14 ms·

Air Traffic Control

264 points by 1317 1y ago

_whiteCaps_ 1y ago
Re WWII use of radio: My grandfather flew Typhoons, and they operated 'cab rank' as part of the 2nd Tactical Air Force. The Army would radio in coordinates of German tanks or fortified positions, and the Typhoons would come in with their rockets / bombs / cannons. I wish he was still around so I could ask him how that was done. A central dispatcher? Or did they talk to the Army directly? Not sure.
- zitterbewegung 1y ago
  Forward air control would get a map grid or other description of the target from Infantry and Aircraft would be dispatched to the target . https://en.wikipedia.org/wiki/Forward_air_control_operations_during_World_War_II?wprov=sfti1#South_Pacific https://en.wikipedia.org/wiki/Forward_air_control_operations...
  - 01HNNWZ0MV43FF 1y ago
    And before GPS they'd reckon their position off of landmarks and terrain?
    - deleted 1y ago
      [deleted]
    - _whiteCaps_ 1y ago
      Yup, and there were apparently fake towns set up with lights that the German night bombers would hit instead of the real populated areas: https://en.wikipedia.org/wiki/Starfish_site https://en.wikipedia.org/wiki/Starfish_site
    - kqr 1y ago
      There was a lot of development around radio navigation aids in the interwar period. I believe it was even possible to navigate using commercial AM radio broadcasts, as long as the location of the broadcasting station was known. So while the basic method was computing location based on speed and compass bearing from a landmark (possibly accounting for wind drift), I believe a certain level of radio navigation was still going on in cases of adverse weather. Longer-range bomber flights also did it the same way ocean-faring ships have done in the past few hundred years: they had a roof window for taking celestial fixes with a sextant. Come to think of it, that's how the Apollo capsule also confirmed its location. There's a lot to read about this. This is probably a good start since it branches to many other related articles: https://en.wikipedia.org/wiki/Oboe_(navigation) https://en.wikipedia.org/wiki/Oboe_(navigation)
      - johannes1234321 1y ago
        > Come to think of it, that's how the Apollo capsule also confirmed its location. Isn't that still how it's done? - When leaving earth orbit there isn't GPS or such, the guidance to the moon or further still uses star trackers.
        AStonesThrow 1y ago
        The Voyager space probes for sure use visual fixes on guide stars, such as Alpha Centauri (and our own Sun?) to ensure correct orientation. Of course, they don't need to navigate much, since given the relative velocities, their thrusters wouldn't make much difference. And there is a quite-famous scene in Apollo 13 where they literally line-up the Moon itself in the reticule so that their engine burn puts them on exactly the correct trajectory.
        SSLy 1y ago
        I believe star maps are also baked into ICBMs
        agurk 1y ago
        Some SLBMs (Submarine Launched Ballistic Missiles) use star sighting to correct their trajectory mid-flight. ICBMs launched from silos know exactly where they're starting from, whereas a submarine is both moving, at different depths and has some error to knowing exactly where it is. Missiles use inertial guidance, so knowing your starting your point is crucial. How accurate a missile needs to be is a whole other dimension though. If the value of a missile is as retaliation to destroy a city (countervalue) then it can be a large warhead and "miss" by quite a margin but needs some form of credible survivability of an enemy first strike. If the missile is to be used to destroy enemy military installations (counterforce) then it needs to be a lot more accurate but usually the implication is as a first strike so less survivability is required. When you have nuclear weapons that you can drop from manned aircraft, ICBMs from silos and SLBMs controlled by different military branches there is going to be a lot of politics over what the missile is for, which will determine its required accuracy, which will be a factor on if it needs star sighting.
    - exidy 1y ago
      There were a great number of inventive aerial navigation systems that predate GPS by many decades. One of my favourite books is Most Secret War[0], a biography by R.V. Jones that details much of the cat and mouse that went into detecting and countering the various systems used by the Axis and the Allies to bomb each other. [0] https://www.goodreads.com/book/show/1127842.Most_Secret_War https://www.goodreads.com/book/show/1127842.Most_Secret_War
    - buildsjets 1y ago
      Armed forces have been using variations of grid maps to plan bombardment since time immemorial. Do you really think that before GPS people just walked around lost all of the time? https://en.wikipedia.org/wiki/Ordnance_Survey_National_Grid https://en.wikipedia.org/wiki/Ordnance_Survey_National_Grid https://en.wikipedia.org/wiki/Military_Grid_Reference_System https://en.wikipedia.org/wiki/Military_Grid_Reference_System
