Interior view of retracted air stairs (partially hidden by extended catwalk). At the end of the catwalk, is the slide pack (yellow rectangular shape), and beyond that is the interior of the tailcone (which, in an evacuation, would be jettisoned). Just beyond the slide pack, to the right, at hip level (and unfortunately, from the camera angle, hidden from view), is the manual tail cone release handle.
As the air stairs are lowered by ramp personnel(controls are on the outside of aircraft), the catwalk simultaneously retracts into the ceiling. The last three steps should unfold automatically, but on occasion, may require an "assist" from someone on the ground. Those additional steps were added to the stairs for the MD-80 series aircraft, due to the fuselage being higher off the ground than that of a DC-9. This came about from the main landing gears re-design to be slightly longer (I believe it may only be a foot increase), than those on the DC-9. This additional height was required when the fuselage was stretched, so there would be no issues with tail strikes during take off rotation.
