Narrative:

On takeoff from den runway 8. During takeoff roll and shortly after takeoff, a strong odor (similar to the smell of natural gas or propane) was detected in both the cabin and cockpit. The flight attendants immediately chimed the flight deck as soon as we were airborne to report this smell. Since I had flown out of den all last month and had this same smell occur several times before, we knew this wasn't something being caused by an aircraft malfunction. If I had not had previous knowledge of the occurrence of this odor and discussed it with the captain prior to takeoff, we may have returned to the field. I have reported this via as soon as possible twice before, and reiterate that a note on the flight plan or den airport page may be in order.

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Original NASA ASRS Text

Title: AN MD80 FO, PF, CORRECTLY PREDICTED THAT THERE WOULD BE A STRONG NATURAL GAS SMELL WHEN DEPARTING DEN, AS HE HAD EXPERIENCED IT DURING PREVIOUS DEPS. HE WARNED HIS CAPT OF IT AHEAD OF TIME SO THAT HE WOULD NOT CONFUSE IT WITH AN ACTUAL ACFT ANOMALY.

Narrative: ON TKOF FROM DEN RWY 8. DURING TKOF ROLL AND SHORTLY AFTER TKOF, A STRONG ODOR (SIMILAR TO THE SMELL OF NATURAL GAS OR PROPANE) WAS DETECTED IN BOTH THE CABIN AND COCKPIT. THE FLT ATTENDANTS IMMEDIATELY CHIMED THE FLT DECK AS SOON AS WE WERE AIRBORNE TO RPT THIS SMELL. SINCE I HAD FLOWN OUT OF DEN ALL LAST MONTH AND HAD THIS SAME SMELL OCCUR SEVERAL TIMES BEFORE, WE KNEW THIS WASN'T SOMETHING BEING CAUSED BY AN ACFT MALFUNCTION. IF I HAD NOT HAD PREVIOUS KNOWLEDGE OF THE OCCURRENCE OF THIS ODOR AND DISCUSSED IT WITH THE CAPT PRIOR TO TKOF, WE MAY HAVE RETURNED TO THE FIELD. I HAVE RPTED THIS VIA ASAP TWICE BEFORE, AND REITERATE THAT A NOTE ON THE FLT PLAN OR DEN ARPT PAGE MAY BE IN ORDER.

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.