    - Daviey 1y ago
      Dead Reckoning - Pilots have been using this forever (100+ years). It's just maths: speed + heading + time + wind = position. Still widely used in VFR flying! It was made more accessible with the E6B "computer" from the 1930s, but isn't a computer at all - just a circular slide rule with aviation formulas built in and still used today. Every student pilot still learns this stuff. Non-Directional Beacon (NDB) / Automatic Direction Finder (ADF) - Introduced 1930s-40s, standard in WWII. Ground station sends signal, aircraft needle points to it. Pretty simple but not super accurate. Still technically operational but barely used anymore. PPLs still learn it in training but honestly who uses this regularly? It's like knowing how to use a fax machine - technically still around but why would you? Very High Frequency Omnidirectional Range (VOR) & Distance Measuring Equipment (DME) - These work together - VOR gives you direction from a station, DME tells you distance. Developed in the 1940s, and surprisingly still pretty common. Lots of GA pilots use these as primary or backup nav. Created all those "highways in the sky" that formed the airways system. VOR is definitely the most useful of the old-school nav aids, and you'll find these receivers in most cockpits. Inertial Navigation (INS) - Commercial airliners got these in the 1960s. No external signals needed - just measures acceleration to track position changes from your starting point. Completely self-contained, works anywhere on Earth. Modern versions use laser gyros instead of mechanical parts. The drawback is drift - errors add up over time (1-2 miles per hour). Still used alongside GPS on long-haul flights. US Postal Arrows: Also, i've not seen them myself - but the US in the 1920s before radio navigation, the US built a system of MASSIVE concrete arrows (up to 70 feet long!) across the country to guide airmail pilots. This was officially called the "Transcontinental Airway System." They were painted bright yellow and paired with beacons/lighthouses for night flying. The system eventually stretched from NY to SF. Most got dismantled during WWII, but dozens of these concrete arrows still exist today scattered across the western US. It was literally a "follow the yellow brick road" situation for pilots. They'd fly from arrow to arrow during daylight, and at night there were gas powered lights showing them. More info here, https://www.core77.com/posts/25236/what-are-these-giant-concrete-arrows-across-the-american-landscape-25236 https://www.core77.com/posts/25236/what-are-these-giant-conc...
      - HeyLaughingBoy 1y ago
        Until you mentioned the E6B I totally had forgotten that half a lifetime ago, as a student pilot I programmed my Radio Shack Pocket PC to do some of the E6B calculations. It worked, but the usability of the tiny keyboard was crap in a bouncing, vibrating Cessna 152, forcing me to look down at my lap while flying. My instructor once said "you're going to kill yourself using that thing" so I eventually just gave up and bought the electronic E6B.
    - mopsi 1y ago
      In addition to what others have said, letting artillery mark targets with colored smoke and simply flying to a grid location and keeping an eye out for these signals also works well.
- caycep 1y ago
  As an aside, wasn't there some HN post a few months back about how carrier warfare in the Pacific led to more and more complex schemes of ATC, aka "Fighter Directors", including early Naval computers devoted to figuring out where to put airplanes in the right place at the right time right time?
- smdyc1 1y ago
  I read in A Bridge Too Far, the Hawker Typhoons that attacked German positions at the start of the Operation (called in by the Forward Air Comtroller), flew under the opening barrage and one Typhoon disintegrated as it was hit by a shell. I've often wondered if there was any system in place to prevent that sort of thing.
  - smdyc1 1y ago
    I also read there was some difficulty in target designation as the pilots had different maps, so the grid coordinates were off.
  - lmm 1y ago
    Hitting an aircraft in flight was hard enough if you were aiming at it, I doubt they felt any need to take countermeasures against such a rare occurrence.
  - psunavy03 1y ago
    As others have mentioned, in WWII, many of the things modern militaries take for granted were in their infancy. In modern times, there are lots of staff meetings and procedures involving nothing other than deconflicting fires. Fast jets hit this, artillery hits that, fighters cover here, surface-to-air assets cover there, etc. But those lessons are written in blood due to exactly incidents like the one you mention. The "big sky, little airplane" theory is not something to bet your life on.
- rtkwe 1y ago
