Trig functions & Private Pilot Test

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Nochmal

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I scheduled my written for tomorrow and just called the exam place to confirm whether or not I can use a trig calculator on the exam. It was a little unclear in some of the way the regs are written.

Answer: No, I cannot use the trig calculator, but I can use an aviation-specific calculator that does all the calculations for you like magic in a black box. Or you can use an E6B which is a piece of **** and hard to be accurate with.

That is frankly, stupid. So, those of us who do calculations from first principles are disadvantaged to those who spend some extra money and buy and learn how to use a device that takes all the understanding out of it.

Sorry, this is just a rant, but man am I angry...
 
yep, sounds like you're an angry person. don't think I used a calculator on either written I took.
 
What in tarnation do you need a trig calculator for? The e6b is about as simple as it gets, most of which are basic mental calculations.
 
Took mine Sunday. Got an 88 with basic math calculator, E6B and Plotter.
 
Didn't your CFI go over what you needed?
 
On the Sporty’s practice tests there are always questions like:

Given wind X at Y and true air speed Z, how long will it take to fly from A to B.

Or:

What is the crosswind component on runway A if wind is X at Y.

Or anything to do with wind impact to flying...

Yes, an E6B will do it. Painfully, slowly and inaccurately. A trig calculator will do it swiftly, easily and accurately if you know basic vector algebra.

Also, if you’re right and I don’t need it, why ban it?
 
As for CFI, I used the calculator in front of him and asked if it was ok. He said yes, especially since you are allowed to use an aviation calculator that does it all black-box anyway.

Guess pilots who do vector algebra are rare...don’t think he’d ever seen one before.
 
Nochmal said:
On the Sporty’s practice tests there are always questions like:

Given wind X at Y and true air speed Z, how long will it take to fly from A to B.

Or:

What is the crosswind component on runway A if wind is X at Y.

Or anything to do with wind impact to flying...

Yes, an E6B will do it. Painfully, slowly and inaccurately. A trig calculator will do it swiftly, easily and accurately if you know basic vector algebra.

Also, if you’re right and I don’t need it, why ban it?
Click to expand...
And all of those things are done within just a few turns of the e6b disk. Very quick and efficient. Sounds to me like you just don’t understand how to use it.
 
One other thought - don't ask if you can bring a "trig calculator" but rather bring a calculator. I think you can bring a calculator with a memory as long as you can demonstrate that it has been cleared. No pun in intended, but I think a remember seeing that in one of the test prep sites.

Having said that, cross wind component, WCA and ground speed is dead nuts easy on the paper table and E6B.
 
Nochmal said:
I scheduled my written for tomorrow and just called the exam place to confirm whether or not I can use a trig calculator on the exam. It was a little unclear in some of the way the regs are written.

Answer: No, I cannot use the trig calculator, but I can use an aviation-specific calculator that does all the calculations for you like magic in a black box. Or you can use an E6B which is a piece of **** and hard to be accurate with.

That is frankly, stupid. So, those of us who do calculations from first principles are disadvantaged to those who spend some extra money and buy and learn how to use a device that takes all the understanding out of it.

Sorry, this is just a rant, but man am I angry...
Click to expand...
They are concerned that it may have memory to store answers in and that the test center won’t be able to tell the difference.
 
Hang 4 said:
One other thought - don't ask if you can bring a "trig calculator" but rather bring a calculator. I think you can bring a calculator with a memory as long as you can demonstrate that it has been cleared. No pun in intended, but I think a remember seeing that in one of the test prep sites.

Having said that, cross wind component, WCA and ground speed is dead nuts easy on the paper table and E6B.
Click to expand...
My test center would not allow any outside calculator, but they let me use theirs if I wanted to.
 
Hang 4 said:
One other thought - don't ask if you can bring a "trig calculator" but rather bring a calculator. I think you can bring a calculator with a memory as long as you can demonstrate that it has been cleared. No pun in intended, but I think a remember seeing that in one of the test prep sites.

