A320
Dispatch Dispatcher
Situational Awareness; Confusion
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural MEL / CDL
General None Reported / Taken
Chart Or Publication; Aircraft; Procedure
I dispatched a flight from MMUN. This aircraft had MEL 25-61-01A which is a portable ELT. This particular MEL states 'May be inoperative provided no Extended Overwater operations are conducted.' Under Operation Procedures for the MEL; it further states 'Aircraft may NOT conduct extended overwater operations; however it may be eligible for limited overwater operations. In order to comply with this MEL; the flight must be routed in a way so it does not exceed 30 minutes flying time in still air with one engine inoperative; or 162 NM from the nearest  shoreline; whichever is less. I dispatched the flight. This route did not comply with the MEL and I; nor the flight crew; caught this error. I made the assumption that the aircraft was allowed to fly the standard route based on the fact that it had already flown with that MEL; and after I had spoken with the Safety Officer; confirming that it only restricted ETOPS operations. I did reference the MEL manual; but failed to read the Operations Procedures which outlines the restrictions.If it is a possibility with dispatch software; a safeguard that would prevent a flight plan from calculating if it was in violation of an MEL restriction would prevent this from happening in the future (much like how a flight plan will not calculate if you attempt to plan a non-overwater A/C on an overwater route). I have reason to believe that numerous people missed this restriction due to the fact that we are not ETOPS qualified. As a result; assumptions are made that there are no Operations Procedures; that it does not pertain to us; and they then fail to continue reading past the MEL to see if any action needs to be taken. Perhaps a notification can be incorporated into dispatch monitor when running a flight plan with this or similar MELs.  For example; a pack MEL will notify you that you must remain at a certain flight level and that there is a fuel penalty. These notifications appear on the flight summary page before taking you to the flight plan.  The note could say something along the lines of; 'Flight is restricted to limited overwater operations due MEL 25-61-01A.' Also for the Dispatch group; reiterate the importance of reading an MEL in it's entirety via training or an Ops Memo.
A Dispatcher realized after the fact that an A320 with an MEL restricting extended overwater flights; was routed with a flight segment over the Gulf of Mexico.