I haven’t written anything since June because I finally went over the top and became totally disgusted with the current state of our political affairs.  At precisely the time when reason and deliberative thought are most sorely needed, it is being intentionally undermined!  I don’t know about everyone else, but I deserve better from my government. And so does aviation!

How will this appalling new political reality impact NextGen?  Well, given the recent “serious debates” over whether or not the United States of American should pay its outstanding bills, or whether or not the government should provide education grants so our kids can afford college, or whether or not the government should subsidize winter heating oil for poor and the elderly, I’d think that the probability of funding for aviation research looks pretty low.  In this political environment how can anyone defend spending billions of tax dollars for research and development to make air travel more efficient for a relatively small and prosperous segment of the population?     

So exactly what is the defensive strategy for preserving aviation research and development? You’d think that it might be to create an army of defenders armed with solid information, rigorous analysis, and rational arguments to overwhelm the mindless political agenda.  You’d think!!  But so far the quiet has been deafening. Where is that NextGen soaring rhetoric and marketing genius when it’s needed? 

How about just some information so that our aviation army can have some ammunition before going off to do battle?  And what better information opportunity can there be but for FAA to utilize the grand stage of the 56^th ATCA Annual Conference and Exposition on October 3-5, 2011 to provide industry with the informational tools it needs to defend itself.  What we (industry) need is: (1) an updated vision of where NextGen is going beyond the current near-term focus on enhanced CNS capabilities, (2) information on the documented incremental benefits NextGen has achieved since 2003, (3) sound analytical proof that the actual “transformative” NextGen is still a viable goal, and (4) the status of the research into those genuinely transformational ATC technologies.   

Speaking for myself, there are certain things I need to know before I’d be willing to enlist in our army.  Hopefully at least one of the ATCA panel sessions will address at least one of these questions:

Question 1:   “There is no doubt that enhanced communications, navigation, and surveillance capabilities will provide operational benefits to individual users/operators in terms of enhanced planning and coordination, logistics, maintainability, reliability, etc., and even safety. However, they remain ATC enabling technologies that, alone or collectively, cannot provide systemic tactical ATC operational benefits.  An analogous transportation situation is the nearly ubiquitous presence of GPS navigation systems in almost every vehicle on the highway.  To what degree has that technology influx enhanced the efficiency of the highway system?  While my GPS unit is fantastically helpful to me, without some system wide planning and execution function that actually tells me how to change my route for the good of the whole; I’d have to answer, “Not much!  I still get caught in traffic delays”.  Similarly, NextGen is currently focused on the collection and distribution of aviation related “data” without much attention to developing any technological capability for tactical or strategic planning or control.  Please tell me I'm wrong.  I’d like someone on the panels to please address the status of research related to technological capabilities that will serve as the aviation tactical planning and execution functions.  Without these critical functions that are essential for changing the very nature of the ATC process, the claim for “transformation” seems to be inappropriate at best.  If the official response to the question is that developing such hugely difficult functions is unrealistic, impossible, or impolitic; then perhaps we have wrong people in charge of NextGen.

Question 2:   One of the ATCA panels is charged with addressing the requirement for workforce cultural changes in a NextGen environment.  Why? The six Transformational Programs and the seven solution sets are all focused on CNS enhancements and massive data collection and distribution capabilities, with nothing oriented towards applying advanced technologies to transform the actual ATC process.  The question is: “Except for expanded “collaboration”, how will the NextGen operational environment be any different from today’s environment?  Can the panel, or anyone else, describe the anticipated NextGen ATC operational environment, at a workforce role/culture level, with any certainty beyond the extremely vague speculation offered in the original NextGen concept?”

