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code0
16th Aug 2012, 16:23
Greetings guys!

This is the ND of Boeing 737-800

http://flightlevel350.tumblr.com/image/29556344615

http://flightlevel350.tumblr.com/image/29556344615

Bottom Arrow:
Could anybody tell me what is RNP and ANP - Required/Actual Navigational Performance exactly? and how it can be used in an approach? or do you use during cruise, etc?

Top Arrow:
what is TRNB 0152.4z ?

many thanks in advance!

Denti
16th Aug 2012, 17:51
Obviously a flightsim question, please mark that next time in the title.

Anyway, RNP is the Required Navigation Performance for the current environment, ANP is the Actual Navigation Performance.

TRNB is the next waypoint and the time the aircraft arrives at that waypoint is 0152.4z.

code0
17th Aug 2012, 12:39
Thanx Denti for the reply and yeah i ll mention that next time!

aterpster
17th Aug 2012, 14:03
Where is TRNB? I can't find it in a worldwide database.

Torque Tonight
17th Aug 2012, 14:18
4 letter identifiers are normally ICAO airport codes, with TR being the prefix for Montserrat. However there doesn't seem to be a TRNB and it would be unusual (but quite possible) to be navigating directly to an airfield reference point. TRNB could be a user created waypoint or may just be random letters to demonstrate elements of the display.

Pub User
17th Aug 2012, 16:46
It could be the older Boeing system of using 'NB' after the name of an NDB. Is there a 'TR' NDB in your database?

FlightPathOBN
17th Aug 2012, 18:17
Check this site. (http://forum.navigraph.com/forum/Default.aspx?g=posts&m=12542) It appears the ARINC coding is incorrect, at UKBB/KPB, the mistake is that the TR NDB is coded as IF, not a TF leg.

Here is a low cost explanation of RNP and ANP....
from 737.org (http://www.b737.org.uk/navigation.htm#Position)

Actual Navigation Performance (ANP) is the FMC's estimate of the quality of its position determination. The FMC is 95% certain the the aircraft's actual position lies within a circle of radius ANP centred on the FMC position. Therefore the lower the ANP, the more confident the FMC is of its position estimate.

Required Navigation Performance (RNP) is the desired limit of navigational accuracy and is specified by the kind of airspace you are in. Eg for BRNAV above FL150, RNP=2.00nm. The RNP may be overwritten by crew.

ACTUAL should always be less than RNP.

c100driver
18th Aug 2012, 03:58
Actual Navigation Performance (ANP) is the FMC's estimate of the quality of its position determination. The FMC is 95% certain the the aircraft's actual position lies within a circle of radius ANP centred on the FMC position. Therefore the lower the ANP, the more confident the FMC is of its position estimate.

To be more correct, you should say the lower the ANP the smaller radii of position uncertainty.

The FMC is neither more or less confident, it is just the size of the uncertainty that changes.

FlightPathOBN
18th Aug 2012, 05:14
In context, I am sure it is fine...

code0
18th Aug 2012, 06:09
Thanks a lot for the information. 737.org helped a lot, so are all replies above!

To tell you bit of extra info about this, I was flying a simulator session from VCBI to VOTR and an ILS approach to RWY 27 @ VOTR. I had to do a Go Around so I made a TOGA and suddenly TRNB 0152.4z appeared in the ND confusing me.

I am studying B1, but trying to get the whole concept of flying so I could understand more things when the aircraft is flying as now I spend more time with the aircraft when it is on ground :)

Thanks to all!

aterpster
18th Aug 2012, 14:15
Pub User:

It could be the older Boeing system of using 'NB' after the name of an NDB. Is there a 'TR' NDB in your database?

Worldwide:

9 TR NDBs, 3 TR VORs.

BOAC
18th Aug 2012, 16:18
It could be the older Boeing system of using 'NB' after the name of an NDB. Is there a 'TR' NDB in your database? - there certainly is if you look at the route page.

Code0 - here is your NDB at VOTR..

http://www.google.co.uk/url?sa=t&rct=j&q=world%20aero%20data%3A%20navaid%20tiruchirappalli%20ndb%20--%20tr&source=web&cd=1&cad=rja&ved=0CEoQFjAA&url=http%3A%2F%2Fworldaerodata.com%2Fwad.cgi%3Fnav%3DTIRUCHI RAPPALLI%26nav_id%3DTR%26nav_type%3D5&ei=J8AvUMr9B9HY0QXY2YHYDA&usg=AFQjCNEDfB7UNEAHRlA0maBP6kcHgDO-uQ

code0
18th Aug 2012, 16:55
@BOAC . . precisely! thanks a trillion for digging up!

BOAC
18th Aug 2012, 17:10
My pleasure - just had to stop this 'wandering around the houses' we have been watching:ugh: Quite how we finished up in UKBB at an IF or Montserrat defeats me. I found at least 6 TR NDBs worldwide.

If you look up VOTR in the India AIP you will see the hold at TR. The g/a off 27 goes right to the TR to hold.

