Why a Flower could not carry a spinal 4-inch gun

Could a Flower-class corvette carry a spinal 4-inch gun?

No. Recoil from a centerline spinal mounting would impose loads the small commercial-derived hull was not built to withstand.

A gun mounted along the ship's centerline would transmit recoil through a hull derived from commercial construction. The Flower's structure was never intended to absorb that load as one continuous longitudinal weapon mounting. Strengthening it enough would consume weight and internal space that the small escort did not have to spare. The existing deck gun was therefore a practical fit, while a spinal arrangement risked breaking the hull.