Hot Brakes at LAX, the DHL Seven Thirty-Seven Freighter Fire, and What Brake Energy Limits Mean for Every Pilot

A DHL Boeing 737-800 freighter landed at Los Angeles International Airport and came to a stop with its main landing gear on fire. Ground crews responded immediately, the crew evacuated, and there were no fatalities. The preliminary indication is an apparent brake malfunction.

What Happened at LAX

Video footage, first reported by AeroTime, shows significant flames - not smoke, not heat shimmer - coming off the main wheel assembly during rollout. ARFF units were on scene. The aircraft stopped, the crew got out, and fire suppression teams handled the situation.

The investigation into root cause is ongoing. Until findings are published, what we have is the incident and the physics behind it.

Why Brake Fires Happen: The Physics of Stopping a Heavy Jet

Brakes do exactly one thing: convert kinetic energy into heat. The 737-800 has a maximum landing weight of approximately 154,000 pounds and approaches the runway at roughly 130 to 140 knots indicated. Stopping that much mass moving that fast generates brake energy measured in the millions of foot-pounds.

The certified brake system is designed and tested to absorb that energy within defined limits. When those limits are approached, exceeded, or when a component fails, the heat has nowhere to go.

Carbon Brakes: Why They’re Different From What You Might Expect

Modern airliners use carbon brake assemblies, not steel. Carbon brake technology became widespread in commercial aviation during the 1980s and 1990s and changed the equation in two important ways: carbon assemblies are lighter - sometimes by several hundred pounds per aircraft - and they have significantly higher heat capacity than steel.

The counterintuitive behavior: cold carbon brakes are less effective than warm ones. They perform better at high temperatures. Pilots transitioning from steel-brake types to carbon-brake types sometimes need to recalibrate their expectations during the first few brake applications of a flight.

Even so, carbon brakes have a ceiling. At some point the assembly glows, the wheel rim heats, and the tire sidewall begins to soften.

The Tire Explosion Hazard

A main gear tire on a 737 is inflated to approximately 200 pounds per square inch. When the tire material softens from heat and internal pressure has nowhere to go, the failure is not a gradual deflation - it is explosive. Debris can travel hundreds of feet. This has killed mechanics and ramp personnel.

To control this, aircraft wheel assemblies incorporate thermal fuse plugs: engineered weak points in the wheel rim that melt at a defined temperature threshold, deliberately deflating the tire before it reaches explosive failure temperatures. A flat tire is an inconvenience. An exploding tire is a catastrophe. The fuse plug exists to enforce that choice.

Whether the fuse plugs activated on the DHL aircraft, or whether the fire developed faster than they could respond, the investigation will determine.

The Three Most Common Pathways to a Brake Fire

1. Rejected takeoff (RTO). The most energy-intensive scenario in aviation. A full-power abort at or near decision speed on a heavy aircraft dumps enormous energy into the brakes in seconds. Boeing’s documentation for the 737 is explicit: after a max-energy RTO, do not move the airplane and do not set the parking brake. Wait for emergency services to come to you. Even if no flames are visible, the brakes are at extreme temperatures. Setting the parking brake traps heat; moving the aircraft while wheels are hot increases ignition risk.

2. Dragging brake. A brake that is partially applied during the approach builds heat before the wheels even touch the runway. The cause might be a faulty brake valve, a hydraulic anomaly failing to fully release, or a brake control system fault. By the time the crew applies deliberate braking on rollout, the assembly is already at elevated temperature and the additional energy pushes it past the limit.

3. Anti-skid malfunction. The anti-skid system modulates brake pressure many times per second to prevent wheel lockup. A locked, sliding wheel is actually less effective at stopping the aircraft than a controlled, rolling, braking wheel - counterintuitive, but that is how friction physics work at these speeds and loads. When anti-skid fails and a wheel locks, concentrated heat builds in one section of the brake assembly rather than distributing across it. Localized heat escalates much faster.

A fourth, particularly insidious pathway: trapped hydraulic pressure from a valve that fails to fully release keeps a brake partially applied with no cockpit indication - until the brake temperature display climbs or a ground observer calls smoke on the radio.

Brake Temperature Monitoring and Cooling Schedules

Modern transport aircraft carry brake temperature monitoring systems that report wheel assembly temperatures to the flight deck in real time. Crews can detect a dragging brake or an overworked assembly before it becomes a fire.

