Odd NOTAM lat/long

[robdesbois]

Hi all,
Just checking NOTAMs today and found the following:
Q) EGTT/QWBLW/IV/M/W/000/045/5155N00157W002 FROM: 08/07/19 08:00 TO: 08/07/19 18:30
E) AIR DISPLAY/AEROBATICS CONTEST. EVENT WI 2NM 5210N 00009W (LITTLE
GRANSDEN AD, CAMBS). AUS 08-07-0024/AS2. LOWER: SFC
UPPER: 4300FT AMSL

I'm confused - the NOTAM coded lat/long is somewhere in the Cotswolds nowhere near the event as described in the text.
Why is this? :confused:
--rob

[jxk]

Try Google Earth with 52 10N 000 09W it puts it right over Little Gransden.:O

[bookworm]

I suspect it's the obvious reason -- human input error. I've found half a dozen NOTAMs all coded with those coordinates:

(H1751/08 NOTAMN
Q)EGTT/QROXX/IV/NBO/W/000/025/5155N00157W002
A)EGTT B)0806230700 C)0807040300
D)23-28 30 0700-1800, 01 1200-2300, 03 1600-2359, 04 0000-0300
E)PILOTS ARE REQUESTED TO AVOID OVERFLYING.
FILMING WI 2NM RAD LOCATION 5356N 00126W
(STOCKELD PARK, NR WETHERBY, W YORKS). AUS 08-06-0500/1877/AS2.
F)SFC G)2200FT AMSL)

(H2469/08 NOTAMN
Q)EGTT/QWBLW/IV/M/W/000/045/5155N00157W002
A)EGTT B)0807190800 C)0807191830
E)AIR DISPLAY/AEROBATICS CONTEST. EVENT WI 2NM 5210N 00009W (LITTLE
GRANSDEN AD, CAMBS). AUS 08-07-0024/AS2.
F)SFC G)4300FT AMSL)

(H2495/08 NOTAMN
Q)EGTT/QWALW/IV/M/W/000/999/5155N00157W002
A)EGTT B)0807171900 C)0807192000
D)1900-2000
E)AIR DISPLAY/AEROBATICS (SPITFIRE ACFT). EVENT WI 2NM 5021N 00408W
(THE CITADEL, PLYMOUTH, DEVON). AUS 08-07-0438/AS2.
F) SFC G) 3000FT AMSL)
F)SFC G)3000FT AMSL)

(H2546/08 NOTAMN
Q)EGTT/QWGLW/IV/M/W/000/025/5155N00157W002
A)EGTT B)0807111500 C)0808292359
D)FRI 1400-SS PLUS15
E)GLIDING. ACTIVITY WI 2NM RADIUS 5201N 00018W (RAF HENLOW AD,
BEDFORDSHIRE) SITE OPERATING OUTSIDE PUBLISHED HR. AUS 08-07-0576/AS5
F)SFC G)2200FT AMSL)

(H2489/08 NOTAMN
Q)EGTT/QWALW/IV/M/W/000/025/5155N00157W002
A)EGTT B)0807121500 C)0807121630
E)AIR DISPLAY/AEROBATICS (SPITFIRE ACFT). EVENT WI 2NM 5142N 00001E
(AIMES GREEN, ESSEX). AUS 08-07-0380/AS2.
F)SFC G)2400FT AMSL)

(H2604/08 NOTAMN
Q)EGTT/QWGLW/IV/M/W/000/025/5155N00157W002
A)EGTT B)0807190800 C)0807262359
D)19-26 0800-SS PLUS15
E)GLIDING. ACTIVITY WI 2NM RAD 5141N 00118W (ABINGDON GS, OXON).
SITE OPERATING OUTSIDE PUBLISHED HOURS.
AUS 08-07-0626/AS2.
F)SFC G)2300FT AMSL)

I'll drop a note to AIS.

[Mike Cross]

Who in turn will drop one to CAA/DAP/AUS whose fingerprints are on them all.:uhoh:
(for those who didn't spot it the lat/long in the Q Line doesn't match that in the E Line. Since the Q Line is used to select which ones appear in your brief this is a bit of a boo-boo.)

[WorkingHard]

And if that "boo boo" was the cause of a Red Arrows display infringement who would be prosecuted by the CAA?

[bookworm]

Who in turn will drop one to CAA/DAP/AUS whose fingerprints are on them all.

Just received confirmation of that. I don't know how long AUS will take to remedy this. But well spotted, robdesbois!

[Whirlygig]

Who in turn will drop one to CAA/DAP/AUS whose fingerprints are on them all
Someone whose last location was Charlton Abbotts, just North-East of Cheltenham!!

Cheers

Whirls

[robdesbois]

Thanks all for the responses.

