Authority to shoot WAAS approaches

[Bernoulli Fan]

Another CFI and I are discussing what gives a pilot the authority to shoot an approach to LPV minimums. The G1000 just shows whatever it decides it's using; the only thing the pilot can do is verify WAAS reception is enabled.

We've searched the POH and supplements, along with the G1000 cockpit reference guide (both the quick guide in the plane and the huge version online), but can't find anything concrete.

I contend that a pilot doesn't need anything that says "You can use LPV minimums because your GPS is WAAS capable" in a POH or supplement -- you are either capable and able to use those mins, or not. But the other CFI is convinced you do need express authorization.

Thoughts? Are we missing something obvious?

 

[braunpilot]

Of the only information that I have seen the GPS unit has to inform you if you can use the LPV, LNAV/VNAV, LNAV on the approach plate. It sort of stinks but you have to be able to do some quick planing right at the tail end of the approach. But I cannot quote any document. I saw it in a video.

 

[BrewMaster]

AIM 5-4-5 k. 1. (b)

(b) LPV. "LPV" is the acronym for localizer performance with vertical guidance. LPV identifies WAAS APV approach minimums with electronic lateral and vertical guidance. The lateral guidance is equivalent to localizer and the protected area for LPV procedures is now the same as for an ILS. The obstacle clearance area is considerably smaller than the LNAV/VNAV protection, allowing lower minima in many cases. Aircraft can fly this minima line with a statement in the Aircraft Flight Manual that the installed equipment supports LPV approaches. This includes Class 3 and 4 TSO-C146 WAAS equipment.

Hopefully this is what you were looking for.

 

[Bernoulli Fan]

Aircraft can fly this minima line with a statement in the Aircraft Flight Manual that the installed equipment supports LPV approaches. This includes Class 3 and 4 TSO-C146 WAAS equipment.

Hopefully this is what you were looking for.

This is what we are looking for, but we can't find such a statement in the 172's POH. The G1000 cockpit reference guide says "For those systems with WAAS capability..." many times, but never specifies which systems have it.

We went online and found the part number of the GPS unit that has WAAS capability (GIA 6XW), so I guess by extension, any supplement that mentions that part number implies you have the proper equipment.

 

[Cessnaflyer]

Well the GPS or in your case the G1000 display has to specifically say LPV in the section of the display that states what phase of flight you are in "Enroute, Terminal, Approach, LNAV/VNAV or LPV" It is in the software to determine if you are able to do this. The Garmin 430's are all in the same box but the software installed in that box determins if you can use the WAAS or LAAS approach.

 

[bdhill1979]

Well the GPS or in your case the G1000 display has to specifically say LPV in the section of the display that states what phase of flight you are in "Enroute, Terminal, Approach, LNAV/VNAV or LPV" It is in the software to determine if you are able to do this. The Garmin 430's are all in the same box but the software installed in that box determins if you can use the WAAS or LAAS approach.

:yeahthat:almost, the 430/530 series upgrade involves hardware, but not much.

As to the G1000 it will say right in the HSI what mode it is in, that and in LPV mode you will see a Magenta "glideslope"

 

[sundog]

We went online and found the part number of the GPS unit that has WAAS capability (GIA 6XW), so I guess by extension, any supplement that mentions that part number implies you have the proper equipment.

I believe that WAAS capability is a(n expensive) software upgrade on the g1000, so your plane may or may not have it, but the owner/operator will certainly know if they paid for the option. I know at the flight school i use, some of the lease-back diamonds got the upgrade last year and some did not, based on the owner's finances. but all of them were capable of getting the upgrade.

 

[bdhill1979]

I believe that WAAS capability is a(n expensive) software upgrade on the g1000, so your plane may or may not have it, but the owner/operator will certainly know if they paid for the option. I know at the flight school i use, some of the lease-back diamonds got the upgrade last year and some did not, based on the owner's finances. but all of them were capable of getting the upgrade.

It is also a hardware addition

and last I checked it costs about $15,000 for a G1000

 

[Douglas]

By the power vested in me...

 

[Bernoulli Fan]

By the power vested in me...

That's what I said. By most of the responses, seems like most agree.

 

[Cessnaflyer]

:yeahthat:almost, the 430/530 series upgrade involves hardware, but not much.

As to the G1000 it will say right in the HSI what mode it is in, that and in LPV mode you will see a Magenta "glideslope"

Yeah exactly. That thing is so expensive I'm lucky our RG has it and the cost of that aircraft is about the same for all other reantal 172's in the area!