RNAV/RNP questions for atc1


#1

atc1,

Your advise and insight on this board has been invaluable…thus, I figured I’d turn to you w/the following:

- Most pilots/controllers/passengers poopoo the idea of automated UAVs and would prefer pilots "in the seat" to mitigate whatever situation the three may face while "working" together.  

With that said, I wanted to ask your opinion on the growth in popularity of RNAV/RNP. Although pilots love it (but hate to admit it takes us one step closer to being pushed out of the cockpit), how do controllers feel about the popularity of these nearly “automated” procedures? I mean, with the jet flying the RNP, tracon is pretty much relieved of the “chess game” that was once the norm around busy terminal areas…gone are the days of rapid fire vectoring and missed calls…now the jet does it all with very little controller/pilot influence and is capable of doing it from wheels up to touchdown…thoughts?

Cheers,
Jack


#2

Until atc1 gets a chance to respond let me throw this in:

RNAV/RNP refers to horizontal navigation and generally has to do with the onboard nav equipment being able to navigate point-to-point without reference to ground-based navaids. You might mean inclusion of VNAV(a part of RNP) for a descent profile as well. The top end of these systems can be programmed to control the autopilot and have it fly most of the journey. Also, some planes are capable of auto-landing, although a pilot sill has to hit the brakes and turn off the runway. But these are the very top end of the technology.

I don’t think a fancy autopilot is taking “us one step closer to being pushed out of the cockpit.” It might be one thing if there were only one airplane in the air at a given time, but as long as there is more than one (and there always is) there has to be someone to keep them from running into each other. The autopilot takes a load off the pilots, but it will never replace them. You can program a system to fly virtually the entire trip, but you can keep it from running into something that’s not in it’s database and it can’t decide the best course of action if the plan changes, i.e. weather enroute. They don’t take commands from ATC (with current technology).

The currently “popular” RNAV/RNP capability isn’t even widespread on low-end planes, but is gaining, and that would be a basic panel-mounted IFR GPS which is often, but not always, coupled to an autopilot for horizontal nav only. The most popular of this type of capability is the hand-held GPS which can only be (legally) used for VFR navigation and not to automatically control the plane. So it’s not replacing anyone.

People are nervous getting on an automated tram at the airport. They’re not about to get on a fully-automated airplane. :slight_smile:


#3

BTaylor,

Appreciate your comments. Keep in mind, for the purposes of our board, let’s use RNAV/RNP generically to incl. LNAV/VNAV, Baro-VNAV etc…also, let’s assume all levels of RNP being equally cosmic and avoid getting into the various nits of say RNP-0.3 vs RNP-0.5 etc or the various issues concerning whose airspace one is operating in (ref Eur vs USA)…

That said, would like to point out 2 things…

First, with a great FMS, flying “RNP/RNAV” will enable crews to realize flights where, from the moment the wheels are in the wells to the “0-0” approach, the jet does it all. And, as you point out, w/autoland all you really have to do is monitor the app and taxi to parking. And with the new technology the “Bus” is working on, you barely have to touch the brakes! With “brake to vacate” capability, the jet will “automatically and smoothly” apply the brakes based on the parking spot you’re assigned as early as pushback or as late as the IAF.

Second, I’d encourage you to rethink your notion that as long as there’s more than one airplane flying there’s a rqmt for a controller and pilot in the loop…Today, at this very moment perhaps :slight_smile:, there’s an acft flying, fully automated, from STTO-cruise-approach and fullstop with nary a “man in the loop.” What’s more, it’ll do it as a two ship if you really need it to…heck, even the latest air taxi proposals are boasting this sort of full automation :slight_smile:.

Granted, as you suggest, this sort of thing will not be widely available for sometime, imagine what the air traffic system will look like two decades from now…heck, there are still airplanes out there with Nav tables **AND **F/E positions in em! There may come a day where the “man in the loop” is truly there as just as another redundancy! (Insert Homer Simpson like shudder here…)

Cheers,

Jack


#4

Didn’t I say that? :slight_smile:

I agree that completely automatic flight is possible and some high-end airplanes can do it now. But it can never happen “with nary a man in the loop” unless EVERY aircraft is following the same coordination, some master computer somplace. Otherwise one will sooner or later run into another one that is controlled by a different method.