  The general lack of front line radios makes me think he wouldn't generally have been talking directly to the troops on the ground but the entire field of air combat much less close air support was in it's infancy so a lot of the doctrine was being made up on the fly. By the end of the war they had made a lot of improvements including bringing control of CAS closer to the frontline units that would be calling it in. More about the US side of the conflict: https://www.reddit.com/r/WarCollege/comments/jfrpiu/how_did_cas_work_in_ww2/ https://www.reddit.com/r/WarCollege/comments/jfrpiu/how_did_... Not Europe (assuming from your grandfather flying Typhoons) but here's a paper about how the Marines in the Pacific were developing the idea of close air support in the Pacific: https://apps.dtic.mil/sti/tr/pdf/ADA369287.pdf https://apps.dtic.mil/sti/tr/pdf/ADA369287.pdf A random book I found that might have more specifics about the RAF and British use of CAS: https://crecy.co.uk/product/close-call-raf-close-air-support-in-the-mediterranean-volume-i-defeat-in-france-to-el-hamma-1939-1945 https://crecy.co.uk/product/close-call-raf-close-air-support... Close air support is the phrase you're looking for for your own searches though if he was bombing tanks in the field.
deleted 1y ago
[deleted]
dilap 1y ago
[flagged]
- yujzgzc 1y ago
  That questionnaire looks bad but from these links I didn't see a clear evaluation of impact on hiring number. It doesn't sound like recruitment was going great to begin with?
  - buckle8017 1y ago
    [flagged]
    - deleted 1y ago
      [deleted]
- kevingadd 1y ago
  When your hiring pipeline is so obliterated that you decide to fire about 400 of your employees. Makes sense.
- seliopou 1y ago
  Previous discussion on HN: https://news.ycombinator.com/item?id=42944203 https://news.ycombinator.com/item?id=42944203
- Rebelgecko 1y ago
  That sample hiring quiz (https://kaisoapbox.com/projects/faa_biographical_assessment https://kaisoapbox.com/projects/faa_biographical_assessment) is batshit insane, to the point I can hardly believe it's real (but it seems like it is?)
  - blackguardx 1y ago
    I read through the list. It seems to be standard Meyers-Briggs type questions. I don't think that this is that useful a metric, but I have been given similar questions by private sector companies and was also given a weirder one by the patent office in 2006.
ilamont 1y ago
Kind of curious how air traffic control evolved in other countries, and how the international flight system works with handoffs between countries, particularly in Europe and the Caribbean where national borders tend to be relatively small.
- linschn 1y ago
  This was indeed normalized very early on in post WWII european construction: https://en.m.wikipedia.org/wiki/Eurocontrol https://en.m.wikipedia.org/wiki/Eurocontrol
- ExoticPearTree 1y ago
  In a nutshell it goes like this: you file a flight plan to go from A in country A to B in country B. Every country that you cross will know about this. Depending if you fly IFR or VFR and at what altitude, you will talk to either a flight information service (FIS), Radar or Area Control Center (ACC). Hand-off is usually done a few miles from the border of the next country you're going to pass. You tell them who you are and where you're going to. They can let you fly as planned or give you another route or altitude. From a pilot's point of view is pretty simple and straightforward.
  - aeroevan 1y ago
    How the flights plans get routed is also of interest, they typically go through AFTN: https://en.wikipedia.org/wiki/Aeronautical_Fixed_Telecommunication_Network https://en.wikipedia.org/wiki/Aeronautical_Fixed_Telecommuni...
  - Auracle 1y ago
    How were the flights filed in the pre-internet era?
    - ExoticPearTree 1y ago
      There is standard form that you would fill out at the Briefing office and they would fax it to all relevant parties. Before that, I have no clue if something existed or you would just ring up the destination aerodrome to let them know you're coming.
jillesvangurp 1y ago
The historical perspective is kind of interesting. What interests me more is how this stuff can be modernized. Because the current byzantine system of task saturating people by making them yell numbers and letters at each other over state of the art 1950s technology for doing so is hardly efficient, scalable, or ultimately secure when it inevitably breaks down under the stresses it induces on pilots and staff involved. Communication failures and pilot errors are usually major contributing factors to accidents. Pilot errors become more likely when individuals are preoccupied with processing vast amounts of information and demands thrown at them via radio in critical parts of flight (e.g. when finding their way to a runway). Most of the radio calls today (>95%) are bog standard verbal exchanges about things that should not require any humans in the loop. Anything to with weather is just numbers that can and should be be exchanged digitally. Much