JetBlue Pilot Assists Cirrus Pilot on an ILS

I haven't flown with a Garmin for a number of years. Can you join the ILS final in LNAV then change to VLOC and track the localizer prior to the final-approach segment?
 
I haven't flown with a Garmin for a number of years. Can you join the ILS final in LNAV then change to VLOC and track the localizer prior to the final-approach segment?
A Garmin 400 series lets you switch to VLOC whenever you like, although I think I was told by an instructor that you're supposed to switch to VLOC as soon as you receive a vector to intercept the localizer. (This is consistent with Note 2 in AIM 1-2-3c, which prohibits using RNAV for lateral navigation on a localizer course.)
 
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My wife's IFR instructor called that the "pass/fail" button. Get that wrong and you fail the checkride.

They call that button the $400 button around here. Forget to push it on the checkride and you'll spend that for a retest.

On a related topic, I've never seen a Garmin 430/530 that was set up to automatically switch from GPS to VLOC, as was mentioned earlier. It must be rare for people to enable that feature.
 
A Garmin 400 series lets you switch to VLOC whenever you like, although I think I was told by an instructor that you're supposed to switch to VLOC as soon as you receive a vector to intercept the localizer. (This is consistent with Note 2 in AIM 1-2-3c, which prohibits using RNAV for lateral navigation on a localizer course.)
That is only "without reference to raw localizer data". Is the LOC course not displayed before VLOC is selected?
 
That is only "without reference to raw localizer data". Is the LOC course not displayed before VLOC is selected?
You could tune in the localizer on a separate VOR receiver, but unless you do that, the "raw localizer data" will not be displayed without selecting VLOC.
 
A Garmin 400 series lets you switch to VLOC whenever you like, although I think I was told by an instructor that you're supposed to switch to VLOC as soon as you receive a vector to intercept the localizer. (This is consistent with Note 2 in AIM 1-2-3c, which prohibits using RNAV for lateral navigation on a localizer course.)
You're "supposed to" follow the LOC once you intercept. When you make the switch is a matter of technique. One option is to have your panel GPS set for automatic switching. I do that but, preferring to do it manually, I do the switch on that final instruction to intercept the localizer when being vectored.
 
As I’m the JBLU pilot who helped and just wanted to explain more of the situation.
When we checked in with Jax approach we heard (can listen to the interactions with the Cirrus pilot on liveatc) where he said to the controller “he was a little rusty on the localizer and was wondering he he could help”. The controller said he could only give vectors and he wasn’t a pilot so really couldn’t help.
After he was pulled off the approach after having issues with intercepting the loc, he was sent back around and was given the opportunity to get things ready for the approach and to let Jax know when he was ready to try again. He was cleared for the approach and sent to tower. We were right behind him and could tell something was up and offered my help as a current Cirrus pilot and an ex CSIP, if anything was needed. The Jax controller then asked me if there was any reason why the Cirrus would be 900’ below the FAF as he crossed it at 1000’ and continued to descend. I said no and shouldn’t be anywhere near that altitude and was probably complacency. Again told the Jax app controller to pass along that I would be happy to help if he goes missed. We get cleared for the approach and sent to tower right behind the Cirrus.

Once on tower I told the controller I was willing to help once we got on the ground since we had to do our jobs first. This is where you can hear me say to the Cirrus “just remember fly the airplane”. As an instructor where a student is already stressed, just positive comments and keeping it simple can mean a lot. Once on the ground, I asked the pilot if he was flying an Avidyne or Garmin Cirrus. He said Avidyne, and tried to explain how to couple the approach but he brushed it off to want to fly green needles and hand fly it. Already knowing he had issues with capturing the GS and saying he had issues with the autopilot capturing altitudes, I offered proper speeds and power settings that would allow a proper descent rate. I also asked the pilot to double check the loc freq and course which he said he checked. With the help of the controller he called out the marker and the pilot proceeded with his descent. I questioned the pilot on his speed which he said was 110 kts, corrected him saying it should be 90-100 kts and even earlier said if he should be at 50%flaps. Forget when I asked how much fuel he had left which he responded back with 9 gallons remaining and he had to get on the ground. I tried to be the calm instructor voice but didn’t want to overload the freq since he was already stressed enough. Once he declared the runway was in sight I said on he freq “ remember it’s not over till you are on the ground”.
I’m no way saying i am or should be considered a hero or something but feel I helped the pilot safely get on the ground. Someone on the radio offered Orlando had better weather than Jax but with say 9 gal of fuel he wouldn’t have made it and his options became limited which could have been a caps deployment of worse if the weather got worse.
Once he landed and parked at sheltair he copied down my phone number and offered him to call me anytime if he wanted to talk.

