Navigation - Bob Tait Aviation Theory Forum

CPL CNAV exam apparent GPWT/GAF questions

James_Fatchen — Mon, 27 Apr 2026 00:49:12 +0000

Hi all,

according to my practise exam provider there is a possibility of GAF and GPWT questions in the CNAV exam! However there is nothing I can see in Bobs CNAV book that references GAF/GPWT, is this something I need to consider before sitting the exam?

thank you

CPL Nav workbook answers

jsheps16 — Fri, 30 Jan 2026 01:25:57 +0000

Hi there, I'm currently studying for CPL nav exam and I'm going through the workbooks. In the exercise workbook I'm getting a few incorrect answers when comparing to the answers in the back of the book. For example, on questions working out fuel burn, it says with litres work towards the nearest whole number, example 41lph burn rate and 45 mins final reserve, I get the answer as 30.75 which I round up to 31L. The answer however in the back of the book is 30L. This is one example of many that are coming up, am I just answering these wrong by not rounding correctly, or is there something I'm missing? Any help is much appreciated.

CNAV CPL - Navigation Equipment

Claudio — Mon, 12 Jan 2026 10:20:24 +0000

Please could I double check which equipment is required for CPL Nav. CASA website stipulates "Navigation equipment". My thoughts are: - EB-6 whizz wheel. Is this the recommended one? - Square navigation protractor. - Navigation ruler 1:1,000,000 calibrated to NM. I trust a electronic flight computer is not allowed?

CPL navigation

Ravi — Sat, 01 Nov 2025 12:00:18 +0000

Hi all, I have the Navigation text book Apart from the topics included in the book, are there other areas of the MOS that are examinable? I from the forum, fuel planning questions is a possibility Id be grateful if there is anyone who has recently sat the exam who can guide re. what to expect Also another question, re margin. I have the AC 91-15 c210 circular but the example is discretionary fuel is ) It states that the margin is total fuel - fuel required, but if you include discretionary fuel, then does that diminish the margin? there was no great clarity re over this Kind regards

AIP GEN 1.5 - 9

callum — Sat, 13 Sep 2025 13:02:45 +0000

Hello AIP GEN 1.5 - 9 no longer exists, not sure for how long I only got my AIP copy last week. The rated coverages for VOR / NDB are now listed in AIP GEN 1.5 - 2 para 2.3, this is incorrectly stated on pages 173 and 142 of the CNAV textbook. My bad, just read the document at the top of the errata page.

Combining Radio Navigation with the 1 in 60 Rule

callum — Sat, 13 Sep 2025 12:43:00 +0000

Hello Page 171 of the CNAV Textbook has an example question 1; in which the aircraft is both 20 DME from the station, and 20 degrees off intercept track. I was confused for a while by the HAT trick equation in this example - me thinking that the angle A had suddenly become a distance; not helped by the statement on page 157 that A is a displacement (implying some distance DME rather than a deviation off track), it's a good exercise in being discerning in reading the question, but perhaps a note about that wouldn't go astray in the next print?

CNAV Textbook Pg. 73 Q21 and Q23

callum — Thu, 04 Sep 2025 13:46:29 +0000

Hello again, Q21 the statement is true for 358/360 wind directions but what about when the wind is 100% headwind or9 tailwind? Q23 is missing it's third wind arrow Thanks, cal

Confusion w/ Fig 1.23 pg 13 CNAV Textbook

callum — Fri, 29 Aug 2025 12:50:08 +0000

Regarding conic projections, the description above figure 1.23 and 1.24 on pg 13 read to me that the standard parallels should be indicated one set below what they are indicated as by figure 1.23, figure 1.24 seems to contradict 1.23 immediately, demonstrating that the standard parallels indicated by 1.23 would actually represent the outer and second-most outer parallels in 1.23. Image hopefully explains it better than I could, please correct me if I am wrong, I feel like I'm not understanding a basic concept

Passed CPL Nav, and a summary debrief for everyone else!

