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Hi all, I'm hoping someone can help me witha small problem with FS9.1.  I've been using the prog for about 6 months and am now flying (and landing) lear jets and thinking about moving up to bigger jets.  I find that whatever I fly the airspeed is restricted to 335 knots (beyond that I get an overspeed alarm), now I know they go faster than that IRL but I don't know how to make them do what they are supposed to, speedwise.

Any help would be appreciated.

BTW, fantastic site, glad I found it!

Welcome to SimV!! (You'll like it here! )

Hello friend, I think you're wrong. They dont go much faster  than that in real life.

First of all, you know that at higher altitude you can go faster and burn less fuel right?  :)

A typical speed for a 737 at cruise level at high speed would be 320 knots. Of course, thats the IAS, the ground speed will be higher than that.

When FS says overspeed, you're probably actually going overspeed. Maybe the ground material and lessons in FS would help, unless someone else cares to explain further the meaning of IAS, true airspeed and ground speed.  :)

Cheers and hope I somewhat helped!
Alpha

Hi dubaibilly & welcome to SimV,

The 'problem' you are experiencing with the overspeed alarm going off at 335 in the Learjet is correct.

The problem you have is that you are looking at the speed in KIAS (Knots Indicated Airspeed) - basically, this is the rate of speed that 'air' is hitting your plane at. The max operating speed for a Learjet in KIAS is 335.

However, the higher you fly the faster you will be going because the air is thinner (Even though your KIAS will still be reading 335 - your groundspeed & Mach will be higher).

Above 15,000ft you will need to look at your speed measured in Mach & not KIAS (The blue numbers beneath where you are reading your airspeed is the Mach indicator - it will say something like M 0.55)

How fast you can fly will be directly linked to how high (up to a point) you are flying.

The readings below were taken in clear weather (29.92 inches of mercury on the altimeter) - they will show you the differences in speed compared to KIAS, relative to the altitude I was flying at:

8000ft at 335KIAS = Mach speed of 0.55 (Groundspeed of 359kn)

25,000ft at 335KIAS = Mach speed of 0.76 (Groundspeed of 460kn)

I hope this has helped you a bit, just remember KIAS isn't the only way to measure speed & is really only a useful measure of speed at low altitudes (Although you will have to take into account the direction & speed of the wind).

There was a really good discussion on it HERE that might prove helpful.

Cheers,

TSC.

Many thanks to both of you - guess I've still got a lot to learn!  ::)