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View Full Version : How to use INS and IRS system?


firstch
14th Sep 2017, 02:38
Hi everyone

Now I'm study an ATPL course an Im get confuse about navigation system .Can any one give me an explanation of INS and IRS navigation system and also how to use it ?

Thanks you for all coming answer:)

Tu.114
14th Sep 2017, 08:21
This is quite a question...

In a nutshell, such systems measure the accelerations they are exposed to and use those values to deduce changes to their position in space. But trying to briefly explain it on here would not do these systems, their complexity, their inherent errors and the different installations in various aircraft types justice at all.

IŽd suggest you hit the books and obtain a basic understanding of gyros and the effects of accelerations on the same first. Then go on with your course documentation on dead reckoning navigation and finally read the same documentation on the inertial navigation systems. They have several inputs they use for their internal number crunching. Look at the bunch of other accelerations beyond aircraft movement relative to the earth such a system is subject to and how they are eliminated out of the calculations. Then you will also see why and how the IRS is suffering from measuring errors, especially in the long run. Also consider the interaction of the inertial systems with other navigational sources and how they are used to cancel each others inherent weaknesses out.

And, that done, look at the individual type you are operating to see how exactly the systems work there and what the SOPs and abnormal procedures say on their use.

Check Airman
14th Sep 2017, 08:41
How to use it? Select NAV on the control panel then go about your day.

PEI_3721
14th Sep 2017, 10:22
Inertial Reference relates to the motion of the aircraft; the system can detect speed and acceleration. These are outputs for navigation.

Inertial Navigation uses the reference computations in the process of navigation - requires a computer; INS normally have an IRS within the overall system.
Navigation requires positional knowledge - an essential input for navigation and for some systems aligning inertial platforms.
Where am I (where have I been), where do I wish to go. Positional predictions can be made based on acceleration, speed, and direction - where am I actually going.
Navigation control can be achieved by comparing the desired destination with that predicted - what the aircraft is actually doing.

wiggy
14th Sep 2017, 11:06
It is indeed quite a question.

As has been said the easy answer is start the system(s) aligning and then wait for it to go into Nav/select Nav, as appropriate, then off you go.....but TBH I am minded of the Python sketch about "how to play the flute"?

Answer: "Blow in the end and move your fingers up and down"..

I think the OP needs a good book......