3.2 Aircraft Systems and Flight

No matter how you look at it, failure of the main rotor hub retention nut on a helicopter can and will lead to catastrophe if the aircraft is already in flight. Affectionately known as the "Jesus Nut", if this one part fails, the only thing left for the flight crew to do is pray to Jesus. That's because this particular piece of securing hardware is the only thing connecting the rotor assembly (rotor blade, blade grips, control rods, etc.) to the rotor mast which provides the rotation. With no main rotor the aircraft will literally drop out of the sky.

       

Some current generation helicopters do not have this type of hardware, but most still do. As aerospace engineers progress into different design characteristics, there may be better ways to secure this critical piece to the airframe. For now, ensuring the nut is free from corrosion and always properly torqued is the best way to prevent failure.


References:

Image #1 - Retrieved from https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEg8Gv4g2uwPulYPAR-z4B9aFbE5r_RhmO9UGo3VLqA38fDv-EWhDRiVebaEceY6hm_fDUaiAydjKi_mVchYPk-AZxrcvmnksU2Buf6YganV3IbT5HpBrG_KiwGmVwDsCTZ7nQDK7wtxrDg/s320/jesus_nut_helicopter.gif

Image #2 - Retrieved from https://image.jimcdn.com/app/cms/image/transf/dimension=456x10000:format=jpg/path/sdccddb58c2347489/image/i353855190ae8611f/version/1546877353/jesus-nut-helicopter.jpg

Image #3 - Retrieved from https://www.ocregister.com/wp-content/uploads/migration/kpj/kpjj8j-b78395062z.120080901211719000gi3dstpr.1.jpg?w=620

2.3 The Operating Environment and Aircraft Performance

I'm actually surprised that I may be the first to mention bird and/or wildlife strikes for this assignment.  Since humans now share the skies with birds, mid-air collisions are inevitable.  One of the most famous examples would be US Airways Flight 1549 in 2009, where Captain "Sully" Sullenberger successfully performed a controlled water landing on the Hudson River in New York City.  His aircraft suffered catastrophic dual engine failure after striking a flock of geese.

Even though bird strikes are the most recognizable, wildlife strikes by aircraft on the ground during taxiing, takeoff, or landing can be just as crippling.  According to the Aircraft Owners and Pilots Association website (2019), "Bird and wildlife strikes can be serious and have resulted in more than 350 fatalities. The aviation industry spends nearly $330 million and suffers 500,000 hours of down time each year from strikes." (Statistics section, para. 1)

The FAA website (2019) states they are "undertaking an aggressive research program to mitigate wildlife strikes with aircraft by providing practical solutions as well as timely, critical information to pilots and airport managers." (Research and Development section, para 2.)  These solutions focus on Habitat Management, Detection Methods, Wildlife Control Techniques, Systems Integration, and working with Research & Development Partners (one of which is ERAU-Prescott, Center for Wildlife and Aviation!)


References:
Retrieved from https://static01.nyt.com/images/2010/05/05/nyregion/05ntsb_CA0/05ntsb_CA0-popup.jpg

Retrieved from https://www.aopa.org/training-and-safety/active-pilots/safety-and-technique/bird-and-wildlife-strikes

Retrieved from http://heartalaska.com/wp-content/uploads/2015/02/Eielson-AFB-Moose-1625.jpg

Retrieved from https://www.faa.gov/airports/airport_safety/wildlife/rd/

1.4 Ethics in Aviation

Our first core value in the USAF is Integrity First...Integrity is a character trait. It is the willingness to do what is right even when no one is looking. It is the “moral compass”—the inner voice; the voice of self– control; the basis for the trust that is essential in today’s military. (United States Air Force Core Values, 1997)  This is paramount, for what should be an obvious reason...trustworthiness.  It's drilled into Airmen from Day 0 at Basic Training.  If you can't be trusted to meet basic military standards such as shaving, keeping your hair trim, or staying fit, how can you be trusted to torque those bolts on the aircraft?  While on the surface that seems like an extreme conclusion, it drives home the point that integrity really can be the difference between life and death.  Take a shortcut and people could die.  In the aviation industry, it's no different.  On the low end of the risk matrix, an aircraft or a piece of support equipment stays broken or costs more than it should to repair.  At the high end of the risk matrix is loss of life.  Those that become involved in the field of aviation should always be aware of these risks and strive to mitigate them as much as possible, starting with integrity.

U.S. Air Force. (2012). Air Force Culture (AFI 1-1, pg 4). Retrieved from https://static.e-publishing.af.mil/production/1/af_cc/publication/afi1-1/afi1-1.pdf