Yes, should be Sykes whom I understand that Churchill disliked intensely. Sykes was a bit odd to some and unable to handle himself politically, so Trenchard took a lot of his ideas and credit. Henderson is a close second.
There are so many more than Trenchard - Smuts, Henderson, Sykes, Maitland, Groves, Paine and even Churchill with his insistence on the formation of the Air Ministry. It should really be “Fathers of the Royal Air Force” in my humble opinion.