Aircraft Cabin Window Vent Hole

-

 Aircraft Cabin Window Vent Hole 

 

Aircraft cabin window provide clear visibility from cabin to outside. It is required to have opening in aircraft structure to accommodate cabin window. Commercial aircraft normally fly at high altitude to get economy benefit but this pose safety issue for passenger due low ambient pressure. Thus, aircraft pressurized for passenger comfort and safety.

 

                                          Fig 01  Aircraft Cabin Window

Due difference in ambient and cabin pressure, pressurization load act inside of an aircraft structure.  To take pressurization load effectively structure must be strong and opening in the structure should be as small as possible and stiffened around the opening for structure stability. Aircraft window are smaller in size to ensure minimum pressurization load act on window. Window opening in the structure are oval shape to prevent stress concentration points.

Aircraft window comprises two window panes called main pane and inner pane. There is additional pane called scratch pane and it is for safety reason. The use of these two panes  increase window panes reliability. Main pane installed as outer window pane in window frame and it is relatively thick and has high fatigue strength. Inner pane installed as auxiliary pane in window frame and it is relatively thin and low fatigue resistance strength. The scratch pane covers the inner pane which prevent passenger touching  the inner or outer pane. Scratch pane is window retainer part.

The outer main pane away from cabin while the inner pane next to cabin. The panes installation in  window frame such that it creates space between the both panes. The both panes are held in window frame by seal arrangement and window frame secured to aircraft body structure.


 

Fig 02 Window Construction

The outer main pane takes up the cabin interior pressure under normal operating condition.  The inner auxiliary pane is not required to take up the inner cabin pressure under normal operating condition since cabin pressure effective in the space between inner and main panes.



Fig 03 Vent Hole on Inner Window Pane




Fig 04 Vent Hole 

The space between main and inner pane connected to the interior cabin through small diameter hole on inner pane called vent hole or breather hole.Vent hole equalize pressure between interior cabin and space between inner and outer pane and also ensure cabin pressure act on outer main pane under normal operating condition .During aircraft operation if outer main pane breaks, inner auxiliary pane take interior cabin pressure load. However, in such an emergency it is necessary to assure that the particular flight can continue to its destination without a total failure of the inner window pane.





Please Follow me and Join me on Telegram there you can share your doubt.

https://t.me/joinchat/NxLqTH2cTX9hMjM1

You can also Join me Facebook Group,Link provided below.

https://www.facebook.com/groups/304288677920172/?ref=share


Join us on instagram link below

https://www.instagram.com/invites/contact/?i=1tv1l3w2dcogj&utm_content=m7ttk5x


Youtube Channel

https://www.youtube.com/channel/UCwfz-cO2H3k8tnA_CMrMKtw

 

 


Comments

  1. UnknownJune 26, 2021 at 10:53 PM

    Beautifully explained in detail & simple to understand the concept.
    These small yet important technical concepts are really helpful.

    ReplyDelete

Post a Comment

Popular posts from this blog

Flap and Slat Wing Tip Brake Location

-
Image
Why Wing Tip Brake of Flap and Slat Installed at outboard of wing? The function of wing tip brake to hold and stop rotation of flap/slat transmission shaft when slat/flap control computer sense asymmetry, uncommanded or runways condition of flap/slat. Wing tip brake(WTB) work similar to pressure  off brake(POB).Pressure off brake installed in power control unit (PCU) and wing tip brake separately placed at wing tip. The contraction of WTB and POB similar to brake of an aircraft. As the brake has stator, rotor and piston housing similarly we have stator, rotor and piston housing  in WTB and POB . Pressure Off Brake                                                               Fig 1  Pressure  Off Brake POB consist of friction disc, spring and piston assembly for actuation of spring. When hydraulic pressure avai...
Read more

Aircraft Entry Door Scuff Plate

-
Image
Aircraft Entry Door Scuff Plate An aircraft structure carry different load during different phases of flight.The modern aircraft structure design are  based on semi monocoque construction. In semi monocoque construction  all structural member of structures such as stringers,frame ,bulkhead and skin carries the loads.Fuselage skin is the principle load carrying member of semi monocoque construction design.All the loads acting on fuselage is  transferred from skin to internal member of fuselage structure.The integrity of fuselage skin is important for transferring the load efficiently from fuselage skin to internal member of fuselage structure.         Fig 01  Entry Door Scuff Plate Fuselage has number of opening in the fuselage structure for window,door,servicing panels,inspection access hole etc for access and servicing.Passenger/cargo door opening for passengers boarding/deboarding, cargo loading / off loading and inspection access hole for carry...
Read more

Aircraft Engine Nacelle Strake

-
Image
  Engine nacelle strake is vortex generator which enhance aerodynamic performance of an aircraft. It is mounted on engine nacelle. Encircled part in this picture is engine nacelle strake.Many aircraft engine have strake only one side and that will be on inboard of nacelle but few aircraft have strake on both the sides. Fig 01 Engine Nacelle Strake  Fig 02 Strake View from Cabin The purpose of nacelle strake is to generate vortex which energize the low energy airflow over the wing when aircraft operating at high angle of attack and low speed condition such as takeoff and landing phase of flight. We have seen many modern aircraft have their engine mounted beneath of wing and inlet of engine nacelle  forward of wing leading edge. There are many advantages of installing engine below the wing but there are some disadvantage and one of the disadvantages is engine nacelle /wing assembly interaction which disturb the airflow over the wing and it affect the lift production capabil...
Read more