I second that. The current separation levels are safe, but already quite small. I think that as far as basic altitude/direction rules are concerned, we can't go far beyond the current system of routes, vertical separation and route directions. ONly with advanced transponder/TCAS systems such as Free Flight will we be able to use the airspace in a different way, namely as... free flight.

In theory. Though simulations did show potential, especially around airports. And it would make the task of traffic control easier. Basically you'd need Tower, and all other ATC would be backup/special purposes. The basic ATC would be contained in the aircraft itself.

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Jolly good idea that! Vary height slightly
according to compass heading. Well done

Not so jolly good as it seems. You are not solving many intrusion issues, and it gets massively impractical when descending or ascending. If you do not make those impractical spirals, you'd once again need the amount of ATC you have to day, so in practice you don't solve anything. On top of that, as explained, this results in low vertical separation (unless you want to kill cruise efficiency), which is extremely dangerous as altimeters and flight level control aren't very precise.

UNtil things such as Free Flight are made, the current system of routes + route direction flight levels seems more practical to me. I think that even with a ''perfect'', for example GPS based altimeter (assuming it works nice vertically), I don't think it is very safe to reduce the current 300m vertical separation minimum a lot. Even in systems such as Free Flight, I think that 300m will be about the height of 2 half bubbles in cruise. Of course it depends on aircraft and flight regime.

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Flight controllers to be charged(*) by the Brazilian analogue of the FBI. Link (if you fancy Portuguese...)

(*) However there are indications that the transponder on the Legacy jet was turned-off. The pilots are cleared so far.

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Update:

The American pilots of the Legacy jet were cleared of the negligence charges by a Brazilian court last monday.

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Bravo to the Brazilian court. From what I remember of the incident, they made the right decision.

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Wasn't this accident featured in an "Aircrash Investigations" or similar show episode recently? IIRC in what I saw there was an unfortunate set of circumstances that led to the transponder being off, but I'm not too sure of my memory.

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It´s interesting that the National Civilian Aviation Agency investigation commission concluded that the pilots failed to proceed in accordance to best practices. The commission has said:

.The pilots were not acquainted with each other.
.They were not totally comfortable with the Legacy
.They knew little about the Brazilian air space
.They let themselves to be hurried by the passengers
.They did not have an adequate Flight Plan

The flight controllers also had their share of guilt:

.They did not provide adequate information
.They did not act upon noticing that the plane was at a wrong altitude [for instance, demanding that they turned the transponder on]

As usual, the objective of the investigation was to identify causes and not to assign blames.

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Few things. First; I hadn't followed this thread throughout. Argos, thanks for all the great updates as the story progessed; it's not often that I can get myself to read through multiple pages of a thread that I hadn't been a part of.

Secondly; it sounds like the tragedy was used to initiate much needed change. I wish that was always the case; all too often excuses are made, but the broken things are left untouched.

I noted that you said you see a lot of people with negative biases towards Brazil. I think that's odd (but I'm not saying I don't believe you). I love the country in that, while I've never been there, the few people I've me from Brazil are among the nicest people I've ever known. One of the guys I went through the Academy with grew up in Brazil. He was impossible not to like. That's why, when he ended up getting a job with the same security company, and eventually becoming one of "my guards" (I was site manager, they put him at my site) I had mixed feelings. It was awsome to see him again and loved working with him; but felt the job was soo much below his abilities.

He was still working for that company when I quit and took over as a sergent for a bigger site. I haven't seen him since; hope he's doing okay.

Lastly, I might have missed it in trying to catch up on the thread. I thought early on the pilots were detained and not allowed to leave the country pending the investigation. If they were just recently cleared, have they been held there for all this time?

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I'm like one of those idiot savants...well, except for the savant part.
Ignore enough evidence and anything can be called mysterious or unexplained.

Yes, they have overhauled the entire system, from the management to the hardware, including the allocation of more radars to the region [though it´s been concluded that there was adequate coverage - now part of the military early warning system in the Amazon is committed to the civilian traffic].

Thanks for the words, Fazor. Brazilians are generally easy-going folks; it´s part of the national character. Maybe I have a bias to see biases.

No, no. They were released a couple of days later. AFAIK, during the judgment process they remained in the US, and were heard via letters rogatory.

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Ah, I figured as much but was just checking. Being trapped in a forign country for years while a highly political investigation ensues sounded like a good movie plot though.

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I'm like one of those idiot savants...well, except for the savant part.
Ignore enough evidence and anything can be called mysterious or unexplained.

Yeah. It reminds me of The Midnight Express.

Actually, the whole judgment was highly technical and did not suffer from political interferences.

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The result was; but it sounded like there was a lot of initial finger-pointing the first few days following the collision, but that's not unusual. But I meant for the purposes of a movie script.

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I'm like one of those idiot savants...well, except for the savant part.
Ignore enough evidence and anything can be called mysterious or unexplained.

However, I also read they're still considering involuntary manslaughter charges.

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Link

Under the Roman Right rationale [which is the basis for the law here] an involuntary action can only result from a) unskillfulness, b) inprudence, or c) negligence. Since they have been acquitted of negligence, then there are no grounds for a manslaughter charge.

However, the prosecutors could indeed appeal to a superior court [although it´s not likely].

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