The aircraft in question went off the end of R15 at E and dug about a 5m long furrow in the mud. This part of the runway is notoriously slippery when wet, a fact well known to regular BHX visitors and ATC, so it's no surprise somebody has come a cropper, it was only a matter of time. The aircraft was eventually towed out of the mire by its main gear about 90 minutes later.