Issue: Sidewall of the tyre tears, and inner tube bulges out of the hole.
Damage: Given that the inner tube then clips the forks on every rotation of the tyre, this issue soon results in an explosive puncture.
Remedial action: At the time, not much. Unless you’re carrying a full spare tyre with you there’s not a lot you can do with a genuinely damaged tyre. I wondered about maybe wrapping duct tape around it (although sadly I wasn’t carrying any) or even perhaps changing the inner tube when it blew and tying the defunct tube around the damaged bit of tyre. I have no idea if this would have worked. It doesn’t seem overly likely. Equally there’s only so long you can ride direct on an inner tube before it wears through. Practically speaking all I could do was ride gently until the tube went as well, and then spend the next hour walking back pushing the bike.
Ways to avoid: Preventive maintenance would have been key here. The sidewall of the tyre looks scored and definitely weakened – I’m not completely sure how that might have happened, but checking the bike over thoroughly before riding should have brought the issue to light. I suspect that not riding my bike for a long time probably didn’t help the issue. Obviously, the next step is simply to change the tyre.