A better Straight-in VFR Approach

Jaybird180

Jaybird180

Final Approach
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Jaybird180
Recently, I was cleared by Class-D for a Straight-in to my destination. I've noticed what I consider a large amount of off-set when arriving to this particular airport. I believe there may be GPS testing nearby without NOTAMS often, as it can be off my several miles one day or reasonably accurate the next. This particular flight, the magenta line again will not take us to the airport. The airport happens to have crossing runways, so I expect the GPS to be plotted for the center of the airfield. But because of the aforementioned inaccuracy it will not.

About 15 miles out, I'm cleared for straight-in to a runway that will require much more than a 30* heading change. Foreflight's extended runway feature is makes visualizing runway centerline very easy, so I make the adjustment. After a few minutes, I'm certain of what I see out the windshield, in that I am now heading for the correct airport and the correct runway at about 9 miles out.

Since I have an approach certified GPS should I enter an approach into the GPS and then do a VTF type approach? Basically, that's what I did once my eyes were locked on target.
 
Not sure what a VTF type approach is. But I almost always back up the visual approach with a GPS or ILS approach. With my FMS I can also program in a visual approach that is similar to a GPS approach(but I get to manually pick the descent angle). No harm in using everything you have in the airplane to help you out. I've flown visuals where the sun was directly in my face and I needed the ILS to keep me on track cause I couldn't see anything.
 
If it's VFR I don't mess with the GPS approaches. I look out the window, find the airport, find the runway, land.
 
EdFred said:
If it's VFR I don't mess with the GPS approaches. I look out the window, find the airport, find the runway, land.
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This. Look outside. It's beautiful! No need to fiddle with the GPS. Although if you are unsure like you were, plugging in the GPS approach helps.
 
Jaybird180 said:
About 15 miles out, I'm cleared for straight-in to a runway that will require much more than a 30* heading change. Foreflight's extended runway feature is makes visualizing runway centerline very easy, so I make the adjustment. After a few minutes, I'm certain of what I see out the windshield, in that I am now heading for the correct airport and the correct runway at about 9 miles out.

Since I have an approach certified GPS should I enter an approach into the GPS and then do a VTF type approach? Basically, that's what I did once my eyes were locked on target.
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You said you were "cleared for a straight-in". Semantics here, but how were you "cleared"? I assume that was cleared to land and not cleared for some specific IFR approach.

Since you were VFR (?), the tower isn't terribly concerned about when you intercept the extended centerline. I'm not sure why you would want to activate some type of VTF (vectors to final) approach unless it's just for practice. But as long as you comply with the controller's wishes, you can navigate pretty much any way you wish.
 
write-stuff said:
You said you were "cleared for a straight-in". Semantics here, but how were you "cleared"? I assume that was cleared to land and not cleared for some specific IFR approach.
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I get this regularly in TX where almost all runway alignments are basically north/south. If you are coming from the north and landing on 17, they will clear you to land 17 straight in as opposed to 'make left traffic runway 17...'. Same for the inverse. One can always reject the straight in and I've done that before as well when landing at an airport I've never been to I prefer a standard traffic entry that complies with local pattern.

Oh and another vote for getting your head outside and forget the pink line stuff. If the runway is a bit 'over there' and not right under the nose then make the correction, land and deal with what the world says. Too much pink line fever these days.
 
VTF will work but I'd say your particular GPS probably shows an extended centerline for the airport on one of its maps. On my 480, I did a straight in the other day with no destination typed in simply by using the extended centerline. Helps when the airport is too far out to pick up visually.
 
Which airport? Are you sure that you're entering the airport ID and not a non co-located NAVAID with the same ID?
 
docmirror said:
I get this regularly in TX where almost all runway alignments are basically north/south. If you are coming from the north and landing on 17, they will clear you to land 17 straight in as opposed to 'make left traffic runway 17...'. Same for the inverse. One can always reject the straight in and I've done that before as well when landing at an airport I've never been to I prefer a standard traffic entry that complies with local pattern..
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I think the point was mainly that the pilot wasn't "cleared" for ANY type of approach while VFR and instead was directed to fly a straight-in and then "cleared" to land. As he said, semantics.

