Winter flying helmet of unknown origin (private purchase?)

Manufacturer:      Unknown (label removed)

Size:                   57

This flying helmet is constructed of dark brown leather and lined with what appears to be cat fur (!) or rabbit fur. A label must have been present on the inside of the leather strap arrangement, but has been removed. The helmet has the size "57" embossed on the inside of the ear cups but lacks any other type of markings.

No receivers or wiring are installed. In front of the earflaps on each side there are two stud fasteners the purpose of which is unknown. They might have been used to attach a face mask. 

On the back of the helmet there are two leather goggle strap retainers, secured by snap fasteners on top.

Two major modifications to the original design can be observed:

Over each ear flap the helmet sports a strip of leather with three rectangular eyelets. These can be also found on the Swiss Bücker helmet and were used to attach the oxygen mask strap hooks.

Ultimately modified for wearing with a three-strap oxygen mask, the helmet is further equipped with an adjustable strap terminating in a "U" shaped eyelet on top of the helmet

Oxygen mask Type N-521.061

Serial No. 10458

Manufactured by Huggenberger, Zurich

There are some slight differences between this mask and those worn by Swiss Morane D-3801 pilots on the b/w pictures, but the main features seem to be almost identical.

We have only scarce information about this mask, coming mainly from an instruction manual dealing with the Type Agm.40 “Munerelle” breathing apparatus, which was installed in the Morane D-3801 fighter/fighter bomber and the K+W  C-3603 fighter bomber/target tug.

Differing from the diluter demand system installed in the Swiss Messerschmitt Bf 109E-3 and Morane D-3800 fighters (which used the german Dräger mask and regulator) the Agm.40 “Munerelle” is a constant flow oxygen system. During normal operation, this system started to provide oxygen from an altitude of 10’000 feet (3500 metres) and automatically adjusting the oxygen flow with increasing altitude up to 33’000 feet (10’000 meters)

The Huggenberger mask consists of a chamois/leather lined rubber body which is sewn to a metal nose cone, giving the mask its distinctive shape. It is attached to the flying helmet by a three strap arrangement, using large elastic brown fabric straps on both sides and a narrower inflexible black fabric front strap on top.

The nose cone features a metal tag with engraved Swiss Flugwaffe equipment (type) number, mask serial number and manufacturer's name.

On order to prevent the mask from freezing, the Type N-521.061 has an integrated heating system with a two-pole plug to be connected to the aircraft’s electrical system. Oxygen from the Agm.40 regulator is provided through a narrow orange rubber inhalation tube ending in a metal connector (same type like the Swiss modified A-13A and MS-22001 masks used with Pilatus P-2 trainers, K+W C-3603/05 fighter bombers/target tugs and Pilatus PC-6 utility planes).

There is a second, black rubber hose (in this case here used as an exhalation tube?) with a black metal connector, which might indicate that the same mask could be used with a demand oxygen system as well.

The purpose of the two large turning knobs on the front plate is unknown. It seems that they simply serve as attachment screws for the wiring of the heating system.

We hope that our visitors will be able to provide more information.

We're also looking for information about the inventor of the mask. It might have been Swiss scientist Dr. Arnold Huggenberger, who patented an oxygen regulator in 1947.