Wai Yan Moe — Sat, 31 May 2025 14:12:23 +0000

Hi team, Just finished CPL Navigation - 5th out of 7th ticked off. Now CFPA and CALW left to go for! Good thing is CNAV is rather straightforward in comparison to other exams. You’ll be doing: - 1/60 ROC / RODs within a certain airspace requirement, making sure you either have airspace protection (remember that +500ft!) and or remaining OCTA - BOD and EOD calculations using lat and longs given by them. They’ll ask you for local times (with daylight savings so don’t forget to add +1 hours to AEST etc). When doing how many hours of daylight you have between two aerodromes, beware of the 10 minutes. You must plan to arrive 10 minutes prior, and that must be deducted from your hours of daylight question (i.e. 12 hr 5 mins vs 12 hr 15 mins) - Know the principles of lats and longs. Got a question (or two) asking for the direction the Earth spins (counter-clockwise from North), and how many minutes 1° of longitude takes (4 mins!). Keep those in mind. Know your meridians and parallels of latitudes for Equator, Tropic of Cancer / Capricorn and Great Circles. - Got a question in regards to VOR and NDB / ADF errors. Memorise the mnemonics by heart. NDB / ADF: MINTCHAT (Mountain Effect, Interference / Co-Channeling, Night Effect, Thunderstorms, Coastal Interference, Height, Aircraft Quadrantal, Terrain) and for VOR: AVGAST (Airborne Equipment, Vertical Polarisation, Aggregate, Site Effect, Terrain). I memorised GPS errors too (EMITRI) but didn’t see any GPS questions. Operational NAV: - Consult the ERSA for crosswind calculations / head wind / tailwind. Use your whiz wheel but double check with the ERSA (in GEN 2.7 I believe) - Only got 1 fuel calc question - and it was regarding safe endurance. Do note they WILL TRICK YOU. I almost got caught out the first time round, and only after reading the question the second time did I realise. They may ask for SAFE ENDURANCE WITH RESERVES. That means you don’t have to minus final reserve from your total fuel. Keep that in mind. - You will get USG > Litres / Kilogram conversions. Just refer to GEN 2.7 for that. - Got a couple of questions in regards to ERC L 4, asking for what frequency to contact for SARWATCH cancellation. - Used PCA to find out what kind of GAFs I’ll be flying through from A to B. Just draw a line and note down where you’re flying. (VIC, NSW-E, NSW W, etc) - Don’t forget to calculate for crosswind correction derived from crosswind, and the ETAS of it if >10°. Had two questions where I had to work it out. Numbers came within 1kt / 1° so don’t be too concerned with accuracy for this. The other MCQ choices were obviously wrong. - Note that GAF / GPWTs are True, and ATIS are Magnetic. Had a question where they gave just the W/V and you had to take those into account. Don’t get tripped up on that. - Know your 3 degree glide slope formula: 318 x NM out from threshold + Airport Elevation = Answer. - Remember what goes into usable fuel and what doesn’t. Know that final reserve is calculated using holding fuel consumption, and destination alternate is cruising fuel consumption. - Know your relative bearing / magnetic bearing / heading calculations and questions. Did 3 of those in the exam. Speed is of the essence here. Don’t get bogged down in the 1 markers. Personally I dove straight into the 2 markers first to get them out of the way, and then come back to the 1 markers. Double check your work, triple check your calculations if you have the time. They’re sneaky buggers and will penalise you if you’re a couple degrees / litres / off. Don’t give it to them. Happy for those studying to drop by and ask any burning questions, hopefully you aced this as well as I did! Godspeed.

Passed CPL Nav!

Nick Smit — Mon, 26 May 2025 01:35:53 +0000

Hello Bob, Referring to the below question, could you please confirm the correct answer is BNE Center 118.95. Your at St George on the ground and you want to cancel your SAR, what Brisbane frequency would you choose? ERSA Says FIA BNE Center 118.95 on ground. TIA