TABLE OF CONTENTS Landing gear weight prediction is primarily affected by: design landing weight, hardness of landing surface, landing speed, brake requirements, sink speed, and load-deflection characteristics.
It is apparent that an aircraft's first-flight date, or state-of-the-art (SOTA) date, has an impact upon the prediction no doubt because of the gradual development of materials having higher strength-to-weight ratios. It is noteworthy that, despite the continuing increases in landing speeds and aircraft size, the designer has managed to generally reduce the landing gear weight percentage.
All weight prediction methods are based initially upon statistical data in which actual landing gear weights are reviewed and attempts made to generate equations that fit the data. Consequently, Table 11.1 is presented to allow the reader to observe raw data and, if necessary, to draw conclusions from it.
| Aircraft | Landing gear weight W LG, lb | Design gross weight W G, lb | Landing weight used W L, lb | W LG % of W G | W LG % of W L | K SL | Other K Factor [a] | K LG |
|---|---|---|---|---|---|---|---|---|
| Boeing 707-321 | 11,216 | 312,000 | 207,000 | 3.6 | 5.4 | 1.00 | 1.00 | |
| Boeing 727-100 | 6,229 | 161,000 | 137,500 | 3.9 | 4.5 | 1.00 | 1.00 | |
| Boeing 747 | 31,702 | 708,000 | 564,000 | 4.5 | 5.6 | 1.00 | 1.00 | |
| C-5A | 38,153 | 728,000 | 635,850 | 5.2 | 6.0 | 0.85 | 0.15RF | 1.34 |
| 0.11FL | ||||||||
| 0.19POS | ||||||||
| 0.04PRE | ||||||||
| C-46 | 3,087 | 45,000 | 45,000 | 6.9 |
