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Questions tagged [visibility]

The maximum distance at which objects can be seen.

6
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2answers
2k views

Why is autolanding ILS a thing, but not autotakeoffing ITS? [duplicate]

In this answer to the question of why zero-visibility landings are legal and routine but not zero-visibility takeoffs, the poster makes the following point: When an aircraft lands in near zero ...
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0answers
49 views

Does the use of a turboclair system come with operational restrictions due to possible turbulence?

A turboclair system basically consisted of jet engines used to warm the air around the runway and dissipate the fog. I understand that better visibility due to less fog allows less-well-equipped ...
1
vote
1answer
268 views

Why can't pilots manually fly a low visibility approach instead of using auto land?

Pilots have instruments that help them land. But in low visibility they are required to use auto land. Why can't they rely on their instruments at those times?
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0answers
39 views

From how far away are the navigation lights of a large airliner typically visible? [duplicate]

I live about 22 miles away from one international airport in the UK, and just over 30 miles away from another. When I spot aircraft lights at night and check for corresponding aircraft on ...
3
votes
3answers
287 views

Why is there no instrument taxi system for low-visibility operations?

In one of the comments on this answer regarding ILS category IIIc operations (or, rather, the lack thereof), it's mentioned that There is no [radio] guidance for taxiing except the pilot's vision. ...
5
votes
1answer
124 views

How good is the ground visibility by a moonless night In the Grand Canyon?

My night flying experience is limited to light-polluted coastal southern California. When flying over low-population countryside on a clear, moonless night, do the stars provide enough light to ...
3
votes
1answer
390 views

What is acceptable visual cue at Decision Height when performing CAT II approach?

For CAT II approach, the decision height is below 200ft but not lower than 100ft with RVR of 300m. In this case, if the aircraft is at 100ft above the ground, should the captain of that aircraft be ...
14
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7answers
2k views

Why can a plane land in zero visibility conditions but not take off in zero visibility?

After waiting hours for a flight departure delayed because of heavy fog, I wonder why planes can perform an instrument landing with no visibility, but cannot take off without a minimum visibility.
5
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1answer
317 views

What does METAR show when actual RVR is below the reporting minimum?

RVR is measured between 50m and 1500m (ICAO). When the actual RVR is below 50m, what does METAR show?
4
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1answer
332 views

Can the touchdown RVR be replaced by the midpoint or rollout RVR?

When there are three RVRs equipments in place and an ILS approach chart minumum for the runway simply says "RVR 800m" without any additional notes, is the touchdown RVR the only controlling RVR? If so,...
3
votes
3answers
232 views

What constitutes “the lights delineating the runway”?

ICAO defines RVR as "The range over which the pilot of an aircraft on the centerline of a runway can see the runway surface markings or the lights delineating the runway or identifying its centerline."...
5
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1answer
320 views

Does the definition of visibility take object size into account?

Overall, visibility is the distance at which objects may be discerned. Does this definition take into account the size of the objects? Obviously large objects can be seen from farther away than small ...
5
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1answer
3k views

What is the relationship between temperature, dew point and the formation of clouds?

What can you infer from the temperature / dew point values in this METAR? EGJG 121630Z 09012KT 9999 SCT006 15/14 Q1015 I understand the temperature is 15 degrees and the dew point is 14, and I ...
7
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1answer
700 views

Do any aircraft windshields have anti-reflective coatings?

Anti-reflective coatings are used in many applications to reduce glare and prevent double images. Double images in particular are a concern because of the several layers involved in a cockpit window. ...
3
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5answers
1k views

Why don't aircraft (commercial and military) use reflective visor windshields?

Just like those used on an astronaut's helmet, these reflective visors can help in better visibility when facing the sun (or any bright light source). But the windshields of most aircraft (commercial ...
3
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0answers
4k views

Can I spot the drones watching me in the sky with naked eyes? [closed]

To quote John Oliver: "Yemen, home to 26 million Yemeni people, and 27 million American drones." While these numbers may be slightly exaggerated I started to ...
2
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1answer
273 views

Is white/brown-out effect hazardous during the landing roll out?

Landing on unpaved runways or runways covered by snow or dust causes a white/brown-out visibility restriction. Does it disrupt the pilot's visibility during the roll out in a fixed-wing aircraft?
9
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1answer
417 views

What is an Enhanced Vision System?

I was reading something at work that said the company has installed an Enhanced Vision System on the aircraft. FedEx Express added Enhanced Vision Systems to 250 aircraft, which will greatly ...
18
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2answers
7k views

How is the visibility at airports measured?

What tools are being used by airports to measure visibility precisely? Do we have some kind of tools on aircraft as well for measuring visibility?
3
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3answers
992 views

Is there a database of airport ceilometer raw data?

I am interested in obtaining raw ceilometer data, to test some cloud/aerosol layer identification algorithms. Is this type of data freely available or will I need to ask for it directly from the ...
6
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2answers
7k views

Which airports have ILS Cat IIIC?

Are there any airports with ILS working CATIIIC? What do the charts for this procedure look like? Is there a missed approach procedure?
14
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3answers
4k views

Why are aircraft external lights round, not tear-drop shaped?

I saw this image of a Cessna 172's tail posted on another question and it made me wonder why the beacon light is basically a cylinder, and not a more aerodynamic, teardrop shape? Image source
9
votes
1answer
860 views

Are zero visibility landings practical and desirable for commercial aviation?

With ILS cat IIIc autoland, equipped aircrafts may land on runways without visibility. However they will not be able to safely leave the runway and taxi to the gate. Airports usually close in fog ...
23
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8answers
35k views

How do pilots see at night if airplanes don't have front lights?

How can pilots identify threats ahead of them if they don't have front lights like cars?
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2answers
5k views

How can landing in zero visibility be safe?

I recognise that autoland and ILS can enable landings in zero visibility, which I presuppose in this question (e.g. in this video where touchdown happens around 5:22). Further, suppose that the fog is ...
31
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5answers
9k views

What happened during this foggy landing?

Several years ago, I was flying from the USA to Buenos Aires. That's a very long flight, and it was overnight for us. When I woke up it was early in the morning and we were over Argentina. I don't ...
1
vote
1answer
2k views

Are red obstacle lights near an airport required to be lit during the day?

What are the FAA Beacon Light Requirements for 80 foot tall High Mast Poles Near an Airport? Specifically, do the RED beacon lights need to be illuminated 24 hours per day? Or, do they only need to ...
7
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2answers
6k views

What is the definition of visibility as seen in aviation weather reports?

If you look at the National Oceanic and Atmospheric Administration's (NOAA) National Weather Service (NWS) page for Washington D.C., Reagan National Airport (KDCA), it shows hourly weather ...