Narrative:

I was filed to land at ZZZ on a flight from ZZZ1. Thunderstorm activity in the vicinity of ZZZ picked up on my stormscope prompted my request to leave center frequency to obtain an updated enroute WX report with ZZZ FSS, I was given permission to leave center frequency and called ZZZ FSS 122.2. This transmission on my GPS/communication #1 set off my ELT which blocked (over powered) ZZZ FSS answer. In the process of turning off my ELT I inadvertently disconnected my autoplt. I was on an assigned altitude of 9000 ft at that time. I was advised by ZZZ FSS to use 122.4, but this also set off my ELT. Turbulence at the time was moderate. I thought I re-engaged my autoplt, but did not verify that altitude. Hold was engaged. In the process of trying to communication with ZZZ I did not notice the airplane climb to 11000 ft. When I did notice I corrected the deviation and reported back to ZZZ center. I subsequently was advised that other SR22's have similar problems with the ELT going off with communication, xmissions in the 122 range. My SR22 is now in the shop to get this problem fixed. Callback conversation with reporter revealed the following information: the reporter stated that any transmission on the VHF comm in the 120 to 123 MHZ range will trigger the emergency locator transmitter. The reporter said the emergency locator transmitter is located under the right seat and has a small red button that must be pushed to turn off the unit. The reporter stated that during the reported flight in attempting to find the red button to turn off the emergency locator transmitter the autoplt was inadvertently disconnected resulting in an altitude deviation. The reporter said the airplane is still out of service to correct the problem which cannot be duplicated on the ground. The reporter stated another SR22 is at the maintenance facility with the same problem and the manufacturers of the comm units and the emergency locator units are mainly pointing fingers at each other shifting blame and responsibility. The reporter said the avionics technician at the maintenance facility believes installing filters in the wiring may solve the problem.

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Original NASA ASRS Text

Title: A CIRRUS SR22 PLT RPTS WHEN XMITTING ON VHF COMM IN THE 120 TO 123 MHZ RANGE THE EMER LOCATOR XMITTER IS ACTIVATED.

Narrative: I WAS FILED TO LAND AT ZZZ ON A FLT FROM ZZZ1. THUNDERSTORM ACTIVITY IN THE VICINITY OF ZZZ PICKED UP ON MY STORMSCOPE PROMPTED MY REQUEST TO LEAVE CENTER FREQ TO OBTAIN AN UPDATED ENROUTE WX RPT WITH ZZZ FSS, I WAS GIVEN PERMISSION TO LEAVE CENTER FREQ AND CALLED ZZZ FSS 122.2. THIS XMISSION ON MY GPS/COM #1 SET OFF MY ELT WHICH BLOCKED (OVER POWERED) ZZZ FSS ANSWER. IN THE PROCESS OF TURNING OFF MY ELT I INADVERTENTLY DISCONNECTED MY AUTOPLT. I WAS ON AN ASSIGNED ALT OF 9000 FT AT THAT TIME. I WAS ADVISED BY ZZZ FSS TO USE 122.4, BUT THIS ALSO SET OFF MY ELT. TURB AT THE TIME WAS MODERATE. I THOUGHT I RE-ENGAGED MY AUTOPLT, BUT DID NOT VERIFY THAT ALT. HOLD WAS ENGAGED. IN THE PROCESS OF TRYING TO COM WITH ZZZ I DID NOT NOTICE THE AIRPLANE CLB TO 11000 FT. WHEN I DID NOTICE I CORRECTED THE DEVIATION AND RPTED BACK TO ZZZ CENTER. I SUBSEQUENTLY WAS ADVISED THAT OTHER SR22'S HAVE SIMILAR PROBS WITH THE ELT GOING OFF WITH COM, XMISSIONS IN THE 122 RANGE. MY SR22 IS NOW IN THE SHOP TO GET THIS PROB FIXED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THAT ANY XMISSION ON THE VHF COMM IN THE 120 TO 123 MHZ RANGE WILL TRIGGER THE EMER LOCATOR TRANSMITTER. THE RPTR SAID THE EMER LOCATOR XMITTER IS LOCATED UNDER THE R SEAT AND HAS A SMALL RED BUTTON THAT MUST BE PUSHED TO TURN OFF THE UNIT. THE RPTR STATED THAT DURING THE RPTED FLT IN ATTEMPTING TO FIND THE RED BUTTON TO TURN OFF THE EMER LOCATOR XMITTER THE AUTOPLT WAS INADVERTENTLY DISCONNECTED RESULTING IN AN ALT DEVIATION. THE RPTR SAID THE AIRPLANE IS STILL OUT OF SVC TO CORRECT THE PROB WHICH CANNOT BE DUPLICATED ON THE GND. THE RPTR STATED ANOTHER SR22 IS AT THE MAINT FAC WITH THE SAME PROB AND THE MANUFACTURERS OF THE COMM UNITS AND THE EMER LOCATOR UNITS ARE MAINLY POINTING FINGERS AT EACH OTHER SHIFTING BLAME AND RESPONSIBILITY. THE RPTR SAID THE AVIONICS TECHNICIAN AT THE MAINT FAC BELIEVES INSTALLING FILTERS IN THE WIRING MAY SOLVE THE PROB.

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.