An oxy mask bayonet is missing, but we are working on it.
GUENEAU S-00x (001/002/003)
​
The Gueneau prototype (S-00x) is a rather interesting item.
​
Unconfirmed sources claim that it was designed with the support of Intertechnique during the R&D process of the EROS MP90/91 oxygen mask and related helmet-fitted connector receivers.
​
It looks as if those helmets were planned for the Swiss and possibly American market.
​
During the mid-1980s, the Swiss AF was looking for an aircraft suitable to replace the Mirage III. Among those evaluated the Northrop F-20, Mirage 2000, F-16 and the F/A-18, the evaluation winner.
​
Due to the ever-improving performance and air combat tactics, pilots were increasingly exposed to high acceleration. As a result, according to the Dübendorf FAI (Fliegerärtzliches Institut - Aero Medical Institute), spinal disorders were increasing observed with the weight of the pilot's helmet/mask system playing an important role.
​
The FAI consequently proposed to the AF to evaluate/ purchase new lightweight helmet and mask systems, with the lowest possible weight, optimal centre of gravity and good wearing comfort.
​
During 1986, three specimens of the Gueneau prototype helmet identified as S-001/002/003 were procured.
The definition S-00x (S - Suisse?) simply identified a helmet and not the helmet’s model (unknown to date): two for flight and one for laboratory testing with the aim to provide pilots with a "Super-Leichthelm" (Super Light Helmet).
​
Evaluated on F-5 and Mirage III on ground and in flight, the helmet was fitted with an Intertechnique EROS (Équipement Respiratoires à Oxygène de Secours) MP91 type oxygen mask.
​
For more details about the evaluation, see HERE​
​
The helmet's low weight, comfort, visibility, and mobility in the cockpit were positively rated, however, several problems were also observed:
Given the peculiarity of its construction, in order to have a proper seat of the mask and earpieces it was necessary to tighten its harness a lot, creating painful pressure points. On the other hand, during long times in cockpit on the ground, with the mask worn loose for better ventilation , the helmet’s ear cups were moved away from the ear and the radio communication possibly overheard in the presence of additional external noise sources; even with the system adjusted, noise attenuation and communication quality deemed insufficient;
​
The adjustment of the mask with 3 variable suspension points (In the pictures above the RH lower oxy mask bayonet is missing, but we are working on it...) deemed difficult and time consuming, as the helmet with its 3-piece shell also not having a defined fit;
​
Suboptimal nape strap installation; awkward anti-glare visor control operation, in conflict with the (Mirage III) ejection seat operating handle.
​
In short, apart from its low weight, the prototype had no advantages and many disadvantages. In addition to those mentioned above, there were also doubts about its real ability -given its configuration -to protect against impacts. For this reason, the Gueneau S-00x evaluation was discontinued.
The visor control, which was considered cumbersome to use and could get in the way of the Mirage III upper ejection seat handle.
Visor operating arm.
EROS MP91 data label.
The visor control, which was considered cumbersome to use and could get in the way of the Mirage III upper ejection seat handle.
