Earth's environment can change drastically and challenge pilots as the fly across the globe. Pilots must be focused and ready to take-on any situation the comes their way. Sometimes there are situations that occur that can catch the pilot off guard. For example, wind shear can cause fatal damage to a pilot, their crew, and passengers if the pilot is not prepared. Wind shear can occur in the upper and lower levels of the atmosphere, but I will only be discussing the lower level atmospheric wind shear.

According to the Federal Aviation Administration (FAA) (2011), wind shear is defined as, "a rapid change in wind speed and direction over a short distance." In the lower portion of the atmosphere, wind shear can be caused by thunderstorms, temperature change, and obstruction. During thunderstorms, warm air rises on the outside of the storm and converge at the top of the storm. The warm air will then go to the center of the storm and rush to the surface at high speeds. Wind speeds can reach speeds of 100 knots per hour and can change direction up to 180 degrees. (FAA, 2011)

Temperature inversion wind shears usually occur in the southwestern region of the United States. (FAA, 2011)  During the night, the air is cooled at the surface up to a few hundred feet lower than the mountain range peaks. This cooling of air creates a temperature separation between the surface and the lower-level atmosphere. Once the warm air jet stream flows across the top of the calmer, cooler air, it creates wind shears that can change speed by 20-30 knots per hour and direction up to 90 degrees. (FAA, 2011)

Surface obstruction can also cause mini wind shears. The main obstruction that I am referring to are mountain ranges or larger buildings close to the runways. When a strong winds goes up and over mountain ranges or winding through buildings on the airports, there can be localized wind shears. Wind shears are to be expected by pilots when there are strong surface winds, the severity of the wind shear is completely unpredictable. (FAA, 2011)

Resources

FAA. (2011, August). Wind Shear. Retrieved from FAA Safety: https://www.faasafety.gov/files/gslac/library/documents/2011/Aug/56407/FAA%20P-8740-40%20WindShear%5Bhi-res%5D%20branded.pdf

Module 8: Air Traffic Control Entities

During this post, I will be discussing two Air Traffic Control entities that must be able to diligently work with one another in order to have successful operations. The first entity that I will be discussing is the Airport Traffic Control Tower's (ATCT) duties and responsibilities. Next I will discuss the duties and responsibilities of the Terminal Radar Approach Control (TRACON).

ATCT can be made up of anywhere between three and ten positions within it depending on how busy the airport is. Two of the positions that I would like to talk about are the ground controller and local controller. Ground controllers are ultimately responsible for ensuring the separation of  aircraft while being taxied from landing, aircraft being taxied prior to taking off, and managing ground vehicles in airport moving areas. (Nolan, n.d.)  The local controller is responsible for determining active runways, separation of aircraft in the local area and active runways, and issuing landing and takeoff clearances. (Nolan, n.d.)  These two positions have a significant impact on airport operations. If these positions, along with other positions are not careful, fatal accidents could occur.

TRACON, typically found at larger airports, hosts up to 40 approach and departure controllers. (Nolan, n.d.)  These controllers are surrounded by up to 20 monitors that displays incoming and out going aircrafts. While at larger airports, the approach and departure controllers are assigned airspaces to maintain since the job may be too big for one individual. (Nolan, n.d.)  TRACONs will ensure that departing aircraft air correctly deconflicted and then hand the responsibility of the aircraft to another TRACON to ensure continuous tracking is done on the airframe.

Module 7: The Airport and the Environment

Airports have many concerns when operating in their respective environments. For example, wildlife, pollution, terrain, and population are all concerns for airports when making operational decisions. During this post, I will be discussing noise issues and concerns for the airports neighboring populations. I will also discuss methods that are currently used and methods that are suggested for the future to reduce and/or eliminate the noise of airplanes.

