Narrative:

With my husband as safety pilot, I took off from ashland one (sob) to klamath falls ore (lmt). The WX at both places and in between was VMC. About 6 mins out I was under the hood, navigating solely by instruments in simulated IFR with the transponder operating mode C. Approximately 16 mi out from lmt, I contacted tower with ATIS altitude, position and requested intentions to fly the NDB 32 approach VFR. I was cleared to the VOR (115.9) and told to report over the VOR. I did so and was told to report inbound from merrel (347). After my procedure turn inbound, I remained at 7100-7200 MSL so as to cross the NDB at the correct ht, at the same time checking for needle swing of 347. When I saw the needle swing and was about to contact tower, my husband said there was a military c- 130 tanker overhead and descending at 12 O'clock. We then encountered wake turbulence and struggled to prevent a roll- over, at the same time breaking off to the right. We then heard tower informing the C-130 that a cherokee was somewhere in his vicinity. After regaining control, I reported to tower why we broke to the right and requested another NDB approach by going back to 347. Tower informed me that this was not possible because ZSE informed them the C-130 was going to do several practice ILS approachs. I then requested and was granted a wbound turn back to ashland. We did not know the tanker was in the vicinity until he was acknowledged by the tower, this being after my husband saw him. The ILS and NDB approachs for runway 32 inbound to 347 are at the same altitude. In the future to prevent larger aircraft from overtaking smaller aircraft (far 91.113) and causing wake turbulence, all approachs should use the same frequency, including military aircraft. If this is not possible, monitoring the center frequency would be advisable.

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Original NASA ASRS Text

Title: RPTR ENCOUNTERED WAKE TURB WHILE PRACTICING NDB APCH IN VMC.

Narrative: WITH MY HUSBAND AS SAFETY PLT, I TOOK OFF FROM ASHLAND ONE (SOB) TO KLAMATH FALLS ORE (LMT). THE WX AT BOTH PLACES AND IN BTWN WAS VMC. ABOUT 6 MINS OUT I WAS UNDER THE HOOD, NAVIGATING SOLELY BY INSTS IN SIMULATED IFR WITH THE XPONDER OPERATING MODE C. APPROX 16 MI OUT FROM LMT, I CONTACTED TWR WITH ATIS ALT, POS AND REQUESTED INTENTIONS TO FLY THE NDB 32 APCH VFR. I WAS CLRED TO THE VOR (115.9) AND TOLD TO RPT OVER THE VOR. I DID SO AND WAS TOLD TO RPT INBOUND FROM MERREL (347). AFTER MY PROC TURN INBOUND, I REMAINED AT 7100-7200 MSL SO AS TO CROSS THE NDB AT THE CORRECT HT, AT THE SAME TIME CHKING FOR NEEDLE SWING OF 347. WHEN I SAW THE NEEDLE SWING AND WAS ABOUT TO CONTACT TWR, MY HUSBAND SAID THERE WAS A MIL C- 130 TANKER OVERHEAD AND DSNDING AT 12 O'CLOCK. WE THEN ENCOUNTERED WAKE TURB AND STRUGGLED TO PREVENT A ROLL- OVER, AT THE SAME TIME BREAKING OFF TO THE R. WE THEN HEARD TWR INFORMING THE C-130 THAT A CHEROKEE WAS SOMEWHERE IN HIS VICINITY. AFTER REGAINING CTL, I RPTED TO TWR WHY WE BROKE TO THE R AND REQUESTED ANOTHER NDB APCH BY GOING BACK TO 347. TWR INFORMED ME THAT THIS WAS NOT POSSIBLE BECAUSE ZSE INFORMED THEM THE C-130 WAS GOING TO DO SEVERAL PRACTICE ILS APCHS. I THEN REQUESTED AND WAS GRANTED A WBOUND TURN BACK TO ASHLAND. WE DID NOT KNOW THE TANKER WAS IN THE VICINITY UNTIL HE WAS ACKNOWLEDGED BY THE TWR, THIS BEING AFTER MY HUSBAND SAW HIM. THE ILS AND NDB APCHS FOR RWY 32 INBOUND TO 347 ARE AT THE SAME ALT. IN THE FUTURE TO PREVENT LARGER ACFT FROM OVERTAKING SMALLER ACFT (FAR 91.113) AND CAUSING WAKE TURB, ALL APCHS SHOULD USE THE SAME FREQ, INCLUDING MIL ACFT. IF THIS IS NOT POSSIBLE, MONITORING THE CTR FREQ WOULD BE ADVISABLE.

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.