FlightPathOBN
19th Aug 2012, 00:34
The same question was posted on another Sim site...there is a TR NDB there as well, that was coded in the SIM database as an IF not TF leg, and it made sense with the image shown...
thats how! :}

code0
19th Aug 2012, 03:34
Thank you all! and thanks for the time for reading and replying!

Just a small question what is a TR NDB ? and TR VOR? . . . is it a special kind ?

Thanks in advance!

BOAC
19th Aug 2012, 07:12
code0 - if you look at the link I gave you will/?should? clearly see 'TR' is the ident.

I feel this thread should be in 'Spectators Balcony':ugh: We have no idea what level of piloting knowledge your 'B1' licence give you and I feel we are wasting our time here with someone who cannot use a search engine.:mad:

Exactly WHAT is your level of piloting knowledge?

Torque Tonight
19th Aug 2012, 16:52
If ever you were an instructor BOAC, I presume you would have specialised in the 'I can do it so why can't you' instructional technique. Whatever happened to sharing knowledge with encouragement and good grace. If you really feel that as you said, you are wasting your time, perhaps you shouldn't bother answering people's questions at all. Incidentally, that format for an NDB is certainly not common to all Boeing FMCs.

BOAC
19th Aug 2012, 16:58
You mean like up to post #17 when I realised what we were dealing with.? Doh! You would have been chopped.:)

You probably did not notice, either, but the last question was "Just a small question what is a TR NDB ? and TR VOR? . . . is it a special kind ?"

Can you work that out for yourself or do you need help?

Torque Tonight
19th Aug 2012, 17:30
Certainly some people here know less than others, but I don't think any of us know it all, even you ;), so perhaps a little friendly elucidation of information is no bad thing.

Grasscarp
19th Aug 2012, 19:48
A VOR is a VHR omni range bearing navigation aid. It is a large piece of apparatus on the ground and looks a bit like a birthday cake design (with candles!). It is radiating a signal on each of 360 degrees so you can fly towards or away from it with accuracy, especially as they are usually colocated with distance measuring equipment (DME) to give you a bearing and range. An NDB is a relatively cheap piece of equipment and it can be strung from a tower and the line is sending out a signal in all directions, hence non directional beacon. This used to be used on airways as well as at terminals, but has been replaced largely by the more accurate VORs. Now it is still found at airports for locator beacons from which to start an approach, as well as still being used on some airways.

BOAC
20th Aug 2012, 06:49
QUOTE=PPRune If you are a professional pilot or your work involves professional aviation please use this forum for questions. Enthusiasts, please use the 'Spectators Balcony' forum ./QUOTE

grounded27
20th Aug 2012, 07:40
The OP later stated he/she was working on a B1.

"We have no idea what level of piloting knowledge your 'B1' licence give you and I feel we are wasting our time here with someone who cannot use a search engine.http://images.ibsrv.net/ibsrv/res/src:www.pprune.org/get/images/smilies/censored.gif"

This person may be be better suited posting in the eng/tech forum. None the less YOU should be best suited to answer this question being a seasoned pilot. Sir, you wasted only your time in this response.. I might guide him to the tech/engeneer forum for possible information.

Hey this thread kicked me in the short and curlys as today I had a PDIS "lost Vref and predictive info". I am sure it was an awakening for these gents to fly this jet with this loss.

On my end we have no FMS training other than what we gather as a group and share.... PILOT information helps mutch. I for one have learned how to set up an FMS for flight, predictive data came up to 10k.

My point is, the more we get from you, the more we return in share and likewise. In the end you will see there is no high horse.

code0
20th Aug 2012, 07:47
Sigma! Take it easy BOAC, dont get your veins boiled up :) B1 is the Eng lisence NOT the flying. :D

and why I am in the Professional Pilots section is go get my clarifications advised by professional pilots! NOT by sim pilots. You may ignore whatever the posts that feels like a waste! there are a quite a few of "Professional Pilots" that I can get my doubts clarified. :D

But thank you for you earlier posts and links!

And thank you Torque Tonight! thank you Grasscarp! :D

Thanks to all!

Code0

Denti
20th Aug 2012, 08:03
The thread was moved into his forum by some moderator, no fault of the OP. It started in the techlog section which was more appropriate in my opinion.

I just wonder, do the engineering staff have access to the flight crew documentation? Something like the FCOM or OM B vol 3? That would explain most if not all of the original questions. Since I am used to them having that kind of access (its just the normal way of things in "my" company) I wrongly assumed the OP to be a flight simmer, as the questions were typical of the kind of basic stuff asked by simmers.

Lookleft
22nd Aug 2012, 07:57
Maybe the Mods need to create a separate forum for flight sim questions so that what appear to be technical questions from new pilots are actually flight simmers coming to grips with what goes on in a cockpit. Its a bit like asking professional IT people "What's a mouse and how often should I change the paper in its cage?".

FlightPathOBN
22nd Aug 2012, 16:45
LL, BOAC, all...

Concur!

No problem helping out the sim types, after all, procedures are run through a sim when developed, but the answers can certainly be much different than ops.

So yes, there should be a separate section, because a thread can lose the foundation of the original question.
A sim question clearly identified as such...