Section 11 of the Aviation Act stipulates that the REGISTERED owner of an aircraft is strictly liable for any surface damage caused by the aircraft, or anything falling from it, whilst in flight, landing or taking off.
There is one exception, which is when the aircraft is bona fide leased or hired to a third party and where the registered owner plays no part in the operation of the aircraft. Then, the strict liablility switches from the registered owner to the operator.
By "strict", is meant that there is no defence, except that the registered owner can bring a TP as a co-defendant, or can claim that the plaintiff was wholly or partially to blame (unlikely in this case!). However, he cannot claim an "Act of God" was the cause, thus exonerating him. In aviation terms, God doesn't exist, I'm afraid.
So, all the plaintriff has to do is to (a) show that the loss was caused by aircraft ZS-xxx, (b) that ZS-xxx was registered to XYX and (c) what the quantum of his loss was.
You'll note there is NO mention of insurance in any of this. Whether or not you have insurance doesn't alter your liability, IF you are the registered owner of the offending aircraft. If you have insurance, mazeltov. However, oif you insurance doesn't respond ('cos you tried to save money by insuring cheaply?!!), you are still on the hook to the extent of your assets. No insurance, or insurance that doesn't pay fully or partially, is no excuse.
Now would not be a good time to find your policy had been placed in Russia, Costa Rica, Ukraine, the Phillipines, India, etc., etc.!