IRS Alignment
Join Date: Jan 2014
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Salute!
Thank you, Rivett a really neat system, and
With a few operating instructions, many requirements and such will be answered for the folks here
I now step off the platform.
Gums sends..
Thank you, Rivett a really neat system, and
With a few operating instructions, many requirements and such will be answered for the folks here
I now step off the platform.
Gums sends..
Join Date: Oct 2003
Location: If this is Tuesday, it must be?
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Interesting that the Honeywell document claims the Laseref VI is installed in the Challenger 605, while the FCOM states the Laseref V. It may be that the production standard was upgraded and the text about realignmnet conditions was changed, but the intro text wasn't. And unless the change was pre-production then there should be text covering both variants.
Ah, well, not the first error i've come across in an aircraft manual.
Ah, well, not the first error i've come across in an aircraft manual.
Cunning Artificer
Join Date: Jun 2001
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We used to do full alignments on the 737 Classic every stop, until the IRS failure rate started climbing, we were then told to fast align (pre RVSM) which seemed to clear the issues. IRS realignment in flight I was always under the impression is impossible... I actually laughed at somebody who thought it could be done... but I guess technology has progressed...
.Salute!
It may surprise you, Flash, but a year or two before you were born we could do an airborne alignment in our SLUF.
Crude level for the "platform" like most AHRS did those days, then use a rough present position to start the alignment ( that provided theoretical Earth rotation data) and then use velocity inputs from our doppler. Find a good reference for a position update 15 or 20 minuites later and walla!
As you assert, technology has progressed, and further and faster than most of us ever imagined.
Gums sends...
It may surprise you, Flash, but a year or two before you were born we could do an airborne alignment in our SLUF.
Crude level for the "platform" like most AHRS did those days, then use a rough present position to start the alignment ( that provided theoretical Earth rotation data) and then use velocity inputs from our doppler. Find a good reference for a position update 15 or 20 minuites later and walla!
As you assert, technology has progressed, and further and faster than most of us ever imagined.
Gums sends...
It may surprise you, Flash, but a year or two before you were born we could do an airborne alignment in our SLUF.
Join Date: Dec 2007
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I think theoretically it's possible but IRS is an independent system and quite old on older aircrafts with simple cpu so just to make it simpler and save cost it's done this way. It will make no sense to depart unaligned anyway because artificial horizont will not work.
Back in the 1960s, gyro IRS systems that were expected to remain precise over longer periods of time could use star spotter systems to provide in-flight calibration. Apollo had a manually operated system on board the command module. And the B-70 design was to incorporate an automated system that would work at high altitudes even in daylight.
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IIRC, the SR-71 had such an astronavigation system installed and fully operational
Quick edit: Indeed it had it. It was the Nordtronics NAS-14.
https://timeandnavigation.si.edu/mul...igation-system
BF
Quick edit: Indeed it had it. It was the Nordtronics NAS-14.
https://timeandnavigation.si.edu/mul...igation-system
BF
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Now it's been stated that the GNSS systems can update the IRS/INS.
But what about DME/DME or VOR/DME, in case the GNSS is being "offset" or is unavailable... or will the system stay on the IRS/INS until an update is commanded, and then use the groundbased stations for updating reference?
Or is the FMS constantly checking IRS/INS versus all other sensors?
Edit: RNAV
But what about DME/DME or VOR/DME, in case the GNSS is being "offset" or is unavailable... or will the system stay on the IRS/INS until an update is commanded, and then use the groundbased stations for updating reference?
Or is the FMS constantly checking IRS/INS versus all other sensors?
Edit: RNAV
