Narrative:

The first problem we had was radar failure about 180 mi out. I was not concerned since WX was all shown to be to west of destination with good forecast till after arrival time. Then about 150 mi out, ulf became unreliable. Then, about 100 mi out, we realized we had lost all communications. I figured we had a serious avionics problem and wondered what would fail next. We had already been cleared down to FL310, and dir to cos. Now I see a large area of WX directly ahead. Of course with no radar, I couldn't ascertain how widespread this could be. I recall an incident a couple of yrs ago where a wwii tried to negotiate WX west/O radar and ended up crashing. I knew I couldn't penetrate this WX. I knew that will loss of communication, I was supposed to continue to destination, descend and land. But there was no way I could do this west/O going into the WX. Well, I was still in the clear and could see the ground. I felt confident there was no traffic below, since they would all be deviating around this area. I didn't want to climb because there could have been someone there. The same seemed true of going around. The only recourse was to descend in the clear and get below controled airspace as quickly as possible. So I began a 360 degree turn along with a fairly rapid descent. At about 17000' we managed to restore communication and were cleared on down to 15000' direct to destination. After we were on the ground, I called ZDV to further explain our situation. They said there was no problem since no other traffic was in the area as I had surmised. In retrospect, I didn't like what I had to do, but at the same time I didn't know what else I could have done under the circumstances. We couldn't determine what caused our communication problem. The radar was repaired the following day. This also illustrates how fickle WX forecasts can be.

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Original NASA ASRS Text

Title: LTT IFR, BUT IN VMC LOST CONTACT WITH ATC.

Narrative: THE FIRST PROB WE HAD WAS RADAR FAILURE ABOUT 180 MI OUT. I WAS NOT CONCERNED SINCE WX WAS ALL SHOWN TO BE TO W OF DEST WITH GOOD FORECAST TILL AFTER ARR TIME. THEN ABOUT 150 MI OUT, ULF BECAME UNRELIABLE. THEN, ABOUT 100 MI OUT, WE REALIZED WE HAD LOST ALL COMS. I FIGURED WE HAD A SERIOUS AVIONICS PROB AND WONDERED WHAT WOULD FAIL NEXT. WE HAD ALREADY BEEN CLRED DOWN TO FL310, AND DIR TO COS. NOW I SEE A LARGE AREA OF WX DIRECTLY AHEAD. OF COURSE WITH NO RADAR, I COULDN'T ASCERTAIN HOW WIDESPREAD THIS COULD BE. I RECALL AN INCIDENT A COUPLE OF YRS AGO WHERE A WWII TRIED TO NEGOTIATE WX W/O RADAR AND ENDED UP CRASHING. I KNEW I COULDN'T PENETRATE THIS WX. I KNEW THAT WILL LOSS OF COM, I WAS SUPPOSED TO CONTINUE TO DEST, DSND AND LAND. BUT THERE WAS NO WAY I COULD DO THIS W/O GOING INTO THE WX. WELL, I WAS STILL IN THE CLR AND COULD SEE THE GND. I FELT CONFIDENT THERE WAS NO TFC BELOW, SINCE THEY WOULD ALL BE DEVIATING AROUND THIS AREA. I DIDN'T WANT TO CLB BECAUSE THERE COULD HAVE BEEN SOMEONE THERE. THE SAME SEEMED TRUE OF GOING AROUND. THE ONLY RECOURSE WAS TO DSND IN THE CLR AND GET BELOW CTLED AIRSPACE AS QUICKLY AS POSSIBLE. SO I BEGAN A 360 DEG TURN ALONG WITH A FAIRLY RAPID DSNT. AT ABOUT 17000' WE MANAGED TO RESTORE COM AND WERE CLRED ON DOWN TO 15000' DIRECT TO DEST. AFTER WE WERE ON THE GND, I CALLED ZDV TO FURTHER EXPLAIN OUR SITUATION. THEY SAID THERE WAS NO PROB SINCE NO OTHER TFC WAS IN THE AREA AS I HAD SURMISED. IN RETROSPECT, I DIDN'T LIKE WHAT I HAD TO DO, BUT AT THE SAME TIME I DIDN'T KNOW WHAT ELSE I COULD HAVE DONE UNDER THE CIRCUMSTANCES. WE COULDN'T DETERMINE WHAT CAUSED OUR COM PROB. THE RADAR WAS REPAIRED THE FOLLOWING DAY. THIS ALSO ILLUSTRATES HOW FICKLE WX FORECASTS CAN BE.

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.