Science cannot help you at present. But the same experience I have gone through my life several times. I am a man from Kolkata City in India. I dreamt of train and plain accidents many times, and it became a reality. I even several times told my family members that this is the dream that I have dreamt of, and it might gonna come true. But most of the times, they forget that I had said it before, because they took it lightly, or didnt paid any attention to my words. I dreamt of a Durga Idol decorated in modern weaponry in her ten hands. The same picture was published in a daily Bengali newspaper Ananda Bazar Patrika as a front page description of their coming Puja Edition 'Desh' magazine that year. I dreamt of inland and international air-crash and train accident pictures, which were published in the news papers two three days later - exactly in the same style, as I had seen in my dream. A few month ago I dreamt of a chess-board like area, but could not make it out what was it. But I was damn sure that this was going to be an accident site - be it airoplane or train. A few days later, a foreign airoplane accident, shown in television, remembered me that the design of the aircrash site was like a chess-board because there were some construction and steps - ditto my dream. But sometimes, as you said, my dreams also fails. But as days passes, I have experienced and gathered the knowledge that there are some difference between a normal dream and the type of dreams which would have the chance of coming true. You will know that there will be some element of trance-like inward feeling while you dream of such dreams. And you can differientiate between a normal dream and a psychic one. I have not attained that much expertise till now. But I feel, if a person earnestly tries, he or she may attain that expertise to differentiate. And the most important is, how can we help people by informing in advance about the coming crashes or the crash sites ? You see, what I have seen like a chess-board area, how can I interprate it to the people near that accident site ? The least I can do is to draw a sketch of that chess-board like area, and submit it in a web site and tell people worldwide that this is the crash site what I have seen in my dream, so people, you better be aware - is there any area like this in your locality ? If the answer is yes, then please avoid risky jobs or airoplane or train journeys near that area. Well, if I see one such dream again in future, I promise, I shall write it down here in Yahoo Answers site. But, as I said, I cannot guaranty you about the result. I believe, it is a paranormal fenomena and capability, which we, a few people in the world have got - some at lower level, and some at a very higher level, whom we call a psychic. Thank you friend.