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Is it time to forgo VHF navigation?

Yes this expert says ILS is more accurate than GPS even with WAAS... ILS it's called a "Precision Approach" for a reason. Do you have some data that shows ILS is inaccurate? Rhetorical. The answer is no. Also there all kinds of fail safe monitoring and backups and flags built into an ILS.

GPS based approaches generally are not a Precision approach and have much higher minimums including KMRY 520-1 1/2....... ILS at KMRY is 200- 1/2, lower mins by 320 and 1 mile. Why ILS is more accurate. Want to get in? ILS everytime. The higher min to 10R for ILS is only of you cant miss and climb 265 ft/min per NM to 1360 feet. An RV can exceed that x4 at least. Even the # mins are lower than the GPS approach.

Bottom line thousands of airliners world wide are flying ILS to every runway with an ILS (even in VFR condtions). Most major airports served by airlines have an ILS approach. The lowest mins still belong to Cat 1 ILS not GPS. ILS Cat 2 and 3 of course is even lower.

LPV approaches with WAAS/GPS are similar to an ILS, but even though LPV approaches have vertical guidance, they're not considered precision approaches at this time. Forget GPS autoland anytime soon if ever. GPS is awsome and GPS only IFR is a resonable choice. My argument with you is that the ILS is highly accurate and reliable, still rules at this time and likely for decades to come, before commercial aircraft stop using the ILS.

You other argument is you should not fly an ILS to.mins and double mins if you are not current (for discussion purposes not current = legal but not proficient). I agree, but then by that logic you should not fly GPS RNAV approaches to mins if not current. Even if you double the ILS min it is still lower than the RNAV approach at KMRY! Ha ha.
Ouch. Nice takedown. I appreciate your willingness and others as well to dispell the disinformation.
 
1) No ILS should be unstable. They are flight test by the FAA to high standards. There's something seriously wrong with the ILS if it's like a rollercoaster. it should be reported. If it doesn't meet strict standards then it would be decommissioned.

I suspect he?s referring to when an aircraft penetrates the ILS critical area.
 
1) No ILS should be unstable. They are flight test by the FAA to high standards. There's something seriously wrong with the ILS if it's like a rollercoaster. it should be reported. If it doesn't meet strict standards then it would be decommissioned.

2) You're making straw man arguments and off the point. Nobody's saying anything bad about GPS approaches they're fantastic, and if your mission calls for it and you can afford it, get IFR GPS. Your needless bash of ILS approaches as inferior approach is just pointless. GPS rnav approaches provides very good IAP's to airports that didn't have any ILS. However the fact is as I stated I'll less is a higher Precision approach than just about any GPS approach to date. I mean it's just a fact.

1. Here at LVK, for years the ILS had a note: ?No autopilot coupled approaches below 1800??. It was the rollercoaster issue. The FAA flight checked it, and sometimes the note would go away. Then after another check it came back. It was better than having no approach at all, pre-gps.
2. I think the ?bashing? of ILS is just the simple fact that the typical destination airport for an RV doesn?t have an ILS. And, to be fair, many of the airports that now have LPV approaches (which never had an ILS) do not have the approach light system needed to get 200? - 1/2. If you look at airports with an ALS, many of them now have an LPV to 200? - 1/2.And while, in principle, I think it?s possible to get a cat II authorization for an RV and its pilot, I?ve never heard of it actually being done.
 
Yes

It is possible, however, there are a lot of hoops to jump through...and continuing qualification to deal with...
 
MGL?

I'm curious about whether anyone has tried the MGL N16 nav radio? Might be a good option at a very low cost and using very little panel space for GPS backup. I hung a VAL INS429 under my panel and put in a used DME. I love having the capability of flying ILS approaches into my home airport in Baton Rouge. It comes in handy when my instructor wants to see me fly an ILS approach. John
 
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Maybe a little off topic but I do not know much about the all in one glass panels. Do you still get a usable magnetic heading that you can navigate by if you lose GPS signal? I remember some discussions as to if an actual whisky compass was required or not. I proudly have one as well as an old school IFR panel.
 
Maybe a little off topic but I do not know much about the all in one glass panels. Do you still get a usable magnetic heading that you can navigate by if you lose GPS signal? I remember some discussions as to if an actual whisky compass was required or not. I proudly have one as well as an old school IFR panel.

The short answer is that GPS provides GROUND TRACK information. Magnetic heading comes into play if the EFIS system has installed an element to sense the earth's magnetic field - a magnetometer.

If the EFIS has a magnetometer then you are going to get magnetic heading information irrespective of the availability of any GPS input.

Conversely, with many EFIS devices, if the magnetometer fails and valid GPS navigation data is present, the EFIS may default to displaying GPS-derived ground track.

Of note, those of us building in Canada still seem to have to live with the age-old requirement to install a whiskey compass, even if we have three EFIS installed, each with its own magnetometer and each backed up with its own battery. Old habits die hard in the regulatory world!
 
