737ng Nav Data Out Of Date

[citizensun]

if one day you have a nav data out of date problem on the fmc, and cannot be updated ,cause it isn`t in the company base ,no data disk out there.
the aircraft still can be released by the mel.
and during flight in the rvsm airspace, the atc request the crew to excute the offset to the right 5 miles, myquestion is: can the crew comply with the atc`s instructions?
can someone shed some light on me ? very appreciated! :ok::ok:

[grounded27]

While deferred the nav data is still functional, just out of date. I would say yes, and there is a 99.9% chance you are on course. Most updates are airport/terrain changes from what I am told.

[Avenger]

Think about it! if ATC request a 5ml offset, then they can see you, so what's this got to do with the Nav Database, of course you can comply.

[ImbracableCrunk]

I was told that with the NAV database out of date, you could use it for enroute, but not for SID, STAR, and APP. If the MEL says it can be used for enroute NAV, offset should be fine.

[grounded27]

Besides, if it is not an operational restriction of your MEL you operate normal.

[mustafagander]

Are you really CERTAIN that you can operate under the IFR with an expired data base???

Not me pal!!

Think of the subsequent court of enquiry - for the lawyers BMWs all round and for the pilots ??????

[Sciolistes]

Are you really CERTAIN that you can operate under the IFR with an expired data base???
Absolutely for the Classic. MEL says not required as long as the operational procedure to verify the FMC route and monitor approach navaids is complied with.

[BOAC]

.and the NG - typically a 10 day limit. Not sure I'd operate an RNAV approach though!

[mutt]

Are you really CERTAIN that you can operate under the IFR with an expired data base??? Yep, permitted by the FAA Approved Minimum Equipment List.


Mutt

[Sciolistes]

BOAC,
Not sure I'd operate an RNAV approach though!
I agree. With regard to your comment in another thread along the lines of exclaiming does everything need a rule! I suppose the problem is with so many rules, when an obvious one is missing somebody says, "it's legal, what's the problem?"

So yes, interesting that RNAV was omitted, but also departure navaids too.

[MrBernoulli]

Think about it! if ATC request a 5ml offset, then they can see you, so what's this got to do with the Nav Database, of course you can comply.Incorrect! There are a lot of places where a 737NG (or any other aircraft for that matter) could go where there is no radar cover, but you are in comms with an ATC unit!

[Denti]

I guess it depends in what kind of environment you operate. In europe for example the use of RNAV is required above a certain level (FL95 for most countries) and an out of date nav database is not approved for operation in that airspace.

Our 737 MEL has therefore an entry that allows all nav databases to be out of date only if there is no requirement for any RNAV procedure or navigation and of course as long as you have current charts on boards (charts are no longer required in dual FMC installation with EFB installed which may be inoperative as well). If you want to use any kind of RNAV procedures, no matter if enroute, approaches or departures, you need at least one current nav database on board and usable for the crewmember responsible for navigation.

You can allways try to file a non-RNAV flightplan, i had to use that once when our FMC forgot its database completely every time the aircraft was powered down. However that was a purely domestic flight and prior approval by any ATC unit in contact during our flight was necessary. On another occasion where we still had the FMC but the FMC-AP interface was gone we couldn't fly into switzerland as neighbouring country because they would not approve us without PRNAV, the aircraft was AOG until the problem was fixed.

To be honest i have never seen an out of date nav database in airline operation on the 737 so far, with good maintenance procedure and the possibility to pre-store the next database up to 27 days prior the date it becomes active it seems easy to keep them current.

[aterpster]

denti:

Our 737 MEL has therefore an entry that allows all nav databases to be out of date only if there is no requirement for any RNAV procedure or navigation and of course as long as you have current charts on boards (charts are no longer required in dual FMC installation with EFB installed which may be inoperative as well). If you want to use any kind of RNAV procedures, no matter if enroute, approaches or departures, you need at least one current nav database on board and usable for the crewmember responsible for navigation.

You are authorized to fly instrument approach procedures without either paper or electronic (EFB) charts?

To be honest i have never seen an out of date nav database in airline operation on the 737 so far, with good maintenance procedure and the possibility to pre-store the next database up to 27 days prior the date it becomes active it seems easy to keep them current.

Major chart cycles are every 56 days with an interim update cycle, thus a database change every 28 days. It's not possible for database vendors to have a database ready 27 days before its effective date, at least not that I have seen. In my current work I receive a world wide nav database typically 14 to a maximum of 17 days before it becomes effective.

[Denti]

You are authorized to fly instrument approach procedures without either paper or electronic (EFB) charts?

Not on a routine basis, only if both EFB become u/s during a flight and under certain circumstances out of base, however in practical use that is impossible as all weight and balance as well as performance calculation is done on the EFB as well.

Major chart cycles are every 56 days with an interim update cycle, thus a database change every 28 days. It's not possible for database vendors to have a database ready 27 days before its effective date, at least not that I have seen. In my current work I receive a world wide nav database typically 14 to a maximum of 17 days before it becomes effective.

Yup, still more than enough time to distribute it even through a large fleet. Even more possible if you do not need a worldwide database and therefore get your update cycle even earlier.

[Nightrider]

To be honest i have never seen an out of date nav database in airline operation on the 737 so far, with good maintenance procedure and the possibility to pre-store the next database up to 27 days prior the date it becomes active it seems easy to keep them current.


Denti, you are a very lucky guy....there are many out there (including me) who have or still do see this on an often regular basis...

[BOAC]

Including some who have operated for some days with NO database at all due to an eng dept cock-up:=

[Sciolistes]

Did that fairly recently. Just had to create all the waypoints, airports and navaids manually in the temporary nav database. Time consuming and error prone.

[Avenger]

737 Dispatch Deviations Guide
34-36-01-04 Navigation Databases
May be out of currency provided:
a. Current aeronautical charts are used to verify navigation fixes prior to
dispatch.
b. Procedures are established and used to verify status and suitability of
navigation facilities used to define route of flight.
c. Approach navigation radios are manually tuned and identified.

The original question was not about RNAV approachs etc, simply an offset, I still say yes!