Narrative:

Total of 5 aircraft overflying eri airspace to the cleveland area at altitudes of 4000 ft and 6000 ft. When aircraft neared common boundary of cle and eri approach control, eri could no longer communicate with these aircraft on frequency 121.0 MHZ. Fortunately cle approach had taken radar handoffs on these aircraft, as they proceeded into their airspace. 121.0 MHZ is the main frequency for eri approach control. It was subsequently discovered (from airways facilities evaluators) that since the FAA reduced power on transmitters to 10 watts, the maximum usable distance of the 2 eri transmitters is 121.0 MHZ = 35 NM, 124.65 MHZ = 30 NM. Eri airspace extends to 47 NM to the west and 65 NM to the east. So we routinely attempt to communicate with aircraft over twice the maximum usable distance of our equipment.

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Original NASA ASRS Text

Title: ERI XMITTER OUTPUT WAS REDUCED TO 10 WATTS CAUSING APCH CTL TO HAVE COM PROBS WITH ACFT.

Narrative: TOTAL OF 5 ACFT OVERFLYING ERI AIRSPACE TO THE CLEVELAND AREA AT ALTS OF 4000 FT AND 6000 FT. WHEN ACFT NEARED COMMON BOUNDARY OF CLE AND ERI APCH CTL, ERI COULD NO LONGER COMMUNICATE WITH THESE ACFT ON FREQ 121.0 MHZ. FORTUNATELY CLE APCH HAD TAKEN RADAR HDOFS ON THESE ACFT, AS THEY PROCEEDED INTO THEIR AIRSPACE. 121.0 MHZ IS THE MAIN FREQ FOR ERI APCH CTL. IT WAS SUBSEQUENTLY DISCOVERED (FROM AIRWAYS FACILITIES EVALUATORS) THAT SINCE THE FAA REDUCED PWR ON XMITTERS TO 10 WATTS, THE MAX USABLE DISTANCE OF THE 2 ERI XMITTERS IS 121.0 MHZ = 35 NM, 124.65 MHZ = 30 NM. ERI AIRSPACE EXTENDS TO 47 NM TO THE W AND 65 NM TO THE E. SO WE ROUTINELY ATTEMPT TO COMMUNICATE WITH ACFT OVER TWICE THE MAX USABLE DISTANCE OF OUR EQUIP.

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.