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CXpilottobe
3rd May 2012, 11:47
Do the flaps affect the propeller-driven aircrafts in a same fashion as they affect the jets? :ugh:

And an additional questions is that could anyone help to clarify what is being defined when it says increasing the EFFECTIVE wing area during the used of flaps?
Which part of the wing is actually the EFFECTIVE part?:confused:

whiskey1
4th May 2012, 02:13
Flaps tend to be more effective on Propellor powered aircraft due to the slipstream (power on) from the prop increasing the airflow over the flapped area. This may be particularly noticable with one engine inoperative.

Fowler flaps (as fitted to most large transport aircraft and some small ones) deploy by moving down and backwards. They increase camber and wing area.

Other types of flaps (eg simple or split) just increase the camber with no change to the wing area.

CXpilottobe
4th May 2012, 03:13
Thank you whiskey.

So they are actually of the same fashion just that it tends to be more effective on the prop-driven aircrafts.

OK now I see the difference.
Can you also further clarify on the terminology of "effective wing area"? Does it actually mean the whole wing or just a certain part of the wing?

Million thanks.

fernytickles
4th May 2012, 08:13
Camber - Camber (aerodynamics) - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Camber_%28aerodynamics%29)

In aeronautics and aeronautical engineering, camber is the asymmetry between the top and the bottom surfaces of an aerofoil

Chamber - cham·ber (chmbr)
n.
1. A room in a house, especially a bedroom.
2. A room where a person of authority, rank, or importance receives visitors.
3. chambers A room in which a judge may consult privately with attorneys or hear cases not taken into court.
4. chambers Chiefly British A suite of rooms, especially one used by lawyers.
5. A hall for the meetings of a legislative or other assembly.
6. A legislative or judicial body.
7. A board or council.
8. A place where municipal or state funds are received and held; a treasury.
9.
a. An enclosed space or compartment: the chamber of a pump; a compression chamber.
b. An enclosed space in the body of an organism; a cavity: the four chambers of the heart.
10.
a. A compartment in a firearm, as in the breech of a rifle or the cylinder of a revolver, that holds the cartridge in readiness for firing.
b. An enclosed space in the bore of a gun that holds the charge.

And to answer the original question, yes flaps do affect jets in a similar fashion to propeller aircraft, increasing lift & drag.

Luke SkyToddler
5th May 2012, 08:14
"Effective wing area" means the whole wing, as viewed from on top of the aircraft looking down.

If the flap moves backwards and down, it increases the effective wing area.

If the flap just moves down, it doesn't.