GPS replacement

Just noticed a planned GPS outage by the Navy for southeast NC,SC GA. Since they did away with LORAN, I would love to see a small light weight IRS (inertial reference system) for light airplanes. Then we wouldn?t be dependent on any outside system for navigation. Airlines and biz jet have them, I suppose cost is the issue. Would work at sub $10,000 though.
 
Ask the locals who fly lots of IMC

I think one thing that may be being overlooked is what the reliability of GPS signals is, from a local perspective.

I have talked to numerous folks who regularly fly from Livermore to Southern California who have had repeated GPS outages, both scheduled, notamed and unscheduled. If they had been landing IMC in the areas of the outages they would have needed VHF capability.

I would suggest that you look carefully at your local situation to help answer the original question. I don?t doubt at all that there are many folks who never missed having a VHF receiver who fly IMC a lot, but there may be a different answer for someone else?s situation and location. If you?re needing to fly IMC into an area that has lot?s of military activity, you may want to do some more detailed research.

This is coming from someone with no instrument rating but starting back into the training again, after an ?unscheduled? panel upgrade that took 18 months!
 
Hooray for Rocket Bob.

Do not mess with Rocket Bob. That guy knows very well whereof he speaks. Need more like him.
 
Do not mess with Rocket Bob. That guy knows very well whereof he speaks. Need more like him.

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VAL INS429

I hung a VAL INS429 on the bottom edge of my panel for VOR/ILS capability and bought a used King DME for backup for my Garmin 400W. If I lose my EFIS or GPS, I can get down with the "all-in-one" VAL unit and my Garmin G4 PFD. I really like having the backup. I use a Sporty's SP400 on a RAM mount to do in flight VOR checks. The VAL and the DME were very easy to install and relatively inexpensive. John
 
I hung a VAL INS429 on the bottom edge of my panel for VOR/ILS capability and bought a used King DME for backup for my Garmin 400W. If I lose my EFIS or GPS, I can get down with the "all-in-one" VAL unit and my Garmin G4 PFD. I really like having the backup. I use a Sporty's SP400 on a RAM mount to do in flight VOR checks. The VAL and the DME were very easy to install and relatively inexpensive. John

Amen on the VAL INS-429. I'm installing one right now in my panel. Even if I can't receive it with the VAL I can always file direct to a VOR 300 miles away that coincides with the GPS location I want to get to and then just let the autopilot fly the Garmin 496 while monitoring it on the iPad moving map. It's just like having an IFR GPS but at 1/4 of the price.
 
With the world rapidly moving to a GPS Anyone else been pondering this? David
Anyone pondering? Yes everyone. This topic is beat to death from time to time. Let the flogging began. Ha ha. :) Short answer is what is your mission, but for VFR sport pilot GPS is fine. IFR operations IFR TSO GPS and current data base is also fine.

ILS is still #1 approach world wide with the lowest minimums, no debate. So there is that. Otherwise VOR en-route and VOR approaches have been almost completely supplanted by GPS... ADF/NDB is gone the way of A-N ranges.

Can GPS go down? Oh yes it happened to me once. However if VFR it is not a big deal.
 
Yes, it's time to let it go. "let it go, let it go" - sing along with me.

I haven't experienced an actual GPS outage, meaning RAIM failure, since 2007. Only issues I've seen, and I fly a lot, have been related to testing, where the "STOP BUZZER" term to ATC works very well.
 
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GPS outage

Just flew through a GPS outage a couple days ago. Military jamming exercise. I'd prefer a GPS navigator that included an ILS receiver and VOR in the box. Doesn't take up any more space and you'd at least have something if you were in an area with GPS out.
 
Thinking about adding another gps antenna for redundancy. Otherwise I like my system.
2 classic skyviews, AP, dual adhars, sl30. Gtx327 /gdl82 .
 
This is the GPS unreliable notam for last night from BWI to PHX.

It's common to see but not usually this bad.

 
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So there's the legal aspects to this, which is clear.

There's also the aspect of being wise. So if your nice GPS unit quits working while in the soup being radar vectored, because things fail, which one has to assume will eventually happen, I certainly would feel more comfortable with a separate VOR/ILS.

I almost went GPS only, but a friend pointed out the option of needing ILS for an IFR alternate led me to install the antenna for my 650. A couple of days ago, on and IFR plan descending and headed for the RNAV 31 FAF and the 650 GPS started winking, then out and blanked out the G3X map too. So, AP is heading/alt hold only. I did have FF up on the iPad and used that to track to the FAF. The overcast luckily cleared enroute and became VMC actual but it could have just as easily remained IFR. ILS and vectors would have been my only option.

It is very good (possibly lifesaving) to have an option, and I will be practicing procedures under the hood for the next GPS failure.

