying amounts of voltage.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>voltage<\/span>.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Elevated Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Lighting fixtures installed with light source above ground level.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Elevated Lights<\/span><\/strong> &ndash; Lighting fixtures installed with light source above ground level.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Frangible Coupling&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Coupling designed to shear or break away cleanly on impact. This minimizes the damage to aircraft, signs, elevated lights, navigational\/approach aids, and protects mounting flanges or floor flanges after an incident.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Frangible Coupling<\/span><\/strong> &ndash; Coupling designed to shear or break away cleanly on impact. This minimizes the damage to aircraft, signs, <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Elevated Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Lighting fixtures installed with light source above ground level.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>elevated lights<\/span>, navigational\/approach aids, and protects mounting flanges or floor flanges after an incident.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;In-pavement\/Inset Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Fixtures with light source flush to the ground or recessed below ground level.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>In-Pavement\/Inset Lights<\/span><\/strong> &ndash; Fixtures with light source flush to the ground or recessed below ground level.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Lamps&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Bulbs within airfield lights typically available as low, medium, or high intensity level.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Lamps<\/span><\/strong> &ndash; Bulbs within airfield lights typically available as low, medium, or high intensity level.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Land and Hold Short Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Row of white pulsating lights across the runway to indicate hold short position on runways to facilitate land and hold short operations (LAHSO).&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Land and Hold Short Lights<\/span><\/strong> &ndash; Row of white pulsating lights across the runway to indicate hold short position on runways to facilitate land and hold short operations (LAHSO).<\/li><li><b><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Line Voltage&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;The potential difference between two phases or lines, or the voltage running through an electrical circuit. In an airfield lighting system, the term line voltage is often used to describe the power feed on the utility side of the Constant Current Regulator.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Line Voltage<\/span><\/b> &ndash;&nbsp;<span style=\"text-align: var(--text-align); font-size: 1rem;\">The potential difference between two phases or lines, or the <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Voltage&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Difference in electric potential between two points, relevant for rating lights. Different lighting fixtures require varying amounts of voltage.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>voltage<\/span> running through an electrical circuit. In an airfield lighting system, the term <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Line Voltage&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;The potential difference between two phases or lines, or the voltage running through an electrical circuit. In an airfield lighting system, the term line voltage is often used to describe the power feed on the utility side of the Constant Current Regulator.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>line voltage<\/span> is often used to describe the power feed on the utility side of the Constant Current <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Regulator&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Device controlling the proper amount of electricity being sent to airfield lights to provide precision control of runway lighting circuits.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Regulator<\/span>.<\/span><\/li><li><b><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Obstruction Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Lights installed to alert air traffic to the presence of large structures (radio towers, smokestacks, cranes, etc.) at night.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Obstruction Lights<\/span><\/b> &ndash; Lights installed to alert air traffic to the presence of large structures (radio towers, smokestacks, cranes, etc.) at night.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Precision Approach Path Indicator&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Visual aid that provides guidance information to acquire and maintain a proper glideslope to a runway when landing at an airport.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Precision Approach Path Indicator<\/span> (PAPI)<\/strong> &ndash; Visual aid that provides guidance information to acquire and maintain a proper glideslope to a runway when landing at an airport.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Qualified Electrician&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Professional with knowledge and skills related to the operation or maintenance of electrical fixtures and associated hazards. (This definition is not specific to airfield lighting).&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Qualified Electrician<\/span><\/strong> &ndash; Professional with knowledge and skills related to the operation or maintenance of electrical fixtures and associated hazards. (This definition is not specific to airfield lighting).<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Regulator&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Device controlling the proper amount of electricity being sent to airfield lights to provide precision control of runway lighting circuits.