Narrative:

The FAA has rendered a decision that can easily lead to an unsafe condition in instrument WX during the approach phase of a flight. Specifically, it has intentionally removed the remote alternate altimeter setting (raas) minima from many terminal procedures. As an example, columbus ohio's bolton airport (tzr) terminal procedures dictate that the pilot shall utilize the altimeter setting as derived from the bolton AWOS (or as a backup, the altimeter setting from the bolton ATC tower). However, should the tower be unstaffed (as it is 12 hours each day), and the AWOS be OTS (as it was for 2 evenings this past wkend due to severe WX), the pilot could be left without the appropriate altimeter setting for executing any of the instrument approach procedures. The changes made by the FAA affect all of the terminal procedures. During such an event, all these procedures are considered as not authority/authorized. (Before the AWOS was certified, it used to be that the pilot would simply utilize the cmh altimeter setting and increase the decision altitude or MDA, as appropriate.) this system wide change can impact operators across the nation adversely. However, I feel that the impact of this change has not been widely publicized, and pilots are likely to obtain a clearance for an instrument approach and descend to an unsafe altitude because they are inadvertently utilizing an inappropriate altimeter setting. I feel this change needs to be publicized more so the instrument pilot understands the ramifications better. I also feel that it would be much safer, and provide our nation a much more robust system of airports, if the FAA would simply change things back to the way they used to be, and publish raas minima for airports like this. Callback conversation with an aviation safety inspector revealed the following information: he knew of no problems regarding the AWOS at ktzr. His specific knowledge regarding 'remote altimeter setting' (raas) minima and the FAA's planned removal of same from terminal procedures, was stated as limited.

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Original NASA ASRS Text

Title: A CONCERNED PLT FEELS THE REMOVAL OF 'REMOTE ALTERNATE ALTIMETER SETTING.' (RAAS) MINIMA FROM CERTAIN ARPTS IS A DISSERVICE TO PLTS WHO USE THE SYS.

Narrative: THE FAA HAS RENDERED A DECISION THAT CAN EASILY LEAD TO AN UNSAFE CONDITION IN INST WX DURING THE APCH PHASE OF A FLT. SPECIFICALLY, IT HAS INTENTIONALLY REMOVED THE REMOTE ALTERNATE ALTIMETER SETTING (RAAS) MINIMA FROM MANY TERMINAL PROCS. AS AN EXAMPLE, COLUMBUS OHIO'S BOLTON ARPT (TZR) TERMINAL PROCS DICTATE THAT THE PLT SHALL UTILIZE THE ALTIMETER SETTING AS DERIVED FROM THE BOLTON AWOS (OR AS A BACKUP, THE ALTIMETER SETTING FROM THE BOLTON ATC TWR). HOWEVER, SHOULD THE TWR BE UNSTAFFED (AS IT IS 12 HRS EACH DAY), AND THE AWOS BE OTS (AS IT WAS FOR 2 EVENINGS THIS PAST WKEND DUE TO SEVERE WX), THE PLT COULD BE LEFT WITHOUT THE APPROPRIATE ALTIMETER SETTING FOR EXECUTING ANY OF THE INST APCH PROCS. THE CHANGES MADE BY THE FAA AFFECT ALL OF THE TERMINAL PROCS. DURING SUCH AN EVENT, ALL THESE PROCS ARE CONSIDERED AS NOT AUTH. (BEFORE THE AWOS WAS CERTIFIED, IT USED TO BE THAT THE PLT WOULD SIMPLY UTILIZE THE CMH ALTIMETER SETTING AND INCREASE THE DECISION ALT OR MDA, AS APPROPRIATE.) THIS SYS WIDE CHANGE CAN IMPACT OPERATORS ACROSS THE NATION ADVERSELY. HOWEVER, I FEEL THAT THE IMPACT OF THIS CHANGE HAS NOT BEEN WIDELY PUBLICIZED, AND PLTS ARE LIKELY TO OBTAIN A CLRNC FOR AN INST APCH AND DSND TO AN UNSAFE ALT BECAUSE THEY ARE INADVERTENTLY UTILIZING AN INAPPROPRIATE ALTIMETER SETTING. I FEEL THIS CHANGE NEEDS TO BE PUBLICIZED MORE SO THE INST PLT UNDERSTANDS THE RAMIFICATIONS BETTER. I ALSO FEEL THAT IT WOULD BE MUCH SAFER, AND PROVIDE OUR NATION A MUCH MORE ROBUST SYS OF ARPTS, IF THE FAA WOULD SIMPLY CHANGE THINGS BACK TO THE WAY THEY USED TO BE, AND PUBLISH RAAS MINIMA FOR ARPTS LIKE THIS. CALLBACK CONVERSATION WITH AN AVIATION SAFETY INSPECTOR REVEALED THE FOLLOWING INFO: HE KNEW OF NO PROBS REGARDING THE AWOS AT KTZR. HIS SPECIFIC KNOWLEDGE REGARDING 'REMOTE ALTIMETER SETTING' (RAAS) MINIMA AND THE FAA'S PLANNED REMOVAL OF SAME FROM TERMINAL PROCS, WAS STATED AS LIMITED.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.