There are a combination of noises that are made from different parts of an airframe. These parts include propellers, engines, flaps, landing gears, and operations that occur around the airport. Studies have been conducted by many doctors that show aircraft related noise has been proven to cause learning disabilities and hypertension. (Kaltenbach, Maschke, & Klinke, 2008)  In 2001, it was found that more than 2,900 adults had hypertension related symptoms when around continuous aircraft related noises between 55 and 72 decibels (dB).  (Kaltenbach, Maschke, & Klinke, 2008)  Furthermore, more than 2,000 men between the ages 40 and 60 were evaluated for a 10 year period. These evaluations concluded that there was a 20% increase to the risk of hypertension with continuous noises of 50 dB's.  (Kaltenbach, Maschke, & Klinke, 2008). Additionally, studies were conducted on over 2,800 children from ages 9 to 13 in 89 different schools. it was determined that an increase to aircraft related noises deteriorated silent reading comprehension and memory performance.  (Kaltenbach, Maschke, & Klinke, 2008)

While completely eliminating airport noises is impossible at the moment, the Federal Aviation Administration (FAA) currently has rules in place to reduce the noise levels of specific aircraft types. Currently there are four stages of noise levels created by the FAA. Stage 1 (Loudest), Stage 2, Stage 3, and Stage 4 (Quietest). The noise levels are identified in Code of Federal Regulation Title 14, Chapter 1, Subchapter C, Part 36. Prior to January 1, 2016, civil jet aircrafts that meet a weight less than 75,000lbs is required to meet the noise requirements of Stage 3 or stage 4; Aircrafts 75,000 or more will have to meet Stage 2, Stage 3, or Stage 4 requirements. (FAA, 2019) As of January 1st, 2016, regardless of the civil jet aircrafts weight, it must meet Stage 3 or Stage 4 noise level requirements. (FAA, 2019)  Furthermore, Helicopters are allowed to operate at Stage 1 and Stage 2 noise level requirements.

References

FAA. (2019, Janurary 9). Aircraft Noise Issues. Retrieved from Federal Aviation Administration (FAA): https://www.faa.gov/about/office_org/headquarters_offices/apl/noise_emissions/airport_aircraft_noise_issues/

Kaltenbach, M., Maschke, C., & Klinke, R. (2008, August). Health Consequences of Aircraft Noise. Retrieved from National Center for Biotechnology Information: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2696954/



Module 6: Legislative Acts

Laws and regulations are what helps ensure successful operations and safety in aviation. Laws and regulations are what the Federal Aviation Administration (FAA) use to hold people and airlines accountable. Rather than focusing on rules that hold pilots or air crews accountable for their actions, I would like to look into an aircraft structure regulation that promotes structure durability. More specifically, I will be discussing the Code of Federal Regulations (CFR) 14 §25.365 “Pressurized Compartment Loads”. This regulation defines the safety precautions to be implemented in the instance that a pressurized compartment is penetrated during mid-flight operations. 

FAA CFR 14 §25.365 is a regulation comprised of 6 sections that takes into consideration the safety of the passengers on board the aircraft. Section (g) of the CFR 14 §25.365 (2019) states, "Bulkheads, floors, and partitions in pressurized compartments for occupants must be designed to withstand the conditions specified in paragraph (e) of this section."  The FAA wants to ensure that if the frame of the aircraft is to be penetrated, then chairs and luggage compartments will not be pulled through the hole of the aircraft during the rapid depressurization process. This helps to increase the safety of all the passengers on board the air frame. 

An example of this situation occurring is on the Daallo Airlines Flight 159 on February 2nd, 2016. at that time, it was suspected that members of the Al-Shabaab terrorist group were the cause of the explosion. (Kriel, 2016)  These people brought an explosive devices disguised as a laptop on to the plane that exploded and penetrated the frame of the aircraft. The cabin immediately depressurized and unfortunately pull one passenger through the hole of the aircraft. However, due to the cabins durability, the aircraft remained in contact through the entirety of the event and landed safely.

Resources

Federal Aviation Administration. (2019, May 30). Title 14: Aeronautics and Space, Part 25: Airworthiness Standards: Transport Category Airplanes. Retrieved from Electronic Code of Federal Regulations: https://gov.ecfr.io/cgi-bin/text-idx?SID=77d90aa989f16f6c71fd99e5015dacba&mc=true&node=se14.1.25_1365&rgn=div8

Kriel, R. (2016, February 12). Source: 'Sophisticated' laptop bomb on Somali plane got through X-ray machine. Retrieved from CNN: https://www.cnn.com/2016/02/11/africa/somalia-plane-bomb/index.html

Module 5: Team-Based Human Factors Challenges

Human Factors in aviation involve the humans physical and mental ability to perform when operating aviation equipment. Some common factors that are taken into consideration is communication, fatigue, knowledge, mental state, physical limitations, and many more. (Weiner & Nagel, 1988) Furthermore, human factors can vary depending on the person. The way one individual may retain information or react in a certain situation is not the way another person will react in a similar situation.

