OK, I checked the streams. Looking at the RTT of the connection in the 3-way handshake I get about 48ms. I also see that the trace was made at the server-side. The GET request and the SSL Close Notifiy come into your server only about 100 us apart, so the client (iPad) actively shuts down the connection before waiting on a response. Also the resending of the request is done only 699 us after the first request, so it could not be a user-action. I suspect there is something on the site that does not play nice with the iOS Safari browser and makes it abort the request. Do you see the same behavior with other objects on the site?
I happens with other AJAX requests on the site as well. I still have no idea why though, it only happens with iOS devices. One thing which I suspect, is that the article page is opened via HTTP and then sends an AJAX request to addArticle via HTTPS. But what could be the problem here? Is there any more info I could provide or other idea to debug this?