Gidday Megzy

Welcome to the forums. The best thing you can do is go through the book carefully and try to find the references in the appropriate document. Although you will find that the questions in the book are a good indication of what you can expect in the CASA exam, there is no substitute for getting to know the documents. If you have done all of the tests and exercises in the book, and the online cyber exams that should help. If you have any questions as you progress, make sure you post them to this forum. We will always do our best to help where ever we can.

Good luck.

Thanks Bob, Cant believe i didnt use this site with all my other exams.

Question.
How do you work out the lowest flight available when they give you a QNH of 985.
I know you look at the transition level page in the AIP, and i thought you just read the flight level thats next to the QNH, but didnt work this time.

Megzy

You will notice the figure on page 5 of ENR 1.7 says that FL110 is not availale when the QNH is below 1013 and FL115 is not available if the QNH is below 997. Since 985 is less than 997, you cannot have either FL110 or FL 115. The lowest flight level available for cruising on that day would be FL120. However you would also have to consider the direction of flight and the category of flight. FL120 would only be available for IFR flights with a flight planned track between 180 and 359. For a VFR flight with a flight planned track between 000 and 179, you would have to plan at odds + 500. So the lowest level available for a VFR flight in those directions would be FL135. A VFR flight with a flight planned track between 179 and 000 would be able to plan at FL125

Does the question give you a direction? If not, the answer would be FL120, since it would be the lowest flight level available.

Cheers

Thanks Bob,

That makes more sense now.
YAY

Hi Bob,
what if the QNH is 997HPA? Is FL115 still available for this value?
thank you in advance

[quote="bobtait" post=1756]Megzy

You will notice the figure on page 5 of ENR 1.7 says that FL110 is not availale when the QNH is below 1013 and FL115 is not available if the QNH is below 997. Since 985 is less than 997, you cannot have either FL110 or FL 115. The lowest flight level available for cruising on that day would be FL120. However you would also have to consider the direction of flight and the category of flight. FL120 would only be available for IFR flights with a flight planned track between 180 and 359. For a VFR flight with a flight planned track between 000 and 179, you would have to plan at odds + 500. So the lowest level available for a VFR flight in those directions would be FL135. A VFR flight with a flight planned track between 179 and 000 would be able to plan at FL125

Does the question give you a direction? If not, the answer would be FL120, since it would be the lowest flight level available.

Cheers

AIP ENR 1.7 page 5. If the QNH is 997, FL 115 would still be available. The QNH has to be LESS THAT 997 for FL 115 to be unavailable.

Bob