Edit-PS - My GA35 and GA57 antenna apparently are too close together and GA35 blanked out reception for the 57. My so called redundancy was tied to the root failure!! Separate your antenna! Garmin can say how far.
 
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Anyone pondering? Yes everyone. This topic is beat to death from time to time. Let the flogging began. Ha ha. :) Short answer is what is your mission, but for VFR sport pilot GPS is fine. IFR operations IFR TSO GPS and current data base is also fine.

ILS is still #1 approach world wide with the lowest minimums, no debate. So there is that. Otherwise VOR en-route and VOR approaches have been almost completely supplanted by GPS... ADF/NDB is gone the way of A-N ranges.

Can GPS go down? Oh yes it happened to me once. However if VFR it is not a big deal.

Slightly off topic: Early evolution of airway navigation...from railroad tracks, to bonfires, to lighted airways, to A-N ranges, to VOR, etc. Even then there was the occasional bonfire going out or lighted airway beacon going T/U. The only dependable navaid was the paper chart unless it blew out of the cockpit.

https://airandspace.si.edu/stories/editorial/guiding-light-airway-beacon-tower
 
Slightly off topic: Early evolution of airway navigation...from railroad tracks, to bonfires, to lighted airways, to A-N ranges, to VOR, etc. Even then there was the occasional bonfire going out or lighted airway beacon going T/U. The only dependable navaid was the paper chart unless it blew out of the cockpit.

https://airandspace.si.edu/stories/editorial/guiding-light-airway-beacon-tower
COOL! Oh yes. Post WWI Pre WWII it was IFR "I follow Roads" or light beacons, akin to ship light houses. They flew light to light at night. Day time they read the towns name on Water towers, aka "Pilotage". I still look for the beacon and runway approach lights at night. 10 miles away I'd click on the airports lights and see the glow in the distance. It's fun to turn off the GPS.

My Dad WWII era Pilot, said to me as a kid, "Son in my day all we had was a Jelly Jar Compass and Map" when explaining the VOR to me when he took me flying in the AeroClubs Cherokee, aka Dead Reckoning. I got my Private Pilot Mid 80's, LORAN was around in a few rentals, and GPS was not out quite in GA planes, at least in mass. I really enjoyed pilotage and dead reckoning. Big satisfaction when you arrived over your fix on time.

"Pilotage is defined in the FAA's Pilot's Handbook as using landmarks or checkpoints, often in conjunction with Dead Reckoning, using last known fix and predicting next by knowing airspeed and heading and estimating (Deducting) ground speed and track based on wind drift. The Dead is short for deduction. Deduction Reckoning is not as catchy. I guess you are DEAD if you don't navigate properly.

Fan fact INS or (Inertial Nav System) or now IRU (Inertial Ref Unit) on Airliners and Military planes, provides accurate Nav position without any Nav Aids outside the plane of any kind and therefore is dead Reckoning!!! The INS/IRU was simply told where it's on the ground, before moving (Initialized). From then on internal gyros and accelerometers keeps track of current position by which way you moved for how long and adds it up. The INS electric mechanical Gyros were later replaced by laser rings that measures the time difference it takes light to travel due to rotational movement in three planes (degrees of freedom). The FMC (Flt Management Computer) or NAV computer uses this position from IRU with a database to give accurate position on a map display. They early INS only gave raw data LAT/LONG/GND SPD and TRK, no moving map display.

However over time an INS or IRU will drift, lose accuracy and need updating by a Terrestrial Nav source (DME-DME for example) or GPS Nav input today. Way before GPS in early days of INS, the INS drifted more than today's solid state IRU's. The early INS required Pilots to manually check for accuracy before "coasting out" or going over the water portion of the trip. The cross checked they used land based NAV Aids or even pilotage to verify the IRU was working and accurate. If over the water for any length of time they needed to check position of INS using Celestial navigation by a sextant. This combo of INS and Celestial Nav was used in Apollo missions to get to moon. If you know the night sky you can use stars to navigate just by looking at them. (Pretty rough guess but point is that was #1 Nav aid in ancient times.)

Decades before GPS the SR71 had ASTO-NAV which was like a Star Wars R2-D2. It took star sightings automatically and computed position. It was cutting edge... Because of the SR71's speed only a machine could calculate accurate position. I believe variations are still used and would be critical in times of GPS black out.

https://www.thedrive.com/the-war-zo...ning-future-fights-in-gps-denied-environments

Celestial Nav goes back to rudimentary methods almost a millennium ago, middle ages. Even the Bible talks of star Nav. In "modern times" it goes back several centuries. The Sextant was invented Mid 1700's. Jump forward 200 years the first GPS prototype satellite was launched 1974. It soon failed, but a constellation of 11 GPS satellites launched by 1977. Then in 1985, the first 11-satellite GPS Block I constellation was in orbit which brought GPS for the masses. They are launching Block 3 series satellites now. They will be less prone to jamming and interference. Amazing time we live in.
 
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