Question 3:  While FAA seems to have an abundance of resources available to simulate, analyze, and evaluate changes to the ATC system, those studies are usually focused on airspace changes, traffic routing changes, and other very pragmatic near-term approaches to enhancing system efficiency.  While that is a good thing, there is no evidence that those same resources are being applied to simulating and analyzing long-term NextGen concepts except for those that are mere extensions or variations on the current controller-centric ATC process.  I’m certainly no technologist, but I’ll bet there is any number of highly sophisticated ATC compatible technologies out there that could, in time, change (transform?) the very nature of air traffic control.  My questions are: "To what degree can the existing simulation capabilities simulate an ATC environment that is not controller-centric?" and "To what degree is FAA willing to let go of the conceptual reins and allow industry to begin to explore the operational viability of alternative tactical ATC concepts and technologies?"  Isn’t that why DARPA is a NextGen partner?

Naturally I don’t expect to have any of these broader questions addressed by any of the people on any of the panels.  But if someone doesn’t give the right answers to the right people right now, don’t be surprised if they receive an invitation to a Tea Party right soon.  If we as a nation fail to take the lead on developing and deploying an advanced ATC system and chose to simply continue to manage a routine technological evolution, then perhaps extraordinary funding for NextGen is not justified and that whole ATC transformation business can simply be left to the Europeans, or perhaps someday the Chinese.

First I’d like to correct my last my last Best Equipped, Best Served (BEBS) blog.   It was inaccurate to say that BEBS is intended to incentivize compliance with the ADS-B (out) mandate.  It is really intended to incentivize equipage of all NextGen communication, navigation, and surveillance (CNS) technologies. The origin of BEBS came out of the RTCA Task Force 5 recommendation that FAA expedite aircraft equipage of NextGen technologies in order to maximize benefits and to  “establish a National Airspace System (NAS) where users who have aircraft with higher aircraft performance/capability levels get higher levels of service.” While this sounds like a perfectly reasonable and sound recommendation, I’d feel a lot better if someone tested the assumption that expediting equipage is necessary before charging off with guns blazing.   

In any event, the first step would to examine the collection of NextGen technologies to determine which: (1) provide the most synergy for the NextGen development, (2) are most likely to provide significant stand-alone benefits, (3) are least likely to provide significant stand-alone benefits, and (4) can contribute most through the expediting of increased equipage levels.  This initial assessment can help focus the BEBS effort and may possibly demonstrate that early aircraft equipage is not the driving issue that everyone has assumed it to be, especially since the corresponding NextGen automation infrastructure is barely under development yet.   A more natural assumption might be that the equipage percentage would rise non-linearly with the increase in actual realized operational enhancements and benefits provided by NextGen.

But back to the problem: how do you encourage (or incentivize) aircraft operators to buy expensive NextGen CNS technology? Why not start by assuming that it’s the same approach you’d take to get anyone to buy anything. For example, how does someone decide which new vehicle to buy? (an imperfect but sufficient analogy)  There are five (5) obvious considerations that go into any decision to make a significant investment in expensive technology. 

Consideration #1: Does the technology offer a genuine benefit that I cannot achieve without it?

 If I want to routinely drive in snow conditions or over off-road terrain, I need to buy 4-wheel drive technology or I won’t be able to do that very well or safely.  Likewise, if aircraft operators want to routinely fly above FL290 they’ll have to buy a new super-precise altimeter so they can enter the Reduced Vertical Separation airspace where precise altitude maintenance has been determined to be a requirement for ensuring safety.  If they want to fly into Class B airspace they’d better have a radio and a Mode C transponder because those, too, have been determined to be requirements for ensuring safety.  The point is that these operators will purchase the technology because it grants them access to operational and economic opportunities they wouldn’t have without it AND they accept the premise for the restrictions as being valid, fair, and reasonable. 

Conversely, restrictions that can be interpreted as capricious and arbitrary are quite another matter.  During the 1990s, motorcycles were prohibited from using the 17 mile PUBLIC road along the perimeter of the Monterey Peninsula in California (think Pebble Beach) because the local community found them “annoying”.  Also during the ‘90s, motorcycles were not permitted on the HOV lanes in Virginia because; according to some absurdly infantile (I read it!) “analysis” by the VA DMV, they posed a “safety hazard”.  The arrogance and condescension of those government policies infuriated the motorcycle community.  By the same token, I’d fully expect arbitrary BEBS restrictions to result in the same, or probably far greater, outrage from the aviation user community.  It is crucial that any limitations to access of public airspace based upon the technology aboard the aircraft absolutely MUST be seen by the aircraft operators as being valid, fair and reasonable. Without that, BEBS restrictions are more likely to incentivize litigation than equipage.

