Big MAC?

Finally, a place for sport pilot instructors and/or wannabees to talk about instructing.

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Jim Hardin
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Big MAC?

Post by Jim Hardin »

Teaching as well as using Weight and Balance to determine CG is always interesting...

I prefer using the Station and CG envelope in inches rather than Moment/1000. But Station can get interesting if the forward GC limit is not fixed. Then you have to interpolate the results to make sure you are still in there.

Only had to use % of MAC once. Student had a Stinson 108-3 and that was the first time since studying for my ATP that I ever used it. I couldn't see any practical advantage to using it.

Open end discussion, what do you guys think? :D
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drseti
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Re: Big MAC?

Post by drseti »

As an engineer, I find % MAC very useful. And I teach it. Very simple if you have a Hershey-bar wing, where chord us constant over the entire wingspan. Much more difficult with a swept, tapered, or semi-tapered wing requiring you to integrate the area under the curve and divide the integral by the span to establish the mean. :x
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Prof H Paul Shuch
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Atrosa
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Re: Big MAC?

Post by Atrosa »

drseti wrote:As an engineer, I find % MAC very useful. And I teach it. Very simple if you have a Hershey-bar wing, where chord us constant over the entire wingspan. Much more difficult with a swept, tapered, or semi-tapered wing requiring you to integrate the area under the curve and divide the integral by the span to establish the mean. :x

WHAT!!! calculus. That's it I'm quitting becoming a pilot and joining the youth by being hypnotized by my phone.
TimTaylor
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Re: Big MAC?

Post by TimTaylor »

Atrosa wrote:
drseti wrote:As an engineer, I find % MAC very useful. And I teach it. Very simple if you have a Hershey-bar wing, where chord us constant over the entire wingspan. Much more difficult with a swept, tapered, or semi-tapered wing requiring you to integrate the area under the curve and divide the integral by the span to establish the mean. :x

WHAT!!! calculus. That's it I'm quitting becoming a pilot and joining the youth by being hypnotized by my phone.
That's why I switched from Aeronautical Engineering to Industrial Engineering at NCSU. Two years of chemistry, calculus, and physics was enough. An MBA from Wisconsin was easy after all that.
Retired from flying.
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Jim Hardin
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Re: Big MAC?

Post by Jim Hardin »

No pain, no gain :P
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foresterpoole
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Re: Big MAC?

Post by foresterpoole »

TimTaylor wrote:
Atrosa wrote:
drseti wrote:As an engineer, I find % MAC very useful. And I teach it. Very simple if you have a Hershey-bar wing, where chord us constant over the entire wingspan. Much more difficult with a swept, tapered, or semi-tapered wing requiring you to integrate the area under the curve and divide the integral by the span to establish the mean. :x

WHAT!!! calculus. That's it I'm quitting becoming a pilot and joining the youth by being hypnotized by my phone.
That's why I switched from Aeronautical Engineering to Industrial Engineering at NCSU. Two years of chemistry, calculus, and physics was enough. An MBA from Wisconsin was easy after all that.
I thought I was getting into a mathematical dessert when I started in forestry, fast forward 2 decades: Between business planning on 600,000 acres of timberland, manufacturing quality control oversight at three of the largest wood products mills in the country, and a host of other pet projects like real estate finance, I live in an excel sheet, linear/conditional programming, and SAS (a stats program). My head hurts.... :D
Ed
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drseti
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Re: Big MAC?

Post by drseti »

foresterpoole wrote: I live in an excel sheet, linear/conditional programming, and SAS
Ah, SAS - you're bringing me back to the 1970s!
The opinions posted are those of one CFI, and do not necessarily represent the FAA or its lawyers.
Prof H Paul Shuch
PhD CFII DPE LSRM-A/GL/WS/PPC iRMT
AvSport LLC, KLHV
[email protected]
AvSport.org
facebook.com/SportFlying
SportPilotExaminer.US
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