Abstract:
A passenger aircraft cockpit safety system, consisting of a strong, bullet resistant door and wall, both equipped with a peephole and a shielded window opening. The cockpit wall and the closed door allow for a free air exchange between passenger cabin and the cockpit.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates to a wall and a door arrangement between passenger cabin and pilot compartment in a passenger aircraft, and it particularly relates to safety elements in this area. In the past, air travel was quite safe and an open door to a pilot cockpit was customary. Recent terrorist attacks against pilots and hijacking of airplanes alarmed the general public and created a great concern for pilots, who are now working in to dangerous environment. Existing cockpit doors cannot be strengthened and locked because they have to open automatically to balance air pressure between passenger cabin and a pilot cockpit in certain situations. This invention provides a strong cockpit door with an inside locking system, and it also allows for a free airflow between passenger and pilot compartments. Also, a cockpit wall has the same airflow arrangement. 
     BRIEF SUMMARY OF THE INVENTION 
     An object of this invention is to provide a safe environment for pilots in the cockpit, thus letting them to concentrate on their main task, piloting the airplane. This is achieved by door, locked by pilots from inside, and also by providing the door with plurality of special strips, allowing for free airflow between passenger and pilots compartments, but blocking an outside view and eventual bullets. Also, a peephole and a shielded window opening are provided for observation, and the window could be used for a crew contact, for food and beverage supply and for use of weapon in emergency. This free airflow is very important when airplane is suddenly changing altitude. The door should be built of strong materials: for example, steel, other metals, or plastics. In order to isolate pilots from passengers, a cockpit door could be completely removed and another outside door could be built for pilots. In such a case, the wall between pilots and passengers should have a plurality of special strips for allowing a free airflow. This invention is providing such a safety door and a safety wall for an airplane cockpit. 
    
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
     FIG. 1 is a diagrammatic front view of a cockpit door according to the invention from the cockpit side. 
     FIG. 2 is a side view of the cockpit door from the right side. 
     FIG. 3 is a partial enlarged cross section view of the door from FIG. 1, taken along line  1 — 1 . 
     FIG. 4 is a partial enlarged view of part of the door from FIG. 1, taken along line  2 — 2 . 
     FIG. 5 is a partial enlarged view of a part of the door from FIG. 2, taken from direction A. 
     FIG. 6 is a partial enlarged cross section of the door from FIG. 1, taken along line  3 — 3 . 
     FIG. 7 is a partial enlarged cross section of the door from FIG. 1, taken along line  4 — 4 . 
     FIG. 8 is a partial enlarged cross section of the door from FIG. 1, taken along line  5 — 5 . 
     FIG. 9 is a front view of a cockpit door with plates from the cockpit side. 
     FIG. 10 is a partial enlarged cross section of the door from FIG. 9, taken along line  6 — 6 . 
     FIG. 11 is a partial enlarged cross section of the door from FIG. 9, taken along line  7 — 7 . 
     FIG. 12 is a partial enlarged cross section of the door from FIG. 9, taken along line  8 — 8 . 
     FIG. 13 is a partial enlarged cross section of the door from FIG. 1, taken along line  5 — 5 . 
     FIG. 14 is a front view of a cockpit wall from the cockpit side. 
     FIG. 15 is a front view of a cockpit wall with plates from the cockpit side. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     This invention is an improvement to safety arrangement of an airplane front area between a passenger cabin and a pilot cockpit. The present invention will now be described in details with reference to accompanying drawings. 
     FIG. 1 shows a front view of a cockpit do or having two wings, a right wing  1  and a left wing  2 . There is also shown a peephole  3 , a window opening  4 , a window shield  5 , a window base  18 , an upper lock  14  with its guide  16  and with a locking bar  17 , a U-shaped strip  12 , a Z-shaped strip  13 , S-shaped strip  23 , a V-shaped strip  24 , a medium lock  8  with its guides  9  and a locking bar  10 , a frame bar  11 , a frame  7 , door hinges  6 , and a lower lock  15  with its guide  16  and a locking bar  17 . The window shield  5  is shown in a closed and locked position. Locking the door is achieved by sliding bar  10  to the left, moving up the upper bar  17 , and by sliding down the lower bar  17 . In order to open the door, the locking bars have to be moved in the opposite directions, and the door wings  1  and  2  should be turned 90 degree to inside of the cockpit on their hinges  6 . The peephole  3  allows the crew to see activity in the passenger cabin without opening the window shield  5 . The strips could be positioned on the cockpit door in a vertical, horizontal, slant, or in any other position. 