faster, less room for error. There should be zero confusion about what the altimeter settings are at a particular airport, what the active runway is, where the wind is coming from, etc. Anything to do with "who are you and why are you here", which is a disturbingly large proportion of verbal exchanges, sounds like it could be established both more securely, robustly, and efficiently. We have computers now with things like secure hashes, uuids, certificates, etc. Any time you have enough bandwidth to talk to somebody you definitely have enough bandwidth to throw quite a bit of data around securely and reliably. If you call your granny via whatsapp, facetime, or whatever, there's no need to tell her who you are. Because the app tells her before she even answers. It's completely redundant information. She already knows. There's no valid technical reason why ATC cannot have the same comfort of knowing who they are talking to and what they are flying. It's 2025! Not 1965. ATC should have full context when they talk to people. They shouldn't have to ask for that context verbally. Routine course changes, altitude changes, etc. could be communicated and confirmed via computers. Voice channels should be used for emergencies and non standard situations only. There are a few things happening in aviation that are making this more urgent after many decades of stagnation in technological changes. Battery electric is going to make flying vastly cheaper and safer than it is today. That's going to increase the amount of relatively inexperienced pilots and plane movements. And secondly, there are an increasing amount of autonomously flying planes, drones, etc. Those are actually going to dominate traffic in the years ahead. Pilots are expensive and are becoming kind of redundant. The amount of flights that ATC needs to juggle is going to increase by at lease one or two orders of magnitude. The current system won't scale with that, it will have to change. Now would be a good time to start figuring that out.
kristel100 1y ago
This piece hit hard. It’s strange how something so invisible to most of us is simultaneously one of the most complex, tightly-coupled systems running in the background of daily life.
- apples_oranges 1y ago
  But is it that complex? Airplanes arrive in your sector, you write the number and destination on a slip of paper, and put it on your board. You tell the plane, if needed, where to fly, and then you tell it to talk to the next sector controller when it leaves your area. It seems rather non-complex, and I think it has to be, so it can be robust and offer room for errors etc.
  - alistairSH 1y ago
    A lot of the complexity is the sheer volume of air traffic. Not so much at cruise, but as planes transit through populated areas. ATC over NorCal is a mess of overlapping zones, ~dozen airports, and hundreds of airplanes at any given time of day. NYC metro is similar.
  - jgeada 1y ago
    Everything is simple at the highest levels of abstraction. It is the details of actually making it work that raise the complexity levels and/or kill you if you don't get them right. Remember: a decision that in the abstract with infinite thinking time is easy can be extremely stressful when it has to be made in seconds in real time and getting it slightly wrong will potentially cause a catastrophe. And ATC has to keep doing this throughout their entire work shift.
    - psunavy03 1y ago
      Standing joke in aviation: what's the same between a pilot and a controller? If they screw up, the pilot dies.
ranger207 1y ago
An interesting parallel to the Air Force's SAGE was the Navy's NTDS, Naval Tactical Data System. It had to do much the same as SAGE, with target correlation and the like, and had to do it from moving ships (and later with the E-2 Hawkeye Airborne Tactical Data System from planes as well). Purely military, and I can't tell that many of its developments ever ended up in civilian society like elements of SAGE did, but it's remarkable just how much they could do with the technology of the time. The best source I've seen about NTDS itself is https://ethw.org/First-Hand:No_Damned_Computer_is_Going_to_Tell_Me_What_to_DO_-_The_Story_of_the_Naval_Tactical_Data_System,_NTDS https://ethw.org/First-Hand:No_Damned_Computer_is_Going_to_T... while Norman Friedman's book _Fighters Over the Fleet_ talks about the fighter control context around NTDS, like what the system was before NTDS, the factors that caused the previous system to break down, and parallel British efforts at the same problem
telotortium 1y ago
Hi author, I love your blog, but could you add a toggle option to disable the background image? I end up going to Chrome Devtools and disabling the CSS rule. I suppose the PDF is a good workaround for now.
- going_north 1y ago
  The RSS feed is another good option!
  - telotortium 1y ago
    That’s true, but I need to set aside time to clean up my RSS reader (too many feeds!).
Caelus9 1y ago
[dead]

