Pilot of a BE55 experienced a loss of communication while departing pwk on an IFR flight plan. The m...

Narrative:

I departed palwaukee airport on an IFR flight plan. When the palwaukee tower controller handed me off to chicago departure, I found I could not talk to the new controller. Brief experimentation revealed that I could hear incoming transmission, and that I could send out carrier wave xmissions, but I could not make my voice heard. My 1976 beechcraft baron B55 has the microphone jack receptacle mounted vertically inside a pedestal between the front seats. Examination showed that the microphone jack receptacle retaining nut had worked itself off the receptacle, allowing the receptacle to fall down into the pedestal interior and disconnecting the microphone jack. I could not manually retrieve the jack receptacle while flying the airplane. The chicago departure controller found that she could communicate with me by having me squawk identify on my transponder to acknowledge her instructions. She then discovered that she could more quickly obtain my acknowledgment of her xmissions by having me depress my push-to-talk microphone switch twice in rapid succession. Using this method, she turned me around to return and intercept the palwaukee ILS. She handed me off to the tower, and I landed and taxied back to my hangar uneventfully. I have had my aircraft repaired and I suggest all barons, and all other aircraft having these jack plug receptacles, which are vertically mounted inside a pedestal, be checked to be sure that the receptacles are securely mounted below the pedestal tops, and that the retaining nuts are tightened. These retaining nuts should be replaced with lock nuts or lock washers and nuts to insure that the microphone plug jacks do not work loose and separate from the microphone plugs in-flight. The adjacent headphone jack plug receptacles should also be checked. Callback conversation with reporter revealed the following information: this reporter has since reviewed pilot's technical manual and has found no new solution for this situation other than preventive maintenance. Reporter will pass along his experience to the local dealer FBO -- so other barons might be checked.

Original NASA ASRS Text

Title: PLT OF A BE55 EXPERIENCED A LOSS OF COM WHILE DEPARTING PWK ON AN IFR FLT PLAN. THE MIKE JACK RECEPTACLE FELL OFF THE PEDESTAL INTERIOR, DISCONNECTING THE MIKE JACK, WHICH PREVENTED VOICE MODULATION. THE RPTR WAS UNABLE TO RETRIEVE THE RECEPTACLE WHILE FLYING, SO HE TURNED BACK TOWARD A NON TWR ARPT AND THEREBY RECEIVED ATC ATTN AND VECTORS THROUGH CARRIER WAVE XMISSION ACKNOWLEDGMENT.

Narrative: I DEPARTED PALWAUKEE ARPT ON AN IFR FLT PLAN. WHEN THE PALWAUKEE TWR CTLR HANDED ME OFF TO CHICAGO DEP, I FOUND I COULD NOT TALK TO THE NEW CTLR. BRIEF EXPERIMENTATION REVEALED THAT I COULD HEAR INCOMING XMISSION, AND THAT I COULD SEND OUT CARRIER WAVE XMISSIONS, BUT I COULD NOT MAKE MY VOICE HEARD. MY 1976 BEECHCRAFT BARON B55 HAS THE MIKE JACK RECEPTACLE MOUNTED VERTLY INSIDE A PEDESTAL BTWN THE FRONT SEATS. EXAMINATION SHOWED THAT THE MIKE JACK RECEPTACLE RETAINING NUT HAD WORKED ITSELF OFF THE RECEPTACLE, ALLOWING THE RECEPTACLE TO FALL DOWN INTO THE PEDESTAL INTERIOR AND DISCONNECTING THE MIKE JACK. I COULD NOT MANUALLY RETRIEVE THE JACK RECEPTACLE WHILE FLYING THE AIRPLANE. THE CHICAGO DEP CTLR FOUND THAT SHE COULD COMMUNICATE WITH ME BY HAVING ME SQUAWK IDENT ON MY XPONDER TO ACKNOWLEDGE HER INSTRUCTIONS. SHE THEN DISCOVERED THAT SHE COULD MORE QUICKLY OBTAIN MY ACKNOWLEDGMENT OF HER XMISSIONS BY HAVING ME DEPRESS MY PUSH-TO-TALK MIKE SWITCH TWICE IN RAPID SUCCESSION. USING THIS METHOD, SHE TURNED ME AROUND TO RETURN AND INTERCEPT THE PALWAUKEE ILS. SHE HANDED ME OFF TO THE TWR, AND I LANDED AND TAXIED BACK TO MY HANGAR UNEVENTFULLY. I HAVE HAD MY ACFT REPAIRED AND I SUGGEST ALL BARONS, AND ALL OTHER ACFT HAVING THESE JACK PLUG RECEPTACLES, WHICH ARE VERTLY MOUNTED INSIDE A PEDESTAL, BE CHKED TO BE SURE THAT THE RECEPTACLES ARE SECURELY MOUNTED BELOW THE PEDESTAL TOPS, AND THAT THE RETAINING NUTS ARE TIGHTENED. THESE RETAINING NUTS SHOULD BE REPLACED WITH LOCK NUTS OR LOCK WASHERS AND NUTS TO INSURE THAT THE MIKE PLUG JACKS DO NOT WORK LOOSE AND SEPARATE FROM THE MIKE PLUGS INFLT. THE ADJACENT HEADPHONE JACK PLUG RECEPTACLES SHOULD ALSO BE CHKED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THIS RPTR HAS SINCE REVIEWED PLT'S TECHNICAL MANUAL AND HAS FOUND NO NEW SOLUTION FOR THIS SIT OTHER THAN PREVENTIVE MAINT. RPTR WILL PASS ALONG HIS EXPERIENCE TO THE LCL DEALER FBO -- SO OTHER BARONS MIGHT BE CHKED.

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.

Attributes
ACN	355353
Time
Date	199612
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : obk airport : pwk
State Reference	IL
Altitude	msl bound lower : 1000 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : ord
Operator	general aviation : personal
Make Model Name	Baron 55/Cochise
Operating Under FAR Part	Part 91
Flight Phase	climbout : initial
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : private
Experience	flight time last 90 days : 30 flight time total : 3000 flight time type : 1000
ASRS Report	355353
Person 2
Affiliation	government : faa
Function	controller : departure
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : less severe
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other