JABBARA
18th Sep 2010, 19:51
A 330 Vol 3, 3.04.91 P7 COLD WEATHER procedures:
..IRS alignment ..below -15 C needs 15 minutes
I know how IRS works and why it needs time to align.
As summarized: Alignment needs time to detecet the dipping rate of gyro (even laser gyro) as earth rotates. Near equator needs less time for alignment becuse dipping rate is high due of earth rotation. As closer to poles needs more time becuse of similiar reason. At the end, we know this dipping rate is used by IRS to calculate present lattitude by itself. These all clear.
The question is "how or why cold temperature extends the alignment time of IRS?"
Thank you
Edit reason: editorial
..IRS alignment ..below -15 C needs 15 minutes
I know how IRS works and why it needs time to align.
As summarized: Alignment needs time to detecet the dipping rate of gyro (even laser gyro) as earth rotates. Near equator needs less time for alignment becuse dipping rate is high due of earth rotation. As closer to poles needs more time becuse of similiar reason. At the end, we know this dipping rate is used by IRS to calculate present lattitude by itself. These all clear.
The question is "how or why cold temperature extends the alignment time of IRS?"
Thank you
Edit reason: editorial