The United States Government, in response to recent terrorist attacks in the United States and across the world, has implemented various regulations designed to thwart terrorists from commandeering mobile platforms such as aircrafts, busses, and subways. For example, the United States Government now requires aircrafts to include secure cockpit doors that are resistant to terrorist intrusion in an effort to prevent terrorists and otherwise unauthorized personnel from gaining access to the cockpits and controls of aircrafts.
Manufacturers now provide mobile platforms with cockpit doors that incorporate enhanced safety features to even better prevent unauthorized entry onto a flight deck or otherwise restricted area, and to comply with governmental regulations. Many manufacturers have incorporated safety features such as cockpit door frame reinforcements, bullet-proof materials, and improved cockpit door latches. Such improvements typically act in concert to provide a security system that prevents intruders from gaining access to restricted areas of the platform. Generally speaking, enhancements to the construction of the door, door frame, and latch have operated to further help prevent breaching a locked cockpit door, and thus, gaining unauthorized access to a restricted area of the mobile platform.
For mobile platforms such as busses and subway trains, cockpit door reinforcements and door latch systems adequately prevent intrusion into the cockpit of the respective platform. Increases in the strength of the materials used in construction of the cockpit door and door frame, in conjunction with a stronger latching system, are often able to withstand forces applied to an outside surface of the door and thus prevent most intruders from gaining access to a restricted area of the platform.
Cockpit door reinforcements such as enhanced cockpit doors and door frames made from stronger materials can similarly be used in protection of a cockpit of an aircraft. Such reinforcements typically restrict entry to the cockpit and therefore adequately prevent cockpit intrusion. However, while such cockpit door and door frame improvements adequately prevent access to restricted areas, conventional reinforced door latch mechanisms are not suitable for use with an aircraft due to the pressurization of aircraft cabins and cockpits.
Aircraft cabins, and thus cockpits, are pressurized due to the altitude at which most commercial aircraft fly. The cabin and cockpit pressure is maintained at a certain pressure to provide passengers and crew of the aircraft with a safe and pleasant flight. However, under certain situations, the cabin and cockpit may lose pressure and experience a “decompression” event. Forces associated with such decompression events are typically large and occur very rapidly, thereby causing the cabin and cockpit to experience structural changes.
Aircraft are required to fly with the cockpit door securely locked to prevent intrusion into the cockpit, as previously discussed. Under a cockpit decompression event, however, the cockpit door must be opened to allow venting of the cabin area and relieve the pressure on the cockpit/cabin bulkhead therein. However, due to the size and rate of the forces exerted on the cockpit door and its associated frame/support structure during a decompression event, conventional latches could jam and therefore essentially prevent the cockpit door from being opened. Such jamming experienced during a decompression event is typically not an issue for a conventional cockpit door as conventional doors are not typically equipped with a door latch and strike capable of locking the door. However, due to recent FAA regulations, door latch and door strike systems are required to maintain the cockpit door in a locked position for the duration of a flight.
Therefore, a cockpit door latch and door strike system that adequately locks a cockpit door to prevent intrusion into the cockpit during flight while still allowing for opening of the cockpit door during a decompression event, is needed.