737NG Nav system
 

Hi,
so here's a post which is probably going to receive a few sarcastic answers but I'm struggling to make sense of this.

The following is a question supposedly asked during an interview for Ryanair:
"What type of navigation system is used on the 737NG?"

I'm not really even sure where to start with this question. But so far this is what I've come up with, and if any of this is incorrect I would greatly appreciate being put straight.

ALL 737s (NG and CLassic) have INS. Exact coordinates are entered into the FMS on stand to give the aircrafts 'start-point'. In flight the IRS measures data regarding attitude, speed, heading, acceleration. This data is fed into the FMC which delivers navigation information to the CDUs.

However the NGs use GPS as the primary source of navigation which is more accurate but availability not always guaranteed since it uses military satellites.

now my questions:
1. INS is a required backup system for GPS on the 737?
2. Do the INS and GPS systems use the same CDUs to display nav guidance?
3. Was the initial question a lot more simple than I am making it, by which I mean does the nav system on the 737 simply have a 'brand name' i.e. G1000, Avidyne?

I know this post is a bit of a mishmash and a struggle to read but any pointers would really be appreciated.

They have IRSs not INSs

Very simplified: you have IRS, GPS and then the conventional VHF/HF-systems all "reporting" to the FMC that tries to make out where the airplane is, displaying it on a map on the EFIS.

You also have the conventional presentation displayed via the EFIS or on the standby instrument, such as ILS, VOR, ADF.

The "ADIRU" collects information from the static/dynamic ports and the IRS to supply Heading, altitude, V/S, airspeed

Thanks a lot, makes much more sense

cheers

4) The cheapest possible?

I'll be serious. This is what Boeing says:
So since IRS and GPS are subcomponents of the FMS, I would say the answer is: FMS

Was that a question from a Flight Simulator X simmer?

So far, nobody has mentioned "looking out of the big window in front".

Or is that no longer/not yet EASA approved? :)

Heavens, Barking - what ARE you suggesting?:)

"Heavens, Barking - what ARE you suggesting?"

Hi BOAC, only a little common sense, fact, logic & reasoning, but as we all know, there is a disconnect between these approaches and modern aviation!

However, I'm sure Ryrs flight management would encourage the method if it shortened flight times, saved fuel and reduced the risk of inadvertent ground contact?! Note the order in which these are listed!

What say you, M O'L??!! :)

Dunno, doesn't seem to be a particular EASA problems given the recent excursions to unplanned landing fields in other regions of the world, including the almighty us of a.

Visual approaches of course do fulfill the list of requirements, don't know about ryr, but other carriers still so encourage their pilots to fly them, even if they are MPL cadets. Not a problem given proper training.