Narrative:

Departed ZZZ1 on IFR flight to ZZZ2; about 2 hour flight. Leveled at 7000 ft and was handed off from center to abc approach. At that point; my son (passenger) started complaining of intestinal distress and asked if we could land. GPS showed ZZZ3 as closest airport. I advised approach of our situation and they also pointed out ZZZ3; behind us by about 4 mi. We were on top of a scattered layer with good visibility underneath so I requested the visual to ZZZ3. I was cleared to descend to 4000 ft direct ZZZ3. Checking ZZZ3 ASOS; WX was about 4000 ft broken; 10 mi visibility. There were no additional warnings on the ASOS. Broke out; canceled IFR and set up for landing. There was 1 aircraft in the pattern; landed normally. No X's on runway; no equipment working anywhere; no signs or notes at pilot lounge. 2 more aircraft arrived and departed while I was there. When I called FSS to re-file; they advised ZZZ3 runway was notamed closed. The specialist contacted the city; who advised that NOTAM should be canceled. Specialist said he would have to file a report since I had landed at a 'closed' airport and asked if I had received NOTAM. Since ZZZ3 was far enough from departure and destination; I was unaware of closure. While I understand my responsibility to obtain all pertinent information prior to flight; it is unreasonable to expect that I have that information for any possible airport along a 280 NM route.

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Original NASA ASRS Text

Title: AN IFR PA32 PLT MADE AN UNSCHEDULED LNDG WITH AN ILL PAX. HE DISCOVERED THE ARPT WAS NOTAMED CLOSED WHEN HE FILED TO HIS DEST.

Narrative: DEPARTED ZZZ1 ON IFR FLT TO ZZZ2; ABOUT 2 HR FLT. LEVELED AT 7000 FT AND WAS HANDED OFF FROM CTR TO ABC APCH. AT THAT POINT; MY SON (PAX) STARTED COMPLAINING OF INTESTINAL DISTRESS AND ASKED IF WE COULD LAND. GPS SHOWED ZZZ3 AS CLOSEST ARPT. I ADVISED APCH OF OUR SITUATION AND THEY ALSO POINTED OUT ZZZ3; BEHIND US BY ABOUT 4 MI. WE WERE ON TOP OF A SCATTERED LAYER WITH GOOD VISIBILITY UNDERNEATH SO I REQUESTED THE VISUAL TO ZZZ3. I WAS CLRED TO DSND TO 4000 FT DIRECT ZZZ3. CHKING ZZZ3 ASOS; WX WAS ABOUT 4000 FT BROKEN; 10 MI VISIBILITY. THERE WERE NO ADDITIONAL WARNINGS ON THE ASOS. BROKE OUT; CANCELED IFR AND SET UP FOR LNDG. THERE WAS 1 ACFT IN THE PATTERN; LANDED NORMALLY. NO X'S ON RWY; NO EQUIP WORKING ANYWHERE; NO SIGNS OR NOTES AT PLT LOUNGE. 2 MORE ACFT ARRIVED AND DEPARTED WHILE I WAS THERE. WHEN I CALLED FSS TO RE-FILE; THEY ADVISED ZZZ3 RWY WAS NOTAMED CLOSED. THE SPECIALIST CONTACTED THE CITY; WHO ADVISED THAT NOTAM SHOULD BE CANCELED. SPECIALIST SAID HE WOULD HAVE TO FILE A RPT SINCE I HAD LANDED AT A 'CLOSED' ARPT AND ASKED IF I HAD RECEIVED NOTAM. SINCE ZZZ3 WAS FAR ENOUGH FROM DEP AND DEST; I WAS UNAWARE OF CLOSURE. WHILE I UNDERSTAND MY RESPONSIBILITY TO OBTAIN ALL PERTINENT INFO PRIOR TO FLT; IT IS UNREASONABLE TO EXPECT THAT I HAVE THAT INFO FOR ANY POSSIBLE ARPT ALONG A 280 NM RTE.

Data retrieved from NASA's ASRS site as of January 2009 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.