Consideration 2: How valuable are the benefits to me?

If I live in Florida, how badly do I need snow capable 4-wheel drive technology?  Similarly, what is an aircraft operator’s justification to equip with ADS-B (out)?  Aircraft operators who currently operate largely outside of radar coverage will gain significant benefits through “radar” enroute and terminal services and will be eager to equip without any additional incentive.  But for the majority of users, ADS-B (out) offers almost no benefits despite the very dubious and unproven claim that controllers will be able to use airspace more efficiently simply because of faster track update rates and more precise position data.  (This could be a topic for a subsequent blog)  Any attempt to incentivize voluntary ADS-B (out) equipage would probably be an effort in futility, hence the need for a mandate.

GPS, on the other hand, provides significant benefits to users if for no the reason than for the simplicity of navigation if offers.  I haven’t used a AAA map to navigate my car since I bought my GPS navigation system, so I’d imagine that pilots would find an aviation GPS system even more desirable. Even users with operations into isolated airport can get GPS benefits through the development of Localizer Approaches with Vertical Guidance charts and procedures.  GPS offers so much in potential benefits to individual aircraft that achieving high equipage levels will probably not require any additional incentives. 

On the other hand, the Data Comm technology as currently described seems to focus on transmitting non-tactical flight plan clearances, routing changes, and other data to the cockpit.  While these data transmitting capabilities would certainly provide operational efficiencies beneficial to the ATC system, the value to the users would consist primarily of receiving non-tactical data plus second order ATC efficiency benefits that may or may not be realized.  Probably not until the Data Comm technologies begin providing direct tactical benefits to the user, such as real-time tactical information or ATC clearances within a highly automated ATC function, will the cost of equipping a fleet of aircraft make much economic sense.  The incentive trigger here would be to be able to access tactical information that will give them an edge over their non-equipped competitors.

Consideration 3: Will the system allow me to utilize the beneficial technologies?

I may be able to buy a car with 600 horsepower engine technology, but I live in the Washington metro area and 550 of those horses would never leave the barn.  Why would I buy it?  While the raw potential benefits of GPS are enormous, additional published GPS routings and approach plates either replicate existing routings and approaches plates or they compete for the same airspace and controller attention.  In congested, highly complex airspace that is operating at or near the human capacity of controllers, the LAST thing the system can accommodate is additional routings and/or transition and approach procedures.   In these cases where the new technology cannot be safely accommodated, it is the system itself that will impede the level of equipage because the human controllers are unable to accommodate “special” procedures.   Publishing hundreds or thousands of GPS routings and approaches isn’t the same as using them operationally since their use must be approved by the human air traffic controller sitting in front of a radar scope.   An incentive might be a requirement that the new GPS charts must be developed in concert with their associated ATC facilities so that their application is complementary to, or at least compatible with, existing ATC procedures; increasing the likelihood of their being approved by ATC.     

Consideration 4: Will the system be changed to allow me to fully utilize the NextGen technology? 

For my 600 horsepower car analogy, is there an American Autobahn in the works? My new car’s engine is only an enabling technology and people have to remember that communications, navigation, and surveillance are also ENABLING TECHNOLOGIES, they are rarely the solution! NextGen often references the Collaborative Decision Making (CDM) development as a model for NextGen, but consider that even if CDM had perfect CNS capabilities, without the Flight Schedule Monitor (FSM) software capabilities that dispatchers and flow managers used to actually perform the CDM planning functions there would have been no CDM; there would have been NOTHING! 

Like CDM, NextGen must develop a new ATC automation counterpart to FSM that will change the fundamental ATC process to accommodate and maximize the utility of the enabling technologies.  Without that FSM equivalent, NextGen will also have NOTHING except for short term technical enhancements and next-step development, often referred to as system “modernization” or “replacement” programs! 

