Hello, I have the British trawler "Active" (185 grt) sunk by an airborne torpedo, on 18/12/1939, NNE from Rattray Head.
During WW1:
On 9/09/1916 three Aircraft of 1. Seefliegerabteilung from Zeebrugge attacked a convoy in the Thames estuary, sinking the steamer "Storm of Garncy".
The steamers "Gena" and "Kankaree" were sunk by aircraft from Zeebrugge on 1/05/1917 and 15/06/1917.
There are clues about torpedoing of Turkish steamers in Marmara Sea on 12 and 17 august 1915, by Short 184s of HMS "Ben-My-Chree" but details lack.

During SCW:
On 21/07/1938, a He 59 of AS/88 torpedoed and sank the British Steamer "Thorpeness" (4.798 grt), 1 nm from Valencia: the CO of the He 59 was Martin Harlinghausen.

Hope this helps

Fabrizio

Sources:
H. Thiele "Luftwaffe Aerial Torpedo Aircraft and Operations in WW2", Hikoki, 2004
F. Mattesini "IL Blocco aeronavale Italiano nella guerra di Spagna", www.academia.edu