CHK AIRMAN FOR MAJOR ACR BELIEVES PHX ILS RWY 7L; (GS OUT) APCH REQUIRES RATES OF DSCNT IN EXCESS OF THOSE CHARTED IN ORDER TO BE IN POS TO LAND AT MDA.

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PROB WITH ILS RWY 7L GS OTS -- PHX. I AM A CHK AIRMAN AND HAVE PERFORMED AS THE EVALUATOR FOR SEVERAL SIMULATOR CHK RIDES THIS MONTH ON THE MD80. I GAVE A SCENARIO IN WHICH PLTS TYPICALLY DECIDE TO RETURN TO PHX. THE SCENARIO CALLS FOR AN ILS RWY 7L GS OTS. AS I'VE OBSERVED SEVERAL OF THESE THIS MONTH; I BELIEVE IT IS A PROB. YOU REACH THE FAF AT 2600 FT MSL. THE MDA IS ROUNDED UP TO 1500 FT MSL. YOU ONLY HAVE TO LOSE 1100 FT. THE DSCNT CHART FOR 140 KTS OF GND SPD CALLS FOR 753 FPM RATE OF DSCNT. MOST CREWS CHOOSE THIS FIGURE AND ROUND IT TO 800 FPM RATE OF DSCNT. EVERY CREW THAT HAS DONE THIS HAS BEEN STEEP WHEN THEY FINALLY GET TO A POINT WHERE THE RWY IS REALLY IN VIEW WELL ENOUGH TO LAND. IF I FIGURE OUT A VDP FOR THIS APCH FOR THE MDA ALT OF 1500 FT MSL -- THE DME FOR A NORMAL RATE OF DSCNT TO LNDG IS APPROX 3.1 DME. THAT'S 385 FT ABOVE THE GND AND FIGURING A 3 DEG GLIDE PATH FOR THAT IS ABOUT 1.2 NM. ADD 1.2 TO 1.9 -- END OF RWY DME -- I COME UP WITH 3.1. IF I TAKE 3.1 AND SUBTRACT IT FROM THE DME AT REYNO -- THE FAF -- 5.9 MINUS 3.1 -- I COME UP WITH 2.8 DME FROM THE FAF TO THE VDP. THE FAF ALT IS 2600 FT. THE MDA ALT IS 1500 FT. I HAVE 1100 FT TO LOSE IN 2.8 DME. THAT WORKS OUT TO 398 FT PER NM. IF MY GND SPD IS 2.5 MI A MIN -- THAT WOULD MEAN MY VERT SPD WOULD BE APPROX 980 FPM RATE OF DSCNT. IF I LOOK AT THE COMMERCIAL CHART FIGURE; IT IS 753 FPM RATE OF DSCNT. MY CONCERN IS THAT EVERY CREW I'VE WATCHED DO THIS APCH HAS BEEN SIGNIFICANTLY STEEP USING 700 OR 800 FPM RATE OF DSCNT AS RECOMMENDED BY THE APCH CHART. IF SOMEONE HAS TO FLY THIS APCH IN REAL WX; THEY WILL DEFINITELY BE GOING AROUND UNLESS THEY ARE AN EMER OR INCREASE THEIR SINK RATE AT THE END OF THE APCH TO WELL ABOVE NORMAL LEVELS. TO ME; THIS IS A SAFETY ISSUE. WE ARE TRAINING CREWS TO USE THE APCH CHART DSCNT RATE ON NON-PRECISION APCHS. IF THIS DSCNT RATE ISN'T ADEQUATE TO PLACE THE ACFT IN A NORMAL POS FOR LNDG; AND THE CREW DOESN'T REALIZE IT UNTIL THE END OF THE APCH; THEY WILL BE IN AN UNSATISFACTORY POS TO LAND.