LED Light Sources in the Approach Slope Indicators and Their Visibility in Inhomogeneous Atmosphere

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60162694%3AG43__%2F15%3A00531577" target="_blank" >RIV/60162694:G43__/15:00531577 - isvavai.cz</a>

Výsledek na webu

<a href="http://vavtest.unob.cz/registr" target="_blank" >http://vavtest.unob.cz/registr</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1109/DASC.2015.7311394" target="_blank" >10.1109/DASC.2015.7311394</a>

Jazyk výsledku

angličtina

Název v původním jazyce

LED Light Sources in the Approach Slope Indicators and Their Visibility in Inhomogeneous Atmosphere

Popis výsledku v původním jazyce

The PAPI (Precision Approach Path Indicator)optical system with incandescent light sources (halogen airport lamps) is already an integral part of the airport lighting system (ALS), both stationary and mobile airfields of The Czech Air Force. The development unambiguously directs to the replacement of the incandescent light sources in the APAPI (Abbreviated PAPI) an optical unit with LED (Light-Emitting Diodes) light source with the high luminous efficacy. Considerable technological and light differences among the LED light sources and the halogen airport lamps lead to high difficulties of the theoretical design, development and construction of the new LED APAPI optical system assembly. This article illustrates the shape, light efficiency and spectral characteristics, differences among the LED light sources and the halogen airport lamps and a possible way of APAPI optical system design with LED light sources. Every element of the approach slope indicator system must be watched for the minimum specific time to provide information. This time is defined at least 2 or 3 seconds and most importantly depends on the pilot and his abilities. The visibility of the APAPI light is caused by its light on the retina surface in the eye. The basic requirement is the fact that the intensity of the light must be on a higher level than the contrast threshold. The contrast threshold depends on lots of conditions - basically on the color of the light or on the bandwidth of the light spectrum, brightness of the background, a current state of the pilot, etc. If the light source dimension is small enough - ten centimeters watched from hundreds meters – it is considered as a spot light. Anyway, Allard’s law is used for the range determination of the simple APAPI light. The results of these eflections are described and defined in the aerodrome standards and documents, especially in ICAO Annex 14 for a long time. However, these kinds of standards are built only for classical light sources.

Název v anglickém jazyce

LED Light Sources in the Approach Slope Indicators and Their Visibility in Inhomogeneous Atmosphere

Popis výsledku anglicky

The PAPI (Precision Approach Path Indicator)optical system with incandescent light sources (halogen airport lamps) is already an integral part of the airport lighting system (ALS), both stationary and mobile airfields of The Czech Air Force. The development unambiguously directs to the replacement of the incandescent light sources in the APAPI (Abbreviated PAPI) an optical unit with LED (Light-Emitting Diodes) light source with the high luminous efficacy. Considerable technological and light differences among the LED light sources and the halogen airport lamps lead to high difficulties of the theoretical design, development and construction of the new LED APAPI optical system assembly. This article illustrates the shape, light efficiency and spectral characteristics, differences among the LED light sources and the halogen airport lamps and a possible way of APAPI optical system design with LED light sources. Every element of the approach slope indicator system must be watched for the minimum specific time to provide information. This time is defined at least 2 or 3 seconds and most importantly depends on the pilot and his abilities. The visibility of the APAPI light is caused by its light on the retina surface in the eye. The basic requirement is the fact that the intensity of the light must be on a higher level than the contrast threshold. The contrast threshold depends on lots of conditions - basically on the color of the light or on the bandwidth of the light spectrum, brightness of the background, a current state of the pilot, etc. If the light source dimension is small enough - ten centimeters watched from hundreds meters – it is considered as a spot light. Anyway, Allard’s law is used for the range determination of the simple APAPI light. The results of these eflections are described and defined in the aerodrome standards and documents, especially in ICAO Annex 14 for a long time. However, these kinds of standards are built only for classical light sources.

Druh

D - Stať ve sborníku

CEP obor

KA - Vojenství

OECD FORD obor

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Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2015

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

34th DASC Proceedings

ISBN

978-1-4799-8939-3

ISSN

—

e-ISSN

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Počet stran výsledku

9

Strana od-do

1-9

Název nakladatele

ALR International

Místo vydání

Orlando, USA

Místo konání akce

Praha

Datum konání akce

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Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

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