This Lockheed Martin kit modification is an externally serviced, flushable toilet installed in the aircraft’s cargo compartment. In addition to providing a more sanitary and easily maintained crew relief facility than the previous chemical toilet, the system is designed to prevent potential fuselage corrosion in the surrounding area.

The flush toilet is installed immediately aft of the right paratroop door. Privacy is ensured by a thermoplastic enclosure with a curtain across the front. A pushbutton switch on the back panel operates the flushing pump. When not in use, a platform provided for foot support rotates to a vertical position to keep cargo compartment access clear.

The toilet assembly with plumbing, foot platform, and curtain are installed using support structure tied to the aircraft frame. One circuit breaker and wiring are added to the aft fuselage junction box to power the flushing pump. Installation of the flush toilet requires relocation of any equipment situated on the right side of the cargo bay between FS 737 and 770. If an oxygen regulator is in the area, it is moved for accessibility from within or outside the toilet.

The aircraft’s external service panel is modified with a pressure box, referred to as the service pan, that mates with a drainage duct from the toilet’s holding tank to allow external waste removal. Air from the holding tank is vented overboard by a duct leading from the tank to a new pressure fitting in the fuselage.

The flush toilet retrofit offers a convenient, easily serviced, low maintenance crew relief facility with minimal aircraft modification.