登機梯

thumb|DC-3 modified with a simple airstair thumb|Northwest Airlines [[Boeing 727 with ventral airstair open]] thumb|right|3-section folding airstair on a "Combi aircraft|Combi" [[737-200 aircraft of Alaska Airlines]] thumb|George W. Bush boards a [[VC-25 using the lower-level airstair.]] thumb|The Il-86, a wide-body airliner with airstairs into the lower cargo level. The rear airstair is also visible in this picture. thumb|The airstair on a business jet thumb|There were no passengers to accommodate on this business jet conversion for cargo operations. A manually-placed, folding airstair saved