Wheel and Tyre Damage

Handling tyre damage turns on three things: how to suspect it, the effect on performance, and the safety of taxi and approach to the gear. This article also covers how the fusible plug prevents a burst, and a life-saving point: which direction to approach the gear from after a brake overheat or tyre damage.

 Suspect tyre damage? (any sign — none is sufficient or necessary)
  ├ ATC reports tyre debris on the runway
  ├ a bang on take-off (note: could be the engine / gear retraction, not necessarily a tyre)
  ├ an uncommanded yaw on the take-off roll (note: could be a lateral gust)
  ├ TIRE LO PR after take-off (note: the debris may have damaged the pressure sensor too → may not trigger)
  └ amber XX on the WHEEL SD (note: may be another wheel's sensor, not the damaged one)
         │
         ▼  WHEEL TIRE DAMAGE SUSPECTED
  ├ performance: one burst tyre ≈ one brake released → select the ONE/TWO BRK RELEASE failure case (EFB)
  ├ apply the landing-distance procedure
  └ after landing: inspect the gear before taxi · TAXI WITH CARE
         │
  ┌──────┴── taxi limit ──────┐
  two tyres deflated (one main gear / centre gear) → limit NWS to 30° (tiller 3rd graduation)
  no braked pivot turn (article 21)
 ════ protection: fusible plug melts on overheat to deflate (anti-burst) ; approach the gear from the tyre shoulder at an oblique angle · not the rim hazard area ════

1. Suspecting tyre damage — every sign is neither sufficient nor necessary

Per FCTM PR-AEP-LG:

The crew may suspect tire damaged based on several indications... Information from the ATC of the presence of tires debris / A bang noise during the takeoff (Note: A bang noise may not necessarily indicate tire damages...) / A non-commanded sudden yaw (Note: Directional deviation may also come from lateral gusts) / The WHEEL TIRE LO PR alert triggered after takeoff (Note: ...may not trigger in all cases as the tire debris may have also damaged the tire pressure sensor) / The WHEEL SD page showing amber XX (Note: ...may be displayed for other wheels than the damaged ones).

The essence: every sign carries a "note" saying it is neither sufficient nor necessary — a bang could be the engine (a surge) or gear retraction; TIRE LO PR may not trigger (the debris damaged the pressure sensor too — TPIS); the amber XX may point to a neighbouring wheel's sensor. So tyre-damage judgement must combine several clues, not rely on a single signal. It is the classic diagnostic trap of "the sensor may have been damaged by the same event".

2. Performance — one burst tyre equals one brake released

Per a representative QRH / FCTM PR-AEP-LG:

Performance impact of one burst tire is equivalent to one brake released... The flight crew must... select the appropriate failure case: ONE BRK RELEASE failure case if one tire is damaged, TWO BRK RELEASE failure case if more than one is damaged.

Why "one burst tyre ≈ one brake released": a burst wheel loses friction and rolling, equivalent to that position's brake not working — so the landing distance is computed as "one brake fewer". The EFB has this failure case directly; there is no need to estimate.

3. The fusible plug — deflate actively rather than burst

Per FCOM DSC-32-30-10:

Main gear wheels are fitted with fusible plugs which protect against tire burst in the event of overheat.

The mechanism (the standard fusible-plug principle): a brake overheat (Brake Temperature and Cooling) reaches the rim, and a fusible plug at its melting point melts and actively deflates the tyre — turning "a hot, high-pressure tyre held to bursting" into a controlled deflation. This is why some wheels may be seen slowly deflating after BRAKES HOT — the fusible plug saving the day. It is directly tied to brake temperature: one of the real dangers of overheat is a tyre burst, and the fusible plug is the last line of defence.

4. The 30° steering limit for taxiing with deflated tyres

Per FCTM PR-AEP-LG:

if two tires are deflated on the same main gear (maximum one main gear), or on the center gear, the nosewheel steering angle must be limited to a maximum of 30°... A steering handwheel position on the 3rd graduation.

Why limit to 30°: with deflated tyres that gear's load-bearing and side-load capacity is reduced, and the side force of a large-angle turn could destabilise or further damage the deflated-tyre gear — so the steering angle is limited and the tiller graduation gives precise control (the tiller is 72° full scale, and the 3rd graduation is about 30°). Combined with the braked-pivot prohibition of Steering Faults, taxiing with tyre damage means "turn gently, do not pivot in place".

