Text Based ATC Communications for GA

Bruce,

CPDLC is alive and well and being used extensively around the world. Here is a link to a technical document (pdf) that explains how it works.

http://www.icao.int/NACC/Documents/Meetings/2014/AUTOSWIM/AUTOSWIMP14.pdf

I have it in my work airplane (G550) and just got the LOA to be able to use it. It is extremely helpful when flying in areas where voice communication is spotty (oceanic) and/or the language barrier is evident.

This said, we are many years away from it being useful to the masses in the US. The equipment is very costly and for the most part, voice communication is excellent in the US.

Kevin
 
NEXGEN which ADSB is a part of is multifaceted. In a slow ATC environment, text based communication will work. In the real ATC environment it won't. Speed of issuance being disregarded think about the last time you as a pilot heard a terrain or traffic alert. Tone of voice says everything and unless we break down how many !!!'s it takes to convey urgency.

On a similar note, if you're a regular and I'm busy I barely have to enunciate. "Seed wreck ABC Art ABC two zero zero." Type that? Proceed direct ABC. depart ABC heading two two zero. Or will the far AIM adapt so I can text ABC M8?

NEXGEN isn't fully here, its a great idea but it lags behind. We have it here in fusion. Three RADAR sets giving us an ultra accurate real time picture of where you are. Works well until planes start moving backwards when different sites disagree.

Aaaaand believe me the targets jump up to two miles erratically in one second. So much so that I've turned an MD80 base and 30 seconds later he's back where he was 60 seconds ago. Its like vectoring in a time machine.

Spot on about voice comm in busy terminal airspace.

As to those fusion glitches, first I've heard, but I am not surprised. Processed radar can't really be better than the source. Especially when mixing ASR and ARSR.
 
Bruce,

CPDLC is alive and well and being used extensively around the world. Here is a link to a technical document (pdf) that explains how it works.

http://www.icao.int/NACC/Documents/Meetings/2014/AUTOSWIM/AUTOSWIMP14.pdf

I have it in my work airplane (G550) and just got the LOA to be able to use it. It is extremely helpful when flying in areas where voice communication is spotty (oceanic) and/or the language barrier is evident.

This said, we are many years away from it being useful to the masses in the US. The equipment is very costly and for the most part, voice communication is excellent in the US.

Kevin

CPDLC is really meant to provide relief from HF.
 
NEXGEN which ADSB is a part of is multifaceted. In a slow ATC environment, text based communication will work. In the real ATC environment it won't. Speed of issuance being disregarded think about the last time you as a pilot heard a terrain or traffic alert. Tone of voice says everything and unless we break down how many !!!'s it takes to convey urgency.

On a similar note, if you're a regular and I'm busy I barely have to enunciate. "Seed wreck ABC Art ABC two zero zero." Type that? Proceed direct ABC. depart ABC heading two two zero. Or will the far AIM adapt so I can text ABC M8?

You're assuming in the system of the future, that you will have to be a Qwerty keyboard and typing in the clearances. That would be slow and likely prone to errors as well. No, I imagine a system much like we have now for flight planning in something like Fore Flight.

A touch screen interface where you put you finger on the plane you want to send a course change, or further clearance to and then simply touch the rest of route way points. It would also have rubber banding capability. When the new course looks correct to you, you push "send" to the aircraft. The pilot pushes "activate" on his end and the route is activated on both ends.

In addition, routes that you repetitively give to people day in and day out could be saved in a "favorites" side bar. Touch the plane on the screen and then the desired route from the favorites list. Done. Faster than you can speak it. Also, the computer can anticipate many of these routine arrivals and departures and suggest and/or load them automatically just requiring your approval.

Like I said above, I don't envision 100% replacement of verbal communications. Like you pointed out, in the case of terrain warning, traffic conflicts, planes with emergencies, voice communications will always be the fastest and most effective way to transmit information. I see no demise in radio communications in my life time.

Less talk, more doing.
 
I actually think terrain and traffic alerts would be best applied with text. The computer (MSAW or CA) could automatically send a message to the pilot without any controller interface.

