Hi there,

Struggling to get my head around the FIXED RESERVE of 90lts used in the example on page 4.49. I made the assumption of 15gallons which converts to 56.9lts...

I've probably missed something very very simple here. Your help would be greatly appreciated ahead of my exam on Friday!

Thanks
Daniel

Hi Daniel,

This is one of those situations where you need to read the question extra carefully. You have assumed the fixed reserve will be 15 gallons which is 45 minutes at 45% MCP in an Echo aircraft.

In this case however, the question explicitly states the fixed reserve is "45 minutes at cruise rate". The cruise rate is supplied as a "normal fuel flow" of 120l/hr. So, 45 minutes at 120l/hr = 90 litres.

Watch out for this since there's no reason why CASA can't drop one in like that as well. Ah, it's all good fun eh

Cheers,

Rich

Hi Richard,

Thank you!! lights are on!

I'm glad that question came up. For anyone studying Performance, you should be aware that not every question in the CASA exam will be based on flying the famous Echo aeroplane. Some students spend so much time on Echo problems that they get a bit of a shock when a question comes up that is based on the use of another aeroplane.

If the examiner writes a question on an aeroplane other than an Echo, he will have to give you all of the reserves and allowances in the question. Be prepared for questions that relate to aeroplanes other than the Echo. This applies to most of the questions on PNRs and ETPs. They are usually based on the use of an aeroplane other than an Echo.

In your example the aeroplane being referred to is obviously not a Echo.

Keep having fun...

Bob

Thanks Bob. What it actually prompted me to do was get my hands on the CAAP234-1(1). I soon realised that the 15gallons was derived from the 45mins @45% MCP not just a standard 15gallons all the time!!! Now I know the fixed reserve is 45mins at the specified fuel flow rate from the question.

Richard, thanks again!

Hi Team,

I got a decent result in my Performance exam! I found some previous tips from another students very helpful in preparing so thought I'd leave a few tips of my own.

The exam was actually a little more straight foward than I expected. With that said however I think the depth of preparation that I went to actually made it feel this way. So put the study in and you will be fine.

How I prepared:
1. Go through the brilliant B.Tait Performance text slowly answering ever question along the way but dont do the final exam.
2. Start from the beginning of the book again and work through it at a slightly faster pace. I found that I had forgotten a bit of the content from the first time through the book probably due to a memory overload.
3. Upon completion of the book for the second time and now having learnt and memorised the formulars and the use of Loading and CG systems you are good to sit the B.Tait Review Questions (chapter 8) and Final CPL exam.

This is what I remembered for use in the exam. When the clock started i quicky wrote them down:

Rate of Climb: CG=ROC/GS (I got a question on this).
Dist to ETP: Total Dist x GS Home / 2 x TAS
Time to PNR: SE x GS Home / 2 x TAS (very similar to ETP formular) Also remember a head or tail wind will always bring the PNR closer to the base. The stronger the wind the closer to base (regardless of whether it is head or tail).

Finding max payload: using the B.Tait diagram: I used acronym MAZPPPM
Shifting Weight: B.Tait Diagram and used acronym PPPRSDW (PPP Run So Damn Well)
Adding Weight: Same as shifting weight but change the D to a C. (PPPRSCW)
Weight to shift = change in moment index (x10,000) / Change in arm (i got this question). Easy mark!


Questions I remember getting:
About 3 on minimum fuel balast required after using hard ballast.
Surprisingly about 4 general terminology (ALA's, speed definition Vbe, Vne etc)
3 to 4 CG questions on the echo
About 1 each for the other take-off and landing charts(A,B,C)
Time/Dist to PNR about 3 questions and 1 on Dist to ETP

You pretty much need to know everything that Bob's book teaches. Take on the challenging questions when preparing, you'll be better for it.

Well I hope this helps and I'll take any tips in preparation for my last CPL exam, Air Law.

Regards
Daniel