Way back when...
A long time ago, I flew the Lear 23. What a great airplane! And, it was equipped with a well-calibrated A-O-A indicator. Now, there were later modifications by various outfits who did wing mods (among other things), and I flew the 23 with Century mod, the Raisbeck mod, etc., and those outfits put in an even more refined A-O-A system.
Anyway, it got to the point where you really didn't need any airspeed indicator at all. Really, just pitch, thrust, and A-O-A. It worked well for working out flaps on approach, retracting flaps after takeoff, long range cruise, high speed cruise...you name it, the A-O-A indicator worked well. And, now, later, that we're doing the windshear recovery drills...it's a great tool for that, too.
I really don't understand why we do have these neat things in 'big airplanes'....I mean well-calibrated indicators. Maybe Old Smokey can answer this for me.
But, I remember I got to the point where I used the A-O-A indicator for best rate of climb, best angle of climb....if you know what angle is correct for what you want to do...you're spot on target. (And, use the airpseed/MACH indicator as a supporting instrument.)
I guess, to a degree, we use the FPV in a similar manner...but, you have to go through all this mess in the abnormal/emergency checklist...You go to the column that has your approximate weight...then, you cross reference with configuration...get your N1 or EPR target setting, etc., etc.
Maybe someone can tell me why we don't use this technology. Fighter jets have been using this since before time began....
PantLoad