Also agree with approach, that in a busy terminal environment voice is best.

Touch screen? I used that stuff in tactical ATC but we're decades from that. No money.
 
I actually think terrain and traffic alerts would be best applied with text. The computer (MSAW or CA) could automatically send a message to the pilot without any controller interface.

Also agree with approach, that in a busy terminal environment voice is best.

Touch screen? I used that stuff in tactical ATC but we're decades from that. No money.

The Garmin G-5000 in the Cessna Sovereign has two touch screen input devices for each pilot.
 
The Garmin G-5000 in the Cessna Sovereign has two touch screen input devices for each pilot.

Sure the GTNs are touch screen as well. I'm referring to an ATC system based on touchscreen to issue control instructions to aircraft. In order for all this text fantasy to work, you need touchscreen with a huge software upgrade and electronic flight progress strips. I don't know of any touchscreen systems other than the military tactical environment and outside of Europe and a few other countries, I don't know of any facilities in the US using electronic flight progress strips. We're talking FAA here, where just upgrading from analog ASR-9s to ASR-11 radar systems took forever. Now we're wanting touchscreen displays in an organization just struggling to meet the basic NEXTGEN ADS-B out requirements? It's gonna take at least a couple decades to get to that level.
 
Sure the GTNs are touch screen as well. I'm referring to an ATC system based on touchscreen to issue control instructions to aircraft. In order for all this text fantasy to work, you need touchscreen with a huge software upgrade and electronic flight progress strips. I don't know of any touchscreen systems other than the military tactical environment and outside of Europe and a few other countries, I don't know of any facilities in the US using electronic flight progress strips. We're talking FAA here, where just upgrading from analog ASR-9s to ASR-11 radar systems took forever. Now we're wanting touchscreen displays in an organization just struggling to meet the basic NEXTGEN ADS-B out requirements? It's gonna take at least a couple decades to get to that level.

I missed your point.

Indeed, the FAA is pathetic. They went hog-wild prompting WAAS in general and LPV in particular. Now, they have issued a decree to not develop any new WAAS approaches before 2017 because of budgetary limitations.
 
Touch screen? I used that stuff in tactical ATC but we're decades from that. No money.

No illusions here. There is never money for GA. There is never a need to do anything for GA. There never will be. If we can tag along, borrowing the stuff the airlines get, fine. If not, tough luck. Even the airlines only get upgrades when they can prove it to be seriously beneficial to them and passenger safety.

Private planes flying in clouds is nice luxury, but in the big scheme of things, it is not required or valued by the country and we're lucky we get to do it at all. They could ban all private aviation from the ATC system tomorrow and it would make almost zero difference to the economy, the GDP, or the general public. We are damn lucky to have the crappy 1970's system we do have and access to it!

This is just a dreamer "What if..." thread. Nothing more. No one should feel threatened, or afraid of some big technological change. It's coming at a glacial pace, or not at all. If we're super lucky, GA and private ownership of airplanes will still exist by 2050 and by then, we should have 2010 technology in place.
 
Let me correct myself. In the example I gave it was more like 20 seconds, not 60 seconds and I apologize for the error. The problem was I was slam dunking the guy (IE saving him 40 flying miles) on an established final. I have perimeters to be met to run an ILS and if I'm trying to shoot a gap 20 seconds is a mile. If I need 2.5 miles and I'm thinking I'll have 2.6 and I've lost one, well it won't be pretty. Likely it was a disagreement between radar sites, but it can very much be like working with a bi polar spouse.

Also, in order, Dave I wish I had a QWERTY keyboard in the TRACON. I don't, nor do I anticipate one. Its ABCDEF circa 1978. Mcfly, trust me, you don't want all the false CACA's and LALA's we get. MSAW processing is fine, but it can be a major annoyance.
 
No illusions here. There is never money for GA. There is never a need to do anything for GA. There never will be. If we can tag along, borrowing the stuff the airlines get, fine. If not, tough luck. Even the airlines only get upgrades when they can prove it to be seriously beneficial to them and passenger safety.

