EUroute NOTAM Center

EUroute NOTAM Center Implementation Guide

This document is intended for VACCs preparing to implement EUroute NOTAM Center and to other software developers interested in using NOTAMs in their own applications.

1. Brief introduction to NOTAMs

The raw (source, real-life) NOTAM looks for example like this:

A3792/05 NOTAMN Q) EPWW/QWPLW/IV/NBO/AW/000/140/5005N01947E050 A) EPKK B) 0506111230 C) 0506111530 E) MIL PJE WILL TAKE PLACE AT AD EPKP (PSN: 500523N 0201206E), 27 KM EAST FM THR25 OF AD EPKK. F) GND G) FL140

This NOTAM tells us that there will be a military (MIL) parachute jumping exercise (PJE) at airport EPKP, which is 27 kilometers east from threshold runway 25 or airport EPKK. The exercise will take place on 11th of June 2005 (field B) from 12:30 UTC to 15:30 UTC (field C). Every NOTAM has a number (A3792/05 in this example) and a type (NOTAMN - new message). Flights between GND (field F) and FL140 (field G) will be affected. The fields E, F and G contain the human-oriented content, while fields Q, A, B and C specify details that could be potentially understood by computers.

There are two special flags that might appear in field C. "EST" means that duration of the disturbance is only estimated, and this NOTAM will be later cancelled with subsequent message. "PERM" means the duration is unlimited - in such case no date is given (field C contains only "PERM").

In addition to NOTAMN messages, there are two other types. NOTAMR (replacement) is sent out to update previously sent message. For example, if the PJE (parachute jumping) was to be postponed by a few hours, a NOTAMR would be sent out with new C field content. NOTAMC (cancellation) is sent out to indicate that the previous message is no longer valid. NOTAMC could be issued for example if the exercise was cancelled due to bad weather. NOTAMCs are sent out also if the original NOTAM was only estimated in duration ("EST" flag in field C).

2. EUroute NOTAM Center operation

EUroute NOTAM Center (also called EU-NC in this document) is a database of NOTAMs for VATSIM virtual airspace. It collects NOTAMs from VACCs and distributes them to interested parties.

EU-NC does not (and most likely will not) have it's own website where pilots could find NOTAMs for any part of the world. Instead, we help VACCs enrich their websites by giving them access to NOTAM database. We also give pilots a way to fetch NOTAMs directly from EUroute.

The direct access route is also available for automated systems, such as flight planning tools, virtual airline websites, etc. EU-NC follows closely the real life structure of NOTAMs to enable high end third party applications to automatically process the output data.

3. The supply chain

To simplify the process of following real-life changes in virtual airspace, EU-NC uses a real life source of NOTAMs to provide VACC operations officers with up-to-date information. Later, the real life NOTAMs can be checked, edited and published on VATSIM if applicable.

The following picture shows the principle of NOTAM supply chain:

The steps are:

The real life NOTAMs are fetched into the system.
Filtering is applied, first to remove NOTAMs for airports that are not on our list (if you request NOTAMs for a FIR, you also get information for some smaller airports - we discard them); then filters are applied to remove NOTAMs based on keywords. See below for more info on filtering.
VACC staff get an email with list of new NOTAMs that were fetched and not filtered out. Using the administration console, they review NOTAM list and choose what to publish ("Copy to VATSIM") and what to discard ("Do not copy").
Finally, VACC can add their own custom NOTAMs that bypass the above chain.

The filtering process is meant to simplify the life of VACC staff and not bring their attention to NOTAMs that are completely useless. Some examples of filters are:

all AGXX messages with "RUNWAY FRICTION CALIBRATION" in the content,
all OBCE (Obstacle Erected) messages,
all FAXX messages with "THE AERODROME CHARGES RATES" in the content,
all messages about "FIREWORKS SHOW" or "BIRD MIGRATION",
all WPLW (parachute jumping will take place) messages,
and many others (there are over 70 filters at the moment).

The VACC staff won't even see messages that were filtered out. All the messages that pass by filtering will be brought to their attention, so that staff can review them and make decisions.

Also, please note that the NOTAM notification by e-mail is only meant for VACC operation officers, not for the general public. The general public will only see the messages that were manually approved. There is no plan for fully automatic copying messages to VATSIM. After the supply chain process is completed, NOTAM will go through a distribution process, where interested parties will receive this information.

4. The distribution of NOTAMs

All NOTAMs approved by VACC staff are published in a common database. There are multiple ways of accessing this database, and thus multiple ways in which the message content can reach the pilots and controllers who might be interested. The following picture shows available means of access:

The following interfaces are available:

RSS is a way to deliver information in a standard way, used by major portals and widely supported by software vendors.
The RSS feed can be displayed on user's desktop, web browser or e-mail client without him having to visit any website. What is important is that data is taken from server automatically and displayed if there's anything new. The pilot does not have to remember about visiting the site. For more information on RSS, see chapter 6.
VACC website can publish NOTAM information in three ways:
- the EUroute NOTAM Center display applet, which easily integrates with their website and does not require any programming skills (see chapter 7 for more information on this)
- using RSS - if they have portal software that supports it, less than 5 minutes are needed to add NOTAM view to website,
- by fetching information in XML format and displaying using custom software (see chapter 5 for more info on XML).
Flight planning tools, such as EUroute Flight Plan Database or Euro-book, can fetch NOTAMs via XML to present them to pilots. This way, planning tools can find NOTAMs that apply to certain route of flight and show only the useful ones.