264 points by 1317 1y ago

Re WWII use of radio: My grandfather flew Typhoons, and they operated 'cab rank' as part of the 2nd Tactical Air Force. The Army would radio in coordinates of German tanks or fortified positions, and the Typhoons would come in with their rockets / bombs / cannons. I wish he was still around so I could ask him how that was done. A central dispatcher? Or did they talk to the Army directly? Not sure.

zitterbewegung 1y ago
Forward air control would get a map grid or other description of the target from Infantry and Aircraft would be dispatched to the target . https://en.wikipedia.org/wiki/Forward_air_control_operations_during_World_War_II?wprov=sfti1#South_Pacific https://en.wikipedia.org/wiki/Forward_air_control_operations...
- 01HNNWZ0MV43FF 1y ago
  And before GPS they'd reckon their position off of landmarks and terrain?
  - deleted 1y ago
    [deleted]
  - _whiteCaps_ 1y ago
    Yup, and there were apparently fake towns set up with lights that the German night bombers would hit instead of the real populated areas: https://en.wikipedia.org/wiki/Starfish_site https://en.wikipedia.org/wiki/Starfish_site
  - kqr 1y ago
    There was a lot of development around radio navigation aids in the interwar period. I believe it was even possible to navigate using commercial AM radio broadcasts, as long as the location of the broadcasting station was known. So while the basic method was computing location based on speed and compass bearing from a landmark (possibly accounting for wind drift), I believe a certain level of radio navigation was still going on in cases of adverse weather. Longer-range bomber flights also did it the same way ocean-faring ships have done in the past few hundred years: they had a roof window for taking celestial fixes with a sextant. Come to think of it, that's how the Apollo capsule also confirmed its location. There's a lot to read about this. This is probably a good start since it branches to many other related articles: https://en.wikipedia.org/wiki/Oboe_(navigation) https://en.wikipedia.org/wiki/Oboe_(navigation)
    - johannes1234321 1y ago
      > Come to think of it, that's how the Apollo capsule also confirmed its location. Isn't that still how it's done? - When leaving earth orbit there isn't GPS or such, the guidance to the moon or further still uses star trackers.
      - AStonesThrow 1y ago
        The Voyager space probes for sure use visual fixes on guide stars, such as Alpha Centauri (and our own Sun?) to ensure correct orientation. Of course, they don't need to navigate much, since given the relative velocities, their thrusters wouldn't make much difference. And there is a quite-famous scene in Apollo 13 where they literally line-up the Moon itself in the reticule so that their engine burn puts them on exactly the correct trajectory.
      - SSLy 1y ago
        I believe star maps are also baked into ICBMs
        agurk 1y ago
        Some SLBMs (Submarine Launched Ballistic Missiles) use star sighting to correct their trajectory mid-flight. ICBMs launched from silos know exactly where they're starting from, whereas a submarine is both moving, at different depths and has some error to knowing exactly where it is. Missiles use inertial guidance, so knowing your starting your point is crucial. How accurate a missile needs to be is a whole other dimension though. If the value of a missile is as retaliation to destroy a city (countervalue) then it can be a large warhead and "miss" by quite a margin but needs some form of credible survivability of an enemy first strike. If the missile is to be used to destroy enemy military installations (counterforce) then it needs to be a lot more accurate but usually the implication is as a first strike so less survivability is required. When you have nuclear weapons that you can drop from manned aircraft, ICBMs from silos and SLBMs controlled by different military branches there is going to be a lot of politics over what the missile is for, which will determine its required accuracy, which will be a factor on if it needs star sighting.
  - exidy 1y ago
    There were a great number of inventive aerial navigation systems that predate GPS by many decades. One of my favourite books is Most Secret War[0], a biography by R.V. Jones that details much of the cat and mouse that went into detecting and countering the various systems used by the Axis and the Allies to bomb each other. [0] https://www.goodreads.com/book/show/1127842.Most_Secret_War https://www.goodreads.com/book/show/1127842.Most_Secret_War
  - buildsjets 1y ago
    Armed forces have been using variations of grid maps to plan bombardment since time immemorial. Do you really think that before GPS people just walked around lost all of the time? https://en.wikipedia.org/wiki/Ordnance_Survey_National_Grid https://en.wikipedia.org/wiki/Ordnance_Survey_National_Grid https://en.wikipedia.org/wiki/Military_Grid_Reference_System https://en.wikipedia.org/wiki/Military_Grid_Reference_System
  - Daviey 1y ago