I would like to focus on a personal team based event that I was involved in from the years 2013-2016. I work at the 81st Range Control Squadron (RCS) at Tyndall AFB, Fl.  At the 81st RCS, we conducted hundreds of Weapon System Evaluation Program (WSEP) exercises every year that dealt with the live firing of air-to-air missiles. There were five positions that were involved in this exercise: The Interface Control Technician (ICT), Live Technician (LT), Drone Coordinator (DC), Weapons Director (WD), and Mission Director (MD). Each position was responsible for its specific portion of the mission and required flawless coordination between the crew and participants (i.e. Pilots and Air Traffic Control (ATC)).

The human factors that I would like to focus on is fatigue, communication, and experience. During WSEPs, there are times when exercises were conducted as early as 0400 and last four to five hours in duration. Depending on personal situations, sometimes crew members would be tired and lack the attention to detail needed for the duration of the exercise. Furthermore, there would be situations where we would train new Airmen on the crew positions during the live fire events. These new members would like the experience and knowledge of some of the senior members in the squadron. These new Airman would some times not communicate necessary calls to the WDs or not pass information to the pilots or ATC causing there to be confusion.

(Actual image from the 81 RCS Operations Floor)

Rather than mechanical malfunctions, human factors can be the root cause of many of the aviation incidents that occur. According to Wiegmann and Shappell (2001), human error is responsible for 70-80% of all civil and military aviation incidents. in saying that, companies and airlines have looked into ways at reducing the negative effects of human factors rather than focusing on the mechanical issues. The only issue with reducing human factor errors is, the post analysis reports not taking into account the human error.

References

Wiegmann, D. A., & Shappell, S. A. (2001). A Human Error Analysis of Commercial Aviation Accidents Using the Human Factors Analysis and Classification System (HFACS). Springfeild: National Technical Information Service.

Wiener, E. L., & Nagel, D. C. (1988). Human Factors in Aviation (2nd ed.). (E. Salas, & D. Maurino, Eds.) Gulf Professional Publishing. Retrieved from https://books.google.de/books?hl=en&lr=&id=Fi2Bqh_6fW4C&oi=fnd&pg=PT1&dq=human+factors+in+aviation&ots=wMPh4MtuuB&sig=bmiNSHOtqq_iylEIv7_Gs8GjaNE#v=onepage&q=human%20factors%20in%20aviation&f=false

Module 4: Aviation Security: Explosive Devices

Aviation Security: Explosive Devices

Explosive devices and threats always pose a threat to the aviation world. An explosive device, by definition, is a device that bursts with an abrupt violence from an internal combustion. Most devices are homemade by someone with ill intent and the goal of hurting people or a political aim.

There are security procedures put in place to prevent explosive devices from entering an airport, along with many other measures. The most common are x-ray machines metal detectors. Since human profiling will never be 100% accurate, these machines are designed to help the operators identify what they are not able to see with the naked eye. (Merari, 2007)  Along with machines, there are procedures that must be followed to help ensure safety. From personal experience, my flight was delayed due to a bag being left on board from the previous flight. Due to a random bag being left on the plane, security assumed for the worst scenario and presumed it was an explosive device. Hours later, it was just an accident from one of the passengers from the previous flight.

The most common issue with the security measures put in place is the experience of the operators the perform the security checks with the equipment that they are given. (Michel, et al., 2007)  Many of them lack the proper experience needed to make the detection devices perform at their maximum capabilities. My recommendation would be that TSA take the time and funds necessary to properly train their employees. This would maximize efficiency when operating security equipment.

- Marquise Cunningham

References

Merari, A. (2007). Attacks on civil aviation: Trends and lessons. Terrorism and Political Violence, 9-26. Retrieved from https://www.tandfonline.com/doi/pdf/10.1080/09546559808427466?casa_token=2Gu8WM-a_scAAAAA%3AFJEaYA4y5AJAXHvDvRdaTuOAjKoiHgnPaW0HWaDcqWjl50PsI7COiixCfOhtj6nUzE4AjW_yBZmIe3U&

Michel, S., Koller, S. M., de Ruiter, J. C., Moerland, R., Hogervorst, M., & Schwaninger, A. (2007). Computer-Based Training Increases Efficiency in X-Ray Image Interpretation by Aviation Security Screeners. Ottawa: IEEE.

