27,069 service difficulty reports for the Boeing 747 across 39 systems (1995–2026).
Reported systems
| System | ATA | Reports | Share |
|---|---|---|---|
| Lights | ATA 33 | 9,136 | 33.8% |
| Fuselage | ATA 53 | 8,095 | 29.9% |
| Wings | ATA 57 | 2,802 | 10.4% |
| Doors | ATA 52 | 1,073 | 4% |
| Equipment & Furnishings | ATA 25 | 839 | 3.1% |
| Stabilizers | ATA 55 | 608 | 2.2% |
| Landing Gear | ATA 32 | 503 | 1.9% |
| Nacelles & Pylons | ATA 54 | 474 | 1.8% |
| Fire Protection | ATA 26 | 446 | 1.6% |
| Air Conditioning | ATA 21 | 377 | 1.4% |
| Engine - Turbine/Turboprop | ATA 72 | 373 | 1.4% |
| Flight Controls | ATA 27 | 336 | 1.2% |
| Engine Exhaust | ATA 78 | 259 | 1% |
| Fuel | ATA 28 | 207 | 0.8% |
| Electrical Power | ATA 24 | 175 | 0.6% |
| Hydraulic Power | ATA 29 | 158 | 0.6% |
| Navigation | ATA 34 | 139 | 0.5% |
| Oxygen | ATA 35 | 127 | 0.5% |
| Engine Fuel & Control | ATA 73 | 124 | 0.5% |
| Indicating & Recording | ATA 31 | 99 | 0.4% |
| Communications | ATA 23 | 93 | 0.3% |
| Power Plant | ATA 71 | 84 | 0.3% |
| Windows | ATA 56 | 78 | 0.3% |
| Standard Practices - Structures | ATA 51 | 69 | 0.3% |
| Ice & Rain Protection | ATA 30 | 66 | 0.2% |
| Auxiliary Power Unit (APU) | ATA 49 | 65 | 0.2% |
| Pneumatic | ATA 36 | 53 | 0.2% |
| Engine Oil | ATA 79 | 44 | 0.2% |
| Starting | ATA 80 | 35 | 0.1% |
| Water & Waste | ATA 38 | 33 | 0.1% |
| Engine Air | ATA 75 | 30 | 0.1% |
| Auto Flight | ATA 22 | 30 | 0.1% |
| Engine Indicating | ATA 77 | 18 | 0.1% |
| Other | ATA 14 | 13 | 0% |
| Ignition | ATA 74 | 3 | 0% |
| Engine Controls | ATA 76 | 2 | 0% |
| Other | ATA 37 | 1 | 0% |
| Central Maintenance System | ATA 45 | 1 | 0% |
| Placards & Markings | ATA 11 | 1 | 0% |
Report counts reflect fleet size and reporting activity, not relative safety or reliability. Source: FAA Service Difficulty Reporting System (public domain).