I’ll cite the “TFR” that’s required along the southern border to keep UAVs from running into other aircraft. You can’t have piloted and non-piloted aircraft in the same airspace. The only way you can get EVERY aircraft controlled by the same master system is to tell me, dbaker and everyone else that we can’t fly our Cessnas anymore. Ain’t gonna happen! As long as airplanes exist, there will be people who want to fly them by hand. If there are also fully automated airplanes flying around, they will have to kept apart. I think this will be the same in 2 decades or 20.

Aside from normal navigation and control issues, what happens when things don’t go as expected, a system malfunction or unexpected weather? While a computer could determine “if A happens then take action B” it will be a long time in the future before they will have true AI that could evaluate a complex problem and make a decision. I’m sure you have seen the famous video of an Airbus settling into the trees and crashing after a fly-by. Yes, that was from a switch in the wrong position induced by a pilot, but why couldn’t the plane’s computer figure that out before committing suicide?

I’ll trust a computer to wake me up in the morning, help me post this on the internet, or to control the fuel and ignition system in my car. But I’ll never trust a computer “with nary a man in the loop” to propel me through space at over 500 MPH. I don’t think anyone else will, either. Anyone who could has never used a PC running Windows!


#5

BTaylor,

Appreciate the give and take here…Even if it’s just us, I consider it a good discussion. Just a coupla points:

B: “…But it can never happen “with nary a man in the loop” unless EVERY aircraft is following the same coordination, some master computer somplace. Otherwise one will sooner or later run into another one that is controlled by a different method.”

J: I’ll grant you the fact that it’d be difficult but “never?” Nah…fully automated interactive AI already exists…Data linked acft with appropriate interrogators on board bring us to the realm of the possible…whether or not it’s practical remains to be seen. I will tell you that the larger threat to this concept is bandwidth…

B: I’ll cite the “TFR” that’s required along the southern border to keep UAVs from running into other aircraft. You can’t have piloted and non-piloted aircraft in the same airspace.

J: Not necessarily true. Keep in mind, for the most part, the a/c operating down south are not the same as what we’re discussing here nor do they use the same mission criteria. Again, for the most part, those a/c are flown by human operators and are fully taskable. They do not rely on an avionics suite capable of fully automated flight but instead a, “man in the loop” sitting in a trailer somewhere looking thru a camera with a limited view. Also, in being fully taskable, those a/c do not follow a “wired” flight plan thus, the deconflicted airspace they require turns into a “TFR” all their own.

B: The only way you can get EVERY aircraft controlled by the same master system is to tell me, dbaker and everyone else that we can’t fly our Cessnas anymore. Ain’t gonna happen!

J: I hear ya but, again, not nessarily true. A data linked a/c on a “wired” flight plan, operating w/ETCAS+, an RNP/RNAV,GATM suite, and advanced AI could enter the enroute structure and stay safe. Add in the appropriate altitude deconfliction and new RoW rules and this idea could become entirely possible. Practical for civil use? Who knows?

B: Aside from normal navigation and control issues, what happens when things don’t go as expected, a system malfunction or unexpected weather? While a computer could determine “if A happens then take action B” it will be a long time in the future before they will have true AI that could evaluate a complex problem and make a decision.

J: Not really bud…All of those “problems” can be reduced to mathematical equations. AI already solves system malf. in a snap w/triple redundancy in many advanced airliners…And think about the last time you had to divert or skirt around Wx…you analyzed the situation, you picked an alternate, stated your intentions, made a course correction, and landed as soon as practicable. A mere process. Something my cell phone is doing right now as it evaluates the best tower to use for crisp reception or what google does everytime you run a search.

B: I’m sure you have seen the famous video of an Airbus settling into the trees and crashing after a fly-by. Yes, that was from a switch in the wrong position induced by a pilot, but why couldn’t the plane’s computer figure that out before committing suicide?

J: It wasn’t programmed to to figure that out. Human pilots are innately programmed to avoid the ground yet we read about CFITs all the time.

B: I’ll trust a computer to wake me up in the morning, help me post this on the internet, or to control the fuel and ignition system in my car. But I’ll never trust a computer “with nary a man in the loop” to propel me through space at over 500 MPH. I don’t think anyone else will, either.

J: Shuttle crews do…every launch…500MPH+…All kidding asisde, I hear you…I’m not about to get giddy about riding in a pilotless tube but, that doesn’t mean we’ll never see the technology come to fruition…

Anyone who could has never used a PC running Windows!

J: Touche.

Cheers
Jack