Hi Garth - I had exactly the same thing a few years ago on my Minno when one tyre burst, then the other on the same side failed only 10 mins or so later. I'm not sure what triggered the first wheel to blow (age?) but the problem is that when the first wheel blows, the trailer remains so stable that you don't realise it has until quite a while later, by which time the tyre is completely shredded and has thrown sharp bits of steel belt all over the place, damaging the other tyre in front or behind which fails soon thereafter. The only good news is that I found you can get home fairly well (slowly and carefully) on just 3 wheels (probably not recommended practice however)