TCASII COMMENTS ABOUT PROPOSED AURAL TCASII CHANGES.

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PER OUR TELECON THIS AM I AM ENCLOSING THE TABLE TBD1 THAT PROPOSES ALTERING THE TCASII WARNINGS (VISUALS AND AURAL). THERE IS A RELUCTANCE BY SOME PLTS TO EXPEDITIOUSLY RETURN TO THEIR CLRNC ALT AFTER REACTING TO A TCASII RA THAT DIRECTS THE PLT TO DEVIATE FROM HIS/HER 'CLRED' ALT. THIS RELUCTANCE TO RETURN TO ALT ALSO IS EXPRESSED IN A SIMILAR MANNER WHEN RESPONDING TO A TCASII 'CLB' OR 'DSND' COMMAND; IE; IF 1500 FPM IS GOOD 3500 FPM MUST BE BETTER. IN AN ATTEMPT TO ACHIEVE A MORE ACCURATE PLT RESPONSE TO TCASII COMMANDS; I AM VERY HAPPY TO SEE THE PROPOSED ADDITION OF A GREEN 'FLY TO' ARC THAT IS PROPOSED; BUT EXTREMELY CONCERNED THAT THE PROPOSED ADDITION OF THE WORDS 'MAINTAIN' AND 'ADJUST' ARE SUBJECT TO MISINTERP AND AMBIGUITY BY PLTS. I HAVE BEEN INVOLVED IN THE TCASII PROGRAM SINCE 1989. I HAVE SERVED AS THE TCASII PROGRAM MGR FOR X AIRLINES SINCE WE STARTED TCASII INSTALLATION; AND HAVE READ EVERY PLT RPT (OVER 600) SUBMITTED BY OUR PLTS AND HAVE HEARD ANECDOTAL EVIDENCE OF A GREAT MANY TCASII ENCOUNTERS. ONE INCIDENT STICKS IN MY MEMORY; THAT OF A PLT RELATING TO ME HIS TCASII AURAL WARNING TO 'DIVE; DIVE'! UPON BEING ADVISED THAT THE SOFTWARE CANNOT PRODUCE THAT PARTICULAR AURAL WARNING; HE INFORMED ME TO 'CHK WITH BENDIX AND SEE WHO PUT IT IN THEIR MACHINE; BECAUSE THAT'S WHAT IT SAID; 'DIVE; DIVE'! THAT IS HIS PERCEPTION OF WHAT THE AURAL COMMAND HE HEARD WAS (IN ALL REALITY; IT WAS CLOSE ENOUGH); AND NO AMOUNT OF FACTS OR DATA WOULD PERSUADE HIM HE 'HEARD' DIFFERENTLY. 'PERCEPTION IS REALITY.' I HAVE FLOWN TCASII; I'VE BEEN AMONG LARGE INTL GROUPS THAT HAVE DEBATED TCASII; I'VE DEFENDED TCASII; AND I BELIEVE IN TCASII; BUT THIS CHANGE CAUSES THE PLT TO HEAR A 'TWO WORD SET' MESSAGE. EITHER 'ADJUST;' 'MAINTAIN;' OR 'MONITOR;' VERT SPD; EVEN THROUGH THE WORD 'MAINTAIN' OR 'ADJUST' IS REPEATED AFTER VERT SPD. THE COMMAND; IN MY MIND; WILL DO NOTHING TO IMPROVE THE ACCURACY OF PLT COMPLIANCE TO THE COMMAND; AND WILL OR COULD INTRODUCE A HERETOFORE UNKNOWN REACTION TO THE TCASII SYS. THE PLT WILL NOT; IN ALL LIKELIHOOD; HEAR ADJUST; MONITOR; OR MAINTAIN; HE WILL ONLY HEAR 'VERT SPD.' ENCLOSED IS A LETTER THAT RELATES TO THE SUBJECT. I HAVE ATTEMPTED TO CONTACT HIM BUT WE'VE PLAYED TELEPHONE TAG SO FAR. PLEASE ASSIST ME IN THIS MATTER AS YOU ARE ABLE. I AM NOT ADVERSE TO SHARING THIS INFO WITH ANY PARTY THAT MIGHT BE INTERESTED IN THE IMPROVEMENT OF SAFETY; BE IT IN THE HUMAN FACTORS AREA OR TCASII.