Again, even after I finished the night I thought of ways I could have said or done things differently but in the end the pilot got on the ground safely and that’s all that really matter in the end.

Thanks for looking out for another pilot. As a GA pilot, I appreciate that the professional pilots will do what they can to provide assistance.
 
A Garmin 400 series lets you switch to VLOC whenever you like, although I think I was told by an instructor that you're supposed to switch to VLOC as soon as you receive a vector to intercept the localizer. (This is consistent with Note 2 in AIM 1-2-3c, which prohibits using RNAV for lateral navigation on a localizer course.)
Let's say your on your own navigation on this ILS from over SEAVU. When would you switch from LNAV to the localizer?
 

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Let's say your on your own navigation on this ILS from over SEAVU. When would you switch from LNAV to the localizer?
I’d switch on a Tuesday. That one intercepts a long way out. Knowing what some localizers do at half that distance I have to ask how straight that localizer really is. Since it’s California the question is probably pointless.
 
It was an ILS approach so there’s no need to dive and drive.
What's the current consensus on this? I've flown with a few different IR rated pilots and instructors recently and there seem to be two schools. One believes that with the GPS counting down the time you are better off planning a smooth even descent to pass your fixes at or above the minimum altitude. The idea is that a.) with tech it is pretty easy to do mental math "okay I need about 700fpm" and b.) that diving and driving gives you more time and opportunity to accidentally drift below the min altitude.

The other school is that it is easy to just drop down at 1,000 fpm and then you don't have to worry about the descent profile until the next fix, at that point just maintain altitude and track. I think I'm in the former camp, but don't have enough IR experience to be an ardent supporter of either

My wife's IFR instructor called that the "pass/fail" button. Get that wrong and you fail the checkride.
Pretty much what my instructor said as well during our initial instrument lessons. On the GTN plane we fly it *should* switch to VLOC on its own but the way we treat it is to assume it won't switch on its own so we always babysit the GPS/VLOC modes
 
What's the current consensus on this? I've flown with a few different IR rated pilots and instructors recently and there seem to be two schools. One believes that with the GPS counting down the time you are better off planning a smooth even descent to pass your fixes at or above the minimum altitude. The idea is that a.) with tech it is pretty easy to do mental math "okay I need about 700fpm" and b.) that diving and driving gives you more time and opportunity to accidentally drift below the min altitude.

The other school is that it is easy to just drop down at 1,000 fpm and then you don't have to worry about the descent profile until the next fix, at that point just maintain altitude and track. I think I'm in the former camp, but don't have enough IR experience to be an ardent supporter of either
I’ve always been a fan of the nice, smooth descent rather than chop and drop. Less power, changes, less leveling off. I don’t really like the roller coaster effect. Either way is fine, I just prefer to do/teach a constant descent rate. Nowadays, most planes equipped with GPS will tell you the vertical speed required to reach the next waypoint and pilots don’t even have to do mental math.
 
What's the current consensus on this? I've flown with a few different IR rated pilots and instructors recently and there seem to be two schools. One believes that with the GPS counting down the time you are better off planning a smooth even descent to pass your fixes at or above the minimum altitude. The idea is that a.) with tech it is pretty easy to do mental math "okay I need about 700fpm" and b.) that diving and driving gives you more time and opportunity to accidentally drift below the min altitude.

There is no consensus. I think it depends on the plane, the pilot and the approach.
For example, in the Cirrus SR20, dive and drive was really easy to pull off and gave you a lot more time when at MDA to look for the runway in margin conditions. However, in the Aerostar, with an approach speed 50% higher, and a lot more happening, a constant descent angle was much more preferable.

