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The most important modification concerned the aircraft's propulsion system. With the installation of four Turbomeca Piméné engines, the glider was transformed into a fully-fledged jet.
The fuel tank was installed in place of the observer's seat in the centre of the fuselage.
The arrangement of the four engines at the trailing edge of the wing was tested in the wind tunnel using a model. No interference with the fuselage was observed. However, at high angles of attack, flow separations occurred outside the engine nacelles. These were considered negligible, however.
The installation of the engines was a complex task. The cowling was very tightly fitted, and managing the heat dissipation proved to be difficult. Additionally, certain components of the engines had to be repositioned to fit within the cowling.
The purpose of the intricately shaped ramp in front of the engine intakes remains unclear.
In the cockpit, engine controls and instruments were introduced. The four throttle levers were placed on the left side of the cockpit, while the gauges occupied the right side of the instrument panel.
According to the test pilots, it was very difficult to synchronize the four engine revs somewhat effectively.
Also interesting is the control stick with the cannon trigger.
The landing gear was extended and retracted using an electrical switch. Once the landing gear reached its final position, the switch had to be set to the centre position before the drive's slip clutch would burn out.
After just 13 months of construction, the N-20.2 Arbalète was ready.
The first flight took place on 16 November 1951 at 10:24, with test pilot Mathez at the controls, lasting 16 minutes. In the following months, the aircraft was flown intensively. The tuning was completed in just 10 flights, and the test programme could begin. The entire flight envelope was explored, reaching the maximum speed of 720 km/h, and all expectations were met or even exceeded.
The Arbalète was so popular that it continued to fly well beyond the end of the Aiguillon project. Only a ban from the highest government authorities brought this to an end. After a total of 91 flights and 33:27 flight hours, the aircraft was taken out of service and is now on display at the Fliegmuseum Dübendorf.
Like its predecessor, the N-20.1, the N-20.2 was a 60% scale model of the projected N-20 Aiguillon. The name Arbalète (crossbow) possibly originates from the distinctive shape of the wing spars.
The design was adapted in key areas compared to the N-20.1:
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Control cables for the elevon control system were replaced with a push-rod mechanism.
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The rudder control cables were rerouted to the left side of the fuselage.
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A differential gearbox was used to couple the rudder trim tab operation.
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Elevon trim tabs.
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Continuously symmetric wing profile.
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No flaps (trim surfaces).
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No slats.
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No tow release mechanism.
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No solid rocket at the rear.
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Modified canopy.
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Mass balancing of the elevons modified.
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Various adjustments to the landing gear mechanism and main landing gear attachment.
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Dunlop main landing gear wheels with disc brakes.
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Wing ribs constructed in stringer design instead of solid material.