How do you read EM diagrams?

I saw some discussions on the Viper’s turn performance and that got me digging through some old manuals I’ve got on my harddrive. I’ve got the “doghouse charts” and was curious about learning how to actually read them, but I’m totally lost in the maze of curved lines and “Ps.” I found a guide on SimHQ, but it was using a WW2 EM diagram that had much less going on. I was wondering if anyone here could help me figure out:

  • How to find sustained turn rate
  • How to find sustained G

I’m still figuring it out, to be honest.

Check out this doc, it does a reasonably good job of outlining the elements of the graph for the T-45.

It goes through rate band, radius band etc. Chapter 1, pages 1-1 to 1-11.

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To find the maximum sustained rate, find the highest degrees per second turn rate associated with 0 feet per second altitude loss.

To find the maximum sustainable G, find the highest G associated with 0 feet per second altitude loss


Would that be the “Ps = 0 FPS” dotted lines on the chart?

Yes, Ps = FPS usually indicates specific excess power expressed as altitude change.

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