Garmin 480 Boletim informativo do utilizador - Página 2

Procurar online ou descarregar pdf Boletim informativo do utilizador para GPS Garmin 480. Garmin 480 5 páginas. Color gps/waas/nav/com
Também para Garmin 480: Boletim informativo do utilizador (6 páginas), Manual de voo suplementar (10 páginas), Referência rápida (25 páginas)

What's with all these different approach names?

There have been a number of questions regarding when and where you will receive vertical guidance from the GNS 480. Much of

this was discussed in the prior newsletter, but there are exceptions to the general rules and some examples would be helpful,

especially given the vagaries of the Jeppesen charts and almost no usable information in the NOS charts. Bear in mind that all these

approaches can be selected and flown the same way, even though they have different depictions and names associated with them.

While the data can be confusing, flying an approach with vertical guidance is actually straightforward in terms of execution. We can

review the basics here along with the approach nomenclature that goes along with these approaches:

1. For vertical guidance on the approach you must a) select a GPS approach (either standalone or overlay, and not a VOR or

NDB only approach) from the database and b) be in WAAS coverage with adequate horizontal and vertical position

accuracy. Currently only approaches within the continental US have the data to support vertical guidance.

2. Vertical guidance is provided for three distinct types of approaches as shown on the approach charts: LPV, Lnav/Vnav, and

Lnav approaches with advisory vertical guidance. From a pilot's perspective, all approaches with vertical guidance behave

similarly and can be flown using the same techniques as you would an ILS approach.

3. If the GNS 480 can provide vertical guidance on the approach, it will be labeled as an Lnav/Vnav or LPV approach when

you select it from the database (green text under the approach name). Lnav approaches that have advisory vertical guidance

will also be shown as Lnav/Vnav approaches in the database, but will have no Lnav/Vnav minimums shown on the approach

chart. In this case Lnav MDA minimums are controlling.

4. Verify the Lnav/Vnav or LPV annunciator is green (on the MAP or NAV page) once past the IAF. If it is amber, the GPS

constellation may not be able to support vertical guidance and the GNS 480 will downgrade to an Lnav only approach 30

seconds prior to the FAF if the vertical protection limit is inadequate at that point. In rare instances if an Lnav approach

cannot be supported, you will be notified and be required to abort the approach. The 480 will fall back to terminal limits of

1NM to provide guidance to the missed approach, or other waypoint as cleared by ATC.

Unfortunately NOS approach charts do not depict advisory vertical guidance as do most Jeppesen charts. At this point we have not

found a reliable method of determining if an approach supports advisory vertical guidance from the NOS charts, and have made

requests for changes making the charts more definitive. Whether or not this request will be successful at all is anyone's guess. The

most reliable method of knowing if vertical navigation will be displayed is from the GNS 480 itself, as it displays this data when the

procedure is selected. You may survey the GPS approaches at your destination to see which approaches support vertical navigation

without inserting one into your flight plan by using the Procedure key and selecting APPR at your destination.

Vertical guidance does not terminate at the MDA or DA. This is consistent with other systems (notably Flight Management Systems)

that project vertical paths to a point in space. The vertical path extends to either the MAP or runway end waypoint depending upon

the type of approach, and terminates at the altitude associated with the waypoint. This data is drawn from the database. Typically the

altitude associated with the waypoint is 50' AGL for an LPV precision approach, and higher for non-precision approaches. The path

angle will typically be in the 3 degree range, but may be adjusted for obstacles as a glideslope might be.

It should also be noted that the limitation for local altimeter setting is not required as it is for aircraft with FMS/Baro-Vnav systems.

The vertical path does not require baro-correction and is generated solely by use of GPS altitude. Local altimeter settings are only

required to determine MDA or DA on your altimeter.