Narrative:

We were trying to beat a cold front and it was not moving as forecast. I knew we had only a certain amount of time on the ground before the second band of WX would hit. So, I moved things along as fast as I could. I was surprised by the rain when we were finally ready to depart and noted the winds had shifted 180 degrees, frontal passage. I rechked all available WX, FSS, and radar briefings. Radar showed green to about 30 mi south, then clear all the way to my destination. I filed IFR, got cleared, encountered light turbulence on the climb, entered the bases on the vector to the airway, and all heck broke loose. On the first jolt of turbulence, I tightened my already tight seatbelt. Thanks to both ASRS and mountain flying clinics for that knowledge. On the second jolt, I tightened the shoulder harness as tight as it would go. I advised my pilot-rated passenger to do the same. He did not. After that, the turbulence was so fast and hard that I advised ATC I was unable to maintain altitude. I was watching the altimeter jump hundreds of ft in both directions. ATC cleared me for a block altitude of a thousand ft. The jolts had emptied my passenger's pockets so there was a cell phone and pens and paperwork flying through the cockpit. Then my passenger hit the ceiling with his head/headset, hard. The passenger's door also popped open. My headset hit the side window, again, and again. We took another hit and dropped 1000 ft. The radio was constant chatter but ATC had just called us, I responded 'mayday mayday mayday, cessna needs an immediate vector to ZZZ.' I know my stress level was extremely high as I do not remember the entire exchange of communications. I do know that I was using ATC fully and the controller was very helpful. In addition, the other pilots on frequency kept their silence, which really helped. The controller issued a few low altitude alerts, but we had dropped out of the bottom of the clouds into about 1/4 mi visibility, and I was able to spot familiar landmarks and knew I could ignore most of the altitude alerts. The turbulence lessened, and the visibility improved. I landed and closed the IFR flight plan. My passenger was shaken but okay. Back on the WX computer I saw the little docile green splotch had turned into a red splotch surrounded by yellows. We waited out the band of WX, then we headed out VFR with 10+ mi visibility. The floor of ZZZ1 class C airspace is 2500 ft MSL. I chose to remain at 2200 ft so as to not crowd the floor of ZZZ1 class C, then climb to 2500 ft and remain below the clouds and above all obstacles. Less than 10 mins after departure, I noticed we were at 2500 ft headed to 2600 ft. I was 2700 ft before I got the climb stopped and the descent started and stopped at 2500 ft. Then I realized I was not out from under ZZZ1 'C' and I still had 3 mi to go. I continued the descent to 2200 ft and stayed there until I was clear of the airspace. ATC gave us direct and we were able to complete the flight without further incident.

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Original NASA ASRS Text

Title: C172 PLT DECLARES EMER AFTER TURB ENCOUNTER AND VIOLATES ZZZ1 CLASS C AIRSPACE ON SUBSEQUENT FLT.

