A320 FMS altitude constraint in white
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A320 FMS altitude constraint in white
Question for those in the know. What does a white altitude constraint mean in the MCDU? I entered an altitude and upon inserting it, it was green, with a purple asterisk. So far so good. When I changed the altitude to a higher one, the asterisk remained purple, but the altitude was white. We also go the -TOO STEEP PATH- right below the line with the constraints.
Couldn't find it anywhere. Does anyone have an answer with a reference? Thanks
Couldn't find it anywhere. Does anyone have an answer with a reference? Thanks
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Honeywell or Thales?
Question for those in the know. What does a white altitude constraint mean in the MCDU? I entered an altitude and upon inserting it, it was green, with a purple asterisk. So far so good. When I changed the altitude to a higher one, the asterisk remained purple, but the altitude was white. We also go the -TOO STEEP PATH- right below the line with the constraints.
Couldn't find it anywhere. Does anyone have an answer with a reference? Thanks
Couldn't find it anywhere. Does anyone have an answer with a reference? Thanks
9E Alum?
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Was this on the approach? Going white possibly means the FM cannot work out the descent profile which is why you had a too steep path as it cannot work it out from the without knowing the a/c speed. Sometimes setting Vapp at the FAF removes the too steep path, as the FM needed to know what speed at that constraint.
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Question for those in the know. What does a white altitude constraint mean in the MCDU? I entered an altitude and upon inserting it, it was green, with a purple asterisk. So far so good. When I changed the altitude to a higher one, the asterisk remained purple, but the altitude was white. We also go the -TOO STEEP PATH- right below the line with the constraints.
Couldn't find it anywhere. Does anyone have an answer with a reference? Thanks
Couldn't find it anywhere. Does anyone have an answer with a reference? Thanks
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Was this on the approach? Going white possibly means the FM cannot work out the descent profile which is why you had a too steep path as it cannot work it out from the without knowing the a/c speed. Sometimes setting Vapp at the FAF removes the too steep path, as the FM needed to know what speed at that constraint.
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The circle around the constraint on the ND was purple. That was normal. I'm talking about the digits on the MCDU itself being white. We were in the cruise phase, well before top of descent.
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It made the constraint fine. We fly that STAR every day, and like I said it was the only constraint outside of the approach, so there was nothing preventing it from making it.
Only half a speed-brake
Which FMS - at least the supplier, if not the version?
Which constraint, hard alt, or alt+ ?
Either way you have created a vertical discontinuity, the FMS believed it is impossible to rejoin the calculated path due to your CSRT being too high. As a consequence, the last ALT prediction before the discontinuity, the altitude of the constraint itself, was displayed in white instead of the traditional green colour. <---- is that it?
Which constraint, hard alt, or alt+ ?
Either way you have created a vertical discontinuity, the FMS believed it is impossible to rejoin the calculated path due to your CSRT being too high. As a consequence, the last ALT prediction before the discontinuity, the altitude of the constraint itself, was displayed in white instead of the traditional green colour. <---- is that it?
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