PLT OF SMA MADE NIGHT TOUCH AND GO AT ARPT; THOUGHT IT WAS ASH BUT MAY HAVE MADE THE TOUCH AND GO AT MHT.

Narrative

ANOTHER PLT AND I TOOK OFF FROM NASHUA; NH; (ASH) JUST BEFORE THE TWR AT NASHUA CLOSED FOR THE NIGHT. WE INTENDED TO ENJOY A BEAUTIFUL EVENING; AND TO SEE IF A NEWLY REPAIRED DOOR AND AUTOPLT COUPLER WAS WORKING PROPERLY. WE FLEW W TO KEENE (EEN) THEN TRACKED E TO ASH. ALL SYS APPEARED NORMAL EXCEPT WE WANTED TO SEE THE COUPLERS WORK ON A LOC. WE THEREFORE LINED UP WITH MHT'S RWY 35 TO TEST; AND ALL WORKED FINE; SO WE DECIDED TO GO NASHUA FOR A TOUCH-AND-GO. WITH ALL THE TURNING AND LOOKING AT NAV READOUTS; WE FOUND OURSELVES MOMENTARILY DISORIENTED WITH RESPECT TO GEOGRAPHY; BUT WE QUICKLY LOCATED ASH AND DID THE TOUCH-AND-GO. DURING THE DOWNWIND; WE TALKED WITH OTHER ASH TFC ON TWR FREQ; AS IS DONE WHEN THE TWR IS CLOSED. WE SPOTTED TFC AHEAD OF US LNDG; AND OTHER TFC ANNOUNCED THAT THEY HAD SPOTTED US. DURING THE ACTUAL TOUCH-AND-GO; I WAS PRIMARILY OCCUPIED WITH ASSURING SPACING WITH THE TFC WHO HAD LANDED AHEAD OF ME AND WAS CLRING AT THE END OF THE RWY. I WAS NOT REFING MY INSTS; BUT WAS MOSTLY CONCERNED WITH TFC. WE COMPLETED THE TOUCH-AND-GO; THEN DEPARTED THE AREA TO FLY FOR AWHILE; TO ENJOY THE EVENING AND CHK A FEW MORE APCH MODES; ETC. (THIS WAS WHY I BROUGHT ALONG ANOTHER PLT. I WAS GOING TO BE HEADS DOWN FROM TIME TO TIME; AND I'M NEW TO THIS AREA; SO ANOTHER SET OF EYES WHO KNEW THE AREA WOULD BE USEFUL AND SAFE.) WE DECIDED TO RETURN TO ASH AND LANDED WITHOUT INCIDENT. WHY AM I WRITING YOU? BECAUSE I'VE THE VERY UNCOMFORTABLE FEELING THAT THE TOUCH-AND-GO WASN'T AT NASHUA! WHEN WE FULL STOPPED AT ASH; WE REMARKED HOW IT LOOKED DARKER THAN WHEN WE TOUGH- AND-GO'ED. WITH ALL THE TFC LOOKOUT; I NEVER REALLY NOTICED; BUT I BELIEVE WE MAY HAVE INADVERTENTLY LANDED AT ANOTHER ARPT; MAYBE MANCHESTER; WHOSE TWR WOULD BE WHERE NASHUA'S IS IN RELATION TO THE RWY; ETC. DURING THE TOUCH-AND-GO; I WAS TALKING TO NASHUA TFC; AND SPOTTED TFC ANNOUNCING THEMSELVES; AND WAS SPECIFICALLY SPOTTED BY ANOTHER NASHUA TFC PLT -- ALL INDICATIONS WERE THAT EVERYTHING WAS NORMAL; UNTIL WE CAME BACK TO NASHUA TO LAND. IF I LANDED AT MANCHESTER; THEN I INADVERTENTLY INVADED THEIR ATA; AND DID A TOUCH-AND-GO ON THEIR RWY WITHOUT TALKING TO TWR! ALTHOUGH THE TOUCH-AND-GO WAS COMPLETELY SAFE AND DIDN'T THREATEN TFC SPACING; ETC; IT WOULD STILL BE A GROSSLY UNPROFESSIONAL ACTION.