787 cockpit showing TCAS on the Multi-Function Display – Photo: AirlineReporter
A few months ago, a near-collision between two Boeing 757s off the coast of Hawaii was in the headlines. This event was particularly noteworthy because of the emergency descent made by United Airlines Flight 1205, which descended over 600 feet in a matter of seconds, terrifying passengers and sending items flying in the cabin. The pilots on the United flight were alerted to the oncoming traffic, and took action based on their Traffic Collision Avoidance System (TCAS).
History of mid-air incidents and TCAS mandate
Although TCAS systems are a (relatively) recent development in airline cockpits, the need for such systems was recognized long ago. On June 30,1956, a mid-air collision occurred at 20,000 feet between a United Airlines DC-7 and a TWA Lockheed 1049 over the Grand Canyon in northern Arizona. This incident, which resulted in 128 fatalities, served as a wake-up call for the aviation industry. Prior to the collision, “big sky theory” was the prevailing notion – that two aircraft flying in three-dimensional space were very unlikely to collide. Following this incident (which also led to the creation of the FAA), research began on developing collision avoidance systems.
N670H was the first aircraft in the world to be certified with TCAS. Photo by Bernie Leighton | AirlineReporter.com
Recently I spent a day with Honeywell Aerospace and it had clearly worked its way into my brain at a deeper-than-expected level.
Before I found the opportunity to go over my notes and write a follow-up article about my time with the Honeywell Crash Test Dummies up at Paine Field, I found myself on board an American Airlines Boeing 737. My first thought, after it was clear that tower had given us a “taxi into position and hold” command for Runway 34R at SEA was, “I sure hope this aircraft has RAAS.”
Runway Awareness and Advisory System is a Honeywell Aerospace product that allows pilots to enhance their situational awareness by providing audible and visual cues about the aircraft’s location relative to its destined runway. Once the aircraft arrives on the runway, it is capable of reminding flight crew that they are still on the runway after one minute and thirty seconds. This time was decided on by Honeywell’s research team. After ninety seconds on the runway, research shows that the safe course of action is to make a radio call to the tower reminding them of your position and intent. That technology alone saves lives and prevents damage, but if you think Honeywell stopped there, you would be wrong.