Cathay interview debrief part II
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If you don't know that one off the top, you're not digging deep enough. that's a basic ops question, and this should be an indicator that you need to spend more time in the books listed above. I would also recommend the search function on this site, as well as Google search.
Good luck!
Good luck!
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Canadian Beech,
It's the opposite actually, I digged too much. There's a question in XYZ book about larger flap setting and the answer was longer runway is needed and then the other books that I've been reading is saying the opposite.
I'm just getting confuse, I understand that this question can get tricky, larger flap setting will get you airborne sooner but will degrade your climb gradient.
FYI, I hit the books 7 to 9 hours a day for a month now.
Thanks for the advice though.
It's the opposite actually, I digged too much. There's a question in XYZ book about larger flap setting and the answer was longer runway is needed and then the other books that I've been reading is saying the opposite.
I'm just getting confuse, I understand that this question can get tricky, larger flap setting will get you airborne sooner but will degrade your climb gradient.
FYI, I hit the books 7 to 9 hours a day for a month now.
Thanks for the advice though.
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Hi Medwin,
I think that the question you are thinking of is: which runway would provide better 2nd segment climb performance, 8000ft or 10000ft?
This is not a flap question but a climb "profile" consideration.
There is no doubt that increased flap settings is good for TORA and bad for WAT/Climb. As usual, everything is a compromise. Thank goodness for computer generated performance numbers and astute dispatchers.
VRT
I think that the question you are thinking of is: which runway would provide better 2nd segment climb performance, 8000ft or 10000ft?
This is not a flap question but a climb "profile" consideration.
There is no doubt that increased flap settings is good for TORA and bad for WAT/Climb. As usual, everything is a compromise. Thank goodness for computer generated performance numbers and astute dispatchers.
VRT
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VRThomas,
Here's the actual question.
page C-4 queation number 22.
A take off with more than normal take off flap setting will result in.
a. longer take off distance
b. shorter take off distance
c. the same take off distance
correct answer is a.
Forgive my stupidity but am I missing something? I know from experience that if we use larger flap setting the take off roll will be shorter and the books that I'm currently reading are saying the same thing.
Here's the actual question.
page C-4 queation number 22.
A take off with more than normal take off flap setting will result in.
a. longer take off distance
b. shorter take off distance
c. the same take off distance
correct answer is a.
Forgive my stupidity but am I missing something? I know from experience that if we use larger flap setting the take off roll will be shorter and the books that I'm currently reading are saying the same thing.
. Sorry!
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I think that the confusion may be arising from a definition of TO "distance".
Is Take-Off Distance Take-Off Roll? Or is it the distance required to acheive a certain height to clear an obstacle and/or achieve a height of 400ft AGL?
In the book "Aircraft Performance Theory for Pilots", (P.J. Swatton), they define take-off distance as:
"The distance from brake release point to the point at which screen height is attained."
Does this change our answer? Is the question -in- question, refering to a different definition?
I tend to think that anywhere a climb of any amount is required the ground distance to a particular height will increase with flaps. But then again, does the decrease in ground roll compensate for the slower rate of climb to the defined screen height and therefore produce the same net climb ratio from point of brake release?
VRT
Is Take-Off Distance Take-Off Roll? Or is it the distance required to acheive a certain height to clear an obstacle and/or achieve a height of 400ft AGL?
In the book "Aircraft Performance Theory for Pilots", (P.J. Swatton), they define take-off distance as:
"The distance from brake release point to the point at which screen height is attained."
Does this change our answer? Is the question -in- question, refering to a different definition?
I tend to think that anywhere a climb of any amount is required the ground distance to a particular height will increase with flaps. But then again, does the decrease in ground roll compensate for the slower rate of climb to the defined screen height and therefore produce the same net climb ratio from point of brake release?
VRT
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A take off with more than normal take off flap setting will result in.
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As VR-HDB mentioned I believe (beyond normal) is the key phrase. Normal, i am assuming is any of the approved take-off flap settings for a particular aircraft. Most normal or approved take-off flap settings provide the most lift for the least ammount of drag. As in a fowler flap the flap moves aft increasing wing area thus lift during inital flap or take-off selection. As the fowler flap is moved to a selection beyond take-off, drag is increased considerably due to the more downward movement of the flap. Hence if a flap selection beyond normal were used this would result in more drag thus slower acceleration thus more runway used for a given non-normal flap setting.
