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Garmin GNS430 & 530 versus 430W/530W (and approach coding)

Forgive me if this has been covered before, but what are the practical imitations on using the non-WAAS versions for IFR flying and approaches (referring here to N-registered type)?

I do understand if a bit sketchily about RAIM in a US context, but I wonder about restricting what these items can legally be used for in Europe, if not WAAS.

Upgrading seems to be possible at a cost.

Relevant advice welcome!

Bluebeard
EIKH, Ireland

You won’t be able to do LPV approaches to 250 DA without WAAS so you will be limited to the LNAV minima. With WAAS you will also benefit from vertical guidance for approaches labeled by Jeppesen as LNAV+V

LFPT, LFPN

Aviathor wrote:

You won’t be able to do LPV approaches to 250 DA without WAAS so you will be limited to the LNAV minima. With WAAS you will also benefit from vertical guidance for approaches labeled by Jeppesen as LNAV+V

You won’t be able to do LPV approaches to any minima at all without WAAS. You also won’t get LNAV/VNAV with SBAS guidance. With WAAS you may also get a +V from Garmin on LNAV approaches. So without WAAS you will never get vertical guidance on GPS approaches. The best you can hope for is LNAV ie a very usable replacement for NDB and VOR approaches.

And RAIM is only relevant to non-WAAS boxes.

Last Edited by JasonC at 27 Oct 22:14
EGTK Oxford

JasonC wrote:

And RAIM is only relevant to non-WAAS boxes.

True that RAIM is always relevant to non-WAAS boxes but AFAIK it is also relevant to WAAS boxes when there is no WAAS (SBAS) coverage…

Last Edited by AnthonyQ at 27 Oct 22:37
YPJT, United Arab Emirates

AnthonyQ wrote:

True that RAIM is relevant to non-WAAS boxes but AFAIK it is also relevant to WAAS boxes when there is no WAAS (SBAS) coverage…

Well yes, you got me there.

EGTK Oxford

Aviathor wrote:

You won’t be able to do LPV approaches to 250 DA without WAAS

Well according to Part-NCO system minima for LPV approaches are now 200 ft. That must mean that if OCH for the LPV is lower than 250 ft (which is is for all LPV’s in my countries), then you can, with WAAS, fly an LPV down to OCA(H) or to 200 ft AAL, whichever is higher.

So even if Jeppesen says 250 ft DH on all 6 of LPV’s in my country, I will now fly them down to DH = 200 ft (except one with an OCH of 208 ft, all other OCH’s are below 200 ft).
As I see it, we can go 50 ft lower than the Jeppesen DA ( H ), legally.

Last Edited by huv at 29 Oct 14:50
huv
EKRK, Denmark

huv wrote:

So even if Jeppesen says 250 ft DH on all 6 of LPV’s in my country, I will now fly them down to DH = 200 ft (except one with an OCH of 208 ft, all other OCH’s are below 200 ft).
As I see it, we can go 50 ft lower than the Jeppesen DA ( H ), legally.

LPV with a DH of 200 and LPV with a DH of 250 are different approaches. The VAL requirements for the DH 200 is set to 35 meters and for the DH 250 to 50 meters. I would be surprised if an ICAO country would permit busting the DH 250. You would certainly be violated in the US if you were caught busting a DH.

KUZA, United States

VAL?

Biggin Hill

NCYankee wrote:

LPV with a DH of 200 and LPV with a DH of 250 are different approaches

I have certainly seen the notion “LPV200 approach” indicating that it is a different creature from “LPV” once you go below 250 ft DH. But I find nothing in Part-NCO indicating that:

NCO.OP.111 Aerodrome operating minima — NPA, APV, CAT I operations
(a) The decision height (DH) to be used for a non-precision approach (NPA) flown with the
continuous descent final approach (CDFA) technique, approach procedure with vertical
guidance (APV) or category I (CAT I) operation shall not be lower than the highest of:
(1) the minimum height to which the approach aid can be used without the required visual
reference;
(2) the obstacle clearance height (OCH) for the category of aircraft;
(3) the published approach procedure DH where applicable;
(4) the system minimum specified in Table 1; or
(5) the minimum DH specified in the AFM or equivalent document, if stated.
(b) The minimum descent height (MDH) for an NPA operation flown without the CDFA technique
shall not be lower than the highest of:
(1) the OCH for the category of aircraft;
(2) the system minimum specified in Table 1; or
(3) the minimum MDH specified in the AFM, if stated.
Table 1 gives “Lowest DH/MDH (ft)” for “Global navigation satellite system (GNSS)/Satellite-based
augmentation system (SBAS) (Lateral precision with vertical guidance approach (LPV))” to 200 ft

According to this
Eurocontrol document, LPV system minima is 200 ft AND the required VAL is 50 m.

Last Edited by huv at 30 Oct 17:51
huv
EKRK, Denmark

NCYankee wrote:

LPV with a DH of 200 and LPV with a DH of 250 are different approaches. The VAL requirements for the DH 200 is set to 35 meters and for the DH 250 to 50 meters. I would be surprised if an ICAO country would permit busting the DH 250. You would certainly be violated in the US if you were caught busting a DH.

Does the US publish DH? Most ICAO countries do not. They publish OCH and it is then up to the PIC to determine the DH.

ESKC (Uppsala/Sundbro), Sweden
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