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Regulator<\/span><\/strong>&nbsp;&ndash; Device controlling the proper amount of electricity being sent to airfield lights to provide precision control of runway lighting circuits.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Runway Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Lights outlining an airport&rsquo;s runway for night and low-visibility operations.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Runway Lights<\/span><\/strong> &ndash; Lights outlining an airport&rsquo;s runway for night and low-visibility operations.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Runway Centerline Lighting System&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;System of lights embedded into the surface of the runway at intervals along the centerline of some precision instrument runways.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Runway Centerline Lighting System<\/span><\/strong> &ndash; System of lights embedded into the surface of the runway at intervals along the centerline of some precision instrument runways.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Runway End Identifier Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;A unidirectional (facing approach direction) or omnidirectional pair of synchronized flashing lights installed at the runway threshold, one on each side.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Runway End Identifier Lights<\/span> (REIL)<\/strong> &ndash; A unidirectional (facing approach direction) or omnidirectional pair of synchronized flashing lights installed at the runway threshold, one on each side.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Runway Edge Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Series of white elevated lights that run the length of the runway on either side. On precision instrument runways, the amber lighting is used in the final third or 2,000 ft of runway (whichever is less in the specific instance). These systems are generally classified by intensity as low-intensity runway lights (LIRL), medium-intensity runway lights (MIRL), or high-intensity runway lights (HIRL).&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Runway Edge Lights<\/span><\/strong> &ndash; Series of white <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Elevated Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Lighting fixtures installed with light source above ground level.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>elevated lights<\/span> that run the length of the runway on either side. On precision instrument runways, the amber lighting is used in the final third or 2,000 ft of runway (whichever is less in the specific instance). These systems are generally classified by intensity as low-intensity <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Runway Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Lights outlining an airport&rsquo;s runway for night and low-visibility operations.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>runway lights<\/span> (LIRL), medium-intensity <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Runway Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Lights outlining an airport&rsquo;s runway for night and low-visibility operations.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>runway lights<\/span> (MIRL), or high-intensity <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Runway Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Lights outlining an airport&rsquo;s runway for night and low-visibility operations.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>runway lights<\/span> (HIRL).<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Runway Guard Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Either a pair of elevated flashing yellow lights installed on either side of the taxiway, or a row of in-pavement yellow lights installed across the entire taxiway, at the runway holding position marking at taxiway\/runway intersections.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Runway Guard Lights<\/span><\/strong> &ndash; Either a pair of elevated flashing yellow lights installed on either side of the taxiway, or a row of in-pavement yellow lights installed across the entire taxiway, at the runway holding position marking at taxiway\/runway intersections.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Stop Bar Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;A row of red, unidirectional, steady-burning in-pavement lights installed across the taxiway at the runway holding position, and elevated steady-burning red lights on each side for low visibility conditions. A controlled stop bar is operated by ATC in conjunction with the taxiway centerline lead-on lights which extend from the stop bar toward the runway.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Stop Bar Lights<\/span><\/strong> &ndash; A row of red, unidirectional, steady-burning in-pavement lights installed across the taxiway at the runway holding position, and elevated steady-burning red lights on each side for low visibility conditions. A controlled stop bar is operated by ATC in conjunction with the taxiway centerline lead-on lights which extend from the stop bar toward the runway.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Taxiway Edge Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Series of blue elevated lights outlining the edge of a taxiway during periods of darkness or restricted visibility conditions.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Taxiway Edge Lights<\/span><\/strong> &ndash; Series of blue <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Elevated Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Lighting fixtures installed with light source above ground level.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>elevated lights<\/span> outlining the edge of a taxiway during periods of darkness or restricted visibility conditions.