DESCRIPTION OF RELATED ART Cockpit doors, such as those currently provided by the aircraft manufacturers such as Boeing, Airbus, Canadair and various others are currently constructed of lightweight paper honeycomb materials. This construction provided the necessary frangibility required to satisfy instantaneous pressure equalization between the cockpit and cabin in the event of a decompression event, such as a bird strike to a cockpit window. Although this lightweight construction has performed its intended purpose as an easily-overcome barrier during a decompression event, this has also provided very little in the form of security to the aircraft flight deck and its crew.

As a result of increasing air rage incidents and more importantly the tragic events of September 11, the immediate need for securing the flight deck has now been recognized and mandated by the F. A. A. and I. C. A. O. What is needed, therefore, is a cockpit door constructed of lightweight materials with sufficient strength to provide anti- ballistic protection up to NIJ Level Illa (National Institute of Justice) and impact/intrusion resistance suitable to restrain a large human or accelerating drink cart. This impact energy has been determined to be 300 Joules and a suitably enhanced door will be capable of withstanding numerous blows to various pre-determined locations including those deemed to present a potential vulnerability.

Similarly, the anti-ballistic performance of the door will be sufficient to withstand numerous ballistic impacts at various locations and angles including gaps, seams and other areas of perceived vulnerability.

In addition to and of equal importallçe, ViU"Iy"enhanced anti-ballistic and intrusion resistances, the door has to provide for instantaneous pressure equalization.

Instantaneous for the purpose of this requirement is defined as providing a method, or intrinsic design characteristic that allows for pressure equalization between the flight deck and cabin within 15 to 25 milliseconds. The inability to provide equalization between the flight deck and cabin compartments within this time span will results in excessive loading of surrounding structures such as floorboards, bulkheads, and monuments sufficient to exceed the design limits and result in a catastrophic structural failure.

II. BACKGROUND ART Refer to Drawings attached.

III. DISCLOSURE OF INVENTION Summary The present invention relates to a lightweight cockpit door that has proven anti- ballistic performance and intrusion resistance in accordance with FAA AC# AC25.795-Z, which incorporates NIJ Level Illa requirements.

The lightweight cockpit door is constructed with opposing laminated Nomex honeycomb panels of varying thickness and densities that encapsulates a proprietary high-performance, anti-ballistic composite layer (refer to provisional patent application 60/327,684 filed on October 6,2001) (Anti-ballistic Sheet). This barrier has a weight of 0.9 pounds per ft2. The door is framed with a lightweight, high performance composite laminate frame that provides enhanced stiffness and ease of assembly.

The door has integral venting architecture that have been thoroughly tested to satisfy the pressure equalization requirements necessary to avoid catastrophic structural failure of surrounding structures.

This unique proprietary integral vent architecture provides for continuous pressure equalization between compartments while also providing ballistic and intrusion protection.

The door panels and frames äre JUe U Ubllly 1n adhesive bonding and fixtured until suitably cured. The gaps and seams are protected using a 1"wide overlay of anti- ballistic material supported at the gap by a composite laminate channel. The door (s) are attached and supported on one side by a continuous hinge that is attached using composite bonded inserts.

The door is locked using either an electromagnetic lock or electronic solenoid dead bolt. The method of lock control is via an integrated numeric keypad control panel on the cabin side and cockpit pedestal located override control.

A 30 to 60 second delay after the proper code has been entered during which an audible and visual alert will be provided to the flight crew, will allow sufficient time for the crew to either override the entry request or allow entry of the requestor.

A cockpit-side, removable emergency egress provision has been integrated into the design and can be located in the upper or lower door areas. Some aircraft have an observer seat in the flight deck aisle area and for these aircraft, it is necessary to located the egress panel in the upper area of the door as the observer seat would otherwise obstruct emergency egress through the lower door area.

IV. BRIEF DESCRIPTION OF DRAWINGS A = Ballistic Sheet Core Material B = Remotely Activated Locking Mechanism C = Integral, offset, anti-ballistic, continuous pressure equalization vent feature D = Electronic, spring-loaded solenoid dead bolt latch V. BEST MODE FOR CARRYING OUT INVENTION The best mode for carrying out this invention is to have a shop or facility that is equipped with specialized equipment necessary to fabricate and process advanced composite materials. It is further recommended that suitably trained personnel are employed of varying disciplines necessary to accomplish composite laminate lay-up, cutting, adhesive bonding, and blueprint reading. Once the above-referenced equipment and personnel are gathered, the detailed design and assembly drawings along with the process guidelines incorporate information sufficient for these personnel to fabricate and assemble the cockpit door assembly.

Vl. INDUSTRIAL APPLICABILI i r This invention is specifically applicable to aircraft including but not limited to: (1) Commercial Aircarriers (2) Commercial Airfreight and Cargo Carriers (3) Regional/Commuter Airlines (4) Charter and Fractional Ownership Aircraft (5) Private and Corporate Aircraft (6) Military Transport Aircraft (7) Any manned flying machines that are equipped with a separate cockpit and cabin area that could be possibly overtaken and used as a weapon.