What’s mysterious about the recent tragic collision between a US Army Sikorsky UH-60 Black Hawk helicopter and the American Eagle Flight 5342, was the failure of the normal procedure of “see and avoid” and the lack of an avoiding manoeuvre from the helicopter[1].
Taking the timings from reports of the investigators’ work so far, the air traffic controller’s instruction to the military helicopter to pass behind the commercial jet was seventeen seconds before the catastrophic collision impact. Given the trajectory of the commercial jet, as the pilots were focused on a landing, they had little possibility for an evasive manoeuvre other than a go-around. I imagine the commercial pilots and the tower controller reasonably assumed that the military helicopter would comply. In fact, why would they have any reason to question that assumption?
A question has arisen about night-vision goggles. Were the crew of the military helicopter using these devices? Night Vision Imaging System (NVIS) are not new[2]. They are used in both in military and commercial flying. There are a series of technical requirements that address their safe use. For commercial flying helicopters, that use such visual systems, they must additionally be equipped with a Terrain Avoidance and Warning System (TAWS).
One of the down sides of night-vision systems are that the greatly enhanced capability can lead to overconfidence and potential misjudgements by pilots. When used by pilots these systems amplify ambient light and thus help pilots maintain visual references. That’s good for night flying over difficult terrain at low altitude. It’s not so good when there are multiple bright light sources all around, as there are in a big city.
I’m sure that the accident investigators will be giving the above subject a great deal of consideration. Afterall, the evening of this tragic accident was one of fine weather and fair visibility. The investigators have a significant task ahead analysing data and verifying the performance of both humans and machines in the accident situation.
NOTE 1: Worth a watch https://youtu.be/hlMTpIAlpw0
NOTE 3: Night Flying “there are factors that can make it more challenging, like the lack of visual references and encountering visual illusions”. Flying into the Dark. What You Need to Fly at Night | by FAA Safety Briefing Magazine | Cleared for Takeoff | Jan, 2025 | Medium
[1] Evidence of a last-minute manoeuvre may still come to light. Sadly, the outcome remains the same.
[2] https://skybrary.aero/articles/night-vision-imaging-system-nvis
John Vincent 