The Blackburn Iris was a 1926 British biplane flying boat.
The Iris Mark V was developed into the aircraft that subsequently became the Blackburn Perth.
- R.B.1 Iris I : Prototype. One built.
- R.B.1A Iris II : The Iris I was fitted with three 675-hp (503-kW) Rolls-Royce Condor IIIA inline piston engines.
- R.B.1B Iris III : Five-seat long-range maritime reconnaissance flying boat for the RAF. Powered by three 675-hp (503-kW) Rolls-Royce Condor IIIB inline piston engines. Four built.
- R.B.1C Iris IV : The Iris II was fitted with three 800-hp (597-kW) Armstrong Siddeley Leopard III radial piston engines.
- R.B.1D Iris V : This was the final variant. Three Iris Mk IIIs were fitted with 825-hp (615-kW) Rolls-Royce Buzzard IIMS piston engines.