I'm more interested in the GPS misalignment the original poster speaks of. Something doesn't sound right here if the database point is not approximately on the airport grounds, and I doubt it's simply GPS testing without a NOTAM. I'd bet your GPS position is correct and either the database is messed up or you aren't selecting the right waypoint. Perhaps a VOR with similar name nearby?
 
dukeblue219 said:
I think the point was mainly that the pilot wasn't "cleared" for ANY type of approach while VFR and instead was directed to fly a straight-in and then "cleared" to land. As he said, semantics.
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Right, and I replied that the OP didn't state he was cleared for any kind of "approach" either:

Recently, I was cleared by Class-D for a Straight-in to my destination.

The OP was wondering if he should make a roll-your-own kind of approach using his fancy TV in the cockpit, nothing to do with what tower said to him.
 
ISaidRightTurns said:
Which airport? Are you sure that you're entering the airport ID and not a non co-located NAVAID with the same ID?
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I was looking to see if anyone thought of that before I mentioned the possibility. That was my first thought.
 
An easy trick I use with a GNS530 is with the airport as your waypoint, set the OBS to the runway number and that pretty much lines you up with the runway. :D
 
Jaybird180 said:
I believe there may be GPS testing nearby without NOTAMS often, as it can be off my several miles one day or reasonably accurate the next. This particular flight, the magenta line again will not take us to the airport.
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Where is this???
 
If your not sure,use fore flight with the extended runway center lines.
 
docmirror said:
Oh and another vote for getting your head outside and forget the pink line stuff. If the runway is a bit 'over there' and not right under the nose then make the correction, land and deal with what the world says. Too much pink line fever these days.
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I bet the big iron pilots who landed at the wrong airports wish they had a little more of that fever.
 
I don't see a problem with pulling up an approach VTF or otherwise. You're VFR and your ap is uncoupled, so who cares if you are on the pink line initially if the point is merely to confirm the correct runway centerline?

If you want vertical guidance while VFR (why?) then I think you should ask for a VFR practice approach from some convenient waypoint.

That said, I agree that ForeFlight's (and every other EFB's) extended rwy centerline feature is simpler if the pilot has it available.
 
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Jaybird180 said:
Recently, I was cleared by Class-D for a Straight-in to my destination. I've noticed what I consider a large amount of off-set when arriving to this particular airport. I believe there may be GPS testing nearby without NOTAMS often, as it can be off my several miles one day or reasonably accurate the next. This particular flight, the magenta line again will not take us to the airport. The airport happens to have crossing runways, so I expect the GPS to be plotted for the center of the airfield. But because of the aforementioned inaccuracy it will not.

About 15 miles out, I'm cleared for straight-in to a runway that will require much more than a 30* heading change. Foreflight's extended runway feature is makes visualizing runway centerline very easy, so I make the adjustment. After a few minutes, I'm certain of what I see out the windshield, in that I am now heading for the correct airport and the correct runway at about 9 miles out.

Since I have an approach certified GPS should I enter an approach into the GPS and then do a VTF type approach? Basically, that's what I did once my eyes were locked on target.
Click to expand...

If there is an error in your GPS position due to some kind of testing, how does Foreflight actually point to a runway where it actually is, and how would your GPS approach take you to the right place since they all rely on GPS?
 
seems like if the magenta line does not take you to the airport there is something happening - what if you were fly a GPS approach in the soup to an airport that is not there . . . meaning it does not appear once you complete the approach?

That's a pretty major issue whether a GPS outage is charted or not - did you perform a RAIM check? Enroute nav is so much broader in tolerance than RAIM for an approach but its not miles away as you state . ..

Where - and when exactly - so we can check raim.
 
docmirror said:
Oh and another vote for getting your head outside and forget the pink line stuff. If the runway is a bit 'over there' and not right under the nose then make the correction, land and deal with what the world says. Too much pink line fever these days.
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The C-17 that landed at Peter O'Knight in Florida was flying a visual approach in VFR conditions.

dans2992 said:
I bet the big iron pilots who landed at the wrong airports wish they had a little more of that fever.
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The 747 that landed at Jabara was on a GPS approach.
 
