LOW VISIBILITY

The Operating Environment and Aircraft Performance

Aircraft performance can be affected by a lot of things. One of the major Environmental factor is Weather and to be more specific Low visibility. Weather is a very vital factor in aviation. Poor visibility may increase the possibility of pilot errors and collision with terrain or with other aircrafts. Fog and mist are one of the main factors that affects the visibility. Fog and mist are just very low clouds that sit on the ground. Fog is defined when the visibility is lower than 5/6SM while mist is above 5/6SM. In this conditions pilots have a really hard time taking off and landing the plane, jet or helicopters. Visibility doesn’t only get lowered by the fog but also sand. This is especially very common in the Middle Eastern countries where they have a lot of Sand storms.

There are, however, ways of to proceed when you have low visibility. Different bases have their own criteria which they follow. For example in a base where I was stationed a few months back, the junior pilots could not take off if the visibility is lower than 2SM and the ceilings are lower than 300FT. It depended more on the experience of the pilot. At an airport, when the visibility drops to a certain level the airfield switches to low visibility procedures. In one article I read explained really well the low visibility procedure. “One of the main changes during the LVP’s is holding points around the runways. In good weather conditions, aircraft waiting to enter the runway hold at the CAT1 holding points. However, when landing in fog, the integrity of the signal that the runway sends up to aircraft is more vital. As a result the aircraft must wait farther back from runways, at the  CAT3 holding point.” (Page, 2019) Other procedures include Taxiing, Take off; this is when sensors are positioned at the start, middle and the end of the runway- known as the touchdown  midpoint and stop end, the sensors measure the visibility in meters and are reported to the pilots. This are just but a few of many procedures that different airports do when that are faced by the Low visibility condition.

Reference.

    Page, C (2019, November 16) The point Guy. Low Visibility: How aircrafts operate in foggy condition.https://thepointsguy.com/guide/aircraft-operating-foggy-conditions/