The insurance under this policy is extended to include loss of or damage to the property insured directly caused by aircraft and other aerial devices and/or articles dropped therefrom provided that :
1. all the conditions of the policy shall apply as if they had been incorporated herein and for the purposes hereof any loss or damage as aforesaid shall be deemed to be loss or damage by fire;
2. the insurance does not cover loss or damage caused by any aircraft for which permission to land has been given by the insured.