attitude indicator and centrifugal force
attitude indicator and centrifugal force
(OP)
I was wondering about the basics of attitude indicators.
My questions are:
How does centrifugal force affect the attitude indicator? When the plane banks, can the indicator tell the difference between centrifugal force and gravity?
What about digital indicators? Can they keep an accurate reading while centrifugal force acts on them?
Can fighter jets' indicators keep an accurate reading while they are banking with multiple g-forces?
Thanks!
mighty
My questions are:
How does centrifugal force affect the attitude indicator? When the plane banks, can the indicator tell the difference between centrifugal force and gravity?
What about digital indicators? Can they keep an accurate reading while centrifugal force acts on them?
Can fighter jets' indicators keep an accurate reading while they are banking with multiple g-forces?
Thanks!
mighty





RE: attitude indicator and centrifugal force
TTFN
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RE: attitude indicator and centrifugal force
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RE: attitude indicator and centrifugal force
As to your question about digital indicators, keep in mind that digital indictators typically draw their inputs from a remote mounted sensor, and thus the narrow answer to your question is that digital indicators are not affected by these forces. However, the complete answer that I suspect you wanted to know is that the remote sensor to which they connect and from which they obtain their data will be subject to those forces.
So if the remote sensor is a rotating mass gyro, the same errors apply, although remote mounted sensors normally have superior error correction capability. That is one of the reasons they are remote mounted...to have the space to include capable error correction circuitry.
If your indicator uses a system as its sensor that instead of rotating mass has accelerometers or magnetometers (usually one or more for each axis - longitudinal, lateral and vertical), the circuitry that processes the combined signals does some thorough error correction before the signal is sent to the indicator for viewing by the pilot.
Hope this helps!
RE: attitude indicator and centrifugal force
however, I'm still not clear on whether there is an attitude indicator that can keep an accurate reading during multiple changes of multiple g-forces, such as a fighter jet may experience in operation.
Also, by digital, I meant is there an attitude indicator that operates without any gyro at all? (like how an iphone knows which way it is facing at all times). With new digital technology, are we beyond the need for gyros to tell us attitude?
Thanks again!
mighty
RE: attitude indicator and centrifugal force
RE: attitude indicator and centrifugal force
RE: attitude indicator and centrifugal force
RE: attitude indicator and centrifugal force
In any case, a fighter's attitude displays are different, in that they are NOT derived from a single sensor; the mission computer has total knowledge of all sensor inputs, including GPS, and can generate synthetic data that represents the aircraft's true heading and attitude regardless of the turn conditions.
INS is simply the processor plus gyros plus accels plus GPS plus other ancillary sensors
TTFN
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RE: attitude indicator and centrifugal force
Thinking of a classical ADI, a horizon and directional gyro, each in a gimbals to allow three axes of rotation. It is quite conceivable and proably not very hard to design the gyro and gimbals such that the CG of the moving assy is always at the intersection of the axes of rotation with necesary precision. As such, linear inertial forces would not cause the gyro to move.
Now Laser ring gyros are something completely different. Look it up.
RE: attitude indicator and centrifugal force
As technology has improved, the undesirable effects of the external applied forces have been greatly improved. Examples of improved gyros are laser ring and solid state. But even with these improvements, mother nature still has an effect an attitude indicators.
Also, gyros are impacted by apparent precession, this is when the gyro alignment relative to the earth changes because of the rotation of the earth. Apparent precession has a large impact on directional gyros and this is corrected by the flux gate correction signal.
Anyway, cheers.
RE: attitude indicator and centrifugal force
mighty