Boeing flap angle vs flap setting
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Boeing flap angle vs flap setting
Hi guys,
looked it up on the internet but no outcome.. so here I am:
I know that boeing flap settings (UP - 1 - 5 - 10 - 15 -30 -40)
are not expressed in degrees but they are just...well.... just numbers!
so does any of you have a technical explaination + his/her (I am an equal opportunities poster
) source of information?
thanks in advance!
looked it up on the internet but no outcome.. so here I am:
I know that boeing flap settings (UP - 1 - 5 - 10 - 15 -30 -40)
are not expressed in degrees but they are just...well.... just numbers!
so does any of you have a technical explaination + his/her (I am an equal opportunities poster
) source of information?thanks in advance!
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Maybe because Flap 5 in a 737 is could actually be Flap 4.57 degrees of extension and thus it is simpler to use units of flap rather than too many fractions of degrees? Just guessing.
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Maybe because Flap 5 in a 737 is could actually be Flap 4.57 degrees of extension and thus it is simpler to use units of flap rather than too many fractions of degrees? Just guessing.
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It really doesn't matter if you specify flaps in degrees (0, 5, 10, 15, 30, 45) of flaps by numbers (1, 2, 3, 4) at some point they had to be verified as meeting a specific degree at each point (plus or minus a specific amount).
However, IMO using using flaps 1, 2, 3, 4 is just another example of removing the pilot from have and input into flying the airplane. ie they don't need to know the exact flap position just a number?
However, IMO using using flaps 1, 2, 3, 4 is just another example of removing the pilot from have and input into flying the airplane. ie they don't need to know the exact flap position just a number?
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For Boeing 777 and 787:
Flaps 0: Both leading edge slats and training edge flaps full retracted
Flaps 1: Leading edge slats extended, but trailing edge fully retracted
Flaps 5-20: Takeoff flap settings - Leading edge slats extended with increasing amount of trailing edge flap with increasing handle position.
Flaps 25 and 30: Landing flap settings - Leading edge slats further extended to the gapped position with increasing amounts of trailing edge flap with increasing handle position.
Note that Flap 20 is used for landings when control system is in either the Secondary or Direct reversionary modes.
Flap and slat angles as measured with a protractor on the surface do not match the handle setting numbers, but commonality is kept with regard to the uses of each handle position.
Flaps 0: Both leading edge slats and training edge flaps full retracted
Flaps 1: Leading edge slats extended, but trailing edge fully retracted
Flaps 5-20: Takeoff flap settings - Leading edge slats extended with increasing amount of trailing edge flap with increasing handle position.
Flaps 25 and 30: Landing flap settings - Leading edge slats further extended to the gapped position with increasing amounts of trailing edge flap with increasing handle position.
Note that Flap 20 is used for landings when control system is in either the Secondary or Direct reversionary modes.
Flap and slat angles as measured with a protractor on the surface do not match the handle setting numbers, but commonality is kept with regard to the uses of each handle position.
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Originally Posted by XPMorten
flap 5 in a 733 is 12,5 deg.
it's amazing how everybody is flying without knowing the degrees he is actually using... ok, not very useful but still...
Originally Posted by Exaviator
Angle of flap in relation to the chord line of the wing expressed to the nearest degree.
really interested to find an answer!
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Originally Posted by colorblind...
it's amazing how everybody is flying without knowing the degrees he is actually using
1)You know when to use a particular 'setting'
2)You know how to use it
We could call it 1 banana, 2 banana etc and it would make not a scrap of difference.
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In the Boeing MX manuals you will find the Flap Setting vs Actual degrees in the Flt Controls section. For the 744 there is a range of acceptable values per flap setting. These values roughly correlate to the Flap setting selected i.e. 5, 10, etc. I am not sure about other Boeing types but I would imagine they are very similar.
TRey
B744
TRey
B744
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Originally Posted by TRey
In the Boeing MX manuals you will find the Flap Setting vs Actual degrees in the Flt Controls section.
Originally Posted by BOAC
- I see from your profile that you have no actual involvement in aviation, so you need to know that to pilots it does not matter what the angle is as long as:-
1)You know when to use a particular 'setting'
2)You know how to use it
1)You know when to use a particular 'setting'
2)You know how to use it
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sharing some figures from the Mx manual, even if they are not describing what happens at every setting change...
H. The angle of flap extension is measured relative to the wing chord plane.
When the flaps are fully retracted, the trailing edge of the aftflap is
aligned with the wing chord plane. When the flaps are extended to 40
units, the angle between the wing chord plane and the midflap is
approximately 43 degrees. Since the aftflap moves relative to the
midflap, the aftflap rotates to an angle of approximately 69 degrees from
the wing chord plane.
When the flaps are fully retracted, the trailing edge of the aftflap is
aligned with the wing chord plane. When the flaps are extended to 40
units, the angle between the wing chord plane and the midflap is
approximately 43 degrees. Since the aftflap moves relative to the
midflap, the aftflap rotates to an angle of approximately 69 degrees from
the wing chord plane.
when the trailing edge flaps extend to the
0- to 1-unit position, pressurized fluid is ported through one of the
cylinder ports to fully extend the leading edge flaps and slats 2, 3, 4,
and 5. Slats 1 and 6 extend to the intermediate position. Moving the
trailing edge flaps to the 30-unit position ports pressurized fluid
through both cylinder ports. With the control valve in this position,
leading edge slats 1 and 6 fully extend.
0- to 1-unit position, pressurized fluid is ported through one of the
cylinder ports to fully extend the leading edge flaps and slats 2, 3, 4,
and 5. Slats 1 and 6 extend to the intermediate position. Moving the
trailing edge flaps to the 30-unit position ports pressurized fluid
through both cylinder ports. With the control valve in this position,
leading edge slats 1 and 6 fully extend.
Last edited by colorblind...; 24th Sep 2010 at 21:39.
