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Need to be sure of your avionics doing this

Wow. Instrument approaches have come a long way, I would say!

Last Edited by boscomantico at 14 Nov 19:23
Mainz (EDFZ) & Egelsbach (EDFE), Germany

The S turn at the end is nice.

EGTK Oxford

PBN RNP 0.3…?

PBN

Last Edited by Vref at 14 Nov 20:10
EBST

RF legs are just the GPS equivalent of DME arcs right?

There are some similarities, they are both a curved path. The DME arc construction is relatively crude and the lowest DME arc is 7 NM. The RF leg can have a radius as low as 3 NM. The smaller radius may require speed limitations to keep the bank angle within acceptable limits. The DME arc has obstacle protection the same width as an airway, +/- 4 NM either side of center with another 2 NM of secondary area on each side of the main protected area. The DME arc is based on keeping the aircraft within a DME distance +/- of the centerline and doesn’t usually have CDI guidance, although some GPS units provide it. The RNP value in the terminal area is normally 1 up to the final approach segment and .3 NM on the final. The protected area for the RNP is twice the RNP specification without a secondary area. The DME arc only supports turns around the center of the facility whereas the RF is around an arbitrary point radius equidistant from the two waypoints that start and end the arc. They can be joined directly with RF legs in opposite directions or different radius to define any path within the specification. Usually they are flown using roll steering autopilot with a constant bank angle or the guidance from a flight director although the CDI can be programmed to follow displacement from the RF leg arc.

KUZA, United States

I wonder why they banned private pilots flying these. They could have stipulated an autopilot, for example.

Currently you can get PRNAV approval for a C150 with a GNS430, no autopilot and AFAIK no HSI. It’s a joke…

Administrator
Shoreham EGKA, United Kingdom

Like it.

QuoteCurrently you can get PRNAV approval for a C150 with a GNS430, no autopilot and AFAIK no HSI. It’s a joke…

Not in the US you can’t.

EGTK Oxford

Reason?

Administrator
Shoreham EGKA, United Kingdom

To get a PRNAV LoA you need to show that the avionics and aircraft are approved for PRNAV. A 430 in a C152 can’t possibly be can it?

EGTK Oxford

And no WAAS / SBAS in sight!

YPJT, United Arab Emirates
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