While the NextGen 2025 vision implies a completely new ATC automation concept, I see very little ongoing or planned efforts to actually develop one.  I don’t even detect an acknowledgement that such a critical infrastructure component is even required for NextGen.  Without that clear acknowledgement, why would any operator have an interest in investing dwindling capital for new technologies that will clearly operate in a human limited ATC environment similar to the current system?  An incentive to equip aircraft might be for FAA to show some interest in developing the actual NextGen automation capabilities instead of seemingly doing nothing tangible beyond publishing GPS routings and approach plates.  

Consideration 5: Is there proof that this technology has actually produced any meaningful benefits?  

As a car driver I can see the benefits of new car technology every day.  When my model of motorcycle went from a five-speed to a six-speed transmission, I couldn’t buy a new one fast enough!  Everyone will stipulate that the narrow spectrum of GOMEX, Alaska, and other users with isolated operations will gain significant benefit from both ADS-B (out) and GPS RNAV.  However to reach any mass equipage level, all the other operators must also believe that their investments are going to return significant operational benefits.  FAA should go beyond just announcing the number of GPS routes published or providing anecdotes of speculated GPS applications and actually document, quantify, and celebrate the actual operational benefits that have resulted from publishing a billion new GPS routings and approach plates.   They should document, quantify, and celebrate the actual enhancements to procedures and the resulting benefits brought about by the deployment of ADS-B at Philadelphia and Louisville.  FAA should take every opportunity to document, quantify, and celebrate every significant operational improvement brought about by NextGen technologies.  (Of course, for credibility purposes, it would be critical that such documentation be provided by a neutral, objective organization completely independent of FAA and NextGen.)    The incentive would come from the increased confidence aircraft operators would have that NextGen is real!

So What’s the Plan?

The NextGen technology that can provide the most operational benefits to users with the least amount of developmental risk and dependence on other NextGen developments is ADS-B (in).  Simply enabling an aircraft to see other ADS-B aircraft is a monumental enhancement to aviation safety and would be a technology that aircraft operators of all sizes and types would rush to install.  Therefore, my first “order of business” would be to stop all activity aimed at incentivizing ADS-B (out) and place a top priority on defining the initial specifications for ADS-B (in), with minimal functionality (e.g., traffic display) but with only “hooks” to future capabilities. A specific condition would be to not saturate the specification with requirements that support every envisioned NextGen function, and especially not something like supporting the Self Separation Airspace (SSA) concept, because that would make it a never ending task . (NOTE:  the Self Separation Airspace concept would require FAA to abdicate its responsibility for aircraft separation assurance and place that responsibility on the pilots in the cockpit, and it “ain’t never, ever gonna happen.”   In fact, this idea is so patently absurd that it should be immediately deleted from the NextGen 2025 vision and never spoken of again.  Who dreams this stuff up?)

At the same time I’d pull back on publishing another thousand GPS routings and approach plates to focus agency effort and re-direct funding towards defining, designing, and developing the fundamental operational NextGen components and functional capabilities of the new tactical ATC automation functions (software, not hardware).  I’d focus on developing and researching human factors (skinware), working models, simulations, and specific analyses instead of spending endless time and funds on excessive esoteric planning exercises (manure-ware). 

I’d also expand the research on the digital air-ground tactical communications capabilities that will be required if a highly automated NextGen ATC system is ever going to be operationally deployable.  Hopefully these combined efforts will be seen as a good faith effort by FAA and convince aircraft operators that FAA is serious about NextGen and will be there to develop and support the technology that will provide them with significant operational benefits.  If aircraft operators gain some confidence in FAA’s commitment to NextGen, the likelihood of increased equipage levels will rise dramatically without the need to “incentivize” anyone. 

It appears to me at least, that the claim that user equipage is critical to NextGen success may be a bit of an overstatement since it’s not clear how even immediate full equipage would positively impact development.  Hoefully this does not reflect a belief that NextGen is primarily a communinations, navigation, and surveillance "transformation".  In fact, someone far more cynical than I might even suspect that such a statement may actually be a preemptive effort to divert blame to aircraft operators if NextGen should fail.  Don’t know; just sayin’.

