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Welcome to the CPL Performance question and answer forum. Please feel free to post your questions but more importantly also suggest answers for your forum colleagues. Bob himself or one of the other tutors will get to your question as soon as we can.

- brentonrule
- Topic Author

Having now almost completed the CPL Performance book; and about to do all the tests again I'd like to offer some thoughts to other students on how I beleive you can make sure you pass this exam.

In short, study and learn every page and especially get your head around the 'concepts'__before__ you try and learn the formulas. This may sound like I am being a kindergarten teacher, but beleive me for those who have done this, the only way to get it accurate is to have a firm understanding of the 'concepts' of MTP, PNR, Moments, Arms, Weights, C of G, Ballast etc etc.

One thing that I kept getting caught on was using the wrong measures in the formulas when calculating W&B and C of G. Make sure that you don't use Moments when you should use millimeters and make sure you have a grasp of when to use 10,000 and when to use 1,000 on the C of G charts for the formulas.

For me, the best way was to do EVERY page slowly and carefully and as I did each question I'd then check the answer to see how I was progressing.

Hope this doesn't sound like I am patronising anyone; I just want to give confidence to those (who may be like me) who looked at this text and said 'OMG how will I ever get through this?' - I am making good progress and I beleive that I will pass this exam thanks to Bob's fantastic teaching methods and quality texts.

In short, study and learn every page and especially get your head around the 'concepts'

One thing that I kept getting caught on was using the wrong measures in the formulas when calculating W&B and C of G. Make sure that you don't use Moments when you should use millimeters and make sure you have a grasp of when to use 10,000 and when to use 1,000 on the C of G charts for the formulas.

For me, the best way was to do EVERY page slowly and carefully and as I did each question I'd then check the answer to see how I was progressing.

Hope this doesn't sound like I am patronising anyone; I just want to give confidence to those (who may be like me) who looked at this text and said 'OMG how will I ever get through this?' - I am making good progress and I beleive that I will pass this exam thanks to Bob's fantastic teaching methods and quality texts.

Last Edit: 10 years 1 month ago by brentonrule. Reason: accuracy

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- captainellzy

Good points Brenton, you're absolutely right. Honestly, you can't just waltz into this exam and expect to get it in one. Take it from me, I did it 3 times!

First time I was too blase about it and it's not a good idea considering the expense to say nothing of your confidence. I struggled to get it all done in time and ended up blindly choosing answers by the end of it to hopefully salvage some marks. Failed dismally. Second time my mark got worse. By the third time I left with over an hour to spare and got 3 questions wrong.

If you have ANY queries about ANY part of the book then ask here! Please please please do it.

Good luck

First time I was too blase about it and it's not a good idea considering the expense to say nothing of your confidence. I struggled to get it all done in time and ended up blindly choosing answers by the end of it to hopefully salvage some marks. Failed dismally. Second time my mark got worse. By the third time I left with over an hour to spare and got 3 questions wrong.

If you have ANY queries about ANY part of the book then ask here! Please please please do it.

Good luck

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- Andrewy

My advice (only did it last week) would be to read the question thoroughly and work out what you have to do and which data to use.

I found that they put more data than you need in the question, so don't waste time or get confused!

The good part about this exam is it isn't be too wordy (as some other exams are) so you don't have to struggle trying to work out what they're asking. It's the only exam in clear plain English!

I found that they put more data than you need in the question, so don't waste time or get confused!

The good part about this exam is it isn't be too wordy (as some other exams are) so you don't have to struggle trying to work out what they're asking. It's the only exam in clear plain English!

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- brentonrule
- Topic Author

Thanks guys. I am having some difficulty (as Andrew says) in defining which data and which methods to use to find things like 'how much fuel to add' and 'how much weight to remove' and 'what do you do when you add a passenger - how much weight to remove and from where?' ie: do I use the CoG charts or do I use the formula flow charts? Is there a simple way to decide quickly which method to use?

For example.

Q 6 page 5.54 - I began by doing a flow chart and used the Echo ZFW as the baseline. When I did this however I got an answer greater than the tanks would hold because the shift was too much. OK - stumped, now what? Looked at the answer on page 5.83 and it was a simple 'look at the charts and plot "A" and "B".