Using the airport location and OBS mode on the GPS will not necessarily align with the runway. The airport location is at the geographically weighted center of all the runways. If there is a single runway, then the airport location in the GPS database will be in the center of the runway. However, when you have multiple runways, it will more likely be offset to one side or the other, for example for two parallel runways of identical length and laterally aligned, it will be centered half way between the two runways and flying that path can put you too close to the adjacent runway.

I prefer to load an RNAV approach and instead of activating it or using VTF, I move the cursor to the runway threshold and activate the leg that ends at the threshold. This is similar to VTF with one improvement for WAAS approaches with vertical guidance, it allows both the lateral guidance and GS to be available, even though you are joining the approach on a base leg well inside the FAF. This is often the case when being provided with a visual approach where you may have the airport in sight, but not necessarily the landing runway. It is especially helpful at night when there isn't a PAPI available or before you have the runway in sight.
 
Capt. Geoffrey Thorpe said:
If there is an error in your GPS position due to some kind of testing, how does Foreflight actually point to a runway where it actually is, and how would your GPS approach take you to the right place since they all rely on GPS?
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Doggone good point. Maybe next time I go I will get a screenshot. But interestingly I was using my new i6+ and not my iPad, and it wasnt sequencing waypoints. Undoubtetly user error (?).
 
VFR flying in for the visual, I'll often dial up and activate a LPV or so,etching, direct to the FAF, ill fly it visually but having those indicators is nice.
 
Jaybird180 said:
Recently, I was cleared by Class-D for a Straight-in to my destination. I've noticed what I consider a large amount of off-set when arriving to this particular airport. I believe there may be GPS testing nearby without NOTAMS often, as it can be off my several miles one day or reasonably accurate the next. This particular flight, the magenta line again will not take us to the airport. The airport happens to have crossing runways, so I expect the GPS to be plotted for the center of the airfield. But because of the aforementioned inaccuracy it will not.
Click to expand...

Why do you believe there is unpublished GPS testing? If you have an approach certified GPS, the integrity monitoring will alert if GPS is not functioning properly--it's not going to give you a bogus location like you might see on your smart phone. I fly in the Hampton Roads area frequently and never had a problem with GPS.

As others mentioned, the airport reference point at PHF is in the field between the two runways, not at the intersection. That and a 3 degree difference may account for why things don't appear well aligned.
 
John Collins said:
I prefer to load an RNAV approach and instead of activating it or using VTF, I move the cursor to the runway threshold and activate the leg that ends at the threshold. This is similar to VTF with one improvement for WAAS approaches with vertical guidance, it allows both the lateral guidance and GS to be available,
Click to expand...


Great tip.....Thanks
 
Brad Z said:
Why do you believe there is unpublished GPS testing? If you have an approach certified GPS, the integrity monitoring will alert if GPS is not functioning properly--it's not going to give you a bogus location like you might see on your smart phone. I fly in the Hampton Roads area frequently and never had a problem with GPS.

As others mentioned, the airport reference point at PHF is in the field between the two runways, not at the intersection. That and a 3 degree difference may account for why things don't appear well aligned.
Click to expand...

I can tell you this: this is not the first time, I was close enough to spot the airport and that if I continued on the course ahead, I would not arrive. Is it possible that I entered the wrong Identifier? Sure. But unlikely.

First time was at night about 3 years ago I had to tower flash the runway lights to find it.

(Tin Foil hat time: You do know that Langley is nearby, right?)
 
I was close enough to spot the airport and that if I continued on the course ahead, I would not arrive.
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We don't have a panel mount GPS, but a handheld. It will, if you set a course a pretty good distance away and during the flight get blown off course, try to return you to the original course even though you are a couple miles from the airport. A little disconcerting to see the GPS telling you to fly right when the airport is straight ahead. It is easily corrected by using "direct to" to reset the course. Could it be something like this?
 
If I'm coming into an airport with more than one runway and been cleared for a visual approach I will load up an approach for that runway just to make sure I am aiming for the right one. Sometimes you can have two runways that are only 30-45 degrees off from each other and having an extra indication to confirm you're on the right approach can only help. If iits just a single runway then I usually don't bother unless it is at night.
 
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