FAA should LEAD by example from in-front (show progress) , not whip from behind (issue mandates). The bottom line is that if you have the right product at the right time at the right price, you shouldn’t have to force (oops, “incentivize”) anyone to buy it.

I haven’t heard much about it lately but given the importance FAA has placed on users equipping with ADS-B technology, I have to assume that the “Best Equipped, Best Served” (BEBS) strategy is still under active consideration.  As I understand the situation, the driving force behind the BEBS policy is the absolute conviction within the aviation technical community that the capability for an aircraft to transmit its own precise GPS based position to the ATC system will immediately produce significant increases in ATC efficiencies and is fundamental to achieving the NextGen vision and promise.   Therefore, the reasoning goes, it’s essential that the entire inventory of IFR capable aircraft be equipped with ADS-B as quickly as possible or NextGen will fail, hence the FAA mandate requiring aircraft to have ADS-B (out) to operate in all airspace currently requiring a transponder by CY 2020.  The BEBS policy is simply an attempt to “incentivize” compliance with the mandate.  It should be noted that most people with a thorough understanding of actual ATC operations question the basic premise of the argument. (NOTE:  Let me just say that, in my opinion, the actual fundamental enabling technology critical to achieving NextGen capabilities is neither navigation nor surveillance but rather advanced communications technologies that go far beyond the simple transfer of data to the real-time delivery of tactical information and ATC clearances. But that’s a topic for a later blog)

Let’s get back to Best Equipped, Best Served.  According to Dr. Phil, people don’t do anything unless they perceive some sort of benefit in doing it.  Operators with flight operations over the Gulf of Mexico, Alaska, or other locations that do not have existing radar coverage will eagerly equip with ADS-B so they can gain the economic benefits of ATC radar procedures.  That’s not the problem.  The problem is with operators having flight operations in the remaining 99% of the airspace that has full radar coverage.  Their ADS-B benefits are negligible at best, so why equip? The argument that they will receive operational benefits in later stages of NextGen is not very convincing; besides, they’ve been burned by that line before.  How do you encourage these operators to equip? Best Equipped, Best Served?

The FAA BEBS strategy is intended to create artificial ADS-B benefits in order to encourage users to equip. The BEBS concept, as I understand it, is that aircraft equipped with ADS-B will receive the most efficient routings through the most efficient airspace to land on the most efficient runways with the least ATC delay, while non-equipped aircraft will be forced to bear the economic burden of operating with a reduced level of service.  If FAA was in the business of selling ADS-B systems, withholding ATC benefits, features, and capabilities would be a great marketing approach, especially as the monopoly ATC service provider.  I think I’ve seen movies where certain organizations used that kind of “convincing” to sell protection services to small businesses in the garment district.  Or, it could be that old “run government like a business” stuff again.  Microsoft would love to do something like that except for those damn government people at the U.S. Department of Justice.

It should also be noted that BEBS policy is addressing airspace usage and runway assignments, with ADS-B equipage being completely irrelevant to those operations. Therefore, under BEBS, non ADS-B equipped aircraft operators would be penalized for failing to equip their aircraft with irrelevant equipment. What’s wrong with that picture?

Because FAA is the monopoly ATC service provider with the power of The Mandate, let’s assume that BEBS becomes the policy of the land.  Now imagine air traffic controllers working actual traffic.  Controllers consider the traffic under their control and, based upon the aircraft types, arrival/departure fixes, runway and taxiway limitations, standard procedures, parking areas, and other factors, run the traffic in a way that gets all the aircraft on their way or on the ground as expeditiously as possible.  Under BEBS, an additional consideration would be if the aircraft is or is not ADS-B equipped because that will define the quality of service to be provided. This additional factor would create a whole new family of operational requirements and restrictions for the controllers, be a huge increase in controller mental workload, and probably create an operationally chaotic control environment sufficient to significantly decrease terminal capacity and increase delays. Not a good unintended consequence.

