Winter 2019 I bought the Alula, it has about 60 cm wingspan and is made of foam.
My first foam model. It should replace the Zagi with its miserable flight characteristics. The Alula needs some upwind to stay up. Higher altitudes are hardly possible, if altitude is converted into speed the whole energy is destroyed. Probably this is due to the rough surface and the low weight. The wings were finally glued to the fuselage, because very high forces are generated by dropping plane into air. The Alula can still be used in windy weather due to the small amount of ballast added.