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Passed Performance!

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jkatz098 created the topic: Passed Performance!

HUGE thank you to everyone on the forum and the bob tait team, couldn't have done it without you

Failed the first time round with 62%
Passed today with 90% so I'm pretty happy

Very similar rundown in terms of marks that everyone else has posted, they divide the 2 mark sections into two for some reason.
7-10 1 marks
5-6 2 marks
another 5-8 1 marks
another 5-6 2 marks
3-4 3 marks
1 4 mark


Start with 4 marker, it's PNR, gave lots of details, specified very clearly what info from CAAP you would need (Fixed, variable)
Gives holding and cruise flows (mine has 108lph for all operations)
It was a straight forward question just asking what the distance to the PNR is
MAKE SURE YOU KNOW HOW TO WORK OUT ETAS, I cant stress this enough, had about 3 questions where it was needed, so know how to do it on your whizzwheel.

3 markers were all pretty simple, one on how many 20kg packages could you put in the rear compartment echo, another was about fwd limit in echo (I hate these ones) but they make it easy by limiting how much you could put in (eg MZFW, Rear Compartment max) and then the weight they want you to add is in 10kg bars, so you can just at eg 100kg and go down in 10kg to work it out.
A few on charlie, again super basic, just asking what the max cargo or pax could be all rear limit, make sure you don't go over the MTOW.

2 markers were a mix of minimum fuel needed, safe endurance calc, eti for a flight and P-charts. Make sure you read it all clearly and know when to have variable and fixed reserves. Some were fill in some were multi, p-charts I only got 1 fill in (Which I think I got wrong, no idea what CASA want for those, everyone seems to get at least one wrong and it's usually the fill in)
P-charts - I got 1 Cessna take-off and 1 Cessna landing, 1 piper takeoff, 1 echo landing. They either asked max weight or TODR, make sure you know when you can use the ambient or forecast winds or if they say "given the following"

1 markers were all pretty much theory based, a few cg to MAC%, 1 density height calc, question asking what BEW actually accounts for, a CP question which you need to read before you just jump straight in, "what happens to time with a cp if a tailwind is present vs nil wind." Time stays the same distance will change. I got the question on working out how much you have for TODA that I've seen a few people talk about on here. "TORA 1300m, ASDA 1400m, Clearway 80m beyond the ASDA, what's your TODA" just read to make sure where the clearway starts, sometimes the ASDA can be incorporated into the clearway, so it will either say it starts at the end of the runway or beyond the ASDA, it also gave displaced threshold but that is to trick you. A basic question on TOSS, when you can fly above VNO, max distance between runway strip markers (in the caap, it's just on one of the diagrams) a flight notification question asking what you put in section 18 DOF, it's in the aip super easy.

I finished with about 45 minutes to spare and the first time I sat it I just submitted and failed. This time I used the 45 mins to check over every calculation. On my working out I labelled each question so I could easily find it. I ended up finding a few errors with my P-charts (used the wrong surface) so make sure you just use all the time you're given and think about the 1 markers once you've gone over the calculation questions
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bobtait replied the topic: Passed Performance!

Well done. Congratulations on a great mark. Thanks for your very thorough debrief as well. Great effort- you should be proud of that!!

Bob
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jkatz098 replied the topic: Passed Performance!

Passed performance and got a reply from the big man himself!

Today is definitely my day!

Thanks Bob!
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MissSoph replied the topic: Passed Performance!

Congratulations ... it’s not easy... can you please just clarify for me the ETAS?
Are you meaning that with a particular density height and CAS you work out the TAS on the whizz wheel?
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jkatz098 replied the topic: Passed Performance!

MissSoph wrote: Congratulations ... it’s not easy... can you please just clarify for me the ETAS?
Are you meaning that with a particular density height and CAS you work out the TAS on the whizz wheel?