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Taxiway Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Varying lighting fixtures that may be installed in&ndash;pavement or elevated on a taxiway.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Taxiway Lights<\/span><\/strong> &ndash; Varying lighting fixtures that may be installed in&ndash;pavement or elevated on a taxiway.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Taxiway Centerline Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Steady burning inset lights located along the taxiway centerline.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Taxiway Centerline Lights<\/span><\/strong> &ndash; Steady burning inset lights located along the taxiway centerline.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Taxiway Centerline Lead-Off\/On Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Series of alternating green and yellow lights embedded into the runway pavement installed along lead-off or lead-on markings.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Taxiway Centerline Lead-Off\/On Lights<\/span><\/strong> &ndash; Series of alternating green and yellow lights embedded into the runway pavement installed along lead-off or lead-on markings.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Touchdown Zone Lights&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Row of three white light bars at intervals on either side of the centerline for the length of the Touchdown Zone.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Touchdown Zone Lights<\/span><\/strong> &ndash; Row of three white light bars at intervals on either side of the centerline for the length of the touchdown zone.<\/li><li><strong><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Voltage&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Difference in electric potential between two points, relevant for rating lights. Different lighting fixtures require varying amounts of voltage.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Voltage<\/span><\/strong> &ndash; Difference in electric potential between two points, relevant for rating lights. Different lighting fixtures require varying amounts of <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Voltage&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Difference in electric potential between two points, relevant for rating lights. Different lighting fixtures require varying amounts of voltage.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>voltage<\/span>.<\/li><li><b><span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Voltage Driven&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Constant voltage and variable amperage.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>Voltage Driven<\/span><\/b> &ndash; Constant <span class=\"glossaryLink\"  aria-describedby=\"tt\"  data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Voltage&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Difference in electric potential between two points, relevant for rating lights. Different lighting fixtures require varying amounts of voltage.&lt;\/div&gt;\"  data-mobile-support=\"0\"  data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex='0' role='link'>voltage<\/span> and variable amperage.<\/li><li><strong>Wind Cone, Lighted<\/strong> &ndash; Lighted wind cones indicate wind direction and speed. They are lighted for all-hours usability.<\/li><\/ul>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>Key Terminology <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Approach Lighting System (ALS)&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Lighting system located at the approach end of a runway consisting of a series of light bars, strobe lights, or a combination of the two, which extend outward from the runway end.&lt;\/div&gt;\" data-mobile-support=\"0\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex=\"0\" role=\"link\">Approach Lighting System (ALS)<\/span> &ndash; Lighting system located at the approach end of a runway consisting of a series of light bars, strobe lights, or a combination of the two, which extend outward from the runway end. <span class=\"glossaryLink\" aria-describedby=\"tt\" data-cmtooltip=\"&lt;div class=glossaryItemTitle&gt;Arc Blast&lt;\/div&gt;&lt;div class=glossaryItemBody&gt;Tremendous temperatures of the arc cause the explosive expansion of both the surrounding air and the metal in the arc path. Dangers associated with arc blast include high pressure, sound, and shrapnel.&lt;\/div&gt;\" data-mobile-support=\"0\" data-gt-translate-attributes='[{\"attribute\":\"data-cmtooltip\", \"format\":\"html\"}]' tabindex=\"0\" role=\"link\">Arc Blast<\/span> &ndash; Tremendous temperatures of the arc cause the explosive expansion of both the surrounding &hellip; <a href=\"https:\/\/crp.trb.org\/acrpwebresource20\/glossary\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &quot;Glossary&quot;<\/span><\/a><\/p>\n","protected":false},"author":95,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":""},"categories":[],"tags":[],"class_list":["post-2674","page","type-page","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/crp.trb.org\/acrpwebresource20\/wp-json\/wp\/v2\/pages\/2674","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/crp.trb.org\/acrpwebresource20\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/crp.trb.org\/acrpwebresource20\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/crp.trb.org\/acrpwebresource20\/wp-json\/wp\/v2\/users\/95"}],"replies":[{"embeddable":true,"href":"https:\/\/crp.trb.org\/acrpwebresource20\/wp-json\/wp\/v2\/comments?post=2674"}],"version-history":[{"count":7,"href":"https:\/\/crp.trb.org\/acrpwebresource20\/wp-json\/wp\/v2\/pages\/2674\/revisions"}],"predecessor-version":[{"id":2877,"href":"https:\/\/crp.trb.org\/acrpwebresource20\/wp-json\/wp\/v2\/pages\/2674\/revisions\/2877"}],"wp:attachment":[{"href":"https:\/\/crp.trb.org\/acrpwebresource20\/wp-json\/wp\/v2\/media?parent=2674"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/crp.trb.org\/acrpwebresource20\/wp-json\/wp\/v2\/categories?post=2674"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/crp.trb.org\/acrpwebresource20\/wp-json\/wp\/v2\/tags?post=2674"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}