Do I have the required equipment for LPV?

RalphInCA

RalphInCA

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RalphInCA
Possibly a dumb question, but when determining the approach to use for a GPS approach (and associated minimums) how can I determine if I have the required equipment for an LPV approach, vs a LNAV/VNAV approach?
 
Look at the panel. Does it have a certified WAAS GPS? Load the approach. Does the GPS indicate LPV?
 
First, look at the panel. See any WAAS GPS equipment? If so....

Does such equipment indicate LPV mode? (Garmin does)
Do you have RAIM?

Then you should be okay. But there is a lot of equipment specific stuff leading to following that glide slope to mins.

EDIT: Looks like I'm just repeating @Clark1961
 
rolivi said:
First, look at the panel. See any WAAS GPS equipment? If so....

Does such equipment indicate LPV mode? (Garmin does)
Do you have RAIM?

Then you should be okay. But there is a lot of equipment specific stuff leading to following that glide slope to mins.

EDIT: Looks like I'm just repeating @Clark1961
Click to expand...
It's sort of funny because even the certified WAAS box can not indicate LPV if it isn't configured correctly. Don't ask me how I know this...
 
Clark1961 said:
If it is a 430w then it is WAAS. No w, no WAAS.
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Not necessarily if you are just referring to the screen print of the "430" vs "430w" on the bezel. If the panel says 430w then it is WAAS, but a 430 can be upgraded without the "w" being indicated on the bezel. That was the case with my plane when I got it...it only said 430 but had indeed been upgraded to WAAS somewhere along the way.

So as mentioned above, if it does not say 430w on the panel...check the startup screen.
 
Shawn said:
Not necessarily if you are just referring to the screen print of the "430" vs "430w" on the bezel. If the panel says 430w then it is WAAS, but a 430 can be upgraded without the "w" being indicated on the bezel.
Click to expand...

Yup, when the W's came out, Garmin ran a lower cost upgrade special for a limited time, we took advantage of that and upgraded the 430 to WAAS.
 
Bill Jennings said:
Yup, when the W's came out, Garmin ran a lower cost upgrade special for a limited time, we took advantage of that and upgraded the 430 to WAAS.
Click to expand...

Currently $3,695 from Garmin plus any shop time needed to upgrade the 430/530 to WAAS.
 
Also check the AFM Supplement...I've seen a couple of instances where the owner chose not to certify the full capability of the box for some reason.
 
Shawn said:
Not necessarily if you are just referring to the screen print of the "430" vs "430w" on the bezel. If the panel says 430w then it is WAAS, but a 430 can be upgraded without the "w" being indicated on the bezel. That was the case with my plane when I got it...it only said 430 but had indeed been upgraded to WAAS somewhere along the way.

So as mentioned above, if it does not say 430w on the panel...check the startup screen.
Click to expand...

OK, THIS is what has been confusing me.

I just recently flew in an airplane that had a 430, it was WAAS, but on the nameplate all it said was 430.

The primary airplane I fly has a 430 - no W on the nameplate - and I know for a fact it is not WAAS.
 
The datapages are the whole story. Version and DB expiration dates are key to all this.

So, our previous advice should have been - Master Switch ON - Avionics Master ON - Look at GPS looking things for W and current databases
 
MauleSkinner said:
Also check the AFM Supplement...I've seen a couple of instances where the owner chose not to certify the full capability of the box for some reason.
Click to expand...

THAT.

If you don't have the paperwork, it ain't a WAAS plane, even if it is a WAAS box.

A WAAS GNS box will also say 430W on the start up screen
 
Shawn said:
Not necessarily if you are just referring to the screen print of the "430" vs "430w" on the bezel. If the panel says 430w then it is WAAS, but a 430 can be upgraded without the "w" being indicated on the bezel. That was the case with my plane when I got it...it only said 430 but had indeed been upgraded to WAAS somewhere along the way.

So as mentioned above, if it does not say 430w on the panel...check the startup screen.
Click to expand...
Did I say I was referring to the nameplate? No I said if it is a 430w then it is WAAS. It also has to be configured correctly. All this has been mentioned previously.
 
Clark1961 said:
Did I say I was referring to the nameplate? No I said if it is a 430w then it is WAAS. It also has to be configured correctly. All this has been mentioned previously.
Click to expand...