    Dead Reckoning - Pilots have been using this forever (100+ years). It's just maths: speed + heading + time + wind = position. Still widely used in VFR flying! It was made more accessible with the E6B "computer" from the 1930s, but isn't a computer at all - just a circular slide rule with aviation formulas built in and still used today. Every student pilot still learns this stuff. Non-Directional Beacon (NDB) / Automatic Direction Finder (ADF) - Introduced 1930s-40s, standard in WWII. Ground station sends signal, aircraft needle points to it. Pretty simple but not super accurate. Still technically operational but barely used anymore. PPLs still learn it in training but honestly who uses this regularly? It's like knowing how to use a fax machine - technically still around but why would you? Very High Frequency Omnidirectional Range (VOR) & Distance Measuring Equipment (DME) - These work together - VOR gives you direction from a station, DME tells you distance. Developed in the 1940s, and surprisingly still pretty common. Lots of GA pilots use these as primary or backup nav. Created all those "highways in the sky" that formed the airways system. VOR is definitely the most useful of the old-school nav aids, and you'll find these receivers in most cockpits. Inertial Navigation (INS) - Commercial airliners got these in the 1960s. No external signals needed - just measures acceleration to track position changes from your starting point. Completely self-contained, works anywhere on Earth. Modern versions use laser gyros instead of mechanical parts. The drawback is drift - errors add up over time (1-2 miles per hour). Still used alongside GPS on long-haul flights. US Postal Arrows: Also, i've not seen them myself - but the US in the 1920s before radio navigation, the US built a system of MASSIVE concrete arrows (up to 70 feet long!) across the country to guide airmail pilots. This was officially called the "Transcontinental Airway System." They were painted bright yellow and paired with beacons/lighthouses for night flying. The system eventually stretched from NY to SF. Most got dismantled during WWII, but dozens of these concrete arrows still exist today scattered across the western US. It was literally a "follow the yellow brick road" situation for pilots. They'd fly from arrow to arrow during daylight, and at night there were gas powered lights showing them. More info here, https://www.core77.com/posts/25236/what-are-these-giant-concrete-arrows-across-the-american-landscape-25236 https://www.core77.com/posts/25236/what-are-these-giant-conc...
    - HeyLaughingBoy 1y ago
      Until you mentioned the E6B I totally had forgotten that half a lifetime ago, as a student pilot I programmed my Radio Shack Pocket PC to do some of the E6B calculations. It worked, but the usability of the tiny keyboard was crap in a bouncing, vibrating Cessna 152, forcing me to look down at my lap while flying. My instructor once said "you're going to kill yourself using that thing" so I eventually just gave up and bought the electronic E6B.
  - mopsi 1y ago
    In addition to what others have said, letting artillery mark targets with colored smoke and simply flying to a grid location and keeping an eye out for these signals also works well.
caycep 1y ago
As an aside, wasn't there some HN post a few months back about how carrier warfare in the Pacific led to more and more complex schemes of ATC, aka "Fighter Directors", including early Naval computers devoted to figuring out where to put airplanes in the right place at the right time right time?
smdyc1 1y ago
I read in A Bridge Too Far, the Hawker Typhoons that attacked German positions at the start of the Operation (called in by the Forward Air Comtroller), flew under the opening barrage and one Typhoon disintegrated as it was hit by a shell. I've often wondered if there was any system in place to prevent that sort of thing.
- smdyc1 1y ago
  I also read there was some difficulty in target designation as the pilots had different maps, so the grid coordinates were off.
- lmm 1y ago
  Hitting an aircraft in flight was hard enough if you were aiming at it, I doubt they felt any need to take countermeasures against such a rare occurrence.
- psunavy03 1y ago
  As others have mentioned, in WWII, many of the things modern militaries take for granted were in their infancy. In modern times, there are lots of staff meetings and procedures involving nothing other than deconflicting fires. Fast jets hit this, artillery hits that, fighters cover here, surface-to-air assets cover there, etc. But those lessons are written in blood due to exactly incidents like the one you mention. The "big sky, little airplane" theory is not something to bet your life on.
rtkwe 1y ago
The general lack of front line radios makes me think he wouldn't generally have been talking directly to the troops on the ground but the entire field of air combat much less close air support was in it's infancy so a lot of the doctrine was being made up on the fly. By the end of the war they had made a lot of improvements including bringing control of CAS closer to the frontline units that would be calling it in. More about the US side of the conflict: https://www.reddit.com/r/WarCollege/comments/jfrpiu/how_did_cas_work_in_ww2/ https://www.reddit.com/r/WarCollege/comments/jfrpiu/how_did_... Not Europe (assuming from your grandfather flying Typhoons) but here's a paper about how the Marines in the Pacific were developing the idea of close air support in the Pacific: https://apps.dtic.mil/sti/tr/pdf/ADA369287.pdf https://apps.dtic.mil/sti/tr/pdf/ADA369287.pdf A random book I found that might have more specifics about the RAF and British use of CAS: https://crecy.co.uk/product/close-call-raf-close-air-support-in-the-mediterranean-volume-i-defeat-in-france-to-el-hamma-1939-1945 https://crecy.co.uk/product/close-call-raf-close-air-support... Close air support is the phrase you're looking for for your own searches though if he was bombing tanks in the field.

