Turn off WAAS/Egnos without going into maintenance

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   Is there any way in normal operational mode (not maintenance) to turn off EGNOS so that a 2D RNP approach can be flown at an airfield where LPV is available?
Europe skill tests require both 3D and 2D approaches. VOR approaches are rapidly going the way of the dodo bird and NDB are in many countries (almost) gone. Many airfields now have only ILS and RNP LPV approaches to choose from, which gives no possibility to do a 2D approach.

Garmin has a user setting to turn off EGNOS/WAAS which then reverts all RNP approaches to LNAV only. This would be useful for the IFD too, but I haven't so far found a way to do it.

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chflyer Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 24 Jan 2013 Location: LSZK Status: Offline Points: 1022	Post Options Post Reply Quote chflyer Report Post Thanks(0) Quote Reply Topic: Turn off WAAS/Egnos without going into maintenance Posted: 10 Feb 2022 at 6:26am
	Is there any way in normal operational mode (not maintenance) to turn off EGNOS so that a 2D RNP approach can be flown at an airfield where LPV is available? Europe skill tests require both 3D and 2D approaches. VOR approaches are rapidly going the way of the dodo bird and NDB are in many countries (almost) gone. Many airfields now have only ILS and RNP LPV approaches to choose from, which gives no possibility to do a 2D approach. Garmin has a user setting to turn off EGNOS/WAAS which then reverts all RNP approaches to LNAV only. This would be useful for the IFD too, but I haven't so far found a way to do it.
	Vince

AviSteve Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Joined: 12 Feb 2018 Location: Melbourne, FL Status: Offline Points: 2161	Post Options Post Reply Quote AviSteve Report Post Thanks(0) Quote Reply Posted: 10 Feb 2022 at 9:30am
	The only way is through maintenance mode.
	Steve Lindsley Avidyne Engineering

chflyer Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 24 Jan 2013 Location: LSZK Status: Offline Points: 1022	Post Options Post Reply Quote chflyer Report Post Thanks(0) Quote Reply Posted: 10 Feb 2022 at 9:37am
	What I thought. Please add this to the feature request list for a future release. Without it, doing checkflights will become increasingly challenging due to lack of availability of 2D approaches.
	Vince

ColinW Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 24 May 2016 Location: EGGP Liverpool Status: Offline Points: 24	Post Options Post Reply Quote ColinW Report Post Thanks(0) Quote Reply Posted: 10 Feb 2022 at 12:16pm
	I used a strip of PostIt to cover the GS indicator on our Avidyne PFD for my skills test, but I appreciate this wouldn’t work for a round instrument.

chflyer Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 24 Jan 2013 Location: LSZK Status: Offline Points: 1022	Post Options Post Reply Quote chflyer Report Post Thanks(0) Quote Reply Posted: 11 Feb 2022 at 8:39am
	I have a G5 and Sandel which both show the GS. I've tried your approach, but without any real success.
	Vince

chflyer Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 24 Jan 2013 Location: LSZK Status: Offline Points: 1022	Post Options Post Reply Quote chflyer Report Post Thanks(0) Quote Reply Posted: 29 Mar 2022 at 7:07am
	I would like to ask that this ability be added ASAP (turn off WAAS/SBAS/EGNOS). It is available on G* equipment. Flying non-precision approaches is still part of the IR syllabus (or 2D as they are called here in Europe) and required for an IPC or skill test. By not being able to turn off the glideslope indication, the only option (other than a PostIt which is not really effective with newer equipment such as G5 or an HSI) is to try to find a VOR approach. There is only one in Switzerland (other than Geneva and Zurich where training flights are discouraged) and it could disappear anytime. Normally, an LNAV approach would also qualify. But they are all now shown by the Avidyne as LNAV+V with an advisory glideslope, which is not any better. This should be easy to implement as a AUX/USER setting, just like FLTA. Edited by chflyer - 29 Mar 2022 at 7:13am
	Vince

chflyer Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 24 Jan 2013 Location: LSZK Status: Offline Points: 1022	Post Options Post Reply Quote chflyer Report Post Thanks(0) Quote Reply Posted: 08 Apr 2022 at 5:49am
	I've just noticed that even flying a VOR approach won't address this requirement anymore, since most are now (GPS) VOR, i.e. allow GPS overlay. I tried to fly a "(GPS) VOR/DME" approach recently and was surprised that while I was able to load it from the navdata, when it came time to fly it there was no GPS->VLOC as is the case for an ILS. Rather, the IFD presented me with a GPS->LNAV+V and this sequenced to LNAV+V once established on final track. So my CDI guidance was GPS-based rather than VOR-based despite having loaded a VOR approach. So as long as GPS is performing properly there is no chance with the IFD to fly an approach without a vertical indication of some sort, either guidance or advisory. Does the FAA IR no longer require demonstration of a 2D approach (i.e. without vertical guidance)? I agree that LNAV is a 2D approach, but there is no chance to remove the vertical advisory indication. In real life of course this is a good thing. But it does eliminate the ability to practice for the case when GPS is out of service which seems to not be uncommon in parts of the US. It would be nice to be able to easily switch off WAAS/Egnos to allow practice. Edited by chflyer - 08 Apr 2022 at 5:51am
	Vince

oskrypuch Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 09 Nov 2012 Location: CYFD Status: Offline Points: 3058	Post Options Post Reply Quote oskrypuch Report Post Thanks(0) Quote Reply Posted: 08 Apr 2022 at 10:55am
	Once established, if you had twisted the top right knob, you should have received VOR sensing/direction. You may have had to select that mode on your PFD as well. And, for at least the +VNAV sensing, that you can turn off temporarily, or otherwise, about 2/3rds of the way down the the options page (Advisory Glideslope). You can't selectively disable "real" VNAV on an ILS or LPV approach. * Orest

chflyer Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 24 Jan 2013 Location: LSZK Status: Offline Points: 1022	Post Options Post Reply Quote chflyer Report Post Thanks(1) Quote Reply Posted: 08 Apr 2022 at 7:02pm
	Many thanks Orest. Yes, you're right. Now that you mention it, I did indeed manually turn the top right knob to get VLOC. So the take-away is that to do a "real" VOR approach, the VLOC needs to be selected manually. I can only assume that this is different from the ILS because for an ILS there is no GPS overlay. Where a GPS overlay is available in the official chart, then the IFD apparently gives it priority over the VOR. That makes sense too, since GPS guidance is much more stable than VHF and that is especially so for VOR. Regarding the options page, I don't know how I missed that one. The description in the manual appears to be exactly what I'm looking for, at least for VOR or LNAV approaches. Most approaches here with LNAV minimums also have LPV, so that won't work so often. But I'll try it out on my next VOR approach to confirm that it performs as expected.
	Vince