Why is IAS supposed to be better

[rodbarker007]

Im having a hard time grasping this speed setting concept and how its better one way or the other , I had a look at wiki Air Speed and it still doesnt explain why its better , what information is IAS giving you that makes it better than TAS .

[Coelian]

It gives you actual speed of your plane.

[Foxtrot39]

Wing rip occure when reaching the limit IAS limit, hence what is said above

[rodbarker007]

Thanks guys .

I found this post on another forum I thought Id put it up for other guys that want to understand this stuff .

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True airspeed gives you your 'true' airspeed yes.

But guess what? Your aircraft doesn't care about your 'True' airspeed. :Ps

When you overspeed the aircraft, when you over extend flaps, when you stall, when you achieve your best rate of climb speeds.... ALL IAS

Why? Because those same diffrences that differ TAS to IAS (Well CAS but IAS will suffice here) also effect your wings, engine and control performance.

So... in game. You can know what speed you could be doing if there was sufficient density around you. Tells you nothing of performance. Suit yourself.

~Take an aircraft to sea level, maneuver as much as you want but pay attention to the speeds you are doing it in TAS and IAS. Go to 20K feet then try the same maneuvers at the same TAS... guess what? You can't do most of them. Now try again with the same IAS as before... you can still do most of them.

Or if you really want the lol's try and do some maneuvers at altitude with a higher TAS speed, then try it again at sea level and see how long you keep your wings.

Before you continue, you should know you are arguing with actual pilots.

Now why these different airspeed exist is for a few reasons. First off; You're aircraft flies off IAS, it performs off IAS and is limited by an IAS. You use that in flight.

CAS, can be interchanged with IAS for some instances for the aircraft with the corrections in primarily instrumentation and position.

TAS? Mostly important for a navigational use, in planning and to some degree in flight but its not often needed to be known in real time.

(If you want to try quoting the wiki page then actually read it lol True airspeed is not used for controlling the aircraft during taxiing, takeoff, climb, descent, approach or landing; for these purposes the Indicated airspeed – IAS or KIAS (knots indicated airspeed) – is used.)


TAS can also be used for a calculation of Mach number provided other factors are also provided.

And wrong again. TAS can't be used for 'flying' as such. Even in commercial airliners at high altitude or even an SR-71 at high alt; they display IAS because they need to know their critical speeds (based upon an IAS speed) and Mach number(Again to know their limitations). TAS is never used for 'flying' the aircraft.

For most light aircraft your IAS is used for navigation at low altitude, TAS only gets used at higher alt/speed.

In game... you're not planning a navigation rout. You have a moving map. I'd be impressed if you are calculating ETA's at high altitude when cruising just off what you see... But the difference between the two isn't that huge to begin with, with the aircraft we have in games... Aside from that the need to know your performance and limitations far out weighs that.