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It's really surprising how many mid air collisions happen given the
fact that there are 3 dimensions in which to avoid contact. I think
that a significant percentage of these can be attributed to altitude
fixation.
What is altitude fixation? It's when a pilot or air control chooses an
easy
or common altitude. Ex "I will fly at 12,000ft" instead of
11,800ft. Many people will pick the "easier" number. That could
be
a fatal mistake. Two aircraft at intersecting paths at 12,000ft is
fatal. Two aircraft intersecting 200ft vertical separation is scary,
but perfectly survivable.
Possible solutions:
- In flight random number generator. Key in 12,000 and it will spit
up
a close enough random number +/- 500ft. That way you avoid
multiple pilots trying to be random at 12,000ft and they all
happen
to randomly pick 11,800 (there is no such thing as random if it
comes
from a human mind)
- Altitude broadcast. Have every aircraft carry a simple device.
All it
does it broadcast aircraft's height to other aircraft within 5
nautical
miles of each other. Just make sure that their altitude never
matches
your altitude and you will be safe no matter where they are x,y
coordinate-wise.
- Some kind of altitude offset system. Ex: aircraft registration num
->
md5 sum -> decimal -> trim excess digits = altitude offset. So
let's
say G-KHMR has offset of +120 ft, the pilot will always fly at
whatever height they normally should +120ft. Everyone would use
the same calculation and the result would be more or less random
flight paths. This gives new meaning to the term hash collission.
Important note, I realize that aviation needs precision. A random
altitude will likely make any air traffic controller shiver - and
rightfully so. Complete randomness is not the answer, but
neither is
complete precision. Complete precision can be fatal. How much
randomness will save lives vs cause additional crashes could be
determined by empirical studies. Do we need 200ft random
altitude
separation? Or is it 1000ft?
[link]
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[+] though I'm sure it's usually more complicated than aircraft colliding because they both chose the same easy to remember altitude. |
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//more complicated than aircraft colliding because they
both chose the same altitude |
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For sure, aircraft collide because crossing x,y coordinates
and this idea nothing to stop that. This is a failsafe. Let's
say air traffic screws up and lets two aircraft cross
paths,now at least they won't hit. Think about this as an
extra layer of safety, not a replacement. |
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500 feet separation is the law - and it's ABSOLUTELY NOT
random. Eastbound gets odd thousands; westbound is
even
thousands. If you're on VFR, you get 500 feet higher. |
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(These are US rules. If I understand correctly, the UK and
some other countries use a quadrantal rule for
altitude assignment.) |
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Random altitudes would only be slightly less deadly than
just blowing up the planes on the ground. |
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(You may also want to find out about ADS-B and TCAS...) |
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What about a convention where the direction of flight is associated with an altitude. North=1km, North east = 1.1km, etc. |
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This might also be useful for UAVs that will soon fill the skies delivering packages etc. |
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The trick, surely, is to re-introduce the serving of
cocktails on the flight deck. What are the odds of
two aircraft, both piloted by slightly squiffy pilots,
both being at exactly their intended altitude at the
same time, and in the same place? |
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If we have cars which can drive autonomously then really how hard can it be to triangulate moving or stationary obstacles in the air and actively avoid them in case of human error? If one zigs the other has to zag. What's the hold up? Does it infringe too much on missile avoidance patents or something? |
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// What are the odds of two aircraft, both piloted by slightly squiffy pilots, both being at exactly their intended altitude at the same time, and in the same place? // |
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Higher than you might think. Some pilots (naming no names, but you know who you are*) tend to get argumentative and beligerent when drunk, and squabble over the controls. The resulting rollercoaster trajectory probably increases rather than reduces the chances of collision. |
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*And we're still waiting for you to return the gust lock. And our 'plane may be older than yours, but at least we look after it, and it has a windscreen clean of bug splash. Oh, and next time you make a crack like that in the Club bar, make sure your friends are there. If you have any, which we doubt. |
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Concorde had a couple of neat tricks for avoiding mid air
collisions. Firstly, by simply inserting an additional 3.5
vertical miles between itself and the riff-raff traffic
collisions were never a problem. Secondly, by travelling
much much faster, the aircraft was in the air for less time.
It's very difficult to suffer the uncomfortable consequences
of a mid-air collision when you've been safely ensconced in
an agreeable cocktail lounge for an hour. |
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Just allow pilots to install air-to-air missiles. The resulting
arms race will make knowing where other planes are the
least of their worries. |
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Don't the majority of mid-air collisions actually happen close
to the airport, as part of departure or approach? Or as part
of airshows. I'm sure there have been a few well away from
the airport, but the only one I can think of was sightseeing
over the grand canyon. |
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That's true. You are most likely to die in airplane
within 3 miles of your point of departure or your
destination. So you should really consider flying
somewhere else. |
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Again, I think they're dealing with this. If your
destination is London, they very cleverly fly you miles
away from it. Kent, Bishops Stortford or even Luton. |
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