LNAV/VNAV Only

All of the SBAS boxes I’ve dealt with were certified before LP existed, and can fly LPV but not LP.

but again, it’s the documentation that provides the answer, not assumptions, no matter how logical they may be.

Flying LP or LP+V is dependent on the software version for the GNS (3.30 added LP, 5.10 added LP+V, current version is 5.40), GTN (LP was approved in the initial release 2.0, 6.11 added LP+V, current version 6.70), and G1000 systems. Early GNS and G1000 systems don't support LP or LP+V, but if the software is upgraded, they do.
 
The disagreement I mentioned (and am not answering) is what happens if you have LNAV/VNAV minimums lower than LPV minimums and the system annunciates LPV. Can you fly to the lower LNAV/VNAV minimums?

This was an issue we ran into more than 12 years ago when I was a contractor on the WAAS program. At the time, this generally happened when the LPV approach was designed using a different survey from what was used to design the LNAV/VNAV. I figured by now most of those situations would have been corrected.
 
This was an issue we ran into more than 12 years ago when I was a contractor on the WAAS program. At the time, this generally happened when the LPV approach was designed using a different survey from what was used to design the LNAV/VNAV. I figured by now most of those situations would have been corrected.
My home base, KTTA, has one n the GPS 21. It's only 12 feet and 1/8 mile vis, so it's not too significant practically speaking. But it is an interesting academic exercise.

upload_2020-2-9_11-20-46.png
 
There are RNAV approaches with LNAV/VNAV minimums in Puerto Rico that are not approved for WAAS VNAV. Example is TJSJ RNAV (GPS) Rwy 10 which has LNAV/VNAV DA but also has the note "WAAS VNAV not authorized". Otherwise, AC 90-105A permits using WAAS for vertical navigation in appendix A that deals with RNP APCH:

A.6.4 LNAV/VNAV Line of Minima Qualification.
A.6.4.1 Stand-Alone Systems. Stand-alone TSO-C146 Class 2 or 3 systems meet the aircraft qualification requirements for RNP APCH operations using the LNAV/VNAV line of minima provided that the installations meet at least the performance and functional requirements of this AC.

I am of the opinion that as long as the WAAS system annunciates LPV or L/VNAV, flying to the LNAV/VNAV DA minima is permitted, even in the rare case where the LNAV/VNAV minima is lower than the LPV. The same logic permits the pilot to choose to use the charted LNAV or Circling LNAV procedure and minima on an approach when an the annunciation is any of the following: LPV, L/VNAV, LP, LP+V, LNAV+V, or LNAV.
 
Flying LP or LP+V is dependent on the software version for the GNS (3.30 added LP, 5.10 added LP+V, current version is 5.40), GTN (LP was approved in the initial release 2.0, 6.11 added LP+V, current version 6.70), and G1000 systems. Early GNS and G1000 systems don't support LP or LP+V, but if the software is upgraded, they do.

I love that software updates can make things better.

I loathe that in aviation this isn’t just automatic like every other piece of significant software that I own or rent.

It’s utterly stupid that we have to schedule time in a shop to upload stuff from an iPad to the panel, considering the state of the art in all other software.

“There’s a new update. Install? (y/n)” should be the norm by now.
 
I love that software updates can make things better.

I loathe that in aviation this isn’t just automatic like every other piece of significant software that I own or rent.

It’s utterly stupid that we have to schedule time in a shop to upload stuff from an iPad to the panel, considering the state of the art in all other software.

“There’s a new update. Install? (y/n)” should be the norm by now.
Unfortunately there’s also certification that has to take place before software can be changed. You’d have to install the update as well as the new manuals and avionics tech signature for your installation.
 
Flying LP or LP+V is dependent on the software version for the GNS (3.30 added LP, 5.10 added LP+V, current version is 5.40), GTN (LP was approved in the initial release 2.0, 6.11 added LP+V, current version 6.70), and G1000 systems. Early GNS and G1000 systems don't support LP or LP+V, but if the software is upgraded, they do.
I love the way Garmin has everyone assuming that no other avionics manufacturers exist.

it’s kind of like talking about furniture and people asking which IKEA store you went to. ;)
 
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Unfortunately there’s also certification that has to take place before software can be changed. You’d have to install the update as well as the new manuals and avionics tech signature for your installation.

