PAPI lights in the classic era

[Deleted]

A forum search suggests that this topic has not been raised before, but if it has please delete this thread. I have twice recently flown into Antwerp (EBAW), which is part of the excellent Central Europe 1961 scenery, and was surprised to find that the runways have no PAPI lights. It makes little difference on runway 29, which has ILS,  but quite a lot on Runway 11, which does not. My first reaction was that this must be some kind of error in the scenery, but having done a little research (Wikipedia) I now find that PAPI lights were not developed until the 1970s, whereas ILS is much older. Should the former therefore be absent from all the classic airports, or was there (although I guess not) an earlier equivalent?  I look forward to the erudite replies so characteristic of this forum.
Ken

[Tom/CalClassic]

Hi, AFAIK VASI lights were just being introduced in the early 1960's. I think a few big airports had them by 1962. PAPI lights came later. We have been using VASI 21 lights (2 single lights down the runway) in our sceneries because it is so much harder to judge a glide slope in FS than it is in real life. But for maximum accuracy they probably shouldn't be there, for the most part.

[Defender]

Hi,

Here's extracts from the FAA's "Historical Chronology" paper,

Oct 12, 1970: FAA announced adoption of a three-bar version of the visual approach slope indicator (VASI) system. VASI had been adopted as the U.S. national standard in 1961 and became the international standard shortly thereafter. The bicolor (red-white) light box system was located alongside the runway at its touchdown or aiming point. When the pilot was on the proper glide slope, the far indicator was red and the closer one was white. When the pilot was above the glide slope, both indicators were white; when below the glide path, both were red. The specialized three-bar VASI was primarily for runways which were not equipped with the Instrument Landing System and which served new, large jets, such as the Boeing 747, whose pilots sat high above the landing gear. Pilots flying these jets would use the second and third bars for reference, while pilots of smaller aircraft would use the first and second bars. (See Feb 8, 1985.)Feb 8, 1985: FAA established a policy that the Precision Approach Path Indicator (PAPI) would be the standard visual glideslope indicator for new, Federally-funded installations at fixed-wing airports. PAPI was an improved version of VASI, the Visual Approach Slope Indicator (see Oct 12, 1970). The PAPI system featured four bars of light and was able to give pilots an indication of the extent of their deviation from the desired glide path, rather than merely warning that they were too high or too low. In 1982, the International Civil Aviation Organization had adopted PAPI to replace VASI, which would cease to be the international standard on Jan 1, 1995. In May 1983, FAA had changed its longstanding policy of funding only VASI to one permitting funding of various different systems, with the exception that only PAPI was funded for international airports. The agency's Feb 1985 shift to exclusive funding of PAPI reflected a desire to promote safety through standardization. In response to congressional action, however, FAA modified this policy to permit funding of systems other than PAPI at general aviation airports not certificated for air carrier use.



Feb 8, 1985: FAA established a policy that the Precision Approach Path Indicator (PAPI) would be the standard visual glideslope indicator for new, Federally-funded installations at fixed-wing airports. PAPI was an improved version of VASI, the Visual Approach Slope Indicator (see Oct 12, 1970). The PAPI system featured four bars of light and was able to give pilots an indication of the extent of their deviation from the desired glide path, rather than merely warning that they were too high or too low. In 1982, the International Civil Aviation Organization had adopted PAPI to replace VASI, which would cease to be the international standard on Jan 1, 1995. In May 1983, FAA had changed its longstanding policy of funding only VASI to one permitting funding of various different systems, with the exception that only PAPI was funded for international airports. The agency's Feb 1985 shift to exclusive funding of PAPI reflected a desire to promote safety through standardization. In response to congressional action, however, FAA modified this policy to permit funding of systems other than PAPI at general aviation airports not certificated for air carrier use.

However odd it seems by modern standards, this VASI/ILS either/or seems to have continued to be standard practice in the USA at least through the 60's, even at the major airports according to charts. Strange economy considering the frequency of ILS "outages". The UK and possibly Europe seem to have had no such limitation and from about 1961/62 both ILS and VASI started to become available on the same runway.

Interestingly, I've a few mid-50's charts from the UK which show what they called "angle of approach" lighting, whatever that was. But not universal, Birmingham had it, London Airport (now Heathrow) did not.

Bill 

[richjb]

Bill,

Do you have a link to the FAA History paper???

Thanks!

Rich Boll
Wichita, KS

[Pixel Pilot]

Rich,

Here is the link that I think that you want. FAA Historical Chronology

Ed