VOR Check

[RussR]

ILS most times has a lower DH & vis than any GPS procedure.

At least to me, "most" means, well, "most". At a minimum I guess it could mean 51% or more, but in my mind it's probably like 75% or more. And while I have no way to easily back this up, I don't think that "most" ILSes have lower minimums than an LPV to the same runway.

In my experience, at most airports with an ILS and an LPV to the same runway, the minimums are identical. The exceptions will be those where the last full amendment to the procedure was prior to about 10 years or so ago, when the criteria for ILS and LPV finals was largely harmonized. The other possible exception is where the missed approach designs differ significantly, again due to criteria that changed 10 or so years ago.

It used to be the case that LPVs were limited to 250 HAT, and with the ILS at 200 HAT, that's probably the difference you recall. But it hasn't been that way for quite a while, as LPVs were next allowed to go to 200 HAT if there was an ILS to the same runway, and then (as it is now), LPVs can be 200 HAT without any underlying ILS as long as the obstacle criteria is met.

Some of this is regional, as mountainous terrain and other obstacles can cause the minimums to be different. But a quick check of my state (Oklahoma) shows 18 runways at public-use airports with ILS procedures. All of them have RNAV procedures with LPV minimums, and the minimums are the same as the corresponding ILS on all but 2 of them.

 

[flyingron]

You do not need a VOR check to use the ILS (unless the approach has some other fix that needs a VOR). The VOR check does nothing whatsoever to test the LOC signal reception/accuracy. It's an entirely different kind of modulation, altogether.

 

[MauleSkinner]

It’s an entirely different kind of modulation.

 

[Salty]

You do not need a VOR check to use the ILS (unless the approach has some other fix that needs a VOR). The VOR check does nothing whatsoever to test the LOC signal reception/accuracy. It's an entirely different kind of modulation, altogether.

it's an entirely different kind of modulation

 

[Palmpilot]

It's an entirely different kind of modulation.

 

[Rgbeard]

Okay, I can see that. Not sure I'd call it "better", but maybe "more useful for most operations" I guess. I do suppose that "more useful" and "better" are basically synonyms, so I'm able to be swayed on this one.

But if the weather is 600 overcast and 2 1/2 sm of visibility, or lower, it's pretty clear which approach is the only option.

Yessir. Capt. Obvious did a low fly-by on that one. Thanks!

If the weather is below minimums for one approach, and there’s another with lower minimums, one will need to switch. Got it.

Fortunately, at SDM this means the VOR approach is highly useful during most times. Excepting most early morning hours.

 

[Archer Jack]

Just finished mowing the back yard and came inside to cool off. It's only 1000 and already 92. So I decided to open up my good old POA for some excitement. Wow! This has really got my heart rate up! Can't wait to hear if +/- is okay. Cheers

 

[Plano Pilot]

Yessir. Capt. Obvious did a low fly-by on that one. Thanks!

If the weather is below minimums for one approach, and there’s another with lower minimums, one will need to switch. Got it.

Fortunately, at SDM this means the VOR approach is highly useful during most times. Excepting most early morning hours.

I have done a similar thing several times. If the WX is good enough, shoot the approach from the direction you are coming in from and then either circle or land with a slight tailwind. Saves time, fuel and money.

 

[Palmpilot]

Yessir. Capt. Obvious did a low fly-by on that one. Thanks!

If the weather is below minimums for one approach, and there’s another with lower minimums, one will need to switch. Got it.

Fortunately, at SDM this means the VOR approach is highly useful during most times. Excepting most early morning hours.

Would it be too much trouble to land at SEE or MYF every 30 days to use a VOT?

 

[asicer]

Is there a technical reason a VOT can't be used while airborne? I noticed that the FAA allows it over/near OKC and Meacham but nowhere else.

 

[Rgbeard]

Would it be too much trouble to land at SEE or MYF every 30 days to use a VOT?

Yes.

 

[Pinecone]

Yeah, stop navigating with VORs.

That seems to be the answer

 

[40YearDream]

Hey, no problem with those disappearing VORs: AIM 1-1-3.f has the solution for when GPS is interrupted - "Aircraft that carry DME/DME equipment can also use RNAV which provides a backup to continue flying PBN during a GNSS disruption." Anybody ever seen an airplane equipped with 'DME/DME' ? (and that doesn't mean having 2 DME units, as unlikely as that'd be). Extra points if you know what 'DME/DME' is!

 

[flyingron]

RNAV that uses multiple DME stations. Sort of a prehistoric GPS.

 

[MauleSkinner]

Hey, no problem with those disappearing VORs: AIM 1-1-3.f has the solution for when GPS is interrupted - "Aircraft that carry DME/DME equipment can also use RNAV which provides a backup to continue flying PBN during a GNSS disruption." Anybody ever seen an airplane equipped with 'DME/DME' ? (and that doesn't mean having 2 DME units, as unlikely as that'd be). Extra points if you know what 'DME/DME' is!

Yes. A lot of FMSs can calculate position that way.

 

[RussR]

Hey, no problem with those disappearing VORs: AIM 1-1-3.f has the solution for when GPS is interrupted - "Aircraft that carry DME/DME equipment can also use RNAV which provides a backup to continue flying PBN during a GNSS disruption." Anybody ever seen an airplane equipped with 'DME/DME' ? (and that doesn't mean having 2 DME units, as unlikely as that'd be). Extra points if you know what 'DME/DME' is!

I was under the impression that most airliners and a lot of business jets have such a system, as one of the inputs into the FMS.

 

[Plano Pilot]

Our old FMS had GPS, DME/DME and LORAN. Each of the two DME units would track 3 stations.

 

[Maxnr]

Hey, no problem with those disappearing VORs: AIM 1-1-3.f has the solution for when GPS is interrupted - "Aircraft that carry DME/DME equipment can also use RNAV which provides a backup to continue flying PBN during a GNSS disruption." Anybody ever seen an airplane equipped with 'DME/DME' ? (and that doesn't mean having 2 DME units, as unlikely as that'd be). Extra points if you know what 'DME/DME' is!

I used to fly with a Dr/USN LCDR who had a J Bonanza. He had one of those units in his panel. He always offered the stick to me, but I was fascinated with the darned gadget. Couldn't leave it alone. I don't recall the name of it.
Along those lines, some research was done, wayback, using dual DME and dual VOR. Referred to as the Rho (DME), Theta (VOR) system. A finding was that a Theta-Theta system was less accurate. A six degree error at 30 miles equals a three mile error. A Rho-Rho system was more accurate because DME is accurate to 0.1 mile.