Tim
 
I’ve always been a fan of the nice, smooth descent rather than chop and drop. Less power, changes, less leveling off. I don’t really like the roller coaster effect.
Thanks, that's the way my current instructor has been teaching me, but the two other pilots I flew with recently both were big proponents of the "dive and drive." I agree though, I think you are more stabilized and in control of the plane flying it down steady. It's really not hard to do a quick mental math, or like you said, most modern GPS will give you the vertical speed anyway

I think it depends on the plane, the pilot and the approach.
For example, in the Cirrus SR20, dive and drive was really easy to pull off and gave you a lot more time when at MDA to look for the runway in margin conditions. However, in the Aerostar, with an approach speed 50% higher, and a lot more happening, a constant descent angle was much more preferable.
Thanks, in my case we're talking 1970s spam cans with the occasional Cirrus mixed in (when budget permits). That's a good point on getting more time at the MDA
 
I’d switch on a Tuesday. That one intercepts a long way out. Knowing what some localizers do at half that distance I have to ask how straight that localizer really is. Since it’s California the question is probably pointless.
Fortunately, California doesn't design IFPs.
 
Let's say your on your own navigation on this ILS from over SEAVU. When would you switch from LNAV to the localizer?
Since it's own nav rather than a vector, the advice that (I think) the instructor gave would not apply. I would wait until I was on the final approach course and close enough to receive a stable unflagged localizer signal. (If there is some guidance about where to switch, I would love to hear it.)
 
Since it's own nav rather than a vector, the advice that (I think) the instructor gave would not apply. I would wait until I was on the final approach course and close enough to receive a stable unflagged localizer signal. (If there is some guidance about where to switch, I would love to hear it.)
The newer Garmin gear switches when the PFAF becomes the active waypoint (provided the VORLOC is on the ILS frequency and the approach mode is selected.) This would be passing SHELL. SHELL is the intermediate fix so prior to that point the approach course has Victor airway widths.
 
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The newer Garmin gear switches when the PFAF becomes the active waypoint (provided the VORLOC is on the ILS frequency and the approach mode is selected.) This would be passing SHELL. SHELL is the intermediate fix so prior to that point the approach course has Victor airway widths.

That makes sense; I guess four nm each side of course ought to be enough even for me! However Garmin's autoswitching algorithm seems to be at odds with note 2 of AIM 1-2-3c, which says the following about RNAV substitution, without any mention of how far out on the localizer you are:

"2. These operations do not include lateral navigation on
localizer−based courses (including localizer back−course
guidance) without reference to raw localizer data.
"​
 
That makes sense; I guess four nm each side of course ought to be enough even for me! However Garmin's autoswitching algorithm seems to be at odds with note 2 of AIM 1-2-3c, which says the following about RNAV substitution, without any mention of how far out on the localizer you are:

"2. These operations do not include lateral navigation on
localizer−based courses (including localizer back−course
guidance) without reference to raw localizer data.
"​
I can't find the reference offhand, but my impression was that the LOC and GS were only required for the final approach segment.
 
I can't find the reference offhand, but my impression was that the LOC and GS were only required for the final approach segment.
That's what I recall from the info on when and how GPS can be substituted for other approach instruments. The FAF is the defining point for when radio nav must be used on approaches that aren't RNAV. Various reasons for that I guess and flight check is prolly a big one.
 
I can't find the reference offhand, but my impression was that the LOC and GS were only required for the final approach segment.

I thought that too, but it was a mistake. It's the same reference—AIM 1-2-3(c), or AC90-108, which have the same information: you may NOT use RNAV in lieu of a conventional NAVAID during the final approach segment. You also may NOT use RNAV in lieu of a localizer-based course at any time without reference to raw localizer data.
 
