IR trainee has trouble with math in the cockpit - advice?

RussR

RussR

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Russ
Hi all,
I have an instrument trainee that is showing some problems with essential cockpit math while flying, and I'm looking for advice.

He flies well, has a lot more hours than the usual instrument trainee, is in his 50s, otherwise successful, etc. But heading changes seem to stump him.

Typical example - partial panel, timed turns to headings. We're flying maybe heading 090. I ask him to turn right to heading 150. "How long do you have to turn for?" I ask, but he has a hard time coming up with the answer, stumbling over the math. Even if I break it down into its component parts it's a problem. "Okay, how many degrees do you have to turn?" More stumbling, and often once I get an answer it'll be incorrect. But once we do settle down on "60 degrees" then the next question - "How long is that at a standard rate" - is another hurdle to cross. To help himself, he has gone ahead and written down on his kneeboard some typical degrees/time scenarios (like 10 degree = 3 seconds, 20 = 7, etc.). But obviously he can't write down every possibility.

So I want to help him and am looking for some advice as to how.

I completely understand not being able to do "math in plane", I have problems with it sometimes myself, especially when busy or in a stressful situation. But his case seems to be rather serious, and could start causing some delays in his training.

This does seem to be a problem on the ground too, if I ask him the same scenario, so it's not just in the plane, but I do think that environment makes it worse.

Any ideas on how to help?
 
To do this sort of thing well in the airplane, I think it has to be second nature on the ground. It has to be an immediate response, how many degrees to turn then divide by 3. You also have to develop an intuitive feel for approximately how long it takes, i.e. 10 seconds for each 30 degrees, so that when (not if) you make a slip, you catch it immediately because it doesn't sound right. If it doesn't come easy, it's going to take too long in the plane where there's a lot going on.

So all I would say (and I'm not a CFI but being a university level physics teacher in this day when ~90% of gen-ed students are innumerate, I do sort of teach remedial math) is to have him practice timed turn problems on the ground over and over, until he can come back with the correct answer in a second or two. Not everyone is a whiz at math, but anyone can learn to do simple arithmetic in their heads. I could go off on a long spiel about how "feelgood" curricula in our elementary and K-12 schools are turning out generations of adults who lack basic math skills, but your trainee is in his 50s so unless he went to one of the early adopter schools as a child, that probably doesn't apply.
 
How many seconds to turn 180 deg?

Is the new heading more or less than 180?

By about how much? put finger or bug on new heading, estimate size of pie slice

Why are timed turns to headings such a big deal anyway?
 
When he is heading 090 and you ask him to turn to 150 without any questions from you, what does he do?

Bob Gardner
 
There are three kinds of people in this world: Those who can count and those who can't.
 
bobmrg said:
When he is heading 090 and you ask him to turn to 150 without any questions from you, what does he do?

Bob Gardner
Click to expand...

ASSUMPTION: STD RATE TURNS: 1 minute = 180 degree turn.
My DG has numbers every 30 degrees. each of these is ten seconds of turn.

90 ... 120 ... 150.

ten seconds once,
ten seconds twice.

20 seconds total.
 
I've got a lot of the same problem. What works for me is to take the math out of it and memorize times for common turns. So, 15 degrees is 5 seconds, 30 is 10, 60 is 20, 90 is 30.

Figuring out how many degrees without math is harder, but doable. Sometimes if the DG is covered I'll look at the VOR indicator and do it visually. For some reason if I can look at the indicator and visualize the difference between the two headings it's easier for me to double check with the math.
For example: 90 -> 150, look at the indicator, looks like about 60 degrees, does that make sense? Yep, 100 + 60 is 160, therefore 90 + 60 is 150.

I still hate having to do timed turns, though.
 
bluesky74656 said:
I still hate having to do timed turns, though.
Click to expand...

Maybe off topic, but I've yet to find an instrument student who didn't get a big boost in confidence when they determined how very accurately a timed turn could be if they did all the components right. It was always, "oh, wow! that's right on".

If the student has this issue,I'd be looking for other areas where a similar issue could arise. It may be this kind of person has to essentially memorize many scenarios as they have a hard time extemporaneously thinking them through. Kind of like Temple Grandin.
 
My fun with timed turns in my instruction was that we found the stupid ASSHTECH timer/clock in my plane was running SLOW. I punted and used my portable sprorty's timer instead.
 
flyingron said:
My fun with timed turns in my instruction was that we found the stupid ASSHTECH timer/clock in my plane was running SLOW. I punted and used my portable sprorty's timer instead.
Click to expand...