Having said that, cross wind component, WCA and ground speed is dead nuts easy on the paper table and E6B.
Click to expand...
However....the testing site has the option to allow or disallow any electronic calculator, even if the FAA says it's ok to use. Details in the tiny small print somewhere in the FAR or AIM, I don't remember which.

As for an E6B - PITA. I still have my K&R slide rule Dad bought me when I started engineering school. Never learned to use it. The manual E6B is just another version of a slide rule. There are too many other resources to be limited to the slide rule. Fortunately, most E6B have the instructions for wind calculations printed on them, which is legal for all exams. That's right - if your E6B has the details, they can't disallow it.

On the other hand, the trig/wind problems can be fairly well managed by remembering this:
45 deg is 0.707 (sin or cos)
30 deg sin = 60 deg cos = 0.5
30 deg cos = 60 deg sin = 0.87

Don't remember the triangle picture for sin & cos? NASA has great examples.
 

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Nochmal said:
Guess pilots who do vector algebra are rare...don’t think he’d ever seen one before.
Click to expand...

<Raises hand emphatically!>

The two "trig-giest" easy calculations that come to mind are:
Crosswind component = Wind * sin(angle)
Load factor = 1/cos(bankangle)
The FAA seems to want candidates to solve both of these problems by squinting at a graph of some sort. But it's WAY easier to just do it on a scientific calculator. If you know your trig.

Groundspeed/Airspeed/Wind-correction problems are more complicated. But still, why not let candidates do math problems using the tools that they know best? Maybe for you, that's the slide rule, but maybe it's your trusty HP 15C.
 
kath said:
<Raises hand emphatically!>

The two "trig-giest" easy calculations that come to mind are:
Crosswind component = Wind * sin(angle)
Load factor = 1/cos(bankangle)
The FAA seems to want candidates to solve both of these problems by squinting at a graph of some sort. But it's WAY easier to just do it on a scientific calculator. If you know your trig.

Groundspeed/Airspeed/Wind-correction problems are more complicated. But still, why not let candidates do math problems using the tools that they know best? Maybe for you, that's the slide rule, but maybe it's your trusty HP 15C.
Click to expand...

Thank you...mostly I posted to hopefully find out I wasn't alone. I'll go slog my way through the 1920s approach with a slide rule. Grin and bare it while my trusty HP 32S (I had a 15C but gave it to my sister when I went to grad school and she was in college) sits in the car. :(
 
Nochmal said:
I scheduled my written for tomorrow and just called the exam place to confirm whether or not I can use a trig calculator on the exam. It was a little unclear in some of the way the regs are written.

Answer: No, I cannot use the trig calculator, but I can use an aviation-specific calculator that does all the calculations for you like magic in a black box. Or you can use an E6B which is a piece of **** and hard to be accurate with.

That is frankly, stupid. So, those of us who do calculations from first principles are disadvantaged to those who spend some extra money and buy and learn how to use a device that takes all the understanding out of it.

Sorry, this is just a rant, but man am I angry...
Click to expand...

I am surprised that you need a trigonometric calculator (whatever that is) to do these problems. You should know the sine and cosine values of common angles, and be able to interpolate. These are multiple choice answers, so you just need to get a ballpark answer to hit the right one. I took all my FAA exams without any calculator (I might have carried an E6B for the private - can't remember, it was a long time ago).

FWIW, professional engineering licensing exams will list the specific model of calculators you can bring. There is a good reason for it. The goal is not only to find out if you can do the problems, but whether you can do them under a given circumstance. So by allowing any aviation-specific calculator, the FAA is actually being very generous.
 
My favorite trig memory aid:

trigonometry_sin_cos_tan_of_common_angles_2.png

Notice how they are all something divided by two, and each follows a pattern in the numerator: sqrt(0), sqrt(1), sqrt(2), sqrt(3), sqrt(4) for sine, and the other way around for cosine....
 
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Aww, come on, if you can use one to navigate a starship, it should be fine for anything on the written test....

e6b.jpg
 
I have about the equivalency of a second grade math level. I did not need anything that fancy for flying, ever.

