Posts about: "Wikipedia" [Posts: 9 Page: 1 of 1]¶

Putting humans in situations where failing to notice something results in catastrophic consequences is bad engineering, not human error. I am very glad that no-one is pointing at one, or either, pilot or flight-crew's actions or inactions and saying pilot/human error.

The human visual system is good at picking up movement across the visual field. As other have pointed out, if the two aircraft were on intersecting vectors, there would be no relative movement to be picked up. Bright(er) lights don't help: if anything, they make it harder to make out the source from the background, as the bright light makes the local background look like a uniform dark field.

From a 'human factors' point of view, if you have an incorrect situational awareness model in your consciousness, it is difficult to remain flexible enough to recognise you might be wrong - misidentifying the next in sequence, AAL3130, landing runway 1, as the CRJ (IF that is what happened) is hard to recover from.

We should not blame the flight-crews. We should not engineer them into situations where incorrect interpretation of what were likely inputs that were easy to interpret in more than one way become catastrophic. The problem is not restricted to air-navigation. One of the many reasons Norway lost the frigate Helge Ingstad in a collision was misidentification of a moving object (a brightly lit oil tanker) as a stationary object (an oil terminal), and incorrectly ascribing radio transmissions as coming from other moving ships in the vicinity,

We should look at how to engineer things better to avoid this happening: this does not mean 'more training', 'brighter lights', or putting additional human-operated steps in already complex procedures.

Umm, no. DCA and IAD are both operated by the Metropolitan Washington Airports Authority. The real estate itself is still owned by the US Government (via the Department of Transportation, I think). Per the Wikipedia entry:

It's an interesting comparison, but I am not sure it's fair to say that a controller would know that visual separation at night is unsafe or appreciate the counterintuitive point that NVG make it less safe. Of course, they *should* know, but since they don't need to have night flying (or any flying) experience of their own, they are reliant on being educated on that point. That would be a matter for the regulator (specifically, pilots and human factors specialists within the regulator) to ensure. The same goes for the more robust option of prohibiting night visual separation entirely.
Returning to your doctor analogy: if front line medics prescribed a drug which years later turned out to be harmful to patients, despite following all professional best practice and having no reason at the time to suspect that the drug had been wrongly certified, it would be grossly unfair to hold the medics responsible. Instead we would turn to the drug regulator and those who carried out the trials.

Playing Devil's Advocate for a moment, if the heliroutes are published for the common sense use of participants, not for the protection of air transport, and we further accept that it is not within the purview of ATC to question the discretion of willing users, I'm afraid we can only fall back on this accident being the sole responsibility of the helicopter. Which I guess is is another way of re-stating your last post.

I wouldn't put it past the FAA to pull a stunt like that, read Mary Schiavo's (ex IG of the Dept. of Transportation) book if you want to know how wily they can be. And Jennifer gave them the perfect lay up in the last briefing.

If you put bad data into the best computer in the world, you will get bad data coming out of it. I would rather set the blame to the procedure designers and those who approved these Heliroutes.
It's way to easy to blame the pilots, over the years there have been incidents due to incorrect QNH settings, were both pilots and ATC have failed to catch the error, in a busy airspace with overworked ATC, late change of runway for airlines, and military helicopters using Night Vision Goggles, altimeter equipment failure/error.

Even the Max 200 ft altitude under the approach to a major US airport is an accident waiting to happen, and whoever approved this to be used during normal operations should be investigated. The CRJ was at around 325 ft on a visual/circling approach when it crashed, does anyone really think it's great airmanship to have a Black Hawk helicopter at 200 ft passing under you?

That's what made the Swiss Cheese model line up perfectly, a planned approved separation of 125 ft was the "best case" scenario.

There you go. A bit of work with google is never time wasted. I offered an opinion about the extent to which the NTSB might be incentivised to explore issues of the mission of the FAA, and like all opinions, it resides in the domain of politics. That's a possible reason why the NTSB might not choose to go there. However an ex-Inspector General of the Dept of Transportation had strong views on the subject, and I give a lot of weight to her opinion, supported as it is by her personal experiences of dealing with the FAA.

Frankly, a lot of lessons shown in rail accident reports from the 1800s still haven't fully been learnt outside the rail industry. Aviation is unforgiving of mechanical failures but rail is equally unforgiving of procedural failures.

https://en.wikipedia.org/wiki/Clayton_Tunnel_rail_crash

For the extreme option , here's a projection onto a water curtain:



The classic 11'8" bridge of youtube fame has overheight lights. The bridge has since been slightly raised and the warning systems improved but still gets people driving straight through them.



Even the London Underground has frangible fittings to detect taller surface stock trains incorrectly approaching a deep-level tube tunnel, throwing signals to danger and thus raising trainstops, which if passed apply the emergency brakes. The latter is important, because SPADs (Signal Passed At Danger) are still not uncommon.


They're not everywhere. It's a risk analysis based mainly on the inconvenience and cost of the cleanup and closure for the bridge/tunnel, and how many overheight vehicles are actually impacting the obstacle. They also don't work especially well because people assume the overheight warning couldn't possibly apply to them .

There's probably some degree of tolerance involved; e.g. bridge marked at 4.4m, sensors at 4.6m, bridge is actually 4.8m. I'm not sure what the actual standards are.

Big bus for the Concorde accident WillowRun 6-3 :
https://en.wikipedia.org/wiki/Air_Fr..._investigation Continental still retained the civil liability.