Private planes flying in clouds is nice luxury, but in the big scheme of things, it is not required or valued by the country and we're lucky we get to do it at all. They could ban all private aviation from the ATC system tomorrow and it would make almost zero difference to the economy, the GDP, or the general public. We are damn lucky to have the crappy 1970's system we do have and access to it!

This is just a dreamer "What if..." thread. Nothing more. No one should feel threatened, or afraid of some big technological change. It's coming at a glacial pace, or not at all. If we're super lucky, GA and private ownership of airplanes will still exist by 2050 and by then, we should have 2010 technology in place.

GA is worth 150 Billion to the economy as of last year. If you don't mind a video from NATCA's communicating for Safety, skip to about 1:30 if you're pressed for time.

https://www.youtube.com/watch?v=4ra_wrgVna0
 
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How?:dunno: People are crying right now over having to spend $3k to get compliant for below FL180, how are you going to sell even more? Why would we pay for ATC ability and equipment 10% of pilots spring for the ability to take advantage of? Look at what was spent on the SVT database vs. usage. ATC already has a datalink system for airliners, I don't see a value in providing one for GA when the pilots are too cheap to take advantage. It's a waste of resource.

That may be the case now, but the datalink for all is inevitable...whether in five years, fifteen years or whatever.
 
Let me correct myself. In the example I gave it was more like 20 seconds, not 60 seconds and I apologize for the error. The problem was I was slam dunking the guy (IE saving him 40 flying miles) on an established final. I have perimeters to be met to run an ILS and if I'm trying to shoot a gap 20 seconds is a mile. If I need 2.5 miles and I'm thinking I'll have 2.6 and I've lost one, well it won't be pretty. Likely it was a disagreement between radar sites, but it can very much be like working with a bi polar spouse.

Also, in order, Dave I wish I had a QWERTY keyboard in the TRACON. I don't, nor do I anticipate one. Its ABCDEF circa 1978. Mcfly, trust me, you don't want all the false CACA's and LALA's we get. MSAW processing is fine, but it can be a major annoyance.


Whew! That's better. I guess 20 seconds is workable ... :rolleyes2:

The reason GA is dying and can't get with the program and get datalink and other good programs implemented quickly is government involvement plain and simple.

If we got government out of the way, the private sector would vette out what works and what doesn't work real quick. jmho :redface:
 
Whew! That's better. I guess 20 seconds is workable ... :rolleyes2:

The reason GA is dying and can't get with the program and get datalink and other good programs implemented quickly is government involvement plain and simple.

If we got government out of the way, the private sector would vette out what works and what doesn't work real quick. jmho :redface:

I know this isn't the forum to argue this, but if the private sector is involved, it doesn't matter what works, profit matters. I won't argue at all that parts and the infamous FAA tax on an FAA approved Q Tip running 5 bucks per stick is insane.

I will however tell you about a story I've told here before. One about having to call in severe rime on my cell phone on break. The reason was because I as a controller on position got the freaking run around because well, Lock Mart staffs to minimums (that was a government function back during 2003). It was like speaking to the cable company. "Hey man you're last on my dial list to call, severe rime PIREP", uh dial 12 again I'm too busy. "Uh yeah that lines been ringing for 5 minutes."

Just so you know, they consolidated probably 40 AFSS stations down to 3. There was a problem at the start where a pilot would call for a brief on their cell. Area code routed them to New England and they asked for a brief to Smithtown. Clear and VMC says the brief and off they go. Turns out they were in Smithtown Oregon, not Vermont. People died that way.

Seriously, if you are gung ho about privatization spend 8 hours in the rat urine infested hallways of a 60 year old contract tower with the only controller on duty for the next 8 hours. The sink doubles as the urinal. Don't be shy.
 
Even the airlines only get upgrades when they can prove it to be seriously beneficial to them and passenger safety.


Bwahaha. Passenger safety. Yeah that's it.

Not cramming 100 more aircraft an hour into the hubs.