That was only 1 of 2 that day with different Q- and E-line positions...confusing but good to know to look out for it now. Perhaps the NOTAMs also need a disclaimer 'not to be used for operational purposes' :}

--rob

[Mike Cross]

Hi Rob

I've just spoken with David Grove of CAA/DAP/AUS who were responsible for issuing these. He's been in touch with AIS and they believe they have run the problem to ground.

It looks as though there is a problem in the format of the data being sent out by AUS resulting in the Lat/Long in the Q line being defaulted to the centre of the FIR.

I'll try and get some more info.

[robdesbois]

Thanks Mike :)

[bookworm]

It looks as though there is a problem in the format of the data being sent out by AUS resulting in the Lat/Long in the Q line being defaulted to the centre of the FIR.

The villagers of Charlton Abbotts must be delighted to learn that even though their village is not the centre of the known universe, it is at least the centre of the London FIR. ;)

[dont overfil]

That might not be good news if the Vogons pick up on that.
DO.

[Mike Cross]

A bit more info from UK AIS's QA person.

The NOTAM are originated by AUS and sent in as NOTAM Proposals over the AFTN. This is exactly the same method that would be used by any ATC unit to propose the issue of a NOTAM.

AUS have standard templates they use, which have meant that the Proposal SHOULD come out looking very much like the finished NOTAM and require no alteration by AIS staff before it is put into the EAD database. It's been working for years like that with no problems.

The data format uses delimiters to separate the fields. A lot of you will be familiar for example with the csv (Comma Separated Values) format where each line of data contains a complete record with fields separated by commas and text enclosed in quotes. (this means you can have commas in the "the text, like this" without the comma being seen as a field separator).

In the ICAO NOTAM format the lines have a right bracket after the line identifier, so the Q line starts Q) and the E line starts E). The individual items in the Q line are separated by / characters and there ought to be 7 of them in total as their are 8 fields in the Q line.

If any of them are missed out or an extra one finds its way in then the data ends up in the wrong fields.

What's happened is that the templates which worked OK in the old system (ADIMS) are not working OK with EAD so they are being modified to fix the problem. In an ideal world the error should have been picked up by the AIS staff but this type of error can be very difficult for a human to spot when they're working with code like this rather than normal text. Top marks to the eagle-eyed robdesbois for picking it up.

In the short term AUS are updating the templates and AIS (confusing innit) are taking extra care in checking. In the longer term the data validation process needs attention so that errors like this are picked up automatically and flagged up by the computer. I'll be passing this on to NATS IT for attention. (They already have other suggestions from me regarding data validation)

For those not aware, I represent AOPA UK on NOTAM matters.

Mike

[bookworm]

In an ideal world the error should have been picked up by the AIS staff but this type of error can be very difficult for a human to spot when they're working with code like this rather than normal text.

Gosh, I wonder if a graphical display might help them there?

[Mike Cross]

Oooh you tease!

Well it rather depends on whose graphical display you went for doesn't it? If it's one that interprets the E Line to try and find where it is then everything would look fine and dandy whereas if it was one interpreting the Q Line they might spot an awful lot of 4nm diameter cicles over Charlton Abbots. To get the answer you'd have to interpret both and see if they coincided.

A validity check that picked up the geographical centre and radius of influence of the Q line and checked that any co-ordinates in the E line fell within the relevant circle would PROB90 be more reliable.

Mike

[Mike Cross]

Someone else has spotted this one

Q) EGTT/QRTCA/IV/BO/W/000/085/5048N00107W006
FROM: 08/07/25 15:55 TO: 08/07/25 16:33
E) RESTRICTED AREA (TEMPORARY) AT PORTSMOUTH FOR A RED ARROWS DISPLAY
WI 6NM RADIUS 504821N 0010641W AREA ESTABLISHED UNDER ARTICLE 96 OF
THE ANO 2005 (MIL ACFT SHOULD COMPLY WITH JSP552.201.135.9).
AIC 31/2008 (MAUVE 256) DATED 24 APRIL 08 REFERS. AUS 08-07-0048/AS1
LOWER: SFC
UPPER: 8100FT AMSL

so what's the upper limit? FL085 as in the Q line or 8100 feet as in the G Line?

Annex 15 says

6) and 7) LOWER/UPPER
LOWER and UPPER limits shall always be filled and shall only be expressed in flight levels (FL). In the case of navigation warnings and airspace restrictions, values entered shall be consistent with those provided under Items F) and G).
If the subject does not contain specific height information, insert “000” for LOWER and “999” for UPPER as default values.

9. Items F) and G)
These items are normally applicable to navigation warnings or airspace restrictions and are usually part of the PIB entry. Insert both lower and upper height limits of activities or restrictions, clearly indicating reference datum and units of measurement.

I suppose there is some sort of logic at work here as there's no such thing as FL081 so rounding it up to the next higher FL makes sense.

[dublinpilot]

Ah but there is a FL081!

It might not be useable under IFR, and may not be recommonded under VFR, but it does exist! Set your altimiter subscale to 1013, and climb/desend until your altimiter reads 8100, and you're at FL081.