In several airports in Australia serving international (wide body) aircraft there is a chart note depicting PAPI MEHT or Mean Eye Height at Threshold. Typically 72 feet. This is because the PAPI installation is further down the runway than a normal PAPI to cater for a long aircraft (wide body) Thus on an ILS 3 degree indication on slope for a Boeing 737 for example, a PAPI will show 3 reds and one while.