Oh man, my sides hurt from laughing. ;)
 
Whew! That's better. I guess 20 seconds is workable ... :rolleyes2:

The reason GA is dying and can't get with the program and get datalink and other good programs implemented quickly is government involvement plain and simple.

If we got government out of the way, the private sector would vette out what works and what doesn't work real quick. jmho :redface:

The problem is, when it is left to the private sector to 'vette things out' it's usually a process of vetting out the causes of catastrophes after they occur. The most profitable solution is not always the best one.
 
GA is worth 150 Billion to the economy as of last year. If you don't mind a video from NATCA's communicating for Safety, skip to about 1:30 if you're pressed for time.

https://www.youtube.com/watch?v=4ra_wrgVna0

That's great but, with economy the size of ours, it can easily absorb a $150 billion revenue loss. Like I said, the overall economy, the GDP and general public wouldn't even know we were gone. Anyhow, I said ban all private aviation from using ATC services, not ban all private aviation. So there would still be VFR traffic not talking to ATC in my little scenario.
 
NEXGEN which ADSB is a part of is multifaceted. In a slow ATC environment, text based communication will work. In the real ATC environment it won't. Speed of issuance being disregarded think about the last time you as a pilot heard a terrain or traffic alert. Tone of voice says everything and unless we break down how many !!!'s it takes to convey urgency.

On a similar note, if you're a regular and I'm busy I barely have to enunciate. "Seed wreck ABC Art ABC two zero zero." Type that? Proceed direct ABC. depart ABC heading two two zero. Or will the far AIM adapt so I can text ABC M8?

NEXGEN isn't fully here, its a great idea but it lags behind. We have it here in fusion. Three RADAR sets giving us an ultra accurate real time picture of where you are. Works well until planes start moving backwards when different sites disagree.

Aaaaand believe me the targets jump up to two miles erratically in one second. So much so that I've turned an MD80 base and 30 seconds later he's back where he was 60 seconds ago. Its like vectoring in a time machine.

When I read this it makes me laugh.

When I was doing ADS-B fleet equipage planning for Mode S transponders I heard a lot about 5 and 3 mile separations being reduced to 3 and 1 which was supposedly a big driver in the roll from the DO-260 spec to DO-260A. This caused a lot of planning confusion if you operate globally. The FAA didn't acknowledge certification of anything but the version of the spec they wanted, making OPS SPEC approval to operate ADS-B in countries that accepted the DO-260 version nearly impossible, if not impossible to obtain.

And tonight I'm nursing an aircraft wiring mod run amuck. It's the mod to run the text data from the ACARS Communications Management Unit to the Flight Data Recorder. We refer to NEXTGEN as FANS now, and from what I see, aircraft that operate in Europe must be equipped with their version, if the FAAs version isn't installed by this year.

It's going to be interesting.
 
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I've used this a couple of times in Europe for the last several years it's called CPDLC - controller to pilot data link. Also use it on trans Atlantic and trans pacific flights as well. In Europe the controller can actually see what values you have set in the aircraft autopilot mode control panel.
 
When I read this it makes me laugh.

When I was doing ADS-B fleet equipage planning for Mode S transponders I heard a lot about 5 and 3 mile separations being reduced to 3 and 1 which was supposedly a big driver in the roll from the DO-260 spec to DO-260A. This caused a lot of planning confusion if you operate globally. The FAA didn't acknowledge certification of anything but the version of the spec they wanted, making OPS SPEC approval to operate ADS-B in countries that accepted the DO-260 version nearly impossible, if not impossible to obtain.

And tonight I'm nursing an aircraft wiring mod run amuck. It's the mod to run the text data from the ACARS Communications Management Unit to the Flight Data Recorder. We refer to NEXTGEN as FANS now, and from what I see, aircraft that operate in Europe must be equipped with their version, if the FAAs version isn't installed by this year.

It's going to be interesting.


The haven't even told us about reducing to one mile. I don't know how that'll play out with runway occupancy studies and wake, but it'll probably be the same result we have now.

It makes us laugh too. Its a gimmick, just like when they shut down MOAs during peak travel season and wonder why there are still delays.
 
