11  Flight plans and trajectories

EUROCONTROL’s Network Manager has devised different flight trajectories formats in order to store and exchange information with the aviation community. Trajectories are recorded as either a sequence of 4D positions (3D plus timestamp) or like a sequence of 4D segments.

In the following sections we will cover the most known formats: M1 (& M2) & M3, ALL_FT+ and SO6.

They are a mix of flight information (ADEP, ADES, callsign, …) and trajectory (4D position, ground speed, …).

11.1 Model 1 (M1 or FTFM)

The flight trajectory known as Model 1, M1 or Filed Tactical Flight Model (FTFM) is a mathematical model containing a point and airspace volume profile created in ETFMS for a flight. This trajectory is first created when Flight Plan (FPL) details, and any subsequent changes, are received by the Network Operations of EUROCONTROL’s Network Manager¹.

The M1 is a translation of a FPL (especially Field 15) to a point profile, i.e. a sequence of 4D positions (timestamp + longitude, latitude, altitude) plus relevant penetrated airspace ID’s, calculated taking into account the aircraft type performance (via BADA) and the environment restrictions as published in the Route Availability Document (RAD).

Note

TODO

1. add CSV file with sample M1 data in data/ folder
2. Add small sample of data frame for M1
3. Plot M1

11.2 Model 2 (M2 or RTFM)

An updated version of the M1 when the flight is regulated (i.e. delayed.) This trajectory could be more than a shift in time because of the impact of possibly closed areas or route segments in the new time window of the flight.

11.3 Model 3 (M3 or CTFM)

The flight trajectory known as Model 3, M3 or Current Tactical Flight Model (CTFM) is an updated version of the M1 model (or eventually M2) where the point/airspace profile is recalculated taking into account surveillance data (Correlated Position Reports [CPR]² or more recently ADS-B position reports) when these show a significant deviation from M1 (or M2.) The deviation considered is of 1 min in time, more than 400 feet in en-route phase, more than 1000 feet in climb/descent phase or more than 10 NM laterally, see 14.3.1 [1].

Note

TODO

1. add CSV file with sample M3 data in data/ folder
2. Add small sample of data frame for M3
3. Plot M3 and M1/M3 overlapped to show the differences

11.4 SO6

The SO6 format delivers a flight segment sequence from origin to destination.

#	Field	Type	Size	Comment
1	segment identifier	char		first point name “_” last point name
2	origin of flight	char	4	ICAO code
3	destination of flight	char	4	ICAO code
4	aircraft type	char	4
5	time begin segment	num	6	HHMMSS
6	time end segment	num	6	HHMMSS
7	FL begin segment	num	1 to 3
8	FL end segment	num	1 to 3
9	status	char	1	0=climb, 1=descent, 2=cruise
10	call sign	char
11	date begin segment	num	6	YYMMDD
12	date end segment	num	6	YYMMDD
13	lat begin segment	float		decimal minute
14	lon begin segment	float		decimal minute
15	lat end segment	float		decimal minute
16	lon end segment	float		decimal minute
17	flight identifier	num		must be unique
18	sequence	num		start at 1 for every new flight
19	segment length	float		nautical miles
20	segment parity	num		0=NO, 1=ODD, 2=EVEN, 3=ODD_LOW, 4=EVEN_LOW), 5=ODD_HIGH, 6=EVEN_HIGH, 7=General Purpose Red , 8=General Purpose Orange , 9=General Purpose Yellow

The parity decides flight level allocation: Odd levels are FL290,310,330… and Even levels are FL280,300,320 …

11.5 ALL_FT+

ALL_FT+ files are available via DDR2 and typically follow a naming convention like yyyyMMdd.ALL_FT+, i.e. 20231124.ALL_FT+.7z for data covering November 24th 2022.

The content of an ALL_FT+ file is quite massive, at the time of this writing for version 7 contains 207 columns! ALL_FT+ is clearly an internal NM systems archiving format that has been plainly exchanged.

Documentation and metadata is sparse even from the DDR2 manual or NEST help pages.

Note

TODO this part could help?

Data for a trajectory refer typically to a point profile and can include:

• flight ID / flight number / callsign
• sequence number
• timestamp
• position (longitude, latitude, altitude)
• position ID (i.e. published point ID)
• airspace ID
• (ground / vertical) speed

with timestamp and position as a minimum.

11.6 Flight route

Example: N0441F340 FISTO5B FISTO UY156 PERIG UT210 TUDRA/N0426F280 UT158 AMB AMB9W

11.7 DDR2 exp2

The traffic demand file (exp2) can obtained from the EUROCONTROL’s Demand Data Repository (DDR2) for a selected period of time (typically one day) and geographic area (e.g. FABEC). The exp2 includes, for each flight, basic information about the departure time, the origin and destination airports, a unique flight identifier, the callsign, the aircraft ICAO code (e.g. A320) and the requested flight level by the airspace user as submitted in the flight plan.

[1]

S. Niarchakou and J. Simón Selva, “ATFCM Operations Manual,” Network Manager, EUROCONTROL, 21.0, May 2017. [Online]. Available: http://bit.ly/2zvRCSG.

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1. Aircraft Operators (AO) willing to fly IFR flights in the Network Manager (NM) area of responsibility are mandated to file the relevant Flight Plan to the Network Manager. The aim of this centralised management of FPL’s in Europe is linked to one of the NM mandates, i.e. the ability to detect imbalance between demand (willingness to fly by AO’s) and offer (ability to guarantee safety by ATC / airport capacity providing an adequate level of safety). The NM provides the ACC’s/airports to monitor the situation and implement measures to resolve the overload (typically via departure delays or rerouting.)

2. CPRs are received by NM from ACC’s, they consist of surveillance data (callsign longitude, latitude, altitude, timestamp) paired with flight plan info (aircraft type, ICAO 24-bit address)