     FIG. 2 shows the same parts as FIG. 1, but the window shield  5  is shown in an open position. The window opening  4  allows for a crew communication, for supply of food and beverages, and also for using weapon by pilots in an emergency situation. Portion of the upper hinges  6  are cut off in order to show the window shield  5 . 
     FIG. 3 shows a partial enlarged cross section of the left wing  2  and also a cross-section of a cockpit wall  35 , a frame  7 , and a number of Z-shaped strips  13 . Both sides of each strip overlap the other sides of immediately adjacent strips. The shape of the strips  13  and their arrangement allow for a constant free airflow between both sides of the door, in both directions. 
     FIG. 4 shows a partial cross section of the right door wing  1  and also a cross section of cockpit wall  35 , a frame  7 , a number of U-shaped strips  12 . Both sides of each strip overlap the other sides of the immediately adjacent strips. 
     There could be many different shapes of strips, with different cross sections, but they cannot be flat. They have to be curvilinear in cross section. 
     FIG. 5 shows a window opening  4 , a window shield  5 , a shield lock  19 , with shield lock guides  2  and a locking bar  22 . Also, a window base  18  is shown with its locking bar guide  20 . Locking and unlocking of the window shield  5  is possible by moving the locking bar  22  to left or right. The window shield  5  opens by rotating to the cockpit side, as shown on FIG.  2 . 
     FIG. 6 shows it partial cross section of the door wings  1  and  2 , a low lock guide  16 , and a locking bar  17 . The edge of the door wing  1  is blocking movement of the door wing  2  to the cockpit direction. 
     FIG. 7 shows a partial enlarged cross section of the door wing  2 , the cockpit wall  35 , a frame  7  and a number of S-shaped strips  23 . The both sides of the each strip are overlapping the other sides of next adjacent strips. 
     FIG. 8 shows a partial enlarged cross sections of the door wing  1 , the cockpit wall  35 , a frame  7 , and a number of V-shaped strips  24 . Both sides of the each strip overlap the other sides of immediately adjacent strips. 
     FIG. 9 shows a front view of a cockpit door with plates, having two wings, a right wing  25  and a left wing  26 . There is also shown a peephole  3 , a window opening  4 , a window shield  5 , an upper lock  14 , a medium lock  9 , a lower lock  15 , a frame  7 , hinges  6 , plates  27 ,  28 ,  29  and  30 , openings  32 , strips  31 ,  33 ,  34 , and  38 . The strips could be positioned in a vertical, slanted (i.e. diagonal), horizontal, or in any other position. A side view of the door is very similar to the door from FIG. 2, except for strips and openings, which are shown on cross sections FIGS. 10-12. 
     FIG. 10 is a partial enlarged cross section of the door from FIG.  9  and also of the wall from FIG.  15 . FIG. 10 shows a door wing  2 , a wall  36 , a frame  7 , plates  28  and  28 , opening  32 , and strips  31  and  33 . The strips of the plate  27  are blocking a direct linear view from openings of the plate  28 , and the strips of the plate  28  are blocking a direct linear view from openings from the plate  27 . The arrangement assures no outside visibility to the cockpit and it also makes these doors and walls bulletproof. 
     FIG. 11 shows the door wing  26 , a wall  36 , a frame  7 , plates  27  and  29 , opening  32 , and strips  31  and  34 . Otherwise, this arrangement is similar to the one shown on FIG.  10 . 
     FIG. 12 shows the door wing  25 , the wall  36 , the frame  7 , plates  28  and  30 , opening  32 , and strips  33  and  38 . Otherwise, this arrangement is similar to the one shown on FIG.  10 . 
     FIG. 13 shows the door wing  1 , the wall  35 , the frame  7 , and two rows of strips  37 . The strips of a first row are blocking perpendicular view through openings of a second row, and the strips of the second row are blocking perpendicular view through openings of the first row. 
     FIG. 14 shows a cockpit wall  35 , a peephole  3 , a window opening  4 , a window shield  5 , a frame  7 , an opening  32 , and strips  12 ,  13 ,  24 , and  37 . The strips can be arranged on a wall in a vertical, horizontal, slanted (i.e. diagonal), or in any other position. For cross sections of the cockpit wall, see FIGS. 3-5,  7 - 8 , and  13 . 
     FIG. 15 shows a cockpit wall  36 , a peephole  3 , a window opening  4 , a window  6 , a shield  5 , a frame  7 , an opening  32 , and strips  31 ,  33 , and  34 . The strips can be arranged on a wall in a vertical, horizontal, slanted or in any other position. For cross-sections of the cockpit wall  36 , see FIGS. 10-12.