Narrative:

After starting both engines and doing the morning run-ups, the captain noticed that the #1 fuel psi caution light came on. After discussing this situation with captain, he went to call company. Upon his return to aircraft he told me that the company said that it could be MEL'd. This didn't seem right to me, but I said nothing. After deferring the item with the control and MEL numbers the company gave us we departed for pit. During the flight I called our times into operations and was advised to call dispatch upon arrival at pit. Upon doing so, we were informed that the MEL relief was mistakenly given to us and was relief for a DH7, not a DH8. So, in effect, we flew the aircraft in revenue flight under an indication problem that had no MEL. We were in a hurry (flight crew and flight control). Although not directly required, we should have verified MEL relief in our own manuals. My disregard of my own first intuition that this was not MEL-able was a contributing factor.

Related reports:

Google
 

Original NASA ASRS Text

Title: A DH8 FLC DEPARTED WITH A FUEL PRESSURE INDICATION IMPROPERLY PLACED ON THE MEL. THE MISTAKE WAS DISCOVERED AFTER-THE-FACT AND THE FLC WAS NOTIFIED BY DISPATCH UPON THEIR ARR AT THE DEST.

Narrative: AFTER STARTING BOTH ENGS AND DOING THE MORNING RUN-UPS, THE CAPT NOTICED THAT THE #1 FUEL PSI CAUTION LIGHT CAME ON. AFTER DISCUSSING THIS SIT WITH CAPT, HE WENT TO CALL COMPANY. UPON HIS RETURN TO ACFT HE TOLD ME THAT THE COMPANY SAID THAT IT COULD BE MEL'D. THIS DIDN'T SEEM RIGHT TO ME, BUT I SAID NOTHING. AFTER DEFERRING THE ITEM WITH THE CTL AND MEL NUMBERS THE COMPANY GAVE US WE DEPARTED FOR PIT. DURING THE FLT I CALLED OUR TIMES INTO OPS AND WAS ADVISED TO CALL DISPATCH UPON ARR AT PIT. UPON DOING SO, WE WERE INFORMED THAT THE MEL RELIEF WAS MISTAKENLY GIVEN TO US AND WAS RELIEF FOR A DH7, NOT A DH8. SO, IN EFFECT, WE FLEW THE ACFT IN REVENUE FLT UNDER AN INDICATION PROB THAT HAD NO MEL. WE WERE IN A HURRY (FLC AND FLT CTL). ALTHOUGH NOT DIRECTLY REQUIRED, WE SHOULD HAVE VERIFIED MEL RELIEF IN OUR OWN MANUALS. MY DISREGARD OF MY OWN FIRST INTUITION THAT THIS WAS NOT MEL-ABLE WAS A CONTRIBUTING FACTOR.

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.