| 摘要 |
<p>The integral retractable undercarriage for boats can be with or without propulsion equipment. It comprises a number of watertight boxes secured over hull openings and housing wheels on pivotable, extendable or folding mountings. Lowering and raising of the wheels may be manual or, in the case of larger boats, powered. The hull openings are sealed by flaps flush with the outside when closed and actuated conventionally by the undercarriage operating mechanism. The undercarriage can be arranged to permit towing the boat like a trailer.</p> |
