Landing Gear

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Manufacturing Requirements

The following four sections provide information critical to the manufacturing requirements of the landing gear for each of the aircraft. The maximum allowed load is important to know in order to design a landing gear strut with a suitable cross-sectional area built from a material with optimal mechanical properties for the given max loads.

Boeing 787 Dreamliner

File:B787.png

Below is a table for the maximum allowed loads per strut on the landing gear for specific conditions.

Airplane Model Unit Max Design Taxi Weight Vertical Nose Gear Load Static at Most Forward CG Vertical Nose Gear Load Static + Braking 10 ft/s2 Deceleration Vertical Main Gear Load per Strut at Max Load at Static AFT CG Horizontal Main Gear Load Static + Braking 10 ft/s2 Deceleration Horizontal Main Gear Load per Strut CG at Instantaneous Braking
787-8 kg 228,383 24,819 38,594 104,234 35,468 83,388
787-9 kg 254,692 21,322 34,546 117,736 39,554 94,189
787-10 kg 254,692 19,138 30,939 118,745 39,554 94,996

Boeing 747-8

File:B747.png

Below is a table for the maximum allowed loads per strut on the landing gear for specific conditions.

Airplane Model Unit Max Design Taxi Weight Vertical Nose Gear Load Static at Most Forward CG Vertical Nose Gear Load Static + Braking 10 ft/s2 Deceleration Vertical Main Gear Load per Strut at Max Load at Static AFT CG Horizontal Main Gear Load Static + Braking 10 ft/s2 Deceleration Horizontal Main Gear Load per Strut CG at Instantaneous Braking
747-8 kg 449,056 31,802 54,252 106,299 34,870 85,039
747-8F kg 443,613 29,549 52,789 105,010 34,447 84,008

Airbus A330-700 Beluga XL

File:Beluga.png

Below is a table for the maximum allowed loads per strut on the landing gear for specific conditions.

CG Height Unit Max Design Taxi Weight Vertical Nose Gear Load Static at Most Forward CG Vertical Nose Gear Load Static + Braking 10 ft/s2 Deceleration Vertical Main Gear Load per Strut at Max Load at Static AFT CG Horizontal Main Gear Load Static + Braking 10 ft/s2 Deceleration Horizontal Main Gear Load per Strut CG at Instantaneous Braking
ZCG -0.5 m kg 227,900 23,280 38,150 104,440 35,420 83,550
ZCG -0.4 m kg 227,900 24,700 39,890 104,440 35,420 83,550
ZCG 0 m kg 227,900 24,700 41,170 104,440 35,420 83,550
ZCG 0.4 m kg 227,900 24,700 42,440 103,620 35,420 82,890
ZCG 0.6 m kg 202,300 23,650 39,970 92,710 31,440 74,160

Airbus A380

File:A380.png

Below is a table for the maximum allowed loads per strut on the landing gear for specific conditions.

Weight Variant Unit Max Design Taxi Weight Vertical Nose Gear Load Static at Most Forward CG Vertical Nose Gear Load Static + Braking 10 ft/s2 Deceleration Vertical Wing Gear Load per Strut at Max Load at Static AFT CG Vertical Body Gear Load per Strut at Max Load at Static AFT CG Horizontal Body Gear Load Static + Braking 10 ft/s2 Deceleration Horizontal Body Gear Load per Strut CG at Instantaneous Braking Horizontal Wing Gear Load Static + Braking 10 ft/s2 Deceleration Horizontal Wing Gear Load per Strut CG at Instantaneous Braking
WV008 kg 577,000 40,190 70,590 108,850 163,270 53,800 130,620 35,870 87,080

There are several other weight variants listed for the Airbus A380. WV008 has the largest loads per strut for each landing gear. A complete list of the 15 different weight variants can be founds below.

Wv1.png Wv2.png Wv3.png

Manufacturing and Testing

Safran Landing Systems

Safran Landing Systems (SLS) manufactures landing gear for a wide range of aerospace vehicles including the Airbus A380 and Boeing 787 Dreamliner aircrafts. SLS offers innovative solutions to the Airbus A380's landing gear such as a 350-bar hydraulic system in the retractable nose landing gear, which previously had never been used before on large commercial aircraft. Similarly, SLS has made significant technological advances in the materials used for the Boeing 787 landing gear. Specifically, SLS reduced landing gear weight, reduced corrosion, and provided higher resistance to fatigue versus steel components. Several components in the Boeing 787 landing gear are made from titanium including the inner cylinder of the main gear, which is an industry first.

Performance Testing

Safran Landing Systems (SLS) performs a variety of quality assurance tests for each landing gear. The landing gears are first subject to 150% of the maximum loading conditions that they would be subjected to in commercial service. This provides confidence in the capabilities of a loaded landing gear with a safety factor. SLS also drops the landing gear from a height which generates up to a 3.6576 m/s impact speed on the landing gear. The tested impact speed is above the FAA maximum required impact speed without failure of 3.048 m/s for commercial aircraft. Additionally, SLS conducts rigorous environmental testing for the landing gear to ensure that they will function successfully under extreme conditions. The landing gear in subjected to temperatures ranging from -55℃ to 75 ℃. While conducting low temperature testing, the landing gear must demonstrate that it is able to break through up to 6 mm thick ice while extending and retracting. Other tests are conducted to ensure that the landing gears are resilient to vibrations, corrosion, sand, dust, high intensity frequency pulses, and that they can dissipate the charge from a lightning strike without being damaged or losing functionality.