Interference on communication frequency causes flight crew controller confusion.

Attributes
ACN	249697
Time
Date	199308
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : air
State Reference	OH
Altitude	msl bound lower : 4000 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : pit
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : cfi pilot : atp pilot : instrument
Experience	flight time last 90 days : 160 flight time total : 9400 flight time type : 1300
ASRS Report	249697
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : unable
Consequence	Other
Supplementary
Primary Problem	Navigational Facility
Air Traffic Incident	other
Situations
ATC Facility	other physical facility
Navigational Aid	Unspecified

Narrative:

Descending into pit, we experienced and reported 'bleedover' on both approach control frequencys we used (this happened to many other aircraft). It also apparently confused the controller on one position -- she definitely issued a turn and descent to us, then later rescinded it (she gave it clearly and it was read back clearly), and actually at one point said it was meant for another aircraft (there was so much bleedover she may not have given the clearance at all -- maybe somebody else did). No conflict, but this communication problem needs to be corrected soon (as I said, it has also been reported to other sources). Callback conversation with reporter revealed the following information: spoke to a pit TRACON controller. He said that the problem is the common frequency 121.25 used by TRACON and fwa ATIS. He described the problem as intermittent. The solution was to ask those at fwa to reduce the power of the ATIS transmitter. He said that, occasionally, some technician will forget and tweak the transmitter to produce more power. He said the problem seldom occurred and he considered it minor.

Original NASA ASRS Text

Title: INTERFERENCE ON COM FREQ CAUSES FLC CTLR CONFUSION.

Narrative: DSNDING INTO PIT, WE EXPERIENCED AND RPTED 'BLEEDOVER' ON BOTH APCH CTL FREQS WE USED (THIS HAPPENED TO MANY OTHER ACFT). IT ALSO APPARENTLY CONFUSED THE CTLR ON ONE POS -- SHE DEFINITELY ISSUED A TURN AND DSCNT TO US, THEN LATER RESCINDED IT (SHE GAVE IT CLRLY AND IT WAS READ BACK CLRLY), AND ACTUALLY AT ONE POINT SAID IT WAS MEANT FOR ANOTHER ACFT (THERE WAS SO MUCH BLEEDOVER SHE MAY NOT HAVE GIVEN THE CLRNC AT ALL -- MAYBE SOMEBODY ELSE DID). NO CONFLICT, BUT THIS COM PROB NEEDS TO BE CORRECTED SOON (AS I SAID, IT HAS ALSO BEEN RPTED TO OTHER SOURCES). CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: SPOKE TO A PIT TRACON CTLR. HE SAID THAT THE PROB IS THE COMMON FREQ 121.25 USED BY TRACON AND FWA ATIS. HE DESCRIBED THE PROB AS INTERMITTENT. THE SOLUTION WAS TO ASK THOSE AT FWA TO REDUCE THE PWR OF THE ATIS XMITTER. HE SAID THAT, OCCASIONALLY, SOME TECHNICIAN WILL FORGET AND TWEAK THE XMITTER TO PRODUCE MORE PWR. HE SAID THE PROB SELDOM OCCURRED AND HE CONSIDERED IT MINOR.

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.