5. A life-saving point — approach from the tyre shoulder, not the rim hazard area

Per AMM 05-51-16:

AFTER BRAKE OVERHEAT OR BRAKE FIRE, APPROACH THE LANDING GEAR WITH EXTREME CAUTION AND FROM AN OBLIQUE ANGLE IN THE DIRECTION OF THE TIRE SHOULDER. DO NOT GO INTO THE RIM HAZARD AREA.

When a tyre or rim bursts, the fragments fly radially out along the rim plane (the wheel's "equator"), so standing to the side (toward the tyre shoulder) is relatively safe, and standing directly fore or aft of the rim (the rim hazard area) risks being struck by high-speed fragments. This is the survival direction for ground personnel — and for the crew walking round the aircraft after evacuation. A tyre burst can be lethal (the AMM warns it "can cause death or injury").

[!warning]- Six misconceptions this article corrects (1) A bang does not by itself mean a burst tyre — it could be the engine or gear retraction; every sign is insufficient on its own. (2) No TIRE LO PR does not mean no tyre damage — the debris may have damaged the pressure sensor too, so it may not trigger. (3) A burst tyre's effect on landing distance is not small — it equals one brake released (select ONE/TWO BRK RELEASE). (4) An overheated tyre is not just left to burst — the fusible plug melts and deflates it actively. (5) Taxiing with tyre damage is not normal steering — two deflated tyres limit NWS to 30° (tiller 3rd graduation), and no braked pivot. (6) You may not approach an overheated/damaged gear from any direction — approach from the tyre shoulder at an oblique angle, never the rim hazard area (radial fragments are lethal).

Self-test

[!note]- Q1. What are the signs of suspected tyre damage, and why is each insufficient?

ATC debris reports, a bang on take-off, an uncommanded yaw, TIRE LO PR after take-off, and amber XX on the WHEEL SD. Each is insufficient: a bang could be the engine; the yaw could be a gust; TIRE LO PR may not trigger if the debris also damaged the sensor; the amber XX may be a neighbouring wheel's sensor. Judgement must combine several clues.

[!note]- Q2. What is the performance impact of one burst tyre, and how is it selected in the EFB?

One burst tyre is equivalent to one brake released — the burst wheel loses friction and rolling. Select the ONE BRK RELEASE failure case for one damaged tyre, or TWO BRK RELEASE for more than one, and apply the landing-distance procedure.

[!note]- Q3. How does the fusible plug prevent a burst, and what is it tied to?

On a brake overheat reaching the rim, the fusible plug melts at its melting point and actively deflates the tyre, turning a potential burst into a controlled deflation. It is directly tied to brake temperature — a tyre burst is one of the real dangers of overheat, and the fusible plug is the last line of defence.

[!note]- Q4. What is the steering limit with deflated tyres?

If two tyres are deflated on the same main gear (or the centre gear), nosewheel steering is limited to a maximum of 30° (the tiller 3rd graduation), because the deflated gear's side-load capacity is reduced. Combined with no braked pivot turn, taxi gently.

[!note]- Q5. From which direction should an overheated/damaged gear be approached, and why?

From the tyre shoulder, at an oblique angle — never the rim hazard area. A bursting tyre/rim throws fragments radially out along the rim plane, so standing to the side is relatively safe while standing fore or aft of the rim risks being struck. A burst can be lethal.

Key takeaways

References

A330 procedures per a representative operator QRH (WHEEL TIRE DAMAGE SUSPECTED — one burst tyre ≈ one brake released, the landing-distance procedure, TAXI WITH CARE), FCTM PR-AEP-LG (the tyre-damage signs with their notes, the ONE/TWO BRK RELEASE failure cases, the 30° steering limit / tiller 3rd graduation), FCOM DSC-32-30-10 (the fusible plug protecting against a burst on overheat), and AMM 05-51-16 (approach from the tyre shoulder at an oblique angle, not the rim hazard area — a burst can cause death or injury). The handling chain is an integrative synthesis. The fusible-plug melt-and-deflate detail follows the standard principle (the wheel-section D/O is not in the source dump); the full FCOM/LIM table for taxiing with deflated tyres is in LIM-LG, and tyre-damage EFB performance figures are performance-layer.

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.