Koch Chart variability

[CerroTorre]

Ok, my anal-retentivity (is that a word?) continues:

In the Instrument Flying Handbook, the Koch Chart on page 4-6 gives completely different outputs than any other Koch Charts I find. That seems like I’m looking at a misprint and not a sign that I’ve misunderstood how this particular chart works

My understanding of a Koch Chart is that it should be applicable regardless of (normally aspirated) aircraft type. In other words, it just tells you the impact on performance ... for all normally aspirated aircraft.

But based on this chart, either I am misunderstanding something significant, or the chart is wrong.

59F and 0ft pressure altitude indicate a 20-25% increase in takeoff distances. So ... standard conditions at sea level ...

If I’m correct then it’s textbook errors like this that make self-taught learning a nightmare. If I’m wrong then ... well ... I’m just a dummy.

 

[MauleSkinner]

Looks like it’s a bad chart.

 

[CerroTorre]

Thanks. I have a difficult time disregarding something in a textbook until I hear some confirmation I’m not misreading something.

 

[MauleSkinner]

If you google “Koch chart”, you’ll find some that are correct for comparison.

this might also be a good opportunity for you to figure out how to submit errata to the FAA.
Pro Tip: don’t expect any kind of acknowledgment that they even received it.

 

[CerroTorre]

If you google “Koch chart”, you’ll find some that are correct for comparison.

this might also be a good opportunity for you to figure out how to submit errata to the FAA.
Pro Tip: don’t expect any kind of acknowledgment that they even received it.

yeah, not a bad idea.

Although, I wouldnt ever use a chart in a textbook for actual flight planning. It’s arguably just confusing for poor saps like me that are unable to ignore something like this.

 

[Hang 4]

Is anal-retentivity supposed to be hyphenated?

 

[CerroTorre]

hahaha! Well now we’ve all got something else to be analretentive about...