"I know in 11 years, we've never been able to find these weapons that are supposed to have been found."
Does it mean in 11 years they are never going to be able to find the weapons they will need to have found? If so, would the use of the present perfect be conveying a certain connotation?
ostap, you submitted this question less than three hours after I wrote, in another of your threads, "You have been a member of this forum long enough to know that the more context we have, the more satisfactory the answer is likely to be". What is going on?
It's a bit of a mess, but the eleven years is up to now, and they have managed to locate the weapons that are supposed to have been detected or found IMO.