Narrative: WE WERE TRYING TO BEAT A COLD FRONT AND IT WAS NOT MOVING AS FORECAST. I KNEW WE HAD ONLY A CERTAIN AMOUNT OF TIME ON THE GND BEFORE THE SECOND BAND OF WX WOULD HIT. SO, I MOVED THINGS ALONG AS FAST AS I COULD. I WAS SURPRISED BY THE RAIN WHEN WE WERE FINALLY READY TO DEPART AND NOTED THE WINDS HAD SHIFTED 180 DEGS, FRONTAL PASSAGE. I RECHKED ALL AVAILABLE WX, FSS, AND RADAR BRIEFINGS. RADAR SHOWED GREEN TO ABOUT 30 MI S, THEN CLR ALL THE WAY TO MY DEST. I FILED IFR, GOT CLRED, ENCOUNTERED LIGHT TURB ON THE CLB, ENTERED THE BASES ON THE VECTOR TO THE AIRWAY, AND ALL HECK BROKE LOOSE. ON THE FIRST JOLT OF TURB, I TIGHTENED MY ALREADY TIGHT SEATBELT. THANKS TO BOTH ASRS AND MOUNTAIN FLYING CLINICS FOR THAT KNOWLEDGE. ON THE SECOND JOLT, I TIGHTENED THE SHOULDER HARNESS AS TIGHT AS IT WOULD GO. I ADVISED MY PLT-RATED PAX TO DO THE SAME. HE DID NOT. AFTER THAT, THE TURB WAS SO FAST AND HARD THAT I ADVISED ATC I WAS UNABLE TO MAINTAIN ALT. I WAS WATCHING THE ALTIMETER JUMP HUNDREDS OF FT IN BOTH DIRECTIONS. ATC CLRED ME FOR A BLOCK ALT OF A THOUSAND FT. THE JOLTS HAD EMPTIED MY PAX'S POCKETS SO THERE WAS A CELL PHONE AND PENS AND PAPERWORK FLYING THROUGH THE COCKPIT. THEN MY PAX HIT THE CEILING WITH HIS HEAD/HEADSET, HARD. THE PAX'S DOOR ALSO POPPED OPEN. MY HEADSET HIT THE SIDE WINDOW, AGAIN, AND AGAIN. WE TOOK ANOTHER HIT AND DROPPED 1000 FT. THE RADIO WAS CONSTANT CHATTER BUT ATC HAD JUST CALLED US, I RESPONDED 'MAYDAY MAYDAY MAYDAY, CESSNA NEEDS AN IMMEDIATE VECTOR TO ZZZ.' I KNOW MY STRESS LEVEL WAS EXTREMELY HIGH AS I DO NOT REMEMBER THE ENTIRE EXCHANGE OF COMS. I DO KNOW THAT I WAS USING ATC FULLY AND THE CTLR WAS VERY HELPFUL. IN ADDITION, THE OTHER PLTS ON FREQ KEPT THEIR SILENCE, WHICH REALLY HELPED. THE CTLR ISSUED A FEW LOW ALT ALERTS, BUT WE HAD DROPPED OUT OF THE BOTTOM OF THE CLOUDS INTO ABOUT 1/4 MI VISIBILITY, AND I WAS ABLE TO SPOT FAMILIAR LANDMARKS AND KNEW I COULD IGNORE MOST OF THE ALT ALERTS. THE TURB LESSENED, AND THE VISIBILITY IMPROVED. I LANDED AND CLOSED THE IFR FLT PLAN. MY PAX WAS SHAKEN BUT OKAY. BACK ON THE WX COMPUTER I SAW THE LITTLE DOCILE GREEN SPLOTCH HAD TURNED INTO A RED SPLOTCH SURROUNDED BY YELLOWS. WE WAITED OUT THE BAND OF WX, THEN WE HEADED OUT VFR WITH 10+ MI VISIBILITY. THE FLOOR OF ZZZ1 CLASS C AIRSPACE IS 2500 FT MSL. I CHOSE TO REMAIN AT 2200 FT SO AS TO NOT CROWD THE FLOOR OF ZZZ1 CLASS C, THEN CLB TO 2500 FT AND REMAIN BELOW THE CLOUDS AND ABOVE ALL OBSTACLES. LESS THAN 10 MINS AFTER DEP, I NOTICED WE WERE AT 2500 FT HEADED TO 2600 FT. I WAS 2700 FT BEFORE I GOT THE CLB STOPPED AND THE DSCNT STARTED AND STOPPED AT 2500 FT. THEN I REALIZED I WAS NOT OUT FROM UNDER ZZZ1 'C' AND I STILL HAD 3 MI TO GO. I CONTINUED THE DSCNT TO 2200 FT AND STAYED THERE UNTIL I WAS CLR OF THE AIRSPACE. ATC GAVE US DIRECT AND WE WERE ABLE TO COMPLETE THE FLT WITHOUT FURTHER INCIDENT.

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.