gnss - How much can Flight Level and GPS altitude differ?
Oct 11, 2025 · It depends primarily on the temperature of the air below the aircraft and to a smaller degree on the local barometric pressure. At indicated FL410 the GPS altitude could be …
What does it mean for a GPS PRN to be unserviceable?
There is a current NOTAM: !GPS 02/035 GPS Navigation PRN 28 unserviceable Feb 21, 2023 2020Z to May 31, 2023 2359Z What exactly does it mean for a GPS PRN to be unserviceable, …
gnss - Why do planes need line of sight for GPS to work?
Sep 10, 2015 · Why is the below true when mobile devices such as mobile phones and designer watches with emergency beacons work without Line of sight? Most commercial aircraft …
gnss - Data for mapping a past flight? - Aviation Stack Exchange
Nov 29, 2023 · Is there a website that shows past flight tracks of a few days back? tells how to use FlightAware to see a past flight on a map. But is there any public source of …
What does a DME indicator do in HOLD or RNAV mode?
Dec 3, 2021 · I found this DME indicator on the Cessna 210. Its mode switch has four positions - NAV1, NAV2, RNAV and HOLD. NAV1 and 2 are clear - it uses the NAV1 and 2 freq …
gnss - Garmin 695/696 joystick removal - Aviation Stack Exchange
Jul 19, 2024 · I have a Garmin 696 with a faulty joystick. I have a parts unit that I'd like to swap the joystick with, however upon disassembling the units, I can see how to disconnect the …
gnss - How do GLS avionics plot an entire accurate approach path ...
Jul 7, 2018 · The best reference is the ICAO GBAS Guide. Unfortunately, it doesn't have diagrams to help understand it. The Final Approach Segment (FAS) is a geodesic path to the …
gnss - Why do Computer Navigation Fixes still exist now that GPS ...
May 26, 2017 · A CNF is a point that defines a navigation track for a GPS, but why is it used when you there are GPS waypoints that are created to define a track?
gnss - Why are SBAS-equipped planes exempt from the preflight ...
Mar 13, 2021 · My question stems from this other question: Why is training regarding the loss of RAIM given so much more emphasis than training regarding the loss of SBAS? Two answers …
gnss - What is the difference between SBAS and SBAS PA mode …
Jul 17, 2023 · 5 We have a Collins FMS, and in the GNSS control page it tells you what mode it is operating in. In the instance that I checked it, it said " SBAS PA". The flight manual said that it …