Narrative:

The flight was conducted as a scheduled airline under far part 135. After obtaining the local ATIS, I related the information to the captain that the field was above takeoff minimums but based on visual observations, it appeared the field conditions would continue to deteriorate before our scheduled departure. The flight was boarded and a route clearance obtained. Upon taxi, the ground controller stated that the RVV had dropped to 1/4 mi and the RVR was reported at 1000 ft. I queried the captain concerning our legality about leaving without a suitable takeoff alternate. He assured me that none was required since the RVV was at our required minimum of 1/4 mi. I, however, noted to the captain that I thought the RVR was controling and was below the 1200 ft minimum our operation specifications required. The captain disagreed and stated that the RVV satisfied the requirement. Being new to this company and being very junior to this captain, I felt that I was in error and sided with the captain's decision. The flight departed without incident and was uneventful. After the conclusion of the scheduled shift, I researched the situation more carefully and found that we had not met the required takeoff criteria. The seniority of the captain made it difficult for me to fully express my concerns and use the proper resources to find the correct answer. While I did receive training in cockpit resource management during my new hire period, it is evident that crew communications still need to be improved. Had I asked the captain for 3 mins at the end of the runway to consult the proper reference, it would have certainly saved us both a lot of embarrassment.

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Original NASA ASRS Text

Title: TKOF WITHOUT TKOF ALTERNATE.

Narrative: THE FLT WAS CONDUCTED AS A SCHEDULED AIRLINE UNDER FAR PART 135. AFTER OBTAINING THE LCL ATIS, I RELATED THE INFO TO THE CAPT THAT THE FIELD WAS ABOVE TKOF MINIMUMS BUT BASED ON VISUAL OBSERVATIONS, IT APPEARED THE FIELD CONDITIONS WOULD CONTINUE TO DETERIORATE BEFORE OUR SCHEDULED DEP. THE FLT WAS BOARDED AND A RTE CLRNC OBTAINED. UPON TAXI, THE GND CTLR STATED THAT THE RVV HAD DROPPED TO 1/4 MI AND THE RVR WAS RPTED AT 1000 FT. I QUERIED THE CAPT CONCERNING OUR LEGALITY ABOUT LEAVING WITHOUT A SUITABLE TKOF ALTERNATE. HE ASSURED ME THAT NONE WAS REQUIRED SINCE THE RVV WAS AT OUR REQUIRED MINIMUM OF 1/4 MI. I, HOWEVER, NOTED TO THE CAPT THAT I THOUGHT THE RVR WAS CTLING AND WAS BELOW THE 1200 FT MINIMUM OUR OP SPECS REQUIRED. THE CAPT DISAGREED AND STATED THAT THE RVV SATISFIED THE REQUIREMENT. BEING NEW TO THIS COMPANY AND BEING VERY JUNIOR TO THIS CAPT, I FELT THAT I WAS IN ERROR AND SIDED WITH THE CAPT'S DECISION. THE FLT DEPARTED WITHOUT INCIDENT AND WAS UNEVENTFUL. AFTER THE CONCLUSION OF THE SCHEDULED SHIFT, I RESEARCHED THE SIT MORE CAREFULLY AND FOUND THAT WE HAD NOT MET THE REQUIRED TKOF CRITERIA. THE SENIORITY OF THE CAPT MADE IT DIFFICULT FOR ME TO FULLY EXPRESS MY CONCERNS AND USE THE PROPER RESOURCES TO FIND THE CORRECT ANSWER. WHILE I DID RECEIVE TRAINING IN COCKPIT RESOURCE MGMNT DURING MY NEW HIRE PERIOD, IT IS EVIDENT THAT CREW COMS STILL NEED TO BE IMPROVED. HAD I ASKED THE CAPT FOR 3 MINS AT THE END OF THE RWY TO CONSULT THE PROPER REF, IT WOULD HAVE CERTAINLY SAVED US BOTH A LOT OF EMBARRASSMENT.

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.