Aircraft Rain Gutter

- May 30, 2021

What we call encircled metal stripe object on below Picture?

Fig 01 Rain Gutter

Well, It is called rain gutter.The Purpose of rain gutter is to prevent drip of rain water, condensation water , de-icing fluid on passengers or crew during embarkation or de-embarkation .It also keeps water out of the plane interior,where floors can become slippery.

Fig 02 Rain Gutters Installed Position

Rain Gutter installed on passenger aircraft are usually fixed above cabin door on fuselage section.The size of rain gutters is limited due to aerodynamic drag.Thus, in heavy rain condition rain gutter may fill and overflow over the door area.To Allow rapid drain of water, Rain gutters usually installed in inclined position.Aircraft forward door rain gutters inclined downward in forward direction so that all water drain toward nose of the aircraft.Aircraft aft door rain gutters inclined downward in rear direction so that all water drain toward tail of the aircraft.

Similar to Rain gutter metal stripe we can also find, Metal stripe at two locations on aircraft.One on APU access door and other one on wing lower surface near wing tank vent.

The metal stripe on APU access door called fluid barrier and stripe on wing lower surface known as wing fence or drip fence.

APU Access Door Fluid Barrier;

Fig 03 Fluid Barrier Metal Stripe

The reason of installing fluid barrier on APU access door is to prevent build up of an ice in APU intake, When aircraft on ground in cold weather condition.

When aircraft on ground and outside air temperature between 0 deg.C and 2 deg.C or Freezing Rain conditions, the water could run across the aircraft body converge to the air intake and can be ingested by air intake.This could lead to an ice building.This ice could clog the APU air inlet protection screen and duct of the cooling fan which could lead to APU high oil temperature auto-shutdown or APU bleed fault.Fluid barrier stripe on APU access door divert rain water away from APU air intake which ultimate prevent formation of ice in air intake.

Wing Fence or Drip Fence on Wing Lower Surface;

Fig 04 Drip Fence OR Wing Fence

Aircraft wing fuel tank have vent which is usually located lower surface of wing,these allow air to escape from the fuel tank when aircraft is refuelled and air get inside of tank when fuel defuelled or use by engines.Wing tank vent actually equalizing pressure between tank and atmosphere.

Various measure taken to prevent leakage of fuel via these vents,however some leakage may occur.

This leakage can be due to overflow of fuel in vent surge tank.To prevent fuel leakage migration to hot surface on the aircraft such as the engine or brake, a drip fence or wing fence installed inboard of the vent which is running in line of flight.Drip fence stop flow of leakage fuel towards engine and brake and this will prevent fire hazard condition.

Disadvantage of drip fence is drag penalty as the drip fence is in the free air.

Watch this blog video click below link

https://www.youtube.com/watch?v=IwWRirZZ5jM

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

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

Youtube Channel

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