Electronic Flight Computer-QXC

[al_renko]

Hi all,
Please can someone out there confirm if it is permissible to use the Electronic Flight Computer for the qualifying cross country flight (QXC),thanks,
Al.

[riverrock83]

I shall repeat myself.

You should prepare the navigation in the way you were taught by your instructor (using whatever method was taught),

If your instructor says its fine - then go for it. As far as I know, how you work out your navigation isn't stipulated. How you work out your route before you fly isn't what the QXC is testing (thats what the nav exam is for). Its testing your ability to fly to your plan as you were taught and deal with a real world flight on your own.

[BackPacker]

Agree. If you present a complete plog to your instructor before the QXC, and he finds nothing wrong with it, he really doesn't (shouldn't) care how you derived the data.

It's only when he finds a fault with it, that he may consider it a learning opportunity and will ask you to demonstrate how you derived the (wrong) values.

[al_renko]

electronic flight computer

thanks for your response,in other words "yes"

[al_renko]

electronic flight computer

hi all,
when i was in oudtshoorn a couple of years ago i recall students from the larger neighbourhood kept pestering me for the cx-2 when preparing there vfr log,cheers,
Al.

[peterh337]

In the UK PPL, the circular slide rule used to be mandatory when I did the PPL in 2000/2001, and much time was wasted learning it which would have been put to much better use in the (otherwise non mandatory) ground school.

If they have done away with the slide rule, that is super, but I wonder how that will work in the nav exam, whose multiple choice options were rigged around the slide rule results and perhaps none of the answers will be right (or more than one may be equally off) if the result is worked out precisely.

[Gertrude the Wombat]

much time was wasted learning it

?? - one side is simply a circular slide rule, like the one I had at school, so zero minutes to learn it, and the other side is a lot quicker and easier than trying to either (a) draw and measure wind triangles by hand or (b) do the trig calculations.

[riverrock83]

Originally Posted by Gertrude the Wombat

like the one I had at school

Use of slide rules haven't been taught in schools for something like 30 years (at least - certainly before my time!). The whole concept was alien to me when I started flying training, although now I get the concept I can do speed/distance/time calculations much more quickly on the slide rule than I can electronically.
On the wind side, the inaccuracy is annoying to me although considerably quicker than doing the maths (and certainly more accurate than I can fly and winds predictions!).

I understand that slide rules aren't in theory compulsory but since you aren't allowed to take a programmable calculator into JAR exams, it would be pretty much impossible to complete some of the papers without one.

[peterh337]

I used a normal slide rule at school, too, in the late 1960s, so I know exactly how it works, but that's irrelevant.

For straight mult/div, a normal calculator is far better in every way.

For wind calcs, one would use a dedicated E6B calc, but those may be banned. I don't know...

[RTN11]

a dedicated E6B calc, but those may be banned

Certainly banned for any written test for PPL, CPL, ATPL & IR exams, but for any PPL nav flight you can plan any way you like. It's really down to the instructor to nurture the correct way to plan flights.

I would always start by teaching the fundamentals of the triangle of velocities. Depending on someone's knowledge of maths, this can simply be mentioning it and them nodding, or having to actually go through trigonometry. Once they realise where the figures are coming from I would go through the manual flight computer, since this shows the triangle of velocities reduced down to something useful and manageable and reinforces the fundamental point.

Once they have completed the Nav exam, possibly after the QXC I would then encourage the use of electronic planning tools, since this is more what they will use in real life. However, they still need the fundamental understanding from the onset of where these figures are coming from and how to do a rough calculation in their head.

With any computer it's rubbish in, rubbish out so be careful when you're planning that you don't end up with a useless plog through a silly typo.

[SEP Flyer]

Have a look at the Knightson Computer - it is the easiest to use navigation tool I have ever seen, no moving parts, no batteries and for diversions (and indeed main planning) a no brainer. And, as far as I know, it is approved by the CAA for use in the skills test.

I don't really understand why it isn't better known!

