Visual Glideslope Indicators

skyflyer8

skyflyer8

Line Up and Wait
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skyflyr
Working on a ground school lesson plan got me wondering.

I see standard VASI and PAPI light systems all the time.

I can only think of one airport where I've seen a pulsating VASI (Portage WI). I have never seen a tri-color VASI or an "alignment of elements" system. IOW it appears these three are very rare.

Just how common are the pulsating VASI, tri-color VASI, and alignment of elements systems? Are there certain areas of the country where they are more common?
 
During instrument training, I recall being told the tri-color's were pretty rare.

I see Cooperstown, NY (K23) has one. Maple Grove Heliport (E66) in Fowlerville, MI is supposed to have one.

Airnav.com will indicate if one is used. I wish there a way to search the site.
 
I've only seen a couple of "alignment of elements" indicators...one that I remember vividly (mostly due to the trees in the landing lights because we misinterpreted it) was in Warrenton, VA...there's two airports there, IIRC, and I've heard that they no longer have the alignment indicators there.

Never seen either of the other two.

Fly safe!

David
 
The old Summerville, SC airport had "alignment of elements" illuminated by floodlights.

I've seen a few others around the southeast, mostly at very small airports.
 
The PVASI is not very common -- the only place I've seen one is at Martin State Airport in Baltimore MD. I believe I've seen a tri-color VASI a couple of times, but not often. OTOH, I've seen lots of AOE units, particularly at smaller airports -- they're pretty cheap to install. As an aside, I believe that the AOE system is far and away the best, because it's the only one that gives you a truly precise idea not only of your current vertical position, but also your trend. It's the closest thing to the Fresnel Lens Optical Landing System (aka "the meatball") used by the Navy for landing on aircraft carriers.

For those unfamiliar with some of these gizmos, see AIM Section 2-1-2 for descriptions and pictures of everything but the FLOLS. For more on "the meatball," see http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=ADA038456&Location=U2&doc=GetTRDoc.pdf or do a low approach at a Naval Air Station (just don't touch down).
 
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Ron, where did the term "meatball" come from? The red lights of the wave-off indicator? I recall the light array by the LSO but I don't recall it being that large. The document mentions it being placed "two-thirds" down the ramp which seems far behind where I recall the LSO standing.

I see they actually use the "technical term" in the document. It's also been a while since I've thought about the romanticism of Navy abbreviations. :)
 
KennyFlys said:
Ron, where did the term "meatball" come from?
Click to expand...
The big yellow ball in the middle. Yeah, I know, it's not the color of a meatball (with or without sauce), but that's what it's called.
I recall the light array by the LSO but I don't recall it being that large.
Click to expand...
Yeah, it's a big sumbitch.
The document mentions it being placed "two-thirds" down the ramp which seems far behind where I recall the LSO standing.
Click to expand...
It is -- the LSO's are well in front of the ball.
 
About this big

web_970303-N-4989W-001.jpg


Ron Levy said:
The big yellow ball in the middle. Yeah, I know, it's not the color of a meatball (with or without sauce), but that's what it's called.
Yeah, it's a big sumbitch.
It is -- the LSO's are well in front of the ball.
Click to expand...
 
Richmond RI 08R has a tri color VASI according to the AFD but it was not lit up the only time I landed there...

-Skip
 
Thanks for the responses so far especially the mention of specific airports. Ron I never even thought about the trend function of the AOE system. Good point.
 
I've seen a few pulsating VASIs in my time....Belen used to have one, and I think at least one other NM airport does too...

kinda neat.
 
Good question, Kate. You can use the "site:" modifier on Google's search to narrow all search results to those that come from a specific site. Using that feature to search Airnav's airport data, I get this:

PVASI systems - 38 or so
Tri-color VASI systems - 55 or so
Alignment of Indicators systems - 10 or so (look at the search string/url for this one, pretty cool... you use the minus indicator in the search to specifically EXCLUDE the VASI and PAPI visual slope indicators, and what you end up with left over is all the other stuff)

I also learned from this search that there are 2-, 4-, and 6-box VASIs.

To find instances of these systems near you, just add your state name to the Google query box after the results show up, and re-run the query. Looks like a trip to Lampasas, TX (KLZZ) may be in the plans for me... so I can see a Pulsating VASI in operation. And a short hop over to San Saba will let me experience a tri-color VASI, too. Time to go re-read relevant portions of the AIM.
 
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TangoWhiskey said:
(snip) You can use the "site:" modifier on Google's search to narrow all search results to those that come from a specific site. (snip)
Click to expand...

Troy that is an excellent tip!!! I wouldn't have thought of using a special search function on Google. (I am liking Google more & more... made the Gmail switch recently, love iGoogle, etc.) Back on topic, I will try out your idea.

I'm guessing you searched in just your own state?
 
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