MD-11
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Human-Machine Interface
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural MEL / CDL
Flight Crew Overcame Equipment Problem
Aircraft; MEL
MEL states; 'After all engines are started; enter Usable Fuel on Board (UFOB) on the FMS Weight INIT Page.' After loading UFOB in either MCDU 1 or 2 it should crosstalk the UFOB to the other. The plane did NOT crosstalk this information. We got a VR mismatch message because the UFOB was not shared to the other side. I have had Tank Fuel Quantity Indication write ups before and the UFOB may or may not crosstalk to the other side. I don't know when the MD-11 stopped cross talking the UFOB to the other side but it hasn't the last 3 times I've had this problem. If the UFOB does not match each pilot's side will show/announce different VR speeds; stall speeds; limiting speed; stick shaker; etc. Some planes do not crosstalk UFOB. MEL does not say to load UFOB in both sides. Ensure all MD cross talks UFOB info or change to MEL to say ensure UFOB is loaded in both sides.
We had MEL - Number 1 main tank fuel quantity indication inoperative. It tells you to load the fuel (UFOB) after starting engines in the FMS. The problem is that it should say put in both FMS boxes; as if you don't you get VR Mismatch to start with and many to follow alerts. This can be very confusing and is a safety issue especially if the crew is new or tired; like many of us are these days. The Fuel system MEL. Put in MEL that you need to put the UFOB in both FMS.
MD-11 flight crew reported that after loading UFOB into the FMS; a Vr mismatch message was received due to the UFOB information not being shared with the other FMS.