The longerons are the long, molded lips that act as the canopy drip rails and seals. I am told that this is the ONLY precision molded longeron with drip rails in the kit industry. Later in the next section, the longerons will be covered with duct tape and used as molds to for the canopy lip seals. This was a "no-brain'er" process and worked out very well. The sections of the longeron just above the main gear and roll-over structure are packed with dry-micro and covered with BID to increase the strength of these areas.
The picture above shows the longerons being held in position with temporary rivets called "Clecos." The molded structure fits snugly into the molded lip on the fuselage and is bonded with wet flox. 3-plys of BID are applied to the underside of the longeron onto the inner fuselage skin. This is a VERY stiff structure and can easily support the pilot's weight while getting in and out of the aircraft.
Another wonderful innovation is the addition of silicon-carbide to the molded surface of the longeron. This increases the hardness and scratch/chip resistance of the upper surface of the longeron. Remember, the longerons will be climbed over by both the pilot and passenger everytime they get in or get out. Now that is thinking ahead!