Is it that hard to count "one mississippi, two mississippi..."?
 
Simple: In a standard rate turn, the DG is a clock where the second hand runs at half speed. Quick approximations are ok.
 
flyingron said:
ASSUMPTION: STD RATE TURNS: 1 minute = 180 degree turn.
My DG has numbers every 30 degrees. each of these is ten seconds of turn.

90 ... 120 ... 150.

ten seconds once,
ten seconds twice.

20 seconds total.
Click to expand...

My question had more to do with overburdening the student's thought processes than with math. Maybe, if not interrupted with questions, he would do perfectly well. Not clear from the thread thus far.

Bob
 
A lot of folks do better multiplying by 3 than dividing by 3. Instead of 210-70=140/3=47, try 21-7=14x3=42. Yeah, it comes up a tad short, but if you have them start the clock once rolled in, and start the roll-out at the time, it gets 'em pretty close, and when doing timed turns, pretty close is generally close enough.
 
Presuming that he isn't using the Nav2 CDI, set it to the current heading. Then have him turn it to the new heading counting 10 seconds for every 30 degrees of rotation towards the new heading. Ballpark the extra few seconds to get to the neighborhood of the next heading. Counting, but no calculations other than adding a few seconds to a nice round number. Your 90 to 150 example becomes simple.
 
My advice is to drill, baby, drill--but on the ground, or using an FTD.

Not to be flip, but after 30 years of teaching, I'd suggest working a problem in a safe environment, to exhaustion, will help.
 
Last edited:
RussR said:
Hi all,
I have an instrument trainee that is showing some problems with essential cockpit math while flying, and I'm looking for advice.

He flies well, has a lot more hours than the usual instrument trainee, is in his 50s, otherwise successful, etc. But heading changes seem to stump him.

Typical example - partial panel, timed turns to headings. We're flying maybe heading 090. I ask him to turn right to heading 150. "How long do you have to turn for?" I ask, but he has a hard time coming up with the answer, stumbling over the math. Even if I break it down into its component parts it's a problem. "Okay, how many degrees do you have to turn?" More stumbling, and often once I get an answer it'll be incorrect. But once we do settle down on "60 degrees" then the next question - "How long is that at a standard rate" - is another hurdle to cross. To help himself, he has gone ahead and written down on his kneeboard some typical degrees/time scenarios (like 10 degree = 3 seconds, 20 = 7, etc.). But obviously he can't write down every possibility.

So I want to help him and am looking for some advice as to how.

I completely understand not being able to do "math in plane", I have problems with it sometimes myself, especially when busy or in a stressful situation. But his case seems to be rather serious, and could start causing some delays in his training.

This does seem to be a problem on the ground too, if I ask him the same scenario, so it's not just in the plane, but I do think that environment makes it worse.

Any ideas on how to help?
Click to expand...

Interesting problem. Is the training going ok otherwise? Holds going ok? Flying ILS to minimums ok? Is it just the math on the timed turns?

I also did my IR in my 50s. I have looked at threads on this subject and concluded that on average it takes more time than doing an IR in your teens or 20s. It took me more time than the minimum under the hood to "get it".

I also found that doing some tricks to be sure my brain was "turned on" such as getting enough sleep, having a cup of coffee, getting some cardio before flying helped my brain to work better. Flying with the brain "turned off" isn't a good idea!
 
I'm a math major and therefore I cannot do simple math. Seriously, I'm very analytical about math and it's a cluttered topic, there's a lot of stray thoughts that come in. Attempting to do math normally is challenging and I have to check and double check my work. Doing it while flying the airplane is overload.

The point is - that having been trained to think deeper in math, I can't unlearn what I know. I can't think shallow in math, there's too much that gets in my way.

What works better for me is just going straight to the answer with minimal math. I visually split the headings into groups of 30 degrees, giving me 5 major points to the left and 5 to the right with 180 being a special case. Now I can see the turn as 30 degree segments on the DG or a turnable compass rose ( E6B ). By adding or subtracting 10 degrees to each major point I can get within 5 degrees of almost any turn.

There are 10 seconds per 30 degree segment so 60 degrees = 20 seconds. 50 degrees would be 3.3 seconds less (16.7), 70 degrees 3.3 second more (23.3). I can't time it much closer, but then I can't fly the difference between 3 and 3.3 seconds in a turn anyway. It gets me close and once stable I can fine tune with the compass.

With practice, you can completely skip to the answer. I visually see that 90 to 150 is 2 thirty degree segments to the right, so the answer is 2 x 10= 20 seconds.
 
