Nike Delta Force AC We have seen Nike go down the vulcanized "AC" path with several classic models, this time they're doin' it with the Nike Delta Force AC. The upper on the Nike Delta Force, originally released in 1988, stays true to the classic on this model. But, Nike changed the midsole completely with a vulcanized treatment. This new midsole definitely gives the sneaker a more "lifestyle" look. The Nike Delta Force AC is available in high and mid models.