Weather Hazards - Aviation Icing

When pilots talk about weather, thunderstorms are usually one of the greatest risks mentioned, and for good reason. Between turbulence, hail, microbursts, and tornadoes, thunderstorms are full of hazards. However, one often overlooked hazard which has contributed to more accidents in recent memory is the threat of aircraft icing. Icing can be difficult to predict, and in severe instances can form without warning and overwhelm an aircraft's anti-ice capability. A quick glance through AOPA's Air Safety Institute shows a handful of excellent videos discussing icing accidents involving a de-ice equipped Cirrus, a "Flight Into Known Icing" equipped TBM700, and many others.
Icing can occur anywhere... we picked up ice on this descent into Iraq!
Aircraft icing is formed when an aircraft flies through water droplets at below freezing ambient temperatures. On contact with the aircraft, these supercooled droplets turn to ice, disrupting airflow over the wings, forming over unheated windshields, and potentially creating hazardous projectiles for engines and propellers. The most hazardous icing occurs in areas of heavy moisture and temperatures right around freezing, in which heavy rainfall turns to ice on contact.The FAA's Instrument Flying Handbook (2017) recommends the following when icing is encountered, NO MATTER WHAT you are flying: 

  • Move to an altitude with significantly colder temperatures. 
  • Move to an altitude with temperatures above freezing. 
  • Fly to an area clear of visible moisture. 
  • Change the heading, and fly to an area of known non-icing conditions.
Two famous accidents in the past 15 years reflect the serious nature of Icing. Colgan 3407 was in icing conditions when it slowed well below recommended speeds and stalled in Buffalo, New York, rewriting the requirements for future Airline Transport Pilots in the process. Air France 447 encountered icing crossing the Atlantic, receiving inaccurate airspeed indications as the pitot tubes froze over. Neither aircraft was in "severe" icing conditions, but both still became contributing causes. 

I've attached a few videos that are excellent references for icing conditions and the dangers lurking within them. 

References

Airboyd (2009, May 15th) NASA Tailplane Icing Video Glenn Research Center. Retrieved from: https://www.youtube.com/watch?v=_ifKduc1hE8

AOPA Air Safety Institute (2013, November 14th) Accident Case Study: Delayed Reaction. Retrieved from: https://www.youtube.com/watch?v=0JkLR_xgayM

AOPA Air Safety Institute ( 2016, June 10th) Accident Case Study: Airframe Icing. Retrieved from: https://www.youtube.com/watch?v=aRSqLHw_6po

FAA Flight Standards (2017) Instrument Procedures Handbook. Retrieved from: https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/instrument_procedures_handbook/

Comments

Post a Comment

Popular posts from this blog

Be An Educated Flier

Image
Photo courtesy of the NTSB In 2018 a Falcon 50 super mid-size jet ran off the end of the runway at Greenville Downtown Airport, South Carolina. Both pilots were unfortunately killed, and the two charter passengers were seriously injured. As the National Transportation Safety Board investigated the charter company and pilot records, they discovered serious discrepancies in the operation of the aircraft. The acting Pilot in Command was only rated to act as a copilot in the Falcon 50, and the copilot was not rated at all to be operating a jet aircraft on any flight, let alone an instrument flight rules for-hire flight. Additionally, the aircraft was found to have a multitude of maintenance issues after a prolonged stay in storage. According to the charter company's Director of Maintenance, the repairs and renovations to restore the aircraft to service were only about 60% complete. So an aircraft was provided for the trip which was not airworthy, and flown by an aircrew which...
Read more

Overseas ATC

Image
The Differences between US and Overseas Air Traffic Control Combat King Air after an 8 hour flight from the Aleutian Islands to Misawa AB, Japan In this week's blog I'll discuss some of the differences pilots can encounter between domestic United States flying and trips to other parts of the world, specifically based on my experience flying across the Pacific, in Mexico, Quebec, and the Middle East. While English is the international language of air traffic control, for many controllers outside the US it's a second language and likely to not be the only language heard. In Montreal for instance, it's common to hear a controller rapidly switching between French to one airplane and English to the next. I'll dive a bit deeper into what makes international flying a unique and interesting challenge.  Puebla's Air Traffic Control Tower In the United States we're very spoiled with GPS approaches and nearly constant radar coverage. Gone are the day...
Read more

Aircraft Ownership (?)

Image
 I've had a lot of downtime during my current overseas deployment with the Army Reserve, and between house hunting, working on my degree, updating airline applications, and occasionally working, I've done a fair amount of research into aircraft ownership. I imagine a fair amount of CPA members can relate to the dream of aircraft ownership, as no matter how good your experience may be renting through the numerous schools in the area, it just isn't the same as being able to hop into your own airplane and fly any time you want. It certainly doesn't help that my girlfriend recently sold her beautiful Cessna 150 to upgrade to an even more appealing GlaStar. In my nearly-unlimited free time (Thanks Covid), I've done a lot of research that has led me all over the map and probably will continue to do so as I wind my way down the rabbit hole until a beautiful, new-to-me airplane is parked in my hangar.  In the past I've done part-time work as an aircraft broker, and my f...
Read more