Similarly, a simple steel tube structure in the nose of the fuselage was used to support the engine; detachable panels across the cowling provided access to most of the engine's areas for inspection or adjustment purposes. Installed underneath the fuselage, the liquid-cooled radiator has a rectangular opening to its aft; this is covered by a hinged flap via which the pilot was able to actively vary the cooling level. An atypical feature for the era was the use of Tungum alloy pipes throughout the cooling system.