@liamdaniels: Toomes' origin is as a ruthless business man. Think Obidiah Stane but with wings. So I doubt he was in Falcon's unit. More likely he owns the business that helped to design Falcon's flight suit and wings, or is from a rival company. He did not get what the military owed him and now he is out for revenge, hence why there is a lot of Washington DC in the trailer. But that is all speculation.