More information on interfaces is presented in subsequent chapters.

5. XML export of database content

All parties interested can request a dump of all NOTAMs in the database to feed through their own systems. The dump is available in XML format and contains the complete set of fields that a NOTAM message contains, but limited to virtual airspace NOTAMs either currently published, or going live in the future.

The XML dump is divided into so called sites. A "site" is a EU-NC user responsible for an area of airspace - one or more FIRs. Typically, a site would equal to one VACC, however VACCs may decide to split their operations further into separate FIRs.

A site always has a code ("pl"), name ("Polish VACC"), one or more FIRs assigned to it ("EPWW") and contact people who are responsible for maintaining it. For each site, there is a set of NOTAMs that apply to it. Each NOTAM can be uniquely identified by either it's id (a 10-digit number), or by combined ident (i.e. "A3279/05") and FIR ("EPWW" - first part of the Q field).

The up-to-date XML file can be downloaded from http://notams.euroutepro.com/notams.xml. Please note that the URL might change after the beta phase is completed. The file will be generated once a day between 0000 and 0400 UTC. Thus it does not make sense to download it more frequently than once a day. Please avoid downloading exactly at 0400 UTC to avoid congestions. The XML dump might grow in size to hundreds of kilobytes and we're not prepared to handle every VATSIM user downloading it every 10 minutes. If you want to create a software tool that will download the full XML file on behalf of each end user, please consider setting up your own mirror.

The following is a very simple example of the notams.xml file, showing only one site (Spain vACC) and only one NOTAM (A0001/05).

      <opt>
      <general last_update="2005-06-11 10:20:01"
      version="1.0" />
      <sites name="Spain vACC" id="es">
        <fir>LECM</fir>
      </sites>
      <notams name="es">
        <notam id="0000000051" A="LEMD"
        B="2005-05-11 00:00:00" C="" C_flag="PERM"
        D="" E="FORBIDDEN OPERATIONS TO VFR FLIGHTS"
        F="" G="" Q="LECM/QFALV/V/N/A/000/999/4027N-03-32W050"
        ident="A0001/05" type="N" replaces=""
        url="http://notams.euroutepro.com/show.php?id=0000000051"
        />
      </notams>
      </opt>

The order of sections and parameters within one section might change, as usually in XML. If there are any parameters that your application does not recognize, they should be silently ignored. The last_update defines the date when file was produced, in UTC.

The <sites> tag shows a list of all sites. For each site, there's a list of FIRs for that site. Please note that there could be potentially multiple FIRs in one site.

The <notams> section shows all virtual aviation NOTAMs for a given site. For each NOTAM, there's one <notam> entry. Fields should be self-explanatory, except for:

type could be N (new), R (replacement) or C (cancellation)
for type R and C, the field replaces specifies the ident of the NOTAM that was either cancelled or replaced. Please note that the original NOTAM will no longer be available in the XML dump if current date is greater than the B field (cancellation or replacement is already in force).
the url field shows a link to EUroute NOTAM Center page showing in details the content of this NOTAM.
fields with empty values (i.e. C="") are shown as empty string.

If you have any questions regarding the XML format, please contact us at mrok@mrok.com.

6. RSS feeds

RSS feed is a way of distributing information directly to end users. An RSS client will fetch information on regular basis and pop-up if anything new is found. EUroute NOTAM Center uses RSS feeds to inform pilots and controllers about new NOTAMs for their FIRs. See the following screenshot for an example of how RSS pop-ups look like:

To get NOTAMs into your favourite RSS reader, use the following link:

http://notams.euroutepro.com/rss/site_pl.rdf
(note - replace the "pl" with the site you'd like to have NOTAMs for)

If you don't have an RSS application yet, we recommend the free RssReader. Just like in case of XML files, the RSS files are updated daily. There is no point in downloading them every 10 minutes :). To reduce the bandwidth consumption, we only publish current NOTAMs and ones that will go live within next 48 hours. Unlike with XML dump, there is no "global" information file - only the requested sites will be shown.

7. NOTAM display applet

The easiest way to add NOTAM information to your website is to use the web display applet. Here's an example code to paste into your page:

<iframe width=350 height=90 src='http://notams.euroutepro.com/applet.php?notam_site=se&rows=5&chars=22 &icao=EK&show_icao=1&show_from=1&show_to=1&show_ident=0&header=1' scrolling=no frameborder=0> </iframe>

(please note it should be all in one line)

And here's how it looks:

For more information on the display applet and examples, click here.

Contact information

The EUroute NOTAM Center has been designed and programmed by Michał Rok. The system is available free of charge to VATSIM-related organizations.

Page last updated on 27.06.2005.
(c)2005 by Michał Rok