NEXGEN which ADSB is a part of is multifaceted. In a slow ATC environment, text based communication will work. In the real ATC environment it won't. Speed of issuance being disregarded think about the last time you as a pilot heard a terrain or traffic alert. Tone of voice says everything and unless we break down how many !!!'s it takes to convey urgency.

On a similar note, if you're a regular and I'm busy I barely have to enunciate. "Seed wreck ABC Art ABC two zero zero." Type that? Proceed direct ABC. depart ABC heading two two zero. Or will the far AIM adapt so I can text ABC M8?

NEXGEN isn't fully here, its a great idea but it lags behind. We have it here in fusion. Three RADAR sets giving us an ultra accurate real time picture of where you are. Works well until planes start moving backwards when different sites disagree.

Aaaaand believe me the targets jump up to two miles erratically in one second. So much so that I've turned an MD80 base and 30 seconds later he's back where he was 60 seconds ago. Its like vectoring in a time machine.

After giving it additional thought, maybe after GPS position reports received by ground stations replace surveillance radar tracking it will eliminate the jitter you're seeing and make higher resolution tracking possible.
 
After giving it additional thought, maybe after GPS position reports received by ground stations replace surveillance radar tracking it will eliminate the jitter you're seeing and make higher resolution tracking possible.

I'm sure you're right. Oh well, 5 years, 3 months and 3 days to go till no more jitter! :mad2:
 
I personally believe better communications between the cockpit and ATC could improve safety. Missing routine radio messages seems common.

If loss of audio communications due to radio congestion or low signal strength is the problem to be solved, then the solution would be to change the underlying technology to something that can insure that audio gets through - the solution should not be to switch to text mode. Audio communications is well suited to piloting because you always get it regardless of your current mental or visual focus - text, not so much I think, because you have to visually scan for it.

Example: If 3 people all transmit at once, then using digital technology one can insure that they all hear each other without having to repeat themselves (the digital protocol hides all that work.) The receivers could be made to either emit the audio as if the 3 were all talking at the same time (which would be an improvement over the squeal that an analog radio might produce) or it could instead present each of the transmissions sequentially to the listener. Some transmissions will be heard a few seconds later than otherwise, but this would still be a big improvement over the analog case where some considerable time must elapse before the sender concludes the transmission didn't make it.

Other things are possible:

  • Automatic acknowledgement of reception of a transmission by the intended receiver(s). Such acks could be conveyed to the sender by visual or audio means.
  • Automatic addition of the sender's call sign, to be presented in whatever form the receiver prefers.
  • With some added button pressing: automatic prepending of the intended receiver(s) e.g. unicast to ATC or broadcast to local traffic. The destination information could be digitally encoded, allowing the receiver (if the person so desires) to automatically silence any transmissions not broadcast or unicast to them.
  • Automated encryption and authentication, where or if needed.
Audio communication using digital technologies are now well understood and in use today. But I don't expect aviation to shift from analog to digital within my lifetime. :( They'd regulate it to fiscal oblivion if it was pushed at all.
 
Jim Logajan said:
Audio communication using digital technologies are now well understood and in use today. But I don't expect aviation to shift from analog to digital within my lifetime. :( They'd regulate it to fiscal oblivion if it was pushed at all.

After WWII some movement was made to switch the VHF voice band from AM to FM. AM was chosen to remain because of the squeal when someone "steps" on someone else. VHF AM is now very deeply embedded in the system throughout the world.
 
I see it being extremely expensive as both ATC and the planes have to have the proper equipment.
Not really.

Just use Morse code. You have to learn it as a private pilot to properly identify VORs and the like, eh? And if, for some reason, you can't copy or send Morse at any reasonable speed, you can get Morse decoders to convert to/from text. But once you learn it, then it will be faster and easier - just like the codes in METARs and TAFs that everyone likes so much. Plus, it solves a lot of problems like "scratchy" radios, similar tail numbers, "foreign" accents, etc. No more "fife" or "niner" or ICO phonetic alphabet nonsense. Just clear, digital, no nonsense Morse.
 
