On 19 Apr 2002 05:25:24 -0700, Tony Peden <[EMAIL PROTECTED]> wrote in message <1019219125.18988.16.camel@raptor>:
> On Thu, 2002-04-18 at 17:57, John Wojnaroski wrote: > > > > ----- Original Message ----- > > From: John Wojnaroski > > To: [EMAIL PROTECTED] > > Sent: Thursday, April 18, 2002 3:02 PM > > Subject: Airspeeds? > > > > > > Hi, > > > > On the subject of airspeeds: > > > > Indicated Airspeed (IAS) is calculated based on the difference > > between stagnation pressure in the pitot tube and the static > > pressure. formula is square root of 2 x [ stag - static ] / air > > density, if I recall correctly. > > > > now to get to true airspeed (TAS) we pass through a couple of > > "filters" > > > > Calibrated Airspeed (CAS) is IAS corrected for installation and > > position of the sensors which can be somewhat > > complex and it also varies during high AOAs and beta's. > > Variation with alpha and beta is a product of the pitot-static system, > so these errors will be apparent in IAS as well. ... > For a simulator, IAS is impossible to compute in a generic way since > the variation from CAS will be different from airplane to airplane. ... > We do not do installation corrections at all, just give CAS as IAS. > (This is usually what the instrument is trying to show anyway) ..most planes have some info on IAS -> CAS conversion, placarded or in manuals etc, these form workable starting points? ..for magnetic compass manouvering errors: compare it with a gyro in standard rate turns, double rate turns etc, both righthand and lefthand. Video tape the pair. And chances are we want this tape for all magnetic latitudes... ;-) -- ..med vennlig hilsen = with Kind Regards from Arnt... ;-) ...with a number of polar bear hunters in his ancestry... Scenarios always come in sets of three: best case, worst case, and just in case. _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
