Narrative:

Departed VFR from mht en route to bed. Was cleared at or below 2500 ft and vectored 320 degrees upon departing runway 35. I was handed to mht approach. The controller was sounding flustered and overwhelmed. I believe he confused me with another aircraft that had departed. He issued them a heading of 240 degrees and me 270 degrees. I acknowledged 270 degrees and turned to that heading. My destination was on a 175 degree heading, so after 5+ mi on 270 degrees, I transmitted 'aircraft X still on 270 degrees.' controller said 'I had given you 240 degrees.' (I believe in confusion with the other aircraft). I turned to 240 degrees. In 2-3 mins, I was issued 'on course to destination.' this was approximately 165 degrees. This course takes me practically over ash, with a class D airspace up to 2700 ft. I requested of mht approach, 'request climb to 2800 ft to remain with your control over ash airspace.' mht responded, 'altitude at your discretion.' I continued at 2800 ft, passing ash about 2-3 mi to the west and at that point just outside mht class C airspace. At that point, I observed a cap-10 converging from 10 O'clock position. I immediately pitched down and banked left to avoid, possibly entering 100 ft into ash class D airspace. After the conflict passed, I returned to 2800 ft. I am surprised mht approach never called the traffic. I believe this was a case of a somewhat overwhelmed controller trying to control B737 through C172 traffic.

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Original NASA ASRS Text

Title: A PA28 PLT HAS AN NMAC WITH A MURDY CAP-10 (A FRENCH IMPORT) 3 MI W OF NASHUA ARPT. IN HIS EVASIVE DIVE, HE MAY HAVE ENTERED THE CLASS D AIRSPACE OF ASH, NH.

Narrative: DEPARTED VFR FROM MHT ENRTE TO BED. WAS CLRED AT OR BELOW 2500 FT AND VECTORED 320 DEGS UPON DEPARTING RWY 35. I WAS HANDED TO MHT APCH. THE CTLR WAS SOUNDING FLUSTERED AND OVERWHELMED. I BELIEVE HE CONFUSED ME WITH ANOTHER ACFT THAT HAD DEPARTED. HE ISSUED THEM A HDG OF 240 DEGS AND ME 270 DEGS. I ACKNOWLEDGED 270 DEGS AND TURNED TO THAT HDG. MY DEST WAS ON A 175 DEG HDG, SO AFTER 5+ MI ON 270 DEGS, I XMITTED 'ACFT X STILL ON 270 DEGS.' CTLR SAID 'I HAD GIVEN YOU 240 DEGS.' (I BELIEVE IN CONFUSION WITH THE OTHER ACFT). I TURNED TO 240 DEGS. IN 2-3 MINS, I WAS ISSUED 'ON COURSE TO DEST.' THIS WAS APPROX 165 DEGS. THIS COURSE TAKES ME PRACTICALLY OVER ASH, WITH A CLASS D AIRSPACE UP TO 2700 FT. I REQUESTED OF MHT APCH, 'REQUEST CLB TO 2800 FT TO REMAIN WITH YOUR CTL OVER ASH AIRSPACE.' MHT RESPONDED, 'ALT AT YOUR DISCRETION.' I CONTINUED AT 2800 FT, PASSING ASH ABOUT 2-3 MI TO THE W AND AT THAT POINT JUST OUTSIDE MHT CLASS C AIRSPACE. AT THAT POINT, I OBSERVED A CAP-10 CONVERGING FROM 10 O'CLOCK POS. I IMMEDIATELY PITCHED DOWN AND BANKED L TO AVOID, POSSIBLY ENTERING 100 FT INTO ASH CLASS D AIRSPACE. AFTER THE CONFLICT PASSED, I RETURNED TO 2800 FT. I AM SURPRISED MHT APCH NEVER CALLED THE TFC. I BELIEVE THIS WAS A CASE OF A SOMEWHAT OVERWHELMED CTLR TRYING TO CTL B737 THROUGH C172 TFC.

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.