And the CFI should have known calculators that store any information are not allowed. It's manual E6, Electronic E6, or just a plain old calculator. It's been that way for a long time. Probably longer than the CFI has been alive.
 
The OFFICIAL answer to your question is you must call the testing center. The FAA now gives them the discretion to determine what calculators if ANY are allowed.

ACCEPTABLE (according to the FAA):
Calculators with simple programmable memories, which allow addition to, subtraction from, or retrieval of one number from the memory; or simple functions, such as square root and percentages

NOT ACCEPTABLE:
Magnetic Cards, magnetic tapes, modules, computer chips, or any other device upon which prewritten programs or information related to the test can be stored and retrieved

I have used a simple scientific (cheapo) calculator with trig functions at PSI.
 
What is a trig calculator?

I used a basic scientific calculator which had trig functions on it on every written I've taken. Which is a lot.
 
The test doesn't matter. It has nothing to do with what you may or may not do in an actual airplane in the actual air.

You just have to have enough stuff memorized to pass, then you are done with it.
 
dmspilot said:
What is a trig calculator?

I used a basic scientific calculator which had trig functions on it on every written I've taken. Which is a lot.
Click to expand...

And denver has written........A L O T.
 
Nochmal said:
I scheduled my written for tomorrow and just called the exam place to confirm whether or not I can use a trig calculator on the exam. It was a little unclear in some of the way the regs are written.

Answer: No, I cannot use the trig calculator, but I can use an aviation-specific calculator that does all the calculations for you like magic in a black box. Or you can use an E6B which is a piece of **** and hard to be accurate with.

That is frankly, stupid. So, those of us who do calculations from first principles are disadvantaged to those who spend some extra money and buy and learn how to use a device that takes all the understanding out of it.

Sorry, this is just a rant, but man am I angry...
Click to expand...
I tried to bring my RPN hp calculator into my IR written, it does trig among other things, the told me if he doesn't understand it I couldn't use it, lol.
 
kath said:
My favorite trig memory aid:

View attachment 64204

Notice how they are all something divided by two, and each follows a pattern in the numerator: sqrt(0), sqrt(1), sqrt(2), sqrt(3), sqrt(4) for sine, and the other way around for cosine....
Click to expand...
But how many people remember the sqrt of 2?
 
Capt. Geoffrey Thorpe said:
The test doesn't matter. It has nothing to do with what you may or may not do in an actual airplane in the actual air.

You just have to have enough stuff memorized to pass, then you are done with it.
Click to expand...

My wife has taken to calling the written The Pilot Hazing...it appears to serve no other purpose.
 
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Nochmal said:
My wife has taken to calling the written The Pilot Hazing...it appears to serve no other purpose.
Click to expand...
The purpose is to get people to learn the material. The fact that many people study for the test rather than learning the material is what defeats it's purpose.
 
Sorry to be combative, but I feel that if you’re not smart enough to use an E6B, you should probably do yourself and your potential passengers a favor, and find something to do with your time other than flying.

Edit:

I am not saying you are unsafe if you don’t know how to use a whiz wheel, or never bothered to pick one up. I am saying that if you are incapable of learning to use it if you try, then you have limited mental capacity.
 
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Go to a laser grade, you don't need a calculator at all, the onscreen one has most every formula programmed into it.
 
murphey said:
On the other hand, the trig/wind problems can be fairly well managed by remembering this:
45 deg is 0.707 (sin or cos)
30 deg sin = 60 deg cos = 0.5
30 deg cos = 60 deg sin = 0.87
Click to expand...
Precisely. It's a Feynman in Brazil sort of thing.

BTW, speaking of first principles. Russian pilots do not have E6B, and never had. They use a linear slide rule, which also doubles as a ruler on the map. Also, when they calculate W&B, they compute a real %MAC. Are their safety record or efficiency any better than ours?
 
If you fail due to getting the “trig” questions wrong then there’s a lot more to review :D
 
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