So when you work out the crosswind and head/tailwind components. On your whizzwheel if the crosswind component is more than 10 degrees then you need to go to the arrow you set your TAS on and you’ll see the etas section, see which speed the degrees lines up with and that’s your new tas/etas
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John.Heddles replied the topic: Passed Performance!

Reading between the lines, MissSoph uses a Dalton nav computer, not a Jepp machine ?

If that is the case, then ETAS would have no functional meaning for her as it plays no part in the full nav triangle's solution.

On another tack, with the Jepp solution, ETAS determination is a fundamental part of the secondary triangle's nav solution.

While the error involved in omitting its calculation reduces as the drift angle reduces, the usual practice of using 10 degrees as a trigger can be a tad suspect at times.

My recommendation is to run the ETAS calculation all the time (after all, that is the correct solution) as that makes the sequence simpler, while noting that, as the drift angle reduces below 5 degrees, ETAS is very nearly the same as TAS.

This point tends to confuse many students - if needs be, we are only too happy to explain in more detail.

As an aside, the examiner carries the ETAS calculation down to 5 degrees.

Engineering specialist in aircraft performance and weight control.
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BStanmore replied the topic: Passed Performance!

Just confirming you used the graphical solution for the forward limit echo problem? or did you trial and error in 10 kg increments?

Also did you graph the Charlie read limit problems or used bob's "echo" loading flow chart... I have found it works for a Charlie rear limit problem as its a fixed rear limit... Anything on this Bob?

Is there definition for BEW anywhere??

And also could you give a specific example about your TODA question?
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John.Heddles replied the topic: Passed Performance!

Empty weight definition.

This is defined in CAO100. 7 and no-where else. All other terms, essentially, are not defined other than within the context of their use. Basic empty weight can mean whatever you want it to mean so it always should be defined within the context of its use.

The exam problem is that the examiner uses a mix of old data (which used the old 100.7 empty weight definition) and newer data (which uses the current definition).

Unfortunately, as small aircraft rarely are reweighed, we still see lots of old definition data out there in the Industry.

The difference is the oil load. In earlier days, we had lots of big radials, for which oil was a very definite consumable and not included in the empty weight. Once these really started dying off, it was far more appropriate to include oil in the empty weight (think HO engines). I was one of several WCOs who stirred the pot long ago... which led the Regulator to change the CAO definition.

Engineering specialist in aircraft performance and weight control.
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jkatz098 replied the topic: Passed Performance!

I did it in 10kg trial and error. Rear has a max limit so I just went backwards from that. I graphed it as well just so see, but ended up going down in 10s

Yeh because of the fixed rear you can use the same formula as the echo one.

I didn’t get a bew definition question, but if my memory is right, in the casa booklet ones of the loading has a definition of BEW if you get stuck

What I wrote about was the actual question on TODA. It just wanted to know what the toda would be given those values.
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John.Heddles replied the topic: Passed Performance!

Once again, be wary of terms in weight and balance. Industry practice, over the years, has resulted in its being a bit of a dog's breakfast.

For BEW, seeing that is being discussed, you will find various "definitions" around the Industry fleet.

A very common practice before the empty weight definition was amended to include full oil saw most of us define empty weight as per the then Order (undrainable oil), but then define some other term (often BEW) including full oil for operator convenience. However, I could dig aircraft out from my files showing quite some variety in configuration detail ascribed to BEW.

The poor examiner is stuck with the history and reality and is trying to make sure that folks finish the exams with an idea of the mess which is weight control out there in the Industry.

Re TODA, the only sensible answer for your example is 1480 feet. Beware, though, that the amount of clearway is restricted by airport design standards, although this is unlikely to crop up in the exam questions. In the real world the limit will be incorporated into the declared distances.

On a point of definition, clearway starts at the end of TORA. (refer MOS 139). If the exam question appears to say otherwise, that is just the examiner challenging your understanding a tad.

Engineering specialist in aircraft performance and weight control.
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