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KSN770 - opinions?

Purist maybe, but at least I don't have to go around just because the AP decided not to capture the GS 8-)

Well that's also true, but my view is that

  • all installed equipment should function, and should function seamlessly, and

  • the autopilot is an absolutely vital cockpit workload reduction tool, which should be used at every opportunity during "real" flight

I do practice hand flying (I think most of us don't get enough hand flying practice in IMC) but I do it where nobody cares about my trajectory i.e. UK Class G, IMC, low level where icing is not an issue.

All my "Eurocontrol IFR" flying is carefully managed to be VMC on top, away from any hazardous wx. Hand flying up there is just stuff you could teach a monkey to do - so long as you somehow make the oxygen cannula stay up its nose.

I would suggest that is how everybody should fly that sort of IFR (radar controlled flight in CAS, etc). We (private IFR GA) have a responsibility to appear as professional and possible, to not upset ATCOs who will then slag off GA at their next teabreak, and that kind of stuff works its way up the system, to people who have no concept of GA. Already, many European airports are "managed" by people who have no concept of sub-bizjet GA and one would not want to feed that prejudice any more. We already have people in the ATC world who are scared of the CBM IR and the EIR and are worried about hordes of Cessna 150s flying in "their" airspace. This is not an unfounded concern; I've been to presentations by e.g. the UK ATC (NATS) where such crazy views were aired. It was seriously proposed for example to ban single pilot jets (UK ATC) and to ban all jet flight without an ATPL (German ATC). Then some old boy with the proper grey hair asked what they want to do about the Citation 1-4 fleet... there was silence as they obviously didn't know these are SP certified. Fortunately these views tend to not go far because - at a certain level - cooler heads (who fly or used to fly real planes) prevail, but if you run this scenario for years, it isn't going to make life for IFR GA easier. We already face PRNAV-enroute which will stick on another 10k-20k upgrade cost, just so you can fly as you always used to before, and which will wipe out most of the sub-€100k IFR tourer scene which can currently run on just BRNAV kit.

With the exception of adding the ARINC 429 inputs to the KFC225, there should be no extra work required on the autopilot side of the interconnect

What does the KFC225 do with the ARINC429 signal?

AFAIK the only context is roll steering in the GPS-NAV enroute or GPS/RNAV approach scenario i.e. lateral flight only. LPV approaches are flown using the analog signals for both lateral and vertical deviation - is that right?

Administrator
Shoreham EGKA, United Kingdom

Well from the moment you go MFD/PFD it's all ARINC429,...My bird has a Century 41 It's one of the first generation digital A/P's.LPV is known in europe as APV/SBAS you have vertical guidance also with baro but that is called APV/BARO

The status in Europe can be checked here:

Can anyone get that map of GPS approaches to work? I cannot select the various types of approaches. All the buttons appear to be dead. I have tried in both FF and IE.

Administrator
Shoreham EGKA, United Kingdom

the autopilot is an absolutely vital cockpit workload reduction tool, which should be used at every opportunity during "real" flight

True; I wouldn't want to fly longer legs without an AP.

But in my opinion you get pretty much all of the workload reducing benefits with an AP that can only hold a heading and an altitude, and this is what fully analog APs do quite well. More complex modes can be counterproductive.

Since my club purchased C172s with G1000 and the Garmin AP, we've had several people departing from their assigned level by more than 500ft. Granted, VFR, but still in controlled airspace (CTR of the nearby military airfield). It always happens like this: it starts with the AP and the pilot disagreeing about what mode the AP should be in, then in the heat of the action the pilot tries to oversteer the AP by brute force, which in turn causes the AP to increase the opposite force, i.e. a classical trim runaway.

Another classic is the AP for some reason not wanting to capture the GS. Seems to happen quite often when I watch with King AP's... This usually causes a massive increase in workload (first trying to debug the AP, then start to think about how handflying this approach could work) compared to when you actually briefed a hand flown approach and are fully ready to do it.

LSZK, Switzerland

Did you register? About the KLN90B ,...I have my doubts that all GPS RNAV app for Europe are in the Data Base... For en-route it's still Ok I think....Anyone want to dump a GNS 430/530 for a good price...?

EBST

What does the KFC225 do with the ARINC429 signal?

AFAIK the only context is roll steering in the GPS-NAV enroute or GPS/RNAV approach scenario i.e. lateral flight only. LPV approaches are flown using the analog signals for both lateral and vertical deviation - is that right?

The KFC225 uses the ARINC 429 roll steering instead of CDI guidance anytime the GPS is providing a valid roll steering label, GPS mode is selected, and Nav mode is selected on the autopilot.

If one is flying a full procedure using the GPS for lateral navigation including any required turns, procedure turns, holds, and DME arcs (not including an RF leg) up to the intermediate leg that terminates at the FAF, then the ARINC 429 may be used to guide the autopilot. Once the waypoint that defines the beginning of the intermediate leg that ends at the FAF is passed, the GNS/GTN will display a message that expects the pilot to activate the autopilot outputs followed by selecting APR on the autopilot. At this point, the lateral is controlled by the CDI deflections and the GS is eventually intercepted and tracked.

KUZA

@ Peter - as Vref says you have to register first

The PBN Approach map is accessible to all users of the EUROCONTROL extranet via the Onesky Online services. (username and password required)

EDxx, Germany

Since my club purchased C172s with G1000 and the Garmin AP, we've had several people departing from their assigned level by more than 500ft. Granted, VFR, but still in controlled airspace (CTR of the nearby military airfield). It always happens like this: it starts with the AP and the pilot disagreeing about what mode the AP should be in, then in the heat of the action the pilot tries to oversteer the AP by brute force, which in turn causes the AP to increase the opposite force, i.e. a classical trim runaway.

Isn't that just a combination of poor type specific training, and perhaps allowing people to fly the plane who have difficulty understanding the autoflight systems?

I don't think anybody would suggest that absolutely everybody can get a 737-800 type rating just by throwing endless money at it, yet modern GA avionics use a lot of the same principles, and there is no type rating. You can fly such a plane with just a bit of diff training, done on a nice VFR day, and without any significant systems training. I've read countless postings (not here) by pilots who demand the right to fly a G1000 equipped plane without any such training, VFR only, map and stopwatch only. Then... somebody presses the AP button and one is in for a whole lot of fun

Another classic is the AP for some reason not wanting to capture the GS. Seems to happen quite often when I watch with King AP's... This usually causes a massive increase in workload (first trying to debug the AP, then start to think about how handflying this approach could work) compared to when you actually briefed a hand flown approach and are fully ready to do it.

I've never had that. Surely that is just duff equipment? Perhaps there is a signal loss in the system. I know somebody who cannot pick up the GS until 7D, and it will take a competent avionics shop to test the signal path for the correct levels.

you have to register first

I might try that, but if it just shows where GPS approaches are, there are plenty of other ways to find those.

It might also show airports with PRNAV SIDs/STARs but those airports just ignore them...

Administrator
Shoreham EGKA, United Kingdom

NCYankee - thanks for that great explanation. Does it apply to both the GNS and GTN boxes?

Administrator
Shoreham EGKA, United Kingdom

Peter,

My understanding is that both the GNS and GTN boxes require this setup with the KFC225.

With respect to the G1000 GFC700 implementation, they do a better job on following a LPV lateral path than they do on an ILS, because the CDI deflections are still used to control the ILS lateral verses roll steering for the LPV lateral path. The ILS is subject to S turns when crosswind component changes as the aircraft descends whereas the LPV lateral path is wind corrected all the way to near the GPIP (glidepath intercept point) on the runway.

KUZA
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