deleted 1y ago

[deleted]

dilap 1y ago

[flagged]

yujzgzc 1y ago
That questionnaire looks bad but from these links I didn't see a clear evaluation of impact on hiring number. It doesn't sound like recruitment was going great to begin with?
- buckle8017 1y ago
  [flagged]
  - deleted 1y ago
    [deleted]
kevingadd 1y ago
When your hiring pipeline is so obliterated that you decide to fire about 400 of your employees. Makes sense.
seliopou 1y ago
Previous discussion on HN: https://news.ycombinator.com/item?id=42944203 https://news.ycombinator.com/item?id=42944203
Rebelgecko 1y ago
That sample hiring quiz (https://kaisoapbox.com/projects/faa_biographical_assessment https://kaisoapbox.com/projects/faa_biographical_assessment) is batshit insane, to the point I can hardly believe it's real (but it seems like it is?)
- blackguardx 1y ago
  I read through the list. It seems to be standard Meyers-Briggs type questions. I don't think that this is that useful a metric, but I have been given similar questions by private sector companies and was also given a weirder one by the patent office in 2006.

ilamont 1y ago

Kind of curious how air traffic control evolved in other countries, and how the international flight system works with handoffs between countries, particularly in Europe and the Caribbean where national borders tend to be relatively small.

linschn 1y ago
This was indeed normalized very early on in post WWII european construction: https://en.m.wikipedia.org/wiki/Eurocontrol https://en.m.wikipedia.org/wiki/Eurocontrol
ExoticPearTree 1y ago
In a nutshell it goes like this: you file a flight plan to go from A in country A to B in country B. Every country that you cross will know about this. Depending if you fly IFR or VFR and at what altitude, you will talk to either a flight information service (FIS), Radar or Area Control Center (ACC). Hand-off is usually done a few miles from the border of the next country you're going to pass. You tell them who you are and where you're going to. They can let you fly as planned or give you another route or altitude. From a pilot's point of view is pretty simple and straightforward.
- aeroevan 1y ago
  How the flights plans get routed is also of interest, they typically go through AFTN: https://en.wikipedia.org/wiki/Aeronautical_Fixed_Telecommunication_Network https://en.wikipedia.org/wiki/Aeronautical_Fixed_Telecommuni...
- Auracle 1y ago
  How were the flights filed in the pre-internet era?
  - ExoticPearTree 1y ago
    There is standard form that you would fill out at the Briefing office and they would fax it to all relevant parties. Before that, I have no clue if something existed or you would just ring up the destination aerodrome to let them know you're coming.

