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Aviatordan created the topic: Exam Review
I passed performance last friday so I thought I'd take some time to give those who've yet to have the pleasure of sitting their exam a little insight into what you could possibly expect.
Let me start off by saying that this exam is definately the sort that requires a well-rested and focused mind. It's not hard, if you've done the study and you know you're stuff, you'll be fine; the reason for the stress is that it can be a bit time limited. 2.5 hours seems like plenty of time but some of the questions (some weighted up to 3 marks each) can take a fair chunk of time to complete. This is especially true if you're like me and like to double check that you have transferred everything from the question into the load sheet correctly and that you haven't put down "400" instead of "600" or some silly mistake like that. At any rate here's a break down of my exam:
The exam consisted of 33 questions, ranging from 1 to 3 markers. The 1 markers were all common sense based questions such as the effect of increased surface air temperature on the TODR. There were a couple asking for the definitions of "empty weight" and "LDA".
The 2 markers consisted of PNR and ETP related questions (I think there were 4 in total, 2 on ETP and 2 on PNR).
There were also questions relating to the calculation of the flight fuel required for a charter flight. Make sure you don't forget the variable reserve!!! I found in these questions they only specified that you need a fixed reserve, however they called it a charter flight and therefore you were just supposed to know that as a charter flight you need to carry the extra 15% flight fuel, tricky buggers.
Also included were a couple of weight to shift and weight to add questions in the echo. I only got rear limit questions, which is annoying as I was really looking forward to using the forward limit formula. One asked "what is the MINIMUM ballast fuel that must be used" i.e. you had to use as much hard ballast as possible before using fuel as ballast. Pretty much straight out of the text book.
There were also a couple of simple take-off and landing performance questions using take-off and landing chart type 1, the linear take-off and landing charts and the Echo take-off and landing charts.
There were two as I recall asking you to convert CG positions as mm aft of the datum into % MAC and 2 questions on floor loading intensity.
Moving on to the more labor intensive questions, there were 3 or 4 questions using the Aplha loading system. They were all asking "with the current load how much baggage or fuel can be added whilst maintaining balance throughout the flight".
I didn't get any on loading system Bravo however there were 3 or 4 on loading system Charlie and 3 or 4 on loading system Echo.
All in all the exam was nothing that wasn't expected. I guess my biggest suprise was how many questions there were asking about the loading systems other than the Echo. I guess I had it in my mind that the echo would be the predominating figure. However, that was not too big of a problem, as long as you don't put all your time and effort in to the Echo and study up on the other's you'll be fine!
Good luck to you all, let me know how you went. =]
Well done Dan. Congratulations. A very good summary and certainly supports my experience with this one. This was the subject I found the hardest of all but having read your summary I agree there is no substitute for 'knowing your stuff'. And yes the time limit is a killer.
The only other thing I'd say to other students is to have a look at ALL of the posts on the subjects in these forums as many of your questions will have already been asked by others and answered by Bob and Richard.
I just did my test today and thought it was quite a fair test - aslong you have worked through the questions in the book, the exam should be no surprise.
The only annoying thing is trying to work out answers on the loading and takeoff/landing graphs. You have to be very accurate with your lines because some of the answers could go either way.I especially hate the ones where you are told to find the max weight that can be added, and the line you draw crosses the envelope in a less than distinct way. A few mm can make so much difference!
I got 1 question each on the alpha, bravo and charlie load systems, the rest were echo.
About 2-3 on PNR and ETP's, but if you can do the exercises in the book, you will nail these.
The high mark questions were geared towards the loading problems of CG, and how to add/shift weight to make it right. Again, if you can do the exercises in Bob's book, then these should be reasonable. It really is a matter of rechecking your answers and workings to make sure you haven't missed anything. These take the bulk of the time, so if you know the process for solving these problems, you should have ample time to finish the exam.
I sat Performance exam 2 weeks ago wasn't feeling ready but ran out of time to shift it so I sat it ending up getting 58% I struggled in weight balance questions regarding Echo.
Can someone please help in regards to adding minimum fuel ballast?
I had 3 questions on this topic, I'm not sure if I got them wrong but just checking I'm doing it right.
I added as much hard ballast as possible in each compartment that had space checking I didn't exceed the ZFW and each compartment's max weight. I was still in balance so I answered no fuel ballast required. All 3 questions had the same outcome but surely it couldn't be the same answer I must have done something wrong???
Is there only one compartment you can add hard ballast too in regards to wether its aft the limit or forward the limit?
It's my last exam for my CPL so feeling a little nervous for the 2nd re-sit.
Don't worry about the exam, at least you know what to expect now!
As for the loading problem in the echo, I think I can help you out with this one.
As far as I can tell from the description of your method, you were doing it right. I am pretty certain they will only ask questions relating to minimum fuel ballast required when the question if referring to an aft limit problem. There may be a question saying "An echo is loaded outside the forward limit, how much fuel ballast must be carried to place the echo within the CG limits" but I don't think they can split hard and fuel ballast as you need to use the graphical method for adding/subtracting weight in a forward limit problem. This means that, since it will always be an aft limit problem, you should always start off by adding as much weight as you can to the nose compartment, which will have the greatest effect on moving the CG further forward.
As you said, you always need to check that you're not encroaching on the max ZFW, the max compartment weight and the max floor loading intensity, the latter I don't think they try and trick you on unless the question is specifically about floor loading intensity but is a consideration in practice.
The way to go about these questions is to:
1 - Determine your current CG position.
2 - Add as much weight as you can to the compartment that will have the greatest effect, which in this case is the nose compartment.
3 - Check you new CG. If it is within limits, you're fine and don't need to add any fuel ballast.
4 - If the CG limit is still out, do a simple 'weight to add' flow chart to determine how much fuel ballast is required to move the CG back to its rightful place.
Good luck when you take the test again, mate! I hope this helps =].
Generally you'll find that after adding as much weight as you can into the nose compartment, you'd be getting very close to (if not touching) the max ZFW limit so there wouldn't be any room to add more weight into other compartments.
I think you'd also find (and this is purely my own syllogism) that with an aft limit problem asking to find minimum fuel ballast, adding weight to any compartment other than the nose locker would be detrimental. Since the nose is at 500mm aft and the tanks are at 1780mm aft, adding anything to a station further rear of these stations would act to oppose the desired forward movement of the CG.
So in answer to your question, I think adding weight to the most effective compartment is the only option.