I recently looked at the 1994 block of Egyptian stamps enlarged on Kjell Scharning's site and immediately realised that the flying Swallow more closely resembles a Red-rumped Swallow (Hirundo daurica) rather than the perched Barn Swallow on the same stamp. Its rump is clearly orange, and its dark crown contrasts with the orange nape and light cheeks. I'm surprised I did not notice it in 1994!