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bobmrg said:
My question had more to do with overburdening the student's thought processes than with math. Maybe, if not interrupted with questions, he would do perfectly well. Not clear from the thread thus far.

Bob
Click to expand...

Great question Bob, and a valid concern.

But, when I don't say anything, one of two things generally happen:

1 - he starts turning right away, as far as I know not looking at the clock or his current heading, etc., and not having a starting reference therefore sets himself up for a problem at the end of the turn, or:

2 - he flies straight ahead for a while trying to figure out how far to turn, but has trouble coming up with the right answer for long enough that at some point I have to prompt him.

I do like some of the suggestions so far, thanks everybody. I think I'll try the one about just doing 10 seconds for every 30 degres and estimating the rest, using an unused CDI or ADF card to figure it out. I think a visual approach like this might work.
 
Well, you could look at the clock with a sweep second hand (no DPE or CFI ever covers that up). Disregard the numbers on it while picturing the DG there instead. From the current heading (12 o'clock), estimate where the desired heading would be on the clock face and double the number of seconds from the 12 o'clock position. In the example, 150° is at the ten second mark, so twice that is a twenty second turn.

dtuuri
 
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I also did my IR in my 50s. I have looked at threads on this subject and concluded that on average it takes more time than doing an IR in your teens or 20s. It took me more time than the minimum under the hood to "get it".

I also found that doing some tricks to be sure my brain was "turned on" such as getting enough sleep, having a cup of coffee, getting some cardio before flying helped my brain to work better. Flying with the brain "turned off" isn't a good idea!

I agree with all of that
 
flhrci said:
DG failure in hard IMC?

David
Click to expand...

Yes. Screw the compass for turns. Once I understood the errors in the compass my strategy for all turns was to use timed turns and then let the airplane settle, check with compass while straight and level, and correct as needed with a timed turn.

I agree with the recommendation of drilling. flash cards would probably help.
 
flyingron said:
ASSUMPTION: STD RATE TURNS: 1 minute = 180 degree turn.
My DG has numbers every 30 degrees. each of these is ten seconds of turn.

90 ... 120 ... 150.

ten seconds once,
ten seconds twice.

20 seconds total.
Click to expand...

This is what I do, count the 30 degree sections as 10 sec. groups, then if it's a little more/less, just remember to add a little more/less turn. When you roll out, check the compass to see how close you are and make fine adjustments.

I find it easier when ATC is giving instructions, you don't necessarily have a lot of time to figure the math in finer detail always.
 
flyingron said:
ASSUMPTION: STD RATE TURNS: 1 minute = 180 degree turn.
My DG has numbers every 30 degrees. each of these is ten seconds of turn.

90 ... 120 ... 150.

ten seconds once,
ten seconds twice.

20 seconds total.
Click to expand...

RussR said:
I think I'll try the one about just doing 10 seconds for every 30 degres and estimating the rest, using an unused CDI or ADF card to figure it out. I think a visual approach like this might work.
Click to expand...

It worked! Went flying yesterday, explained this to him on the ground first, he tried it in flight and it was like the most amazing light came on. He did great, and actually commented about the simplicity of it - "Heck, I can do THIS, it's easy!" Of course, now he thinks I'm some kind of educational wizard, even though I let him know the idea was not mine, but I sure like the method too.

We tried a few turns, both from "big numbers to big numbers" and also intermediate values, and it worked very well. For intermediate values, I just had him use the nearest 5 seconds. What with all the other factors involved, like rate of roll into and out of the turn, precision of the standard rate turn, when the clock was started, etc., it wound up just as close as any other method I've used.

So the visual method was an excellent idea, thank you very much for your help. It was neat seeing it click.
 
Yes, the DG was covered for these manuevers, and he used whatever other reference was handy...(2 CDIs and 1 ADF card)
 
RussR said:
It worked! Went flying yesterday, explained this to him on the ground first, he tried it in flight and it was like the most amazing light came on. He did great, and actually commented about the simplicity of it - "Heck, I can do THIS, it's easy!" Of course, now he thinks I'm some kind of educational wizard, even though I let him know the idea was not mine, but I sure like the method too.

We tried a few turns, both from "big numbers to big numbers" and also intermediate values, and it worked very well. For intermediate values, I just had him use the nearest 5 seconds. What with all the other factors involved, like rate of roll into and out of the turn, precision of the standard rate turn, when the clock was started, etc., it wound up just as close as any other method I've used.

So the visual method was an excellent idea, thank you very much for your help. It was neat seeing it click.
Click to expand...

I sure have gotten great help from this and other forums! I am glad that you found a suggestion that worked!
 
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