9-2 Weather Hazards

 

The weather hazard that poses the greatest risk to aviation operations in my opinion is the occurrence of a microburst. In my opinion this is one of the deadliest and hardest challenges to overcome. I chose this hazard because in many different rounds of simulator training I have participated in, a severe microburst is the hardest condition to land in. A microburst can occur suddenly and needs to be reacted to immediately to safely avoid this phenomenon.

A microburst is a severe type of low-level wind shear associated with convective precipitation (FAA, 2016). Wind shear is a when a sudden drastic change in wind speed and or direction in a very small area (FAA, 2016). For a microburst to occur several parameters are required: instability, high precipitable weather, dry air in the mid-levels, and strong winds in the dry layer (National Weather Service, n.d.). Microbursts can be life threatening, especially to aviation operations; recorded events in the past have shown wind speeds reaching up to 100mph with severe wind shift and precipitation

Below is an example of what could occur if an aircraft encountered a microburst while on approach. With a shocking headwind at first increasing the lift of an aircraft, the downdrafts then appear forcing planes down, and finally a severe tailwind may appear reducing the lift capabilities of an aircraft that may be close to the ground and needing every bit of lift possible.

The F.A.A. has posted an advisory circular on how to recognize microburst events and how to safely recover if encountered in several different regimes. In my opinion the most dangerous time for this occur is when an aircraft is low to the ground and slow, often found at takeoff and landing phases. According to the A.C. 00-54 the recovery technique for both phases of flight is the same (FAA, 1988). First aggressively apply necessary thrust, apply a normal pitch rate to a target of 15 degrees, and maintain current flap and gear configuration until clear of obstacles. Of course, every situation is different, and techniques may vary, but essentially the F.A.A. proposes to maintain airspeed, begin a climb and get of dodge as quickly as possible.

Finally, below is a video illustrating the hazard of a microburst event and why it should be given the utmost respect and avoided like a plague.

 

References

F.A.A. (1988). Advisory circular 00–54 pilot wind shear guide. Faa.Gov. https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC00-54.pdfF.A.A. (2016).

Microburst winds [Photo]. https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/media/14_phak_ch12.pdfNational Weather Service. (n.d.).

What is a microburst? Weather.Gov. https://www.weather.gov/bmx/outreach_microburstsThis Is

Why You Don’t Want to Fly into a Microburst. (2014, April 8). [Video]. YouTube. https://www.youtube.com/watch?v=HDfodeURad0

What is a microburst. (n.d.). [Photo]. https://www.quora.com/What-is-a-microburst-and-why-is-it-very-dangerous-for-aircraft