It costs £10 and you can get it directly from the inventor Mark Knight - www.knightson.org.uk

I don't work for and I'm not connected to them, so hopefully not breaking any pprune ad rules by posting this, but I have just been so impressed with it!

It is so simple.

[Whopity]

Yes, in theory you could use an Electronic Calculator for the QXC but for heavens name WHY? Learning to fly is about learning the basic skills associated with flying an aeroplane. You should be able to calculate your QXC plog simply by rule of thumb, and using the computer between your ears. If you are dependent upon electronic gadgetry at this stage, you are probably pursuing the wrong hobby.

[BackPacker]

As others have said, with all the numbers in a typical plog, the "garbage-in, garbage-out" risk is very real. For me, it means that any method that *only* has me input numbers, and give me numbers as output without a visual check as to whether stuff makes sense, is a big no-no.

So for my flight planning needs I use both ends of the scale, but not the bits in the middle:

One end of the scale which works for me, is the PPL-taught way of doing things. Line on the map, use ruler and protractor to measure distance and true track, use the E6B to convert into magnetic heading and ETE. When doing this I can continuously visualize what I'm doing and whether I'm correcting for drift the proper way. And there are various other gross error checks built-in as well.

At the other end of the scale is a full-blown navigation package. SkyDemon in my case, but anything electronic that allows you to see your full route on an electronic map, and which outputs a complete plog would be fine. As long as I can see a line from my departure to my destination, and see in the plog that the (downloaded) wind values are more or less in line with what I would expect, I can be reasonably sure the magnetic headings and ETEs that the program calculated are correct.

But I don't like anything in between, such as a CX2 or any of these iPad/iPhone "E6B" calculator apps. The risk of input/output errors is too big for my liking, and there are no implicit gross error checks built into the complete method.

[al_renko]

Electronic Calculator

hi there,
thanks for your response,i am not talking about throwing away the charts etc,i can asure you i have more conventional gadgets to plan the prog with,the whizz wheel doesn't have batteries granted,but if you input the wrong figures,therefore,it also follows you will get the wrong output,or am i missing something,cheers,
Al.

[RTN11]

i am not talking about throwing away the charts etc,i can asure you i have more conventional gadgets to plan the prog with,the whizz wheel doesn't have batteries granted,but if you input the wrong figures,therefore,it also follows you will get the wrong output,or am i missing something

The main thing is that there is some process taking place, you drawing the drift onto the wind side of the calculator, twisting it round, thinking which way you need to twist it, probably looking at a chart to double check your thinking.

With an electronic calculator or computer program, you can just push a few buttons and get an answer without seeing the process which took place so it is much easier to end up with a gross error (180 degrees out, wind applied the wrong way etc).

Having said that, I had one student who would frequently mis-use a protractor ending up with a 180 degree error, or sometimes 90 degrees, or apply the wind from the wrong direction (thinking the bearing was where it was going) leading to similar gross errors.

[peterh337]

Whopity is spot on in that the thumb rule (max drift is half the crosswind, or whatever) is good enough for PPL level flying (dead reckoning).

This is because a) most people fly with non-slaved compass (DI) systems whose gyros are shagged and b) the forecast winds aloft are usually way off.

But one has to pass the exams somehow, and the options are rigged to assume the use of the slide rule and in particular the second (iterative) step. I think there is an alternative way to use the slide rule which avoids the iterative step(s) but it isn't normally taught and would probably fail you the exam

Similarly if you do the trig with a calculator (which is pretty trivial) you might fail the exam if they give you two answers 2 degrees apart and your calculation lands between the two

[Johnm]

The techniques taught for ground exams have little or no relevance to how one actually operates an aeroplane in practice. Do the exams as they are taught and remember each licence and rating award just opens the door to learning how to do it properly!

I no longer possess a whizz wheel and can't remember how to use one and while I have several gadgets that would do E6B I've never used it.

Curiously enough I can still plan and execute both VFR and IFR flights because I use software tools and GPS!