In the last week I came upon a couple of great sites at which you can find aerial photos, and most importantly, early aerial photos of the Levant.
Based on a tip from David, I found the absolutely fantastic website of the German Bayern State Archives (Bayerisches Hauptstaatarchiv), which has hundreds upon hundreds of german WWI aerial photos of many parts of the Levant. The include many photos not included in the well-known collections of aerial photos put out by Dalman (1925) and Kedar (1991).
Although I could not find any photos of Tell es-Safi/Gath itself, I did find a few of the site of et-Tine, which is an Arab village which was destroyed in the Israel War of Independence in 1948, and before that served as the location of a German and British airstrip during WWI. This site, et-Tine, is located about a km to the NW of Kfar Menachem, just 4 km or so from Tell es-Safi/Gath.
Here is one of the photographs of et-Tine, courtesy of David Kennedy:
And BTW – if anyone knows of other European collections of early aerial photographs in which sites in the Levant can be seen – I’d be glad to hear about them