For the BEBS policy to be effective, it would also have to prohibit controllers from giving any of the reserved “best” service to non-ADS-B equipped aircraft operators under any circumstance because “free” benefits would undermine their incentive to equip. In that situation, one assumes that controllers would be expected to intentionally not use the full capacity of the airport and associated airspace (i.e., decrease capacity) to demonstrate to operators the economic cost of less efficient services as a simple matter of enforcing the BEBS “encouragement” objective.   Is this beginning to bother anyone yet?

 Finally, BEBS means that the U.S. government would deny non-felon U.S. citizens (and others) access to open public airspace without justification.  Or is there some justification?  Does ADS-B provide a significantly higher level of safety than radar?  To what degree?  Where was the rigorous analysis, documentation, and public debate of BEBS?  Or is the BEBS concept based completely on the undocumented and unsubstantiated speculation that ADS-B is fundamental to achieving unspecified NextGen operational capabilities?  I’m certainly no constitutional lawyer but it seems to me that depriving citizens of their liberty to utilize public airspace without cause or due process of law just might be a violation of the 5^th Amendment to the U.S. Constitution.  At the very least it seems like a Federal abuse of power.  Don’t know, just sayin’.

These are just the most egregious issues surrounding BEBS.  My first question is who brought this idea up in the first place?  More importantly, who was the first person to approve it as an official government strategy? How did it get to be an officially endorsed strategy of the FAA Administrator? Did anyone run the idea past General Counsel to confirm its legality and constitutionality?  Did anyone run it by the Congressional Affairs office since it clearly has political “Big Government”, “Anti-business”, “Freedom”, “Liberty”, “Government Intrusion”, etc. implications?  Lastly, did anyone consider the operational issues associated with the execution of the policy; the ones that the old independent Air Traffic Service would have raised to keep this terribly flawed policy from ever surviving the first discussion?  Apparently  not.

 I attended the Air Traffic Control Association (ATCA) Technical Symposium during the week of May 16^th at Atlantic City. The NextGen program was allocated one session titled “Meeting NextGen Challenges” but I would love to see ATCA sponsor a technical symposium solely dedicated to discussing the NextGen concept, the technical issues, and the development status of all the program components. NextGen is that magical "transformational" program that no one seems to be able to explain and I'd like to know more about it. I want to know more than simply the number of new GPS/RNP routes and approaches that have been published or the status of ongoing profile descent demonstrations. There HAS to be more than that going on! 

 For example, a NextGen cornerstone capability for 2025, in fact the foundational capability, is Trajectory Based Operations (TBO) which is the concept whereby individual aircraft will be able to “negotiate” a 4D trajectory with the ATC system to fly their optimal routings as well as their optimal climb and descent profiles. This genuinely transformational concept creates a "free flight" traffic flow environment that, at least conceptually, provides significant operational efficiency enhancements for aircraft operators. What is the status of TBO? Now that we’re 8 years into the NextGen effort, it should be relatively well defined by now.  

At the same time, two cornerstones of terminal operations are the GPS navigation based Required Time of Arrival (RTA) and Optimal Profile Descents (OPD) concepts whereby aircraft are assigned and expected to execute extremely precise 4D arrival paths that will enable optimal metering and minimum spacing of aircraft as they cross the landing runway thresholds. In this environment controllers will somehow manage the upstream metering and merging process (although the operational details of how that will be done seem to remain undefined) to achieve the maximum capacity of the arrival runways.

While I’m not aware of any simulations or other analyses of how the TBO may work, there has been an avalanche of simulations for the RTA and OPD that show almost no scattering of aircraft tracks between the arrival fix and the runway threshold. The analytical conclusion is that the aircraft get their optimal routing and descent profile without unnecessary distance being added through inefficient vectoring, thereby saving time, fuel, emissions, and narrowing the noise footprint to only those people living directly under that optimal flight track

The symposium panel session on NextGen did have a status update on this NextGen concept, followed by a second panelist who gently raised a significant NextGen challenge that must be considered before much more effort goes into this GPS navigation application. His name was Mel Davis. He was an air traffic controller at Los Angeles tower for ten years and then a radar controller at the Southern California TRACON for another ten years. He is now the National NextGen Representative for the National Air Traffic Controllers Association (NATCA).

