In the post-WWII era, the Swiss state aircraft manufacturer EFW initiated the N-20 Aiguillon project to develop a domestic multi-role jet fighter. The design featured a tailless configuration with four turbojet engines integrated into the wings, aiming for a speed of Mach 0.9 and a 15-kilometer service ceiling.
The project required advanced engines capable of supercirculation to allow operations from 250-meter short runways. Due to the lack of suitable existing engines, EFW developed the SM-01 Swiss Mamba, based on the British Armstrong Siddeley Mamba, but struggled with insufficient thrust and technical vibrations.
Development included several prototypes, such as the N-20.1 glider and the N-20.2 Arbalète, which used French Turbomeca Pimene engines. Despite successful flight tests of the sub-scale prototypes, the primary N-20 program faced significant delays and rising costs associated with the engine development.
By 1952, the Swiss government canceled funding for the N-20 project, opting to purchase licenses for British DH-112 Venom fighters instead. Subsequent attempts by EFW to continue development with simplified designs were prohibited by the Ministry of Defense, leading to the project's closure.
