Hi Guys
I'm just wondering if you can give a detailed explanation of this cyberexam question because my answer is wrong.
you are planing a take off at Cooma Snowy Mountains?
Ambient conditions
Local QNH 1033
Wind 140M 5Kts
Ambient temperature 0deg C
rwy 18/36 closed
maximum take off weight permitted by the Echo.

The TODA from my current ERSA is 682 and Slope 1.3% down to NW

Hi Johann,

Sorry, I don't have CASA Day VFR booklet to hand just at the moment so I can't work the problem with the chart on page 22.

Before we simply give you a worked answer anyway, just a couple of quick points that might help you pinpoint a problem:

Did you work with the Pressure Height and temperature at Cooma or just the Elevation and temperature? You'll need to use the Pressure height when you go into the chart.

Did you check the MTOW for an "uphill with headwind" as well as the "downhill with tailwind" takeoff? Sometimes it is better to accept a slight tailwind in order to cash in on a downslope.

What surface did you use? Since we can't use 18/36, we must use 14/32. This is an unsealed (gravel) runway (see the cross hatched appearance in the AD sketch in the Cooma entry in ERSA). Read Point 4.1 on page 14 of the CPL-PERF supplement:

Did you use the Performance charts in the CPL-PERF textbook supplement or the one in CASA's VFR (Day) Book? Try using the P-Chart in the CPL-PERF supplement instead and see if it gets you closer to the correct answer.

Let me know how you get on. If you still have trouble, we'll take a closer look at it.

Cheers,

Rich

P.S. check your PM - I have sent you the correct answer that is registered for this question.

Johann, we've taken another look at this question in the cyber exams and corrected it. 2620g was not right. The correct answer is lower than that - closer to the result you had chosen.

Thanks for the heads up on that one

Cheers,

Rich

Thanks a lot Richard for take the time to clarify my question. I really appreciate that. I was thinking too much stuff was driving me crazy.