The
siting of PAPI
wing bars is arrived at by calculation. Airport Lighting Specialists
are able to calculate the correct distance from the runway threshold
to the PAPI wing bar . A simple method to establish the approximate
distance is by use of the PAPI estimator that can be downloaded from
this page.
The
performance and calibration of Research Engineers PAPI projectors, clinometer
and veracity of the relationship between the two can be verified
on the ground, cheaply, quickly and independently by a licenced surveyor.
The
method used is to observe the PAPI transition, note the mid point, construct
a parallel with it, and to measure this directly with a theodolite.