Upon landing at airport after tower was closed, noted snowplows adjacent to runway.

Attributes
ACN	134586
Time
Date	199001
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : mht
State Reference	NH
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	landing other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : commercial pilot : atp
Experience	flight time last 90 days : 240 flight time total : 34000
ASRS Report	134586
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial pilot : atp
Experience	flight time last 90 days : 230 flight time total : 10000
ASRS Report	134577
Events
Anomaly	other anomaly other
Independent Detector	other other : unspecified
Resolutory Action	other
Consequence	faa : investigated
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other
Situations
Airport	procedure or policy : unspecified

Narrative:

After I landed at mht I received a call from an unidented person asking if I had called 121.3 15 mins out, as requested earlier in the flight. If they check their tapes they will find that I did. I think the communications system failed and we were cleared for our approach while the snowplows were just completing their work. We saw no snow equipment when we landed. Mht tower closes at 2300 local. Callback conversation with reporter revealed the following: reporter states, I received a message on acar's to call ZBW 15 mins before landing at mht, no reason specified. I did call the center and they acknowledged. I do not now who they would have called to alert the snowplow people. I was not aware of snowplowing in progress. Apparently one or more of the snowplow drivers was alarmed when we landed, although they were all well clear of the runway. The lady who called sounded like FAA, but would not identify herself. My company was told that I had landed west/O notifying the snowplows. Apparently center checked their tapes and the investigation seems to have died.

Original NASA ASRS Text

Title: UPON LNDG AT ARPT AFTER TWR WAS CLOSED, NOTED SNOWPLOWS ADJACENT TO RWY.

Narrative: AFTER I LANDED AT MHT I RECEIVED A CALL FROM AN UNIDENTED PERSON ASKING IF I HAD CALLED 121.3 15 MINS OUT, AS REQUESTED EARLIER IN THE FLT. IF THEY CHK THEIR TAPES THEY WILL FIND THAT I DID. I THINK THE COMS SYS FAILED AND WE WERE CLRED FOR OUR APCH WHILE THE SNOWPLOWS WERE JUST COMPLETING THEIR WORK. WE SAW NO SNOW EQUIP WHEN WE LANDED. MHT TWR CLOSES AT 2300 LCL. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: RPTR STATES, I RECEIVED A MESSAGE ON ACAR'S TO CALL ZBW 15 MINS BEFORE LNDG AT MHT, NO REASON SPECIFIED. I DID CALL THE CENTER AND THEY ACKNOWLEDGED. I DO NOT NOW WHO THEY WOULD HAVE CALLED TO ALERT THE SNOWPLOW PEOPLE. I WAS NOT AWARE OF SNOWPLOWING IN PROGRESS. APPARENTLY ONE OR MORE OF THE SNOWPLOW DRIVERS WAS ALARMED WHEN WE LANDED, ALTHOUGH THEY WERE ALL WELL CLR OF THE RWY. THE LADY WHO CALLED SOUNDED LIKE FAA, BUT WOULD NOT IDENT HERSELF. MY COMPANY WAS TOLD THAT I HAD LANDED W/O NOTIFYING THE SNOWPLOWS. APPARENTLY CENTER CHKED THEIR TAPES AND THE INVESTIGATION SEEMS TO HAVE DIED.

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.