Why doesn't my iPhone like yahoo answers?...?

For some reason my iPhone keeps closing down safari whenever I'm on here (for example this is the second time iv written this question out as my phone closed safari before I finished and I lost everything I typed!)

it doesn't do it at specific times like when I'm changing pages or anything, it's just like it gives up after a while and takes me back to the homescreen. It will always take me back to where I was when I open safari again but like I said above, if iv been typing something I lose everything I typed, this can be such a huge pain in the *** if iv just written a lengthy answer to a question.

Anyone know why it's doing this or how to stop it? It only does it on Yahoo Answers, it's never hapened on any other site.