Bell completes first SPINE structural and power-system upgrades on USMC AH‑1Z and UH‑1Y H‑1 helicopters
Bell has finished the first AH‑1Z Viper and UH‑1Y Venom H‑1 helicopters receiving full Structural and Power Improvements for NextGen Effects (SPINE) upgrades — covering airframe structure and power‑delivery systems — and the initial pair have departed Amarillo to begin flight testing under the U.S. Marine Corps programme.