Mr. Davis’s comments were specifically addressing time-based (i.e., metering) vs. distance-based (vectoring) traffic management and separation assurance. His point was that humans think spatially while computers think temporally and that managing traffic based upon time is not consistent with natural human mental processing. Mr. Davis is correct, which means that while time based metering may be an easier technical aproach and programming task for developers of automation systems, forcing controllers to make the mental conversion from time to distance in order to comply with metering time requirements significantly adds to controller mental workload .

Mr. Davis also showed a slide with two pictures on it. On the right side of the slide was a graphic showing the disciplined and orderly flow of the simulated aircraft tracks of multiple aircraft flying precise arrival paths while complying with assigned runway threshold crossing times. On the left side was a graphic showing the undisciplined and disorderly flow of actual aircraft tracks of multiple aircraft being vectored to intercept the final approach course. Common wisdom within the NextGen technical community is that the precise tracking is, by definition, more efficient and a significant enhancement to terminal operations.

Mr. Davis went on to make the comment that there was a “beauty” in the graphic on the LEFT (the one with the vectored aircraft). There was a repressed chuckle in the audience, with most folks assuming he had misspoken. Mr. Davis then continued, explaining that the vectoring allowed controllers to factor in the variable characteristics of the individual aircraft types and their crews and that vectoring is really the best way to maintain pressure on the runway, with separation (and therefore capacity) being limited largely by the landing aircraft’s runway occupancy time. It may have been my own cynical view but I would swear that almost everyone in the audience was stunned and wanted to shout out: “He’s not an electronics engineer, he’s not a computer scientist or a technical analyst, he’s not even a pilot; he’s just an air traffic controller, and a UNION REP at that – what could he possibly know about the SCIENCE of air traffic control”

However, Mr. Davis is absolutely correct! Not every aircraft is a B737-800. Every aircraft type has its own operating characteristics. B-747s are handled differently than regional jets, which are handled differently than turboprops, which are handled differently than twin-engine props, which are handled differently than single engine props. And an IFR Cessna 172 can block a final approach course for what feels like hours. To require an aircraft to operate at a faster or slower speed than its inherent optimal simply to maintain a precise arrival path to achieve the optiomal system metering requirement obviously forces the aircraft to operate sub-optimally. 

Vectoring allows fast aircraft to SAFELY pass slower aircraft; vectoring enables delaying vectors to re-sequence the set of arrival aircraft into a more efficient landing order and allows controllers to squeeze more aircraft closer together to keep maximum pressure on the runway. Vectoring also allows controllers to accommodate VFR arrivals requesting sequencing service or a practice IFR approach, it accommodates tower enroute arrivals, and it accommodates that occasional missed approach or go-around. Can a metering program perform ANY of those capabilities? The NextGen arrival concept that many people seem to believe is almost ready for deployment isn’t even CLOSE to being operationally useful, let alone acceptable. To think otherwise and to think that simply assigning aircraft arrival metering and runway threshold crossing times while, at the same time, expecting terminal controllers to ensure both separation AND compliance with a precise trajectory is just . . . well, let’s say naïve.

Therefore, a key NextGen challenge to “meet” might be to figure out how to develop the NextGen technology such that it is at least operationally compatible with the way the human users of that technology function. It would be even better if the technology addressed the full scope of the controllers’ job and not just a single component part. It would be still better if the technology intended to enhance aircraft operator benefits also made the controllers’ job easier rather than harder. Simply changing the ATC handbook is not an effective approach to dealing with the human factors issues. It makes no sense to develop technology that increases operational risk and/or workload for controllers, which then forces them to passively or aggressively resist the threat to their own well-being, and then complain that the controllers are anti-technology. No, they’re just anti—poorly designed technology!