Tailpipe Fire — Cause, QRH Handling, and How It Differs from ENG FIRE
A start-specific extreme: a tailpipe fire — fuel burning in the tailpipe/aft of the turbine. The key points are that it is not a nacelle fire (ENG FIRE) and that it is handled by a dry-crank blow-out, not the fire bottles.
1. Tailpipe fire vs nacelle fire
| Tailpipe fire | Nacelle fire (ENG FIRE) | |
|---|---|---|
| Location | tailpipe / aft of turbine (inside the core gas path) | inside the nacelle (fire zone) |
| Detection | the fire detectors do not see it (detectors are in the nacelle, 12 five sensing elements) | FDU dual-loop detection |
| Cause | residual fuel ignited during start | flammable-fluid leak burning in the nacelle |
| Handling | cut fuel + dry-crank blow-out | ENG FIRE pb 8 actions + fire bottles (ATA 26) |
| Fire bottles | not used (the bottles target the nacelle) | used |
2. QRH handling
ENGINE TAILPIPE FIRE — CAUTION: External fire agents can cause severe corrosive damage. Consider the use of external fire agents only if the following procedure does not stop engine tailpipe fire. ‐ ENG MASTER (affected engine) ... OFF ‐ ESTABLISH AIR BLEED PRESS ‐ BEACON ... ON ‐ When N3 < 30 %: ENG START sel ... CRANK; ENG MAN START pb (affected engine) ... ON ‐ When fire stopped: ENG MAN START pb (affected engine) ... OFF
Per the QRH ENGINE TAILPIPE FIRE procedure:
ENG MASTER OFF → cut fuel (starve the fire of fuel)
ESTABLISH AIR BLEED PRESS + BEACON ON → ready the blow-out air + warn the ground (tailpipe torching is visible)
When N3 < 30 %:
ENG START → CRANK
ENG MAN START → ON → dry crank: motor the engine + use bleed to blow out the residual tailpipe fire ([07](./ata-70-07-starting-system.md))
When fire stopped:
ENG MAN START → OFF
[!warning]- The core: cut fuel + dry-crank blow-out, not the fire bottles A tailpipe fire is inside the core gas path; the engine fire bottles target the nacelle fire zone and do nothing for a fire inside the tailpipe → handle it by cutting fuel + dry-cranking (bleed blow-out) (QRH). This is the 07 "dry crank ventilates fuel vapour" logic applied to firefighting. External fire agents are corrosive — only if the procedure fails (QRH CAUTION).
3. Counterintuitive points
[!warning]- The tailpipe torches but ENG FIRE does not warn — don't wait for ECAM A tailpipe fire is in the core gas path; the nacelle fire detectors (12) cannot see it → no ENG FIRE ECAM. It is usually spotted by ground crew / tower / visually. Don't dismiss it because there is no ENG FIRE warning.
[!warning]- Dry-crank blow-out, and only crank at N3 < 30 % After cutting fuel, only at N3 < 30 % do ENG START → CRANK + MAN START ON for the dry crank (QRH) — using bleed to blow out the residual fire, not the bottles. BEACON ON warns the ground.
Self-test
[!note]- Q1. Why does a tailpipe fire not trigger ENG FIRE? The fire is in the core gas path (tailpipe / aft of turbine); the nacelle fire detectors (12) cannot see it → no ENG FIRE ECAM.
[!note]- Q2. The core handling actions? ENG MASTER OFF (cut fuel) → establish air bleed press + BEACON ON → at N3 < 30 % ENG START → CRANK + MAN START ON (dry-crank blow-out) → MAN START OFF when out.
[!note]- Q3. Why not discharge the engine fire bottles? The bottles target the nacelle fire zone and do nothing for a fire inside the core gas path; a tailpipe fire is handled by cutting fuel + dry-cranking.
[!note]- Q4. When are external fire agents considered? Only if the procedure does not stop the fire (CAUTION: external agents are severely corrosive).
Key takeaways
| Point | Detail |
|---|---|
| Tailpipe fire | residual fuel burning in the core gas path; fire detectors do not see it (≠ nacelle fire) |
| Handling | cut fuel + establish bleed + BEACON + at N3 < 30 % dry-crank blow-out + MAN START OFF when out |
| Bottles | not used (those target the nacelle); external agents only if the procedure fails (corrosive) |
References
- QRH ENGINE TAILPIPE FIRE — handling: MASTER OFF / establish air bleed press / BEACON ON / N3 < 30 % CRANK + MAN START ON (dry-crank blow-out) / MAN START OFF when out / CAUTION external agents corrosive (operator-specific data removed).
- FCOM DSC-70-80-30 (07) — dry-crank ventilation logic.
- FCOM DSC-26-20-10 (12) — nacelle fire-detector location (it cannot see a tailpipe fire).
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.