Definition
An instrument approach operation in which aircraft are cleared for approaches to parallel runways where the runway centerlines are separated by less than 4,300 feet, and where radar separation between aircraft on adjacent final approach courses is required. Aircraft on one final cannot pass abeam aircraft on the adjacent final inside a specified distance; staggered separation is maintained between the two streams of traffic.
Plain English
Two streams of arriving aircraft are landing on side-by-side runways at the same time, but the runways are close enough together that controllers must keep the aircraft staggered — one slightly ahead of the other — rather than allowing them to fly side by side.
Context Anchor
You may see this term in airport arrival procedures, controller instructions, or airport information when a busy airport is landing aircraft on parallel runways.
Derivation
‘Dependent’ comes from Latin dependere, ‘to hang from.’ Here it captures the idea that the spacing of one aircraft depends on the position of the other — neither aircraft can be sequenced without reference to the traffic on the adjacent final.
Why Pilots Care
Knowing the approach is dependent (rather than independent) tells the pilot that ATC is actively staggering arrivals, so speed assignments and tight spacing instructions are normal and must be flown precisely. Deviating from assigned speeds or courses can collapse the staggered separation between the two parallel streams.
Grounding Statement
Picture two airplanes descending toward two side-by-side runways at the same time, with air traffic control keeping them staggered so they remain properly separated.
Intuition Check
Simultaneous does not mean “uncontrolled” or “free to ignore the other runway.” Parallel does not mean independent here; dependent means the two approach streams are linked by required spacing.
Example Sentence 1
Approach advised us to expect simultaneous dependent approaches to runways 28L and 28R, so we were ready for tight speed control on final.
Example Sentence 2
The controller advised the second aircraft to slow to maintain the required stagger for the simultaneous dependent parallel approach.