Need Help with Reciprocal Headings

[Stomp16]

Which is why the math is dumb. In the airplane... it's on the OBS/HSI. On the ground, who cares... you can even grab a calculator if you need to. I would never teach someone to do that in their head while flying. You have enough going on, arbitrarily adding one more thing doesn't make anything easier.

God forbid you teach someone to do simple math while flying. DDDOOOOOOOOOOOOOOOOOOOMMMMMMMMMMM!!!!!!!!!!!!!!11!!!!!!!!!1!!!!!!!!!!

 

[SIUav8er]

For those of you who cant add and subtract 2, there is always a real life official air force jet fighter pilot watch! it has a nifty slide rule/wiz wheel calculator! Its perfect for those tricky in flight calculations!

 

[granlistillo]

190/010 or so is where you have to add.

 

[CoffeeIcePapers]

God forbid you teach someone to do simple math while flying. DDDOOOOOOOOOOOOOOOOOOOMMMMMMMMMMM!!!!!!!!!!!!!!11!!!!!!!!!1!!!!!!!!!!

If they haven't learned how to subtract or add 180, then they probably shouldn't be flying, as it sometimes requires more than a 1st grade education.

 

[Vector4Food]

Yes I teach and use it.

For instance: if you want the reciprocal of 230....
Subtract 2 from the first digit=0
add 2 to the second digit= 5
answer 050

Same applies but reversed if total number is greater than 180.
For instance reciprocal of 050:
Take the first digit (0) and add 2= 2
take second digit (5) and subtract 2= 3
Answer:230

So it's either +2 -2 or -2+2

Ok how about the reciprocal of 290?

-2 from first digit = 0
Add 2 to the second digit?? = 1?

Reciprocal of 290 = 010?

It works up to 270, then it works again at 300...

280/290 doesn't work :

270=090 right
280=000 wrong
290=010 wrong
300=120 right

 

[beasly]

You are correct. I'll make an excuse and say it was because I was typing on an iphone

They should make an app for that.

 

[beasly]

For those of you who cant add and subtract 2, there is always a real life official air force jet fighter pilot watch! it has a nifty slide rule/wiz wheel calculator! Its perfect for those tricky in flight calculations!

I LOL'd at that. It took me a long time to learn ignore all those bells and whistles and keep it simple.

 

[Douglas]

Ok how about the reciprocal of 290?

-2 from first digit = 0
Add 2 to the second digit?? = 1?

Reciprocal of 290 = 010?

It works up to 270, then it works again at 300...

280/290 doesn't work :

270=090 right
280=000 wrong
290=010 wrong
300=120 right

2+9 = 11 so the one carries over.
290 = 110
-----
I too like the "plus two, minus two".

 

[Vector4Food]

Sorry my logical brain doesn't like the multiple "well in this case do this instead"

I just learned to add/subtract 180... it's really not that hard if you practice

 

[TFaudree_ERAU]

I just use runway numbers and stick a 0 at the end. I know that 22 is the other end of 4, 33 is the other end of 15, and so on and so on.

 

[derg]

If they haven't learned how to subtract or add 180, then they probably shouldn't be flying, as it sometimes requires more than a 1st grade education.

I guess I shouldn't be flying! Darnit! I should have gone into macramé handicrafts like momma told me.

 

[CzechAirman]

Doesn't Sporty's make a computer that figures that out for you? Would be much easier and faster than trying to figure it out in your head.

 

[Tram]

Hey folks, I used to always teach this little trick as a flight instructor, but since it's been a while now, I've forgotten it... say I'm wanting to figure out what the reciprocal is for a 135 Radial... I used to teach a Add 2 Subtract 2 trick... does anyone remember that one?

Yeh, add 2 take 2..

180
22
360

150
22
370

 

[z987k]

Doesn't Sporty's make a computer that figures that out for you? Would be much easier and faster than trying to figure it out in your head.

lol.. why would anyone buy such a worthless thing? My flight bag has too much in it as it is.

 

[X-Forces]

Yeh, add 2 take 2..

180
22
360

150
22
330

Fixed it for you.

 

[Tram]

Got something against flying 370?

Thanks

 

[derg]

You know what's funny is that when we're asked in the simulator to do a hold on a specific radial and I do the "head math", the instructor always wants to send me to the FMS for the answer instead of computing the answer myself and crosschecking with the electronics.

Good old fashioned math rocks. But is privy to computational errors.

Good old fashioned automation works. But is privy to GIGO errors.

 

[X-Forces]

Got something against flying 370?

Thanks

I like flying negative headings actually!

"Turn left heading -030"