ATPL Nav

[rocket66]

Gday all

I have just sat ATPL nave for the seconn time and failed it AGAIN. I have only failed one ather exams in the whole ppl, cpl, irex lot and went into this exam confident I'd be ok to pass.

I'm keen to hear any stories and/or hints/tips that I may be able to use. $151 per exam with a mortgage is getting a bit nuts.


Rocket

[Bug4514]

Hey having the same problem.I do very well in all practise exams but bomb out in the real one.

[MikeTangoEcho]

what does ya kdr say? i had the same prob with cfpa

[DUXNUTZ]

Hi there.

I'm also having issues with Nav.

Specifically, working out if your true Alt is higher or lower than ILS glidescope and the how's of working that out.

Also the Great Circle being concave to the parallel of origin etc. Can't find a picture of what that looks like.

Need help!

Cheers

-Dux

[astroboy55]

the sad thing is, there's a good chance that you're not actually failing. The ATPL exams are famous for having either the incorrect answer listed as correct in the database, or not displaying the correct answer in the options at all. I remember when I sat Systems, there were so many incorrect answers in the exam, that we took it to CASA, and they changed the answers to around 15 questions that our group had seen. Ridiculous for a 'professional' organisation.

[Queenslander]

ATPL exams are not the only database that is full of incorrect answers, the CPL and IREX databases are also full of the wrong answers........ Must be a money making exercise again, making us resit the exams again:{

[Mattoosular]

Hey,

I too had problems with Nav. Failed the first time, passed second time in 90's. I posted a thing on here about it entitled "ATPL Navigation question" and "antenna polarisation".

The responses I got from these posts were very helpful, and quite pertinent to the CASA exams. With regards to finding the True Altitude, unfortunately you have to be quite accurate to achieve the correct answer; this too applies to PSDs (I thought what I was doing was wrong, when in fact I was just being inaccurate). If you have any specific queries I'll do my best to help as I jotted down a few notes from the actual exam (that is, as soon as I get this air law exam done tomorrow).

[rocket66]

Thanks for all the replies troops, I recall I did go into the first one under prepared and failed. I was determined not to fail the second one and felt confident going in I would be successful.

I began with the 3 pointers then moved to the 2 pointers and completed the 1's easily. I answered all bar 2 questions without hesitation and still didnt get through.??

All the practice tests come through in the 90's that I have done so I have no idea. I hadnt considered questioning the exam answers but will certainly be contacting my good friends at my local CASA branch to see if the can offer any information:ugh:.......as best I can without paying a fee!


Rocket

[ReverseFlight]

I found this subject to be the second most difficult after Flight Planning. There is very limited time and you have to work very fast with your calculations. Better still, elimination of unlikely answers (working backwards) saves time and preserves brain power for the more tricky questions.

Wishing you third time lucky, mate. :ok:

[Ox cidental]

Rckt66,

Don't let it get you wound up. I fluffed NAV and was determined the question was f$%ked up, as I keep the working on my chart and reviewed it. Still, copped it on the chin.

Gave Nav a rest and went through 2 other exams before coming back to it slightly refreshed. Do gross error checks on the questions and your answers. Don't read into it any unnecessary complications.

Third ones the charm.

Ox cidental

[FOD Hazard]

Hi Team, I have been trying to get through the nav stuff.The ones Im having difficulty with don't seem to have any good worked examples in teh AFT notes. Can i please get some advice on the question below?

Q: You are cruising at A070 directly above a mountain of elev 6420ft. The QNH is 1001 hpa with an OAT of -14 deg C. The radio/radar altimeter would indicate:

a) 188ft
b) 972ft
c) 390ft
d) 580ft

Apparently it is a). I was happy to remove b) and d) based on the temperature being colder than ISA (hence the altimeter overreading & the true alt being below the indicated)...but I can't work it out.

Some of the ILS above or below ones are brain breakers too...can't get the exact answers...which makes me doubt my method.

Any help on the above question would be greatly appreciated. There is a beer in it for someone in Darwin.

[VIMD]

From a few quick calculations (as I do not have a whizz wheel with me), I get close to a).

Pressure altitude for the high ground is 6,780ft, which gives an ISA deviation of -15 if you round to the nearest degree. A rule of thumb for the extent of temperature error is 4% per degree of ISA deviation per thousand feet of indicated altitude.

4 x (-15) x 7 = -420ft

The true altitude is thus 420ft lower than indicated, so terrain clearance is:

6,580ft (true alt) - 6,420ft (elev) = approximately 160 ft

[Oktas8]

The ILS ones can be mind twisters, because you are at the correct height (on glideslope), but the altimeter is telling lies. This is the opposite of the 7000'-over-a-mountain scenario that you posed above.

Try drawing a picture, runway, glideslope, aircraft on glideslope with true height written in. This helps me to avoid the problem of applying the correct equations in the wrong sense.

Best of luck,
O8

[Louised]

It's interesting to read all these responses! I had given up on ATPL's
many years ago, due to failing my systems exam by 1%....and decided
back then that I was not going to attempt them anymore! I had sat a lot of other
ATPL subjects and passed! Now I need to start again...as its been a while! But I wish I kept going! To think I can get HD for uni exams....and put in less effort, and study sooo hard for ATPL's and it's a battle between I and a database with incorrect answers! It's ridiculous and such a huge cost! The days of sitting my cpl and irex at mascot Sydney, written exam, without such a ridiculous amount to pay! Times have changed! It's only been 5 years out of instructing, and it's soo expensive to do anything related to aviation! But I have decided that I am going to give it another go!! I guess when you have a mortgage- responsibility changes! But I don't want to look back later in life and say I should of just given it another go!!!

[Kopity]

I have come across this question too and find it a little confusing..

The book I'm studying from says:
-Find pressure altitude
-Then find indicated height AGL
-Set pressure altitude against airport temp.
-on the outer scale of the whizz wheel, read true height AGL, opposite indicated AGL
-If necessary, add airport elevation to true height AGL to get true height AMSL.

So with this question I would have thought you would set -14 against the pressure altitude of 6,780ft and read off a figure opposite 580ft on the outer scale.

But obviously that is wrong as being approx ISA-15, one would expect the altimeter to over-read by more than the answer of 560ft AGL this method yields.

[Kopity]

I borrowed old charts as surely they don't re-write the questions every time an airway changes! Worked for me for flight planning and nav with no issues. My AIP and ERSA were also from 2011, and I used them for law and nav with no issues. I sat nav a couple of months ago. Don't think I actually had any questions from the AIP or ERSA in my nav exam at all, but you can get VOR/ NDB rated coverage questions I think