A lot of you guys seem to be hung up on communications. Most of what ATC sends us is information. When information is digitized, accurate transfer information is very fast. In the system of the future, it's not so much the pilot that needs the information, but the aircraft's navigation system, so the information goes directly to the nav system. The pilot merely needs to monitor the new information.

Most people can read faster than people can speak and in the case of waypoint navigation, most people can comprehend the information much faster by seeing it depicted by colored lines on a moving map GPS display than they can by writing down what they hear, finding the waypoints on a map and then visualizing the route. Then there is the task of entering the route into the GPS nav...
 
Not really.

Just use Morse code. You have to learn it as a private pilot to properly identify VORs and the like, eh? And if, for some reason, you can't copy or send Morse at any reasonable speed, you can get Morse decoders to convert to/from text. But once you learn it, then it will be faster and easier - just like the codes in METARs and TAFs that everyone likes so much. Plus, it solves a lot of problems like "scratchy" radios, similar tail numbers, "foreign" accents, etc. No more "fife" or "niner" or ICO phonetic alphabet nonsense. Just clear, digital, no nonsense Morse.


You've seen my post that my Private DPE had a hangup on tune AND identify and almost typed up a pink slip until I asked "Why?" In his typewriter (yes, that long ago) and when he found out I knew Morse, he had to improvise a test on the spot in his office. I passed. He reached for the white paper. ;)

That said, aviation Morse is way to frigging slow. It's annoying. :) Farnsworth figured out a long time ago that characters should be sent faster with greater spacing to slow to a particular word-per-minute rate if you want to learn it as a language and not be converting dots and dashes in your head. You want to hear whole characters or even whole words as a continuous sound.

Slow Morse sounds like the idiots that saaaayyyy thiiiiingsss reaaaaallly sloooooowly tooooo deaaaaf peeeeeopple or non-native language speakers, to people who know Morse. :)
 
You've seen my post that my Private DPE had a hangup on tune AND identify and almost typed up a pink slip until I asked "Why?" In his typewriter (yes, that long ago) and when he found out I knew Morse, he had to improvise a test on the spot in his office. I passed. He reached for the white paper. ;)

That said, aviation Morse is way to frigging slow. It's annoying. :) Farnsworth figured out a long time ago that characters should be sent faster with greater spacing to slow to a particular word-per-minute rate if you want to learn it as a language and not be converting dots and dashes in your head. You want to hear whole characters or even whole words as a continuous sound.

Slow Morse sounds like the idiots that saaaayyyy thiiiiingsss reaaaaallly sloooooowly tooooo deaaaaf peeeeeopple or non-native language speakers, to people who know Morse. :)

I ran for a gentleman named Don Gompertz, if you're into HAM you may have heard of him. We had a HAM rig on this boat that was quite impressive. It also had a morse decoder that typed out on a CRT that he invented. We were in the salon talking one day, his back was to the set and I could see the decoder over his shoulder. Suddenly Morse comes smoking in sounding like a dial up modem handshake, I can't sort the dots from the dashes. I said,"It's a good thing you have that decoder, no one could read at that speed." On that he started speaking it ahead of the decoder.:eek: I told him, "Don, for all you've invented and all the money you've made, what you just did impressed me more than all that combined."
 
The main basis to it is fuel savings. That is what is going on at the airline level. The computer is figuring out descent profiles to keep everybody up high until the last moment then doing a power off descent all the way to the threshold without leveling off anywhere. They've been working it a while on the Transpacs at SFO with great results on fuel savings and an added bonus of less noise. It's kind of neat, the ground uploads the profile direct to the FMS is my understanding of it.

They tried that here and a certain airline lost so much money that we stopped doing it... OPDs make sense on paper, but they don't work with large amounts of traffic volume in a terminal environment.
 
They tried that here and a certain airline lost so much money that we stopped doing it... OPDs make sense on paper, but they don't work with large amounts of traffic volume in a terminal environment.

Where is here??:confused:
 
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