'no þy ær fram meahte' - 'none the sooner could he [get] away', i. e. 'yet he could not get away', with the verb of motion unexpressed, as was common in Old English.
The phrase no þy ær occurs six times in Beowulf (1502b, 2081a, 2160a, 2373a, 2466a), but apparently nowhere else.