Narrative:

At altitude of FL360 I experienced gas pains and relinquished control of the aircraft to the first officer. The first officer thought that I might be having chest pains and declared an emergency. We descended to FL300 where I relieved the gastric problem. We landed the aircraft in ZZZ where I went to the restroom for 15 mins and afterward felt fine with no further problems. To avoid any future problems of this nature; I have made adjustments to my diet. I have been flying for over 40 yrs and this has never been a problem in the past. Supplemental information from acn 790556: while cruising at FL360; the PIC told me that I had control of the aircraft. He then bent forward in his seat and grasped his stomach or chest area; I was not sure which. Fearing that it could be a heart attack I declared an emergency and requested vectors to the nearest suitable airport. As we descended through about FL310 the PIC sat upright and stated that he had passed some gas and felt better. We decided to continue on to ZZZ where he spent some time in the restroom after which he said he felt fine. He continued to feel good for the rest of the day.

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Original NASA ASRS Text

Title: A BUSINESS JET CAPTAIN EXPERIENCED GASTRIC DISCOMFORT AT CRUISE TO THE EXTENT THE FO DECLARED AN EMERGENCY AND DESCENDED TO LOWER ALT.

Narrative: AT ALT OF FL360 I EXPERIENCED GAS PAINS AND RELINQUISHED CTL OF THE ACFT TO THE FO. THE FO THOUGHT THAT I MIGHT BE HAVING CHEST PAINS AND DECLARED AN EMER. WE DSNDED TO FL300 WHERE I RELIEVED THE GASTRIC PROB. WE LANDED THE ACFT IN ZZZ WHERE I WENT TO THE RESTROOM FOR 15 MINS AND AFTERWARD FELT FINE WITH NO FURTHER PROBS. TO AVOID ANY FUTURE PROBS OF THIS NATURE; I HAVE MADE ADJUSTMENTS TO MY DIET. I HAVE BEEN FLYING FOR OVER 40 YRS AND THIS HAS NEVER BEEN A PROB IN THE PAST. SUPPLEMENTAL INFO FROM ACN 790556: WHILE CRUISING AT FL360; THE PIC TOLD ME THAT I HAD CTL OF THE ACFT. HE THEN BENT FORWARD IN HIS SEAT AND GRASPED HIS STOMACH OR CHEST AREA; I WAS NOT SURE WHICH. FEARING THAT IT COULD BE A HEART ATTACK I DECLARED AN EMER AND REQUESTED VECTORS TO THE NEAREST SUITABLE ARPT. AS WE DSNDED THROUGH ABOUT FL310 THE PIC SAT UPRIGHT AND STATED THAT HE HAD PASSED SOME GAS AND FELT BETTER. WE DECIDED TO CONTINUE ON TO ZZZ WHERE HE SPENT SOME TIME IN THE RESTROOM AFTER WHICH HE SAID HE FELT FINE. HE CONTINUED TO FEEL GOOD FOR THE REST OF THE DAY.

Data retrieved from NASA's ASRS site as of May 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.