Module 3: Aircraft Systems and Flight:

In the aviation world, there are an abundance of weather scenarios the pilot could encounter during takeoff, mid-flight operations, and landing that can put the pilot and their passengers in danger. Icing is a condition that can manipulate the performance of the aircraft. After years and centuries of first hand experiences and observations, science and meteorology brought to light the dangers of icing in aviation.




Icing is when ice forms on the frame of a boat, vehicle, engine, or an aircraft. Icing occurs when an aircraft flies through a cloud that has supercooled droplets of water vapor. In order for a cloud to contained supercooled droplets, the cloud must have a temperature range of 0 degrees Celsius and -25 degrees Celsius. (Politovich, n.d.)  Furthermore, there are three types of icing: Rime icing, Glaze icing (clear icing), and Mixed icing. Rime icing is brittle ice that forms and grows into the airstream, Glaze icing is a clear, transparent, smooth surface of ice that forms along the surface of the aircraft, and Mixed icing is a combination of Rime and Glazed icing. (Politovich, n.d.)

Rime Icing

Glazed (Clear) Icing

Mixed Icing

When icing occurs on an aircraft, hazards occur that effect the control of the airplane. When ice forms, it can reduce air speeds, negatively effect airflow, and reduce lift by up to 30% and/or increase drag by up to 40%. (Arbogast, 2013)  Essentially, having ice on an aircraft can cause it to crash

To prevent icing from occurring on the wings of the aircraft, planes have been installed with de-icing and anti-icing systems. Propeller driven aircraft mostly use pneumatic de-icing boots. Pneumatic de-icing boots are a thermal anti-icing systems that de-ice the wing and propeller leading edges and the engine intake. Other forms of de-icing include Sonic Pulse Electro-Expulsive Deicer (SPEED), the Electro-Impulse Method, Electro-Expulsive Separation System (EESS), Electro-mechanical Expulsion Deicing System (EMEDS), Electrical Heating, Ultrasound Technology (UT), and a few more. SPEED uses Electro-Impulsive De-Icing (EIDI) that are strategically placed behind the leading edge of the wing. (Goraj, 2004)  Once ice reaches a certain thickness, the EIDI will send a pulse that will break the ice and free the wing of any obstruction. (Goraj, 2004)  Electro-Impulse method uses high-voltage capacitors to rapidly discharge through coils to, basically, throw ice off of the leading edge. (Goraj, 2004)  EESS consists of two components, the EESS Controller and the EESS Expulsive Boot and push a current through the conductors that will push them apart. (Goraj, 2004)  The force of the current will be able to break ice that is up to an inch thick. (Goraj, 2004)  EMEDS uses an electrical pulse to send repetitive pulses to rapidly change the shape of the actuators in order to remove the ice on the wing. (Goraj, 2004)  Electrical heating basically says what it does in its name. The electrical heating method uses a graphite based heating method to rapidly heat its section and dis-bond it from the frame, allowing the airflow to remove the ice without melting it. (Goraj, 2004)  Finally, UT uses sound waves to cause stress between two martials in order to separate them. (Goraj, 2004) 

SPEED

EESS

EMEDS

UT

References



Arbogast, S. (2013, July 30). Aircraft Icing and How it Affects Your Flight. Retrieved from Universal Weather & Aviation, Inc.: http://www.universalweather.com/blog/aircraft-icing-and-how-it-affects-your-flight/

Baars, W. J., Stearman, R. O., & Tinney, C. E. (2010). A Review on the Impact of Icing on Aircraft Stability and Control. ASD Journal, 35-52.

Goraj, Z. (2004). An Overview of the Deicing and Antiicing Technologoes with Prodpects for the Future. International Congres of the Aeronautical Sciences (pp. 1-11). Warsaw: Warsaw University of Technology.

Politovich, M. K. (n.d.). Aircraft Icing. In G. R. North, J. A. Pyle, & F. Zhang, Encyclopedia of Atmospheric Sciences (Vol. 1, pp. 160-166). Retrieved from https://books.google.it/books?hl=en&lr=&id=8lpzAwAAQBAJ&oi=fnd&pg=PA160&dq=rime+icing+aviation&ots=ZGOPcliEZz&sig=0GNeigmkeWdrQcMqjuLEqLhKWYk#v=onepage&q&f=false

 

- Marquise Cunningham