Easy there Tiger...you also said "no w, no WAAS" which is not necessarily the case if you are looking at the faceplate...which had not been mentioned perviously...hence the clarification to what you said to avoid confusion.
 
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Everyone is worried about the box. You also need a display head CDI with a "glide slope" bar.
I've seen installations without the proper display head.
 
Shawn said:
Currently $3,695 from Garmin plus any shop time needed to upgrade the 430/530 to WAAS.
Click to expand...

They lost a bunch of money on that $1,500 upgrade. After they did the price computation, and made the commitment, the friendlies told Garmin they would have to increase the internal update rate, thus a lot of significant hardware changes that had not been considered in the $1,500 upgrade.
 
If they hadn't offered the $3000 upgrade promise, they'd have been in a world of hurt at the time. Nobody would have bought a straight 430 while they were getting the bugs out of their certification without a definite upgrade path.

Garmin always said that the $3000 upgrade was a limited time offer. They knew it was a loss right then and there.
 
flyingron said:
If they hadn't offered the $3000 upgrade promise, they'd have been in a world of hurt at the time. Nobody would have bought a straight 430 while they were getting the bugs out of their certification without a definite upgrade path.

Garmin always said that the $3000 upgrade was a limited time offer. They knew it was a loss right then and there.
Click to expand...

It was a Garmin senior avionics engineer that told me what I posted. The price of $1,500 is my recollection, but that could be wrong.
 
There is a 2007 thread in Maintenance Bay on this forum that mentions the $1,500 upgrade price.
 
Can you also check the color of data card? I was under the assumption the WAAS cards are white regular cards are green.
 
tree96 said:
Can you also check the color of data card? I was under the assumption the WAAS cards are white regular cards are green.
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That just tells you which database you have, not what the unit was certified to do at installation.
 
On the Garmins what matters is what it says on the approach screen. If you have LPV with appropriate signal it will say "LPV"

As others have mentioned there are a lot of 430s that are now 430Ws even though it doesn't say so on the hardware. Check the boot up screen but then also at the end of the day what really matters is what it says on the approach screen. That's telling you how low you can go.
 
rocketflyer84 said:
On the Garmins what matters is what it says on the approach screen. If you have LPV with appropriate signal it will say "LPV"

As others have mentioned there are a lot of 430s that are now 430Ws even though it doesn't say so on the hardware. Check the boot up screen but then also at the end of the day what really matters is what it says on the approach screen. That's telling you how low you can go.
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Pretty sure it's not just Garmins. My CNX-80 (okay, Garmin bought them out, but it's not a Garmin design) also does that. I think I read somewhere that an annunciation of the approach level supported at the time the approach is begun is one of the certification requirements for an approach certified GPS, but that was a while ago and my memory may be faulty. What I'm sure of is that if the required vertical (or horizontal) integrity is not present, the unit will downgrade the approach. So say the required integrity for LPV is not available, but the required integrity for LNAV minimums is, my CNX-80 will say LNAV. So, as you say, what matters is what it says on the approach screen, which may not be the same every time you fly the approach.
 
Any GPS is going to have to tell you if it's in LPV mode. How else are you going to know which set of minimums to use for the approach.
 
To fly an LPV approach, I understand that you need these things:

1. Hardware. Must be a WAAS GPS approved for IFR approach use. The 430W or 430 with WAAS upgrade meets this. Check the startup screen for details.
2. Installation. Must be approved for IFR use. I saw a 430W installation with "VFR ONLY" written on it, so I passed on that plane. It apparently can cost more to get IFR approval of a VFR install than it does to do a new install, but it depends on the reasons for the lack of IFR approval. It can range from antenna cables to annunciator placement on the panel.
3. Database. Must be current or have the right waypoints. My tip on this is to check the revision date of the approach plate and compare it to the database date. If they didn't change the plate since they updated the database, it should be fine.
4. Signal. RAIM prediction or just look for the LPV annunciation on the unit.
 
There are instructions in the GTN650/750 installation manual written for VFR only installations...
 
A 430 with a WAAS upgrade *IS* a 430W.

There's not much to certifying the installation other than running a flight test (You need to fly one GPS approach) and filing the paperwork.

There's nothing magic about LPV approaches with databases. The database requirements are going to be spelled out in the flight manual supplement for use of ANY approach.