Brake cooling schedules - published in the aircraft’s approved documentation - determine the minimum cooling time required before the next departure based on the estimated brake energy absorbed during landing. This is not a formality. It is a hard limit grounded in thermal dynamics. An aircraft that departs before brakes have cooled to within certified limits is flying on a system that may not perform to specification if maximum braking is needed again.

The Freighter Factor

The 737-800 was designed as a passenger transport. DHL operates converted versions under Boeing’s Converted Freighter program, with structural reinforcement, cargo door installation, and interior reconfiguration - all engineered and certified.

The operational difference matters. Freighters routinely operate at or near maximum landing weight because cargo economics reward maximum payload utilization. A passenger carrier might fly a half-full aircraft on a thin route. A freighter is almost always loaded close to its limits. More landing weight means more brake energy on every leg, more cumulative thermal stress on brake components, and a maintenance program that must rigidly adhere to inspection and replacement intervals.

What LAX’s ARFF Capability Means

Every commercial airport certificated under FAR Part 139 is required to maintain Aircraft Rescue and Firefighting capability scaled to the size and type of operations at that facility. At LAX, which handles widebody international traffic continuously around the clock, that capability includes multiple specialized apparatus carrying thousands of gallons of water and foam, with crews trained specifically in aircraft firefighting, positioned to reach any point on the airport within a defined response time.

When a brake fire call comes in at a place like LAX, the response is not improvised. Those crews know brake fire protocol, approach angles for working around hot landing gear, and the hazards of pressurized tires at elevated temperatures.

Why This Matters If You Fly General Aviation

The scale is different. The consequences of a brake problem in a light airplane are generally less severe than on a heavy transport. The physics are identical.

Brake fade is real in general aviation aircraft. It occurs when brake fluid absorbs enough heat to begin vaporizing. Hydraulic fluid is effectively incompressible when liquid - that is how it transmits force from foot to caliper. When it vaporizes, it becomes compressible, and the pedal gets soft. Brakes respond less than they should. This typically builds gradually during a series of touch-and-goes on a hot summer afternoon, and some pilots attribute the soft feel to technique or to the aircraft rather than to accumulated heat.

Practical habits that prevent it:

• Keep heels on the floor on final approach. Riding the toe brakes while simultaneously adding power generates heat before the wheels ever touch down. Use flaps for drag. Use throttle for energy management.
• Brake deliberately, not continuously. Light, continuous braking from touchdown to turnoff generates more accumulated heat than a shorter, firmer application at a lower speed. Let the aircraft decelerate aerodynamically in the early part of the rollout, then apply brakes once speed is already lower.
• Know your elevation. At airports 5,000 feet or higher, density altitude reduces aerodynamic braking. The brakes have to do more of the work. Do not expect the same rollout you get at your home sea-level field.
• After any rejected takeoff - even at 60 knots in a light aircraft - pause before attempting another. Brake assemblies need time to shed heat before they are ready to perform at full capacity again.

If you are doing touch-and-goes and the brakes start feeling less positive, pedal travel seems longer, or you smell anything unusual during taxi back: end the session. Let the brakes cool. The lesson you lose by stopping early is nothing compared to the situation you can create by continuing with degraded braking on a short runway.

If You See Smoke or Smell Burning After Landing

The procedure is straightforward regardless of what you fly. Stop the aircraft. Do not taxi further. Get on frequency and tell ground control or the tower what you are seeing. Request ARFF if there is any doubt. Do not attempt to assess on your own whether it is serious enough to involve emergency services. Stop, communicate, and let the professionals evaluate it.

Key Takeaways

• A DHL Boeing 737-800 freighter sustained a main gear fire after landing at LAX; the crew evacuated and there were no fatalities. The investigation is ongoing.
• Brakes convert kinetic energy into heat - and every aircraft, from a widebody freighter to a Cessna, operates under the same thermal physics.
• Thermal fuse plugs are engineered into wheel rims to deflate tires before heat can cause an explosive failure; a flat tire is the designed outcome, not a catastrophe.
• The three primary pathways to a landing brake fire are a dragging brake, anti-skid malfunction, and trapped hydraulic pressure - each can be present with little or no cockpit warning.
• In GA aircraft, brake fade from repeated touch-and-goes on hot days is real: use aerodynamic deceleration first, brake deliberately at lower speed, and stop the session if pedal feel degrades.