HELI PLT REQUESTS GPS APCH AND IS GIVEN A FIX WHICH IS FOR AN LDA APCH BUT SOUNDS QUITE SIMILAR TO THE GPS FIX. HE FLIES THE GPS AND ATC QUERIES. ATC THEN CLRS HIM FOR THE CORRECT GPS FIX.

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I ASKED FOR GPS IAP TO W99 GPS RWY 31. ZDC CLRED ME TO WADDI. WADDI IS FOR THE LDA IAP; SO I THOUGHT HE SAID WABBY WHICH IS FOR THE GPS. CTR WAS UNDERSTANDING AND DID CLR ME FOR WABBY AND THE GPS RWY 31 AT W99. THERE IS A PROB WITH THE NAMING INITIAL APCH FIXES FOR GPS APCHS. ON TWO CONSECUTIVE FLTS TO W99; PETERSBURG; WVA; I HAD TROUBLE COMMUNICATING WITH ZDC AS TO WHICH APCH I WOULD LIKE TO FLY AND WHAT INITIAL APCH FIX CLRNC I WAS CLRED TO. UNDERSTANDING THAT ZDC WAS NOT USED TO HAVING THE GPS APCH FOR PETERSBURG. THE PROB SEEMS TO COME FROM THE NAMES FOR THE IAF'S BTWN THE GPS APCH AND THE LDA APCH. THE IAF ON THESE IS WABBY AND WADDI; ADD EBAWI FOR THE GPS AGAIN AND YOU CAN SEE WHERE CONFUSION MIGHT ARISE IN A BUSY CTR. I ADMIT I AM NOT THE GREATEST WITH PHONICS SO I MADE AN INFORMAL SURVEY OF HOW TO PRONOUNCE THE NAMES FOR SOME APCHS SUCH AS STAUNTON-WAYNESBORO SHENANDOAH VALLEY'S GPS APCH SUCH AS OLAJO; IVLUF OR CHARLOTTESVILLE'S GPS RWY 21 MUSOJ; WITTO; OR ORMEY. THERE SEEMS TO BE A GENERAL CONSENSUS THAT THIS IS A PROB. WE ARE A SINGLE PLT OP; AND THINGS GET VERY BUSY WITH A LOT OF TALKING SO MY TONGUE GETS A BIT TIED WITH THESE NAMES. I HAVE TO SAY I DO REALLY ENJOY USING THE GPS APCHS AS OPPOSED TO NDB OR VOR APCHS. THERE IS NO WANDERING OF NEEDLES AND YOU ALWAYS HAVE MILEAGE TO WAYPOINTS; AND WE HAVE A EHSI WHICH GIVES US A SITUATIONAL VIEW OF WHAT IS GOING ON WITH THE APCH. WE USE THE GPS TO BACK UP AND GIVE US MILEAGE ON ALL INST APCHS. ALSO I WAS WONDERING IF ANY JAMMING MAY HAVE BEEN RPTED IN THE AREA OF W99 I WAS ON THE GPS RWY 31 APCH COMING UP ON PADOH AT APPROX XX15 ON FEB/AB/98; WHEN MY GPS NAV DATA WENT BLANK. I MEAN NOTHING ON THE GPS EXCEPT A MESSAGE; AND WHO HAS TIME TO READ THAT WHILE YOU ARE BY YOURSELF IN THE CLOUDS LETTING DOWN IN MOUNTAINS; AND THE EHSI WAS BLANK OF GPS NAV DATA. IT WAS GONE FOR QUITE A WHILE BEFORE IT CAME BACK WORKING FINE. IF YOU LOOK AT THE APCH YOU WILL SEE THAT THERE IS NO OTHER MEANS FOR NAV TO THE MISSED APCH POINT. RAIM SHOWED AVAILABLE FOR THE APCH. I HAD KESSEL VOR TUNED AND LINDEN VOR IN BACK UP; BUT YOU WILL ALSO NOTE THAT THE VOR FREQS ARE NOT PUBLISHED IN COMMERCIAL PLATES. THANKS FOR LETTING ME RAMBLE ON ABOUT GPS'S; THEY ARE GREAT AND WILL ONLY GET BETTER IN TIME BUT THERE IS A LOT OF EDUCATION INVOLVED WITH IT.