System Interfaces — Cross-Chapter Coupling with Nine Systems
Articles 00–12 built the engine, and kept running into other systems — bleed, fuel, hydraulics, fire. This article gathers those interfaces into one map, so it is clear at a glance which systems an engine action touches, and how a system failure feeds back into the engine. It is a synthesis — it introduces no new fact, every interface tracing to a verbatim source in 00–12.
1. The interface map
┌─ ATA 22 (A/THR ← FMGS) ─┐
│ │ thrust command
ATA 28 fuel ──supply──►┐ ▼
ATA 36 bleed ◄─draw/supply─┤ ┌──────────┐
ATA 24 elec ◄─IDG gen──┤ │ Engine │──ECAM──► ATA 31 (E/WD+SD)
└FADEC power►┤ Trent 700 │ +FADEC │
ATA 29 hyd ──blue1/yel2──►┤ (reverser) └────┬─────┘
ATA 27 FCTL ─PRIM reverse►┤ │
ATA 32 L/G ─LGCIU on-gnd─►┘ │ ENG FIRE pb (8 actions)
▼
ATA 26 fire ─► cuts: fuel / hydraulics / bleed / PFCV (ATA 21) / FADEC power / IDG (ATA 24)
2. What the engine draws
| Interface | Carries | Source article |
|---|---|---|
| ATA 28 fuel | tank fuel → LP shut-off valve | 04 (DSC-70-40-10) |
| ATA 36 bleed | start air + surge/cooling air | 08 (DSC-70-60), 07 (AMM 80-13) |
| ATA 29 hydraulics | blue 1 / yellow 2 actuate reverse | 09 (DSC-70-70) |
| ATA 24 electrics | aircraft network → FADEC (GND PWR) | 11 (DSC-70-90-30) |
| ATA 22 autoflight | A/THR sets thrust via FMGS | 03 (DSC-70-35-10) |
| ATA 27 flight controls | PRIM 1/3 reverse TLA signal | 09 (DSC-70-70) |
| ATA 32 landing gear | LGCIU on-ground (deploy/start) | 09 (DSC-70-70) |
3. What the engine supplies
| Interface | Carries | Source article |
|---|---|---|
| ATA 36 bleed | engine bleed → pneumatic (a/c, anti-ice, start) | 08 (DSC-70-60) |
| ATA 24 electrics | IDG driven by the engine | 12 (DSC-26-20-20: deactivate IDG) |
| ATA 31 ECAM | N1/N3/EGT/EPR → E/WD, N2/OIL/VIB → ENG SD | 10 (DSC-70-90-40) |
4. The fire-cut — one button, six couplings
The ENG FIRE pb simultaneously cuts fuel (04) / hydraulics (09) / bleed (08) / PFCV–air-conditioning (ATA 21) / FADEC power (11) / IDG–electrics (ATA 24)) — the eight verbatim actions of 12. The densest cross-chapter coupling point.
5. Bidirectional backfire and counterintuitive points
| Interface | Backfire | Fault article |
|---|---|---|
| hydraulics ↔ reverse | blue/yellow loss → that engine's reverse unavailable | 09, 29 |
| bleed ↔ start | insufficient bleed → weak starter | 07, 18 |
| FADEC power ↔ control | cut FADEC power (ENG FIRE) → loss of engine control | 11, 12 |
| ENG FIRE ↔ whole engine | one button cuts six energy classes | 12, ATA 26 |
[!warning]- The engine is not an island — one ENG FIRE pb moves six systems One ENG FIRE push affects fuel / hydraulics / bleed / air-conditioning / FADEC power / IDG (12) — the engine is deeply coupled to the aircraft. When reading a fault, ask whether the engine problem reaches into other systems.
Self-test
[!note]- Q1. What does the engine draw from other systems? Fuel (28), bleed (36), hydraulics (29, reverse), electrics (24, FADEC power), A/THR command (22), PRIM reverse signal (27), LGCIU on-ground (32).
[!note]- Q2. What does the engine supply? Bleed → pneumatic (36), IDG generation (24), ECAM parameters (31).
[!note]- Q3. The most typical bidirectional backfire? Hydraulics ↔ reverse (blue/yellow loss → reverse unavailable, 09); ENG FIRE ↔ whole engine (one button cuts six energy classes, 12).
[!note]- Q4. Where do this article's interfaces come from? All from 00–12 verbatim (each tracing to a source article + FCOM/AMM origin) — a synthesis with no new fact.
Key takeaways
| Point | Detail |
|---|---|
| Coupling | draws (fuel/bleed/hydraulics/electrics/A-THR/PRIM/LGCIU) + supplies (bleed/IDG/ECAM) |
| ENG FIRE pb | the densest coupling point (one button, six energy classes) |
| Backfire | hydraulics↔reverse, bleed↔start, FADEC power↔control |
References
- All interfaces are a synthesis of verbatim sources from 00–12: DSC-70-40-10 (04), DSC-70-60 (08), DSC-70-70 (09), DSC-70-35-10 (03), DSC-70-90-30 (11), DSC-70-90-40 (10), DSC-26-20-20 (12).
- Engine-and-associated-systems overview diagram (FCOM) — reused as the interface base.
Independent study material, not an Airbus publication and not endorsed by the manufacturer. Always defer to the current operator FCOM, FCTM, and QRH for operational use.