Aerocourse ATPL

[y2kunals]

Hi, I've looked through the forums for some help, and came across a thread that had an answer to the question I was looking for (Section 5 #28-31)... the answer was as follows:

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For solving .... find HW or TW component on runway. find temp, follow to runway, and apply "wind correction", then "altimeter correction"

Example: Flap 15, Wind 100@9, QNH 29.98, Temp 30'C

Runway 15 & 33 avail. HW or TW is 7.5 Kts, Weight at 30'C for 15=31870, and for rwy 33=34200

so .... under notes =25lbs/kt HW if runway 15, and +55lns/kts if rwy 33
if TW then -140lbs/kt on 15, -60lbs/kt if 33

Rwy 15 : 31870+(7.5x25) = 31968
Rwy 33 : 34200-(7.5x60) = 33750 <--- Correct Answer
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My question is, how is Wind 100@9 = 7.5kt HWC or TWC on 15/33? Secondly, the updated chart in my book says to deduct 75 for each kt TWC on 33, but the answer above uses 60.

When I did the question, I got 6kt HWC/TWC on 15/33 and my answers are 31930/33750 respectively. That's answers a) and b)... the CORRECT (as per book) answer is b) - but why would I go with b)? You would assume that you should takeoff with a HWC wouldn't you? Why is the TWC answer correct?

I can't seem to get anything between #28-31 correct... any help would be GREATLY APPRECIATED... considering I am writing the exam tomorrow morning!

[Hawker]

#28
Temp = 24C
24degrees C gives you 33140 for Rwy 15
13kt HW (x25lbs/kt) give you an extra 325lbs
325 + 33140 = 33465lbs

Also check the updated Takeoff performance chart here
http://www.aerocourse.com/courses.php?id=8
"In the 4th edition of the ATPL workbook, the DASH 8 ATOG chart that affects computing the answers to questions 30 and 31 was inadvertently inserted as an older version. The new version of that chart is available here on the Web site."

I think the only difference is weights for the 26 and 28 degrees column for rwy 15

as for the other questions, I'll get back to you if I figure those out lol

Good luck!

[Hawker]

This is also off the aerocourse website if it helps

"As a hint for Q30, you have to look at both runway and airborne factors of the chart. For Q31, you have to look at the wind and altimeter corrections."

[y2kunals]

Hey, thanks a lot for your help. I sorta figured out #28. I mean the answer works out the way it's supposed to. I'm still stumped on 29-31 though! I have a feeling they might just be wrong, unless I'm the one who's seriously dumb!

If you don't mind, and you happen to know how they work, I don't get Section 6 #25-26. There's an answer to that question in the thread for the other questions, but that again doesn't make any sense whatsoever! I'm really losing my mind because of these Dash 8 charts... nothing seems to work out LOL

[Hawker]

#29
taking into account 6 kts HW for Rwy15 I get 31930
for Rwy 33 subtracting 450 for the tailwind gives me 33750
The question states to determine the maximum allowable take off weight.. therefor taking the tailwind (because you can up to 10kts so why not if the aircraft performs accordingly)
tailwind 33750lbs = maximum take off weight between the runways

[y2kunals]

hmm... if thats the case then don't you think for #28, the max weight should be 33,525lb on Runway 33 (TWC) ... they didn't even give that option!

[Hawker]

6-#25
I would use A 77.2%
That's the minimum torque you could use to get the 30550lb dash 8 off the runway
B is correct however it is not the minimum torque setting.

let me know if you need me to expand further on that one

[Hawker]

hmm... if thats the case then don't you think for #28, the max weight should be 33,525lb on Runway 33 (TWC) ... they didn't even give that option!

I would say that yes you are correct, however you are also correct in that they didn't give that option.. therefore it is not an option, therefore must be another correct answer.
gotta chose the most correct answer..
Don't worry once you get the exam done you don't have to deal with transports stupid exams anymore!

and fyi if it makes you feel better I didn't have any dash 8 take off performance charts on my exam... not to say that you won't get one one though!

[Hawker]

for 6-#26

I don't know if this is correct but this would be my reasoning.
33150lbs is your take off weight the closest for rwy 33 is 33160lbs which is a)83.3%.. however
if you look at the climb limit column for 33150lbs the closest is 33520lbs - torque setting 84.1%

thats how I rationalized it for my exam anyway!

[y2kunals]

I GET THEM NOW!! THANKS!!

Do you know how 5) 30-31 work?

[Hawker]

you're welcome!

as for #31
add 300 for HW on rwy15
subtract 400 for QNH 2992-2976 = 16
for every .02 subtract 50 so 400 (8 x 55)

27degrees - if you use the chart printed in the book (26 degrees = 32860) + (28 degrees = 32320) = 65180/2 (for 27 degrees) = 32590

32590 +300 - 400 = d) 32490

[Hawker]

And #30 again I'm not 100%
but if you look at the climb limit it's 33520 which is answer a)
33700lbs with no wind, and 34140 with the HW
however I'm guessing the climb limit of 33520 would be correct limiting answer (can't take off with 34140 and then climb out at 33520lbs!)

[Hawker]

Finished just in time for my flight!
PM me how it goes tomorrow if ya like, or if you get any of those charts on the exam
gotta jet
good luck!

[y2kunals]

Haha nice thanks a lot for your help! I'll PM you tomorrow for sure! Have a good flight!