Q 7 uses the same logic but buggered if I could see why. When I first looked at it I again thought of the flow chart - wrong again - it was the simple CoG chart.

Q 8 Ah Ha he thinks - must be a CoG chart again - wrong - it is a formula flow chart with a simple 'how much weight'......

I will try them all again, but if there is a simple way to quickly identify what method to use, that would be a good start.

Thanks.....

For example.

Q 6 page 5.54 - I began by doing a flow chart and used the Echo ZFW as the baseline. When I did this however I got an answer greater than the tanks would hold because the shift was too much. OK - stumped, now what? Looked at the answer on page 5.83 and it was a simple 'look at the charts and plot "A" and "B".

Q 7 uses the same logic but buggered if I could see why. When I first looked at it I again thought of the flow chart - wrong again - it was the simple CoG chart.

Q 8 Ah Ha he thinks - must be a CoG chart again - wrong - it is a formula flow chart with a simple 'how much weight'......

I will try them all again, but if there is a simple way to quickly identify what method to use, that would be a good start.

Thanks.....

Last Edit: 10 years 1 month ago by brentonrule. Reason: spelling

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- bobtait
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- Posts: 2203
- Thank you received: 186

Brenton

The rules are as follows.

If the question asks you to**SHIFT** weight, you can **ALWAYS** use the flow chart and solve it with your calculator.

If the question is asking you to add or subtract weight, then you must consider which limit is likely to be the problem. You can usually see that if you plot roughly [even with your finger tip] where you are to start with. If it is going to be an**aft limit** problem, once again you can **ALWAYS** solve it with the flow chart.

The only time you will ever need to plot the two points on the envelope, is when you are*ADDING or SUBTRACTING weight to get to the FORWARD LIMIT.*

This is because the forward limit changes with weight, so you never know what the forward limit is until you know how much weight you are going to add. So in that case, you can't use your calculator - you have to use the envelope. However the aft limit never changes so you can use the flow chart for**any** aft limit problem whether shifting, adding or subtracting weight.

*So remember:*

Shifting weight for either forward or aft limit problems - always use the flow chart.

*Any* aft limit problem - always use the flow chart.

Adding or subtracting weight to get to the*forward* limit - use the envelope

The rules are as follows.

If the question asks you to

If the question is asking you to add or subtract weight, then you must consider which limit is likely to be the problem. You can usually see that if you plot roughly [even with your finger tip] where you are to start with. If it is going to be an

The only time you will ever need to plot the two points on the envelope, is when you are

This is because the forward limit changes with weight, so you never know what the forward limit is until you know how much weight you are going to add. So in that case, you can't use your calculator - you have to use the envelope. However the aft limit never changes so you can use the flow chart for

Shifting weight for either forward or aft limit problems - always use the flow chart.

Adding or subtracting weight to get to the

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- brentonrule
- Topic Author

Thanks Bob, this is exactly what I was trying to get my head around. I have done all the drills and all the exercises but distilling it into a simple set of rules was my dificulty. This is a great help.

By the way we are hoping to get away on our trip sometime in the next 7 days so whenever we get going I'll let you know and hopefully see you in Redcliffe.

Cheers for now.

By the way we are hoping to get away on our trip sometime in the next 7 days so whenever we get going I'll let you know and hopefully see you in Redcliffe.

Cheers for now.

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- Marko
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- Posts: 11
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Hi Bob just going back over some old posts to sort a problem I am having using flow chart or envelope Did you say to use the flow chart with any of the problems that required to be solved for aft c of g adding weight?n page 161 an envelope has been used to solve aft Addition of weight

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- bobtait
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- Posts: 2203
- Thank you received: 186

If the problem involves the **aft limit**, you can use the flow chart for **all operations** - adding, subtracting or shifting weight.

If the problem involves the**forward limit**, you can use the flow chart **only for shifting weight** (that means weight isn't changing)

If the problem involves the**forward limit** and you are **adding or subtracting weight,** then you should use the envelope (two-point method). If weight is changing on the forward limit you cannot use the flow chart.

If the problem involves the

If the problem involves the

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