Autopilot

[SEWER RAT]

I have my autopilot MCQ paper next month any tricky ones anybody knows about?

And also do any of you do your own de-icing? we do up at sunny LBA and in is a pain in the whatnots.
Thanks and happy new year!!

[WenWe]

Our deicing is done by the same guys who:
>change seat covers,pillows,blankets & the crew doc's bag.
>fix any seats that we have'nt the time for.
>Disinfest the cabin when there's bugs about.
I don't just mean the same company, but the same handfull of blokes.

[SEWER RAT]

So I take it from that reply that not many Licensed Engineers do their own de-icing then.

[CONES R US]

Used to at Belfast City for JEA, but not now.
Oh what fun we had swinging about in a prehistoric jalopy trying our best not to smack into a 146. Real glad I don't have to do it anymore.
sorry, can't help with the autopilot questions. Palletts book is good - also gen up on theory of flight.
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NO FAULT FOUND

[This message has been edited by CONES R US (edited 02 January 2001).]

[reracker]

Don't do de-iceing hangar has got some roof tiles left !!!

Let me have an email address and I should be able to help.

[Jedi Knight]

Leave your email address on this forum and I will try to send you some.
Just sat it so the questions are current.

[Lu Zuckerman]

To: Sewer Rat

Hope this helps.

The The Auto Pilot / Inertial Guidance System.
.

The aircraft knows where it is at all times. It knows this because it
knows where it isn't. By subtracting where it is from where it isn't, or
where it isn't from where it is (whichever is the greater), it obtains a
difference, or deviation.

The Inertial Guidance System uses deviations to generate error signal
commands which instruct the aircraft to move from a position where it is
to a position where it isn't, arriving at a position where it wasn't, or
now is. Consequently, the position where it is, is now the position where
it wasn't; thus, it follows logically that the position where it was is
the position where it isn't.

In the event that the position where the aircraft now is, is not the
position where it wasn't, the Inertial Guidance System has acquired a
variation. Variations are caused by external factors, the discussions of
which are beyond the scope of this report.

A variation is the difference between where the aircraft is and where the
aircraft wasn't. If the variation is considered to be a factor of
significant magnitude, a correction may be applied by the use of the
autopilot system. However, use of this correction requires that the
aircraft now knows where it was because the variation has modified some of
the information which the aircraft has, so it is sure where it isn't.

Nevertheless, the aircraft is sure where it isn't (within reason) and it
knows where it was. It now subtracts where it should be from where it
isn't, where it ought to be from where it wasn't (or vice versa) and
integrates the difference with the product of where it shouldn't be and
where it was; thus obtaining the difference between its deviation and its
variation, which is variable constant called "error".




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The Cat

[SEWER RAT]

Re-racker & Jedi Knight my e-mail address is [email protected].
I have a load of questions from Oxford but would appreciate any particularly nasty ones they are chucking in lately.

Thanks Zuckerman i'll try and memorise that for my oral!!!

[Blacksheep]

Lu,

That sums it up nicely but the aircraft doesnt "always" know where it isn't! Don't forget that sometimes the aircraft is powered down. The inertial system then only knows where it calculated that it wasn't at the time it was shut down, if you fool it by moving it from where it knew it wasn't to somewhere else where it wasn't while it is powered down, then the system is confused when it is powered up again. It can easily work out how far North or South it isn't without human intervention, by calculating the rotational rate of the earth, this being its own rotational rate providing it isn't still moving from where it wasn't to somewhere else where it wasn't at the time it is powered back up again. In the latter case it is impossible for the system to calculate where it isn't, wasn't or won't be in the future and it is then in danger of gyroscopic topple or meltdown (depending on the age of the system or technology in use.) Fortunately a human being is usually on hand to assist it with working out how far East or West it didn't move while it wasn't turned on, which is the reason why both Navigational Instrument System Technicians and Flying Machine Operators have to study the subject.

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Through difficulties to the cinema