jillesvangurp 1y ago

The historical perspective is kind of interesting. What interests me more is how this stuff can be modernized. Because the current byzantine system of task saturating people by making them yell numbers and letters at each other over state of the art 1950s technology for doing so is hardly efficient, scalable, or ultimately secure when it inevitably breaks down under the stresses it induces on pilots and staff involved. Communication failures and pilot errors are usually major contributing factors to accidents. Pilot errors become more likely when individuals are preoccupied with processing vast amounts of information and demands thrown at them via radio in critical parts of flight (e.g. when finding their way to a runway). Most of the radio calls today (>95%) are bog standard verbal exchanges about things that should not require any humans in the loop. Anything to with weather is just numbers that can and should be be exchanged digitally. Much faster, less room for error. There should be zero confusion about what the altimeter settings are at a particular airport, what the active runway is, where the wind is coming from, etc. Anything to do with "who are you and why are you here", which is a disturbingly large proportion of verbal exchanges, sounds like it could be established both more securely, robustly, and efficiently. We have computers now with things like secure hashes, uuids, certificates, etc. Any time you have enough bandwidth to talk to somebody you definitely have enough bandwidth to throw quite a bit of data around securely and reliably. If you call your granny via whatsapp, facetime, or whatever, there's no need to tell her who you are. Because the app tells her before she even answers. It's completely redundant information. She already knows. There's no valid technical reason why ATC cannot have the same comfort of knowing who they are talking to and what they are flying. It's 2025! Not 1965. ATC should have full context when they talk to people. They shouldn't have to ask for that context verbally. Routine course changes, altitude changes, etc. could be communicated and confirmed via computers. Voice channels should be used for emergencies and non standard situations only. There are a few things happening in aviation that are making this more urgent after many decades of stagnation in technological changes. Battery electric is going to make flying vastly cheaper and safer than it is today. That's going to increase the amount of relatively inexperienced pilots and plane movements. And secondly, there are an increasing amount of autonomously flying planes, drones, etc. Those are actually going to dominate traffic in the years ahead. Pilots are expensive and are becoming kind of redundant. The amount of flights that ATC needs to juggle is going to increase by at lease one or two orders of magnitude. The current system won't scale with that, it will have to change. Now would be a good time to start figuring that out.

kristel100 1y ago

This piece hit hard. It’s strange how something so invisible to most of us is simultaneously one of the most complex, tightly-coupled systems running in the background of daily life.

apples_oranges 1y ago
But is it that complex? Airplanes arrive in your sector, you write the number and destination on a slip of paper, and put it on your board. You tell the plane, if needed, where to fly, and then you tell it to talk to the next sector controller when it leaves your area. It seems rather non-complex, and I think it has to be, so it can be robust and offer room for errors etc.
- alistairSH 1y ago
  A lot of the complexity is the sheer volume of air traffic. Not so much at cruise, but as planes transit through populated areas. ATC over NorCal is a mess of overlapping zones, ~dozen airports, and hundreds of airplanes at any given time of day. NYC metro is similar.
- jgeada 1y ago
  Everything is simple at the highest levels of abstraction. It is the details of actually making it work that raise the complexity levels and/or kill you if you don't get them right. Remember: a decision that in the abstract with infinite thinking time is easy can be extremely stressful when it has to be made in seconds in real time and getting it slightly wrong will potentially cause a catastrophe. And ATC has to keep doing this throughout their entire work shift.
  - psunavy03 1y ago
    Standing joke in aviation: what's the same between a pilot and a controller? If they screw up, the pilot dies.

ranger207 1y ago

An interesting parallel to the Air Force's SAGE was the Navy's NTDS, Naval Tactical Data System. It had to do much the same as SAGE, with target correlation and the like, and had to do it from moving ships (and later with the E-2 Hawkeye Airborne Tactical Data System from planes as well). Purely military, and I can't tell that many of its developments ever ended up in civilian society like elements of SAGE did, but it's remarkable just how much they could do with the technology of the time. The best source I've seen about NTDS itself is https://ethw.org/First-Hand:No_Damned_Computer_is_Going_to_Tell_Me_What_to_DO_-_The_Story_of_the_Naval_Tactical_Data_System,_NTDS https://ethw.org/First-Hand:No_Damned_Computer_is_Going_to_T... while Norman Friedman's book _Fighters Over the Fleet_ talks about the fighter control context around NTDS, like what the system was before NTDS, the factors that caused the previous system to break down, and parallel British efforts at the same problem

telotortium 1y ago

Hi author, I love your blog, but could you add a toggle option to disable the background image? I end up going to Chrome Devtools and disabling the CSS rule. I suppose the PDF is a good workaround for now.

going_north 1y ago
The RSS feed is another good option!
- telotortium 1y ago
  That’s true, but I need to set aside time to clean up my RSS reader (too many feeds!).

Caelus9 1y ago

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