The Clark and Gordon document above was not the only instance of highlighting short-comings of PAPI.
In April1983, the FAA produced a report "Evaluation of Precision Approach Path Indicator (PAPI)
It stated "It was found that during certain weather conditions, condensation could form on the PAPI lenses and produce transient false pink signals which must be eliminated by some means."
Here is the link to the full document, to enable further reading.
Evaluation of PAPI by FAA 1983
I'm harping on the Fedex crash because it still today is quoted by the zealots (private and official) as
THE example of a serious accident
CAUSED BY A PILOT'S DEFECTIVE COLOUR VISION.
The NTSB report into this crash was fatally flawed because:
- the only medical evidence requested by the Board was from an individual whose zealous promotion and protection of rigorous colour perception standards is widely known.. This person introduced evidence far beyond what was require for the forensic inquiry into the crash.
- The NTSB's conclusions failed to consider the evidence from both the FAA's document (posted above) and the Clark ad Gordon Paper that had been circulated to the FAA.
- The testing of the PAPI post accident was carried out in broad daylight with none of the meteorological conditions that were present at the time of the crash.
The ongoing obsession with PAPI by the zealots is based on this flawed NTSB report. The CAD test development was spurred by this crash!!
Offers to provide them with copies of the Clark and Gordon Paper amd tje FAA evaluation are rejected as unnecessary.
Watch this space