The idea behind FUA
Instead of closing military airspace permanently, FUA lets civil and military users share it in time. The common rules are in Commission Regulation (EC) No 2150/2005, and EUROCONTROL's ERNIP Part 3, the Airspace Management Handbook, describes how states apply them.
For a pilot, the practical effect is simple: many areas on the chart are reserved only when someone needs them, and that is decided and published day by day. If you want to see how NOTAMbriefing.com shows the result on the map, read AUP and UUP explained.
TRA, TSA and CBA
ERNIP Part 3 defines the three reservation types like this:
| Term | Definition | Other traffic while active |
|---|---|---|
| TRA: Temporary Reserved Area | Airspace normally under the jurisdiction of one aviation authority, temporarily reserved by common agreement for the specific use of another aviation authority. | May be allowed to transit, under ATC clearance. |
| TSA: Temporary Segregated Area | Airspace normally under the jurisdiction of one aviation authority, temporarily segregated by common agreement for the exclusive use of another aviation authority. | Not allowed to transit. |
| CBA: Cross-Border Area | An airspace restriction or reservation established over international borders for specific operational requirements. It may take the form of a TRA or a TSA. | As for the TRA or TSA it takes the form of. |
Which type a state publishes depends on the activity. When segregation is needed to protect participating and non-participating traffic, the area is a TSA and tactical crossing should not be allowed while it is active. When the activity does not always need that protection, ERNIP recommends a TRA, so crossings can be allowed tactically.
Some danger areas and restricted areas are managed the same way; ERNIP calls these "AMC-manageable" areas. How a reserved area affects a VFR flight is set nationally, so check the AIP, sections ENR 5.1 and ENR 5.2.
The three FUA levels
FUA works on three levels of airspace management (ASM):
| Level | Name | What happens | Who |
|---|---|---|---|
| 1 | Strategic ASM | National airspace policy: flexible structures such as TRAs, TSAs and conditional routes are designed and published, and priority rules are agreed. | A joint civil-military high-level airspace policy body in each state |
| 2 | Pre-tactical ASM | Day-to-day allocation of the flexible structures for specific periods. | Airspace management cells (AMCs), in coordination with the Network Manager |
| 3 | Tactical ASM | Real-time activation, deactivation or reallocation of the airspace allocated at level 2. | Civil and military ATS units and controlling military units |
In short: TRAs and TSAs are established at level 1, allocated by AMCs at level 2, and activated at level 3 for periods as close as possible to the real use.
How the AUP and UUP allocate them
An Airspace Use Plan (AUP) is an ASM message of NOTAM status that notifies an AMC's daily decision on the temporary allocation of the airspace under its jurisdiction. An Updated Airspace Use Plan (UUP) updates and supersedes the AUP or an earlier UUP. ERNIP Part 3 sets the timetable:
- From D-6 to D-2, AMCs may publish draft AUPs as information becomes available.
- On D-1, each AMC publishes its AUP as soon as possible and no later than 15:00 UTC (14:00 UTC in summer). It covers 06:00 UTC on the day of operation to 06:00 UTC the next day.
- Before a weekend or a holiday period, an AMC may send several AUPs at once, for up to seven consecutive days.
- During the day, UUPs update the plan when activity is cancelled or changed.
- The Network Manager consolidates the national plans into the European AUP and UUP (EAUP and EUUP), published on the NOP Portal and distributed through the NM B2B service.
FUA, the AUP/UUP and DYNAM
FUA is the concept and its procedures; the AUP and UUP are how its day-by-day decisions reach airspace users. When pilots or software speak of "FUA data", they usually mean the AUP and UUP.
FUA data alone does not tell you whether an area is active. Many restricted and danger areas are not managed through FUA at all: they are activated by NOTAM, or have activity times published in the national AIP or an AIP Supplement. An area that does appear in the AUP can still be changed by a NOTAM on the day.
Dynamic Airspace Mapping (DYNAM) on NOTAMbriefing.com combines all of these sources: the AUP and UUP, NOTAMs, and the published schedules in the AIP and AIP Supplements. FUA is one part of DYNAM. The map shows the result of all the sources together, for the time range you choose.
Conditional routes (CDRs)
A conditional route is an ATS route, or a portion of one, that can be planned or used only under specified conditions, often because it crosses a TRA or TSA. CDRs used to come in three categories: CDR1, plannable at times published in the AIP; CDR2, plannable only when made available in the daily plan; and CDR3, usable only on ATC instruction.
Europe has since moved to a single CDR category that removed CDR2 and CDR3. The remaining conditional routes kept the name CDR1: they are available for flight planning at the times and levels published in the national AIP, unless the daily EAUP or EUUP makes them unavailable.
CDRs matter mostly for IFR flight planning. For a VFR pilot, the status of the underlying TRA or TSA is what counts.
Worked example: an illustrative TRA day
The area and times below are invented to show the sequence; they do not describe a real TRA.
- D-2: the AMC publishes a draft AUP showing a TRA planned for military training from 08:00 to 12:00 UTC, from 4 500 ft AMSL to FL100.
- D-1: by 14:00 UTC (summer), the AUP confirms the allocation for the next day.
- Day of operation, 07:30 UTC: the first two hours are cancelled. The AMC issues a UUP: the TRA is now allocated from 10:00 to 12:00 UTC.
- 10:00 UTC: the controlling unit activates the TRA in real time (level 3) and releases it early when the training ends. That release may never appear in a published plan.
- The VFR pilot planning to cross at 11:00 UTC works from the latest UUP, not the AUP, and asks the flight information or ATC unit for the live status before crossing.
Before your next flight
Fold FUA into your briefing:
- Check the latest UUP rather than the AUP; see AUP and UUP explained.
- Use Dynamic Airspace Mapping on the live map to see which reserved areas are active in your time window.
- Read NOTAMs as well: a NOTAM can also activate or change a reserved area. See how to read a NOTAM.
- Look up ASM terms in the NOTAM and airspace glossary.