I can't find the reference offhand, but my impression was that the LOC and GS were only required for the final approach segment.
You might be thinking of Note 4 in the same section:

"4. Pilots may not substitute for the NAVAID (for example,
a VOR or NDB) providing lateral guidance for the final
approach segment. This restriction does not refer to
instrument approach procedures with “or GPS” in the title
when using GPS or WAAS. These allowances do not apply
to procedures that are identified as not authorized (NA)
without exception by a NOTAM, as other conditions may
still exist and result in a procedure not being available. For
example, these allowances do not apply to a procedure
associated with an expired or unsatisfactory flight
inspection, or is based upon a recently decommissioned
NAVAID."

Note 2 and note 4 look to me to be independent of each other, which implies that note 4 would not override note 2.

These notes are on page 1-2-7 of the October 12, 2017 edition of the AIM.
 
That's what I recall from the info on when and how GPS can be substituted for other approach instruments. The FAF is the defining point for when radio nav must be used on approaches that aren't RNAV. Various reasons for that I guess and flight check is prolly a big one.
I can tell you that the FAA issued a bulletin a few years ago advising airline pilots flying the ILS approaches from the east to use LNAV and Baro VNAV to assure not busting the step-down fixes on a hot day. All the airline equipment does the same as the newer Garmin equipment does: remains in LNAV until crossing the fix prior to the PFAF.
 
Sounds like the FAA's right hand doesn't know what the left hand is doing.
 
You might be thinking of Note 4 in the same section:

"4. Pilots may not substitute for the NAVAID (for example,
a VOR or NDB) providing lateral guidance for the final
approach segment. This restriction does not refer to
instrument approach procedures with “or GPS” in the title
when using GPS or WAAS. These allowances do not apply
to procedures that are identified as not authorized (NA)
without exception by a NOTAM, as other conditions may
still exist and result in a procedure not being available. For
example, these allowances do not apply to a procedure
associated with an expired or unsatisfactory flight
inspection, or is based upon a recently decommissioned
NAVAID."

Note 2 and note 4 look to me to be independent of each other, which implies that note 4 would not override note 2.

These notes are on page 1-2-7 of the October 12, 2017 edition of the AIM.
If you find it easier to navigate the AIM by paragraph instead of page number it's 1-2-3 c.
 
I can tell you that the FAA issued a bulletin a few years ago advising airline pilots flying the ILS approaches from the east to use LNAV and Baro VNAV to assure not busting the step-down fixes on a hot day. All the airline equipment does the same as the newer Garmin equipment does: remains in LNAV until crossing the fix prior to the PFAF.
More on that in AIM 5-4-5 b., note 2.
 
I thought that too, but it was a mistake. It's the same reference—AIM 1-2-3(c), or AC90-108, which have the same information: you may NOT use RNAV in lieu of a conventional NAVAID during the final approach segment. You also may NOT use RNAV in lieu of a localizer-based course at any time without reference to raw localizer data.
The recent Garmin equipment I am familiar with will show a shadow LOC and GS while tracking an ILS outside the fix prior to the PFAF. So, that would certainly meet the monitoring of raw data requirement. The monitoring requirement is absurd, though, on an ILS outside the IF. The protected airspace is equivalent to RNAV-2, which is the same as a T or Q route. But, the FAA has been known on occasion to be absurd. o_O
 
Let's say your on your own navigation on this ILS from over SEAVU. When would you switch from LNAV to the localizer?
I think I'd probably do it well before FOGLA where it becomes required. I probably wouldn't do it between SEAVU and LYCOM, and just have a peek at my source for 'raw localizer data.'
 
The recent Garmin equipment I am familiar with will show a shadow LOC and GS while tracking an ILS outside the fix prior to the PFAF. So, that would certainly meet the monitoring of raw data requirement. The monitoring requirement is absurd, though, on an ILS outside the IF. The protected airspace is equivalent to RNAV-2, which is the same as a T or Q route. But, the FAA has been known on occasion to be absurd. o_O
At least they put out that bulletin you mentioned in post #110 that pretty much says 'we know the letter of the law says use the localizer but go ahead and use LNAV anyway.' I'm wondering how wide the localizer is out there at LYCOM. It's 37 miles out from the antennae which is at the far end of a 2 mile long runway. It's supposed to be 700 feet wide at the runway threshold. I don't know how to do the trigonometry.
 
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