Understood. It’s outdated.

Print the new manual at home yourself and upload the update. Done.

There’s nothing special about my avionics guy’s crappy inkjet printer over my much better color laser one.

Ramp check me. If I didn’t print the damn thing, cite me. I’ll print it. Not rocket science.

What’s the tech signature adding? If the update software says it worked, he’s signing. He didn’t write the code and didn’t do anything. His iPad isn’t any better than mine.

If it requires a flight test, that’s different. But a firmware update? Just move that to the owner/operator. There’s no value add anymore for avionics shop firmware updates unless you just don’t feel like doing it.
 
Understood. It’s outdated.

Print the new manual at home yourself and upload the update. Done.

There’s nothing special about my avionics guy’s crappy inkjet printer over my much better color laser one.

Ramp check me. If I didn’t print the damn thing, cite me. I’ll print it. Not rocket science.

What’s the tech signature adding? If the update software says it worked, he’s signing. He didn’t write the code and didn’t do anything. His iPad isn’t any better than mine.

If it requires a flight test, that’s different. But a firmware update? Just move that to the owner/operator. There’s no value add anymore for avionics shop firmware updates unless you just don’t feel like doing it.
Probably get there eventually...it hasn’t been much more than 25 years ago now that we had to find a live weather observer so we could shoot an approach under Part 135 because we didn’t have a training program on how to use AWOS/ASOS.
 
Probably get there eventually...it hasn’t been much more than 25 years ago now that we had to find a live weather observer so we could shoot an approach under Part 135 because we didn’t have a training program on how to use AWOS/ASOS.

Yeah. We can already update the database which has plenty of possibility to kill us. Updating firmware really is no different if the devices are handling error checking and such. And printing the PDF from the website to cram into page X - Y of the aircraft manual isn’t exactly a big deal.

Not sure that the avionics person’s signature really buys in that process other than they have secret squirrel access to that web page at Garmin, these days.
 
Yeah. We can already update the database which has plenty of possibility to kill us. Updating firmware really is no different if the devices are handling error checking and such. And printing the PDF from the website to cram into page X - Y of the aircraft manual isn’t exactly a big deal.

Not sure that the avionics person’s signature really buys in that process other than they have secret squirrel access to that web page at Garmin, these days.
I would agree that we should be able to update the software version ourselves. However having just sat with my avionics shop as the updated my GTN they told me several steps along the way that if done in the wrong order etc would (and has) brick the unit. Not that that couldn’t be communicated in a readme file or instructions but something to be careful with in a $15k instrument.
 
I would agree that we should be able to update the software version ourselves. However having just sat with my avionics shop as the updated my GTN they told me several steps along the way that if done in the wrong order etc would (and has) brick the unit. Not that that couldn’t be communicated in a readme file or instructions but something to be careful with in a $15k instrument.

I can read step by step instructions I’ve never done before just as easily as my avionics guy who also often hasn’t, depending on popularity of the product line and such.

And the manufacturer can simply code the correct order into the iPad uploader anyway. They don’t mostly out of laziness because they can just blame the dealer when he missed the asterisk on page 27 of their PDF. LOL.

The rest of the world has automated much more detailed and difficult tasks, is all I’m sayin’. I don’t hold my breath when speaking of aviation tech ever catching up.

My car emailed me this morning. LOL. I also unlocked it with a phone app and it emailed me about that too. Ironically it needs a dealership to update firmware for a much more common reason than the airplane: Capturing money at higher prices than competitors at the service dept.

“Well since it’s in here to fix your broken software for free, you might as well charge me double the going rate for an oil change...” Heh.

At least the avionics shop doesn’t want to change my oil. Ha.
 
Just curious, what avionics can you update software on via iPad?

Software? You currently can’t I don’t think.

But Concierge updates all databases from either iOS or Android on Garmin stuff equipped with a Flightstream device, just fine.

I was saying there’s zero reason why what Concierge does for databases, can’t be done with firmware updates.

But you’re right, aviation is probably so far behind it also probably needs a PC and can’t even be done from OSX, let alone iOS. Probably Windows 7 even. LOL.

Folks with 430 and 530 still need those “special” SD card writers too, right?

It’ll be another decade before we see a USB-C port on anything in a light aircraft, probably.

Who knows? Some manufacturer might surprise us. :)
 
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