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VOR Reciprocals

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antbar said:
My experience is that adding anything to anything in the cockpit while under the hood is nearly impossible for a task-loaded student, even if they have a Ph.D. in Mathematics.

I agree with the above statement 100%. So my question then is why so many people have these crazy ideas for some kind of methodology for coming up with reciprocals? Why not just use the memorization of the reciprocals such as I previously posted. Look there are only 18 combinations, much less than learning the multiplication tables as everyone must have learned in 4th grade. I mean there's only: 1-19, 2-20, 3-21, 4-22, 5-23, 6-24, 7-25, 8-26, 9-27, 10-28, 11-29, 12-30, 13-31, 14-32, 15-33, 16-34, 17-35 and 18-36. Example: 113-293, 144-324. It's just so easy this way, no math.

I've always done it this way and just thought everyone really did this too. Am I wrong or what? Am I the only one who does it the right way? Many of you on this board are very experienced, your comments please. Please tell these youngsters how to do this the easy way and the right way. There are no tricks; it’s just a matter of learning the reciprocal tables. And if you fly long enough you don't need to actually try to learn anything because you'll have been in enough airports with enough runways to automatically learn these reciprocals.

Comments/questions please……….
 
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I have him making flashcards. He says he is too tired after working to study. . .
When I learned this, I associated the reciprocals with familiar runways and thought about what the other direction was. . .pretty simple. . .never put much into all of the math stuff.

We flew again the other day and when told to intercept to 012 radial. . .. he put the 120 on the CDI, then the 060. . .etc. . .
 
I'm loving Undaunted's method, though I confess I have never bothered to actively attempt to memorize these pairs. It has happened naturally over the course of flying to a bunch of different airports, though. I have got to tell you that in my experience, getting an adult to do homework (especially if they already have their private license and already know everything about flying) is really, really tough. Even motivated adult students just want to go home and not think about VOR navigation for a while after buzzing around in the soup for two hours.

O.K., so when I'm teaching VOR navigation, there are a few things that must be memorized by my student, or I'm at a loss. They just have to spend 15 minutes REALLY THINKING about this, and it'll become clear.

Rule #1: RADIALS ARE FROM THE VOR (or other navaid).

Rule #2: ALWAYS SET YOUR OBS SO THAT YOU WILL WIND UP FLYING THE TOP, E.G. THE DG AND OBS MUST BE MADE TO LOOK ALIKE ONCE YOU"VE TURNED ONTO THE RADIAL IN QUESTION.

Rule #3: THEREFORE, IF YOU WANT TO GO TO THE VOR, YOU MUST PUT THE RADIAL NUMBER AT THE BOTTOM OF THE OBS, AND IF YOU WANT TO GO AWAY YOU MUST PUT IT AT THE TOP. "From-Top To-Bottom" is a little memory aid that some of my students have glommed onto. Get it? The radial number goes in the top of the OBS if you're going FROM the VOR, and so on.

Getting them to center the needle is on you.

Perhaps the most valuable thing I can suggest is get him the heck out of the airplane and into a simulator (a PCATD will do fine). The stress in the cockpit might be bugging this poor dude out, and he may be confusing the information the OBS is providing him with the information the HI provides. Not that I remember this from the silly things I did during my instument training or anything. So get him into a sim and set him up for some intercepts... show him where he is on the instructor's screen, the direction he's heading, and how that correlates to what his instruments say. Take the heat off, and he may have a breakthrough with minimal effort on your part. I remember getting really dumb really fast under the hood, and all students have these moments. Being able to sip a Coke and press "pause" can make all the difference.

Good luck. I know how painful this lesson can be.
 
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I went back and read your original description of the problem, and I'll bet he's trying to dial the heading of his intercept angle in on the OBS. Not that I ever tried to do that...
 
iflyabeech said:
I have him making flashcards. He says he is too tired after working to study. . .

Great idea.....And if he won't study to learn these recipricals, it's no recommendation. After all your reputation as a CFI-I is on the line when you sign him off. Tell him you won't take chances on a bust for such dumb things as setting the wrong inbound course. After all, it's your way only on this one. You, as the CFI-I have the power to say when he is ready. And in the end, your student will thank you for this.
 
UndauntedFlyer said:
Am I the only one who does it the right way?
Comments/questions please……….
There's a statement guaranteed to turn off the interested reader.

Mr. Undaunted Flyer, Sir, surely you realize that there are many different ways to do this or most other things in aviation. That's the primary reason we have "Standardization".

Standardization isn't the "only way", or "right way", it is a way that is agreed upon as usually being one of the best ways, so we use it as a standard by which to evaluate performance.

But there are many ways to do things, and each student is different.

Your method requires memorization, just the same as learning the multiplication tables. I have a real hard time with memorization. Learning the multiplication tables in school was a killer for me. Of course I eventually did, but I learn concepts very easily. I learned the concept of recipricals right away, and the memorization just came with continued use.
 
nosehair said:
I learned the concept of recipricals right away, and the memorization just came with continued use.

This is exactly the way most people learn the recipricals, by experience through flying to different airports with different runways and by simply using this to set the inbound courses from the outbound radials shown on charts. But in my view, this whole process can be accelerated by a good CFI-I instructor insisting that his/her student learn this memorization concept right away so they can perform as an experienced pilot on the flight test and therefore not make dumb "add 200 and subtract 20" math mistakes with the examiner. In my opinion, all experienced pilots use the memorization method to figure recipricals, whether they learned it though experience or right away I don't know, but I'm sure that a little memorization in the beginning would pay off. Does anyone disagree with this?
 

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