Author Topic: Cowl-flaps  (Read 4999 times)

Offline EHM-1953 Daniel

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Cowl-flaps
« on: August 23, 2007, 04:52:04 pm »
hi guys, in advance of the orientexpress event i'd like to know what the Cowl flaps do, and when to use them..

i've seen them in many propeller aircrafts, but i really don't know when or how to use them..

thanx in advance :D

regards,
Daniel Sahlin EHM-1953 ESSA

Offline EHM-0654 Murray

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Cowl-flaps
« Reply #1 on: August 23, 2007, 05:07:27 pm »
Daniel,

I think I'm right in saying they're used as a cooling mechanism on piston engined aircraft... you open then prior to engine start (unless it's real cold OAT) and close them during the climb to stop the engine getting too cold (or vice versa ;))

I'll have a dig around in my many SEP checklists once I get home and give your a reasonable "definitive" usage.

EDIT: Wikipedia ftw!

Quote
Cowl

If the aircraft is equipped with adjustable Cowl Flaps:

    * Cowl Flap Position Control - Cowl Flaps are opened during high power/low airspeed operations like takeoff to maximize the volume of cooling airflow over the engine's cooling fins.
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Offline EHM-1001 Robert

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Cowl-flaps
« Reply #2 on: August 25, 2007, 12:18:18 pm »
Shortly, but correctly ;D

http://www.maam.org/airshow/images/r4d_exterior_6.jpg

These small flaps makes a bypass around the engine. On the ground (low speed) the flaps are open and let the air cool and flow around the engine, while in the air (high speed) the flaps are closed because the cool air that hits the engine face is just enough for cooling.

There is a sequence for open/close these flaps, because opening these flaps makes a bit more grip so you can use those for slow down on approach as well. And because of that, it is also important to close them immediately after takeoff.

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Offline EHM-1953 Daniel

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Cowl-flaps
« Reply #3 on: August 26, 2007, 12:55:42 pm »
ah okey, thanx alot guys :D makes sense ;D
Daniel Sahlin EHM-1953 ESSA