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Medwin,
I think I see where your confusion is coming from.
In your response to Canadian Beech you said that the correct anwer was: "longer runway is required".
"Longer runway" was not one of the options.
Using the definition of take-off distance that I cited previously, the consideration includes the distance required to achieve a screen height (usually) of 35 feet. Some of the "distance" required can be beyond the end of the runway!
If you were departing off a runway that was limiting because of field length with a lower flap setting , you may think about using a higher flap setting to "get off" a little quicker. But, because you are required to be able to climb to a prescribed screen height within a certain distance you may jeopordize that by lowering you climb gradient. In other words, you have shortened your take-off roll but increased your take-off distance.
So you were thinking =runway length= required but the question was relating to =take-off distance= required.
OK, now my head hurts!
G'night
I think I see where your confusion is coming from.
In your response to Canadian Beech you said that the correct anwer was: "longer runway is required".
"Longer runway" was not one of the options.
Using the definition of take-off distance that I cited previously, the consideration includes the distance required to achieve a screen height (usually) of 35 feet. Some of the "distance" required can be beyond the end of the runway!
If you were departing off a runway that was limiting because of field length with a lower flap setting , you may think about using a higher flap setting to "get off" a little quicker. But, because you are required to be able to climb to a prescribed screen height within a certain distance you may jeopordize that by lowering you climb gradient. In other words, you have shortened your take-off roll but increased your take-off distance.
So you were thinking =runway length= required but the question was relating to =take-off distance= required.
OK, now my head hurts!G'night
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flaps and take off run
Increase in flap setting vs takeoff run.
Fowler type flaps, within the takeoff range will increase lift more than drag and thus increase the take off run. However, if you keep increasing the flap setting out of the takeoff range than the drag will increase greater than the lift and reduce the takeoff range.
A better way to think of it is: Take off ground run increases with flap setting within the take off range, dereases outside of this range.
Cheers.
Fowler type flaps, within the takeoff range will increase lift more than drag and thus increase the take off run. However, if you keep increasing the flap setting out of the takeoff range than the drag will increase greater than the lift and reduce the takeoff range.
A better way to think of it is: Take off ground run increases with flap setting within the take off range, dereases outside of this range.
Cheers.
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Hi Medwin,
A takeoff with more than normal takeoff flap setting will result in:
a. longer takeoff distance.
b. shorter takeoff distance.
c the same takeoff distance.
I too believe 'b' is the answer, the increased takeoff flap setting will (as most of the books say) decrease the takeoff roll but degrade the climb ability. I would imagine the questions are supposed to be relatively direct. I think the answer code in the back is just wrong (look at the ACE book,quite a few errors).
Cheers PJ_Slick
A takeoff with more than normal takeoff flap setting will result in:
a. longer takeoff distance.
b. shorter takeoff distance.
c the same takeoff distance.
I too believe 'b' is the answer, the increased takeoff flap setting will (as most of the books say) decrease the takeoff roll but degrade the climb ability. I would imagine the questions are supposed to be relatively direct. I think the answer code in the back is just wrong (look at the ACE book,quite a few errors).
Cheers PJ_Slick
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Hey guys,
Just wanna place my point of view here on this flap question as well. If I have to answer this question, I'd choose "a"
longer distance. This is just wat i reckon it is. As far as I know, when I receive my trainning in a Cessna 152 (which has the fowler type flaps), when taking off using minimum runway, I put down the take-off flap, so yea.....i think using more than T/O flap would actually increase the take-off distance. Any thoughts from others?
Ken
Just wanna place my point of view here on this flap question as well. If I have to answer this question, I'd choose "a"
longer distance. This is just wat i reckon it is. As far as I know, when I receive my trainning in a Cessna 152 (which has the fowler type flaps), when taking off using minimum runway, I put down the take-off flap, so yea.....i think using more than T/O flap would actually increase the take-off distance. Any thoughts from others?
Ken