Similarly, there's nothing magic about LPV for RAIM either. RAIM checks are done by the hardware for all GPS-based approaches.
 
flyingron said:
A 430 with a WAAS upgrade *IS* a 430W.
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It's a matter of semantics. I'm sure they are impossible to distinguish other than the badge.

There's not much to certifying the installation other than running a flight test (You need to fly one GPS approach) and filing the paperwork.
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I've read that deficiencies can vary, including the lack of annunciation or a badly placed CDI or a VFR-only antenna cable installation and other such insanities.

There's nothing magic about LPV approaches with databases. The database requirements are going to be spelled out in the flight manual supplement for use of ANY approach.
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That's true. I didn't mean to imply that the database would be different, just that it does have to meet the requirements for flying the approach, regardless of minimums you fly it to.

Similarly, there's nothing magic about LPV for RAIM either. RAIM checks are done by the hardware for all GPS-based approaches.
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If they come up short, does it fall back to LNAV or refuse to fly the approach?
 
ADepends on what the integrity numbers come up to. Either is a possibility.

You are right, there could be other issues with the installation. THere's no such thing as VFR coax. If the coax is deficient, I suspect you don't have a legal installation for ANY purpose. There aren't any VFR antennas either. There are antennas that will preclude you from using them for WAAS (i.e., LPV approach). You are right that there are specific placement requirements for the external CDI for IFR use (even for using the VOR/LOC/GS part) and annunciator if the on-screen one is too far from the center of view.
 
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flyingron said:
A 430 with a WAAS upgrade *IS* a 430W.

There's not much to certifying the installation other than running a flight test (You need to fly one GPS approach) and filing the paperwork.

There's nothing magic about LPV approaches with databases. The database requirements are going to be spelled out in the flight manual supplement for use of ANY approach.

Similarly, there's nothing magic about LPV for RAIM either. RAIM checks are done by the hardware for all GPS-based approaches.
Click to expand...

WAAS GPS does not use RAIM for LPV, it uses WAAS HPL and VPL (Horizontal or Vertical Position Limit) which are determined by the WAAS integrity data. RAIM is based on internal calculations and the A stands for Autonomous, meaning the integrity data is calculated without any augmentation and is all an internal calculation. RAIM effectively compares different combinations of satellites to produce multiple positions and how much variance in the various position calculations is used to estimate the likely bounds on the position error. With WAAS, the integrity data is broadcast by the WAAS satellites, and there is an error metric available for each satellite. A WAAS GPS only reverts to using RAIM when outside of the WAAS service volume or during a complete WAAS satellite/system failure.
 
flyingron said:
ADepends on what the integrity numbers come up to. Either is a possibility.

You are right, there could be other issues with the installation. THere's no such thing as VFR coax. If the coax is deficient, I suspect you don't have a legal installation for ANY purpose. There aren't any VFR antennas either. There are antennas that will preclude you from using them for WAAS (i.e., LPV approach). You are right that there are specific placement requirements for the external CDI for IFR use (even for using the VOR/LOC/GS part) and annunciator if the on-screen one is too far from the center of view.
Click to expand...
According to a 2002 Avweb article, there are TSO requirements for the installation process, antenna, and coax that may not be met with a VFR-only installation. I agree, there's no such thing as VFR coax or antennas. They either pick up and deliver GPS/WAAS signals or they don't. But the relevant TLA here seems not to be IFR or VFR, but TSO. That information could be as obsolete as it is old, though. What I do know is that paperwork is required to use the GPS to navigate under IFR.
 
As I said, there's definitely restrictions on the antenna for LPV use, but if your "coax" isn't right, I suspect your VFR installation isn't legal either.
 
flyingron said:
A 430 with a WAAS upgrade *IS* a 430W.

There's not much to certifying the installation other than running a flight test (You need to fly one GPS approach) and filing the paperwork.

There's nothing magic about LPV approaches with databases. The database requirements are going to be spelled out in the flight manual supplement for use of ANY approach.

Similarly, there's nothing magic about LPV for RAIM either. RAIM checks are done by the hardware for all GPS-based approaches.
Click to expand...
Wait, are we talking about an ordinary non-WAAS GPS or WAAS? I didn't think RAIM was used at all by WAAS units as long as WAAS was available.
 
As pointed out, if there is WAAS, there is no need for RAIM, but all the WAAS navigators still support it so they can fall back in case the augmentation signal isn't available.
 
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