Definition
A flight director display format in which pitch and roll guidance are combined into one symbol — typically a single triangle or wedge — that the pilot flies to by aligning the aircraft reference symbol with it. Contrasted with a cross-pointer (dual-cue) display, which shows pitch and roll as two separate bars.
Plain English
A flight director presentation that shows steering commands as one combined symbol on the attitude indicator. The pilot just flies the aircraft symbol up to that one symbol, and pitch and roll are correct at the same time.
Context Anchor
Seen when reading about helicopter flight directors and AFCS displays used during instrument flight.
Derivation
"Cue" comes from the theatrical sense of a signal telling someone what to do next. "Single cue" simply means there is one such signal on the display rather than two. Knowing this helps because the symbol is literally a single visual prompt telling the pilot where to put the aircraft.
Why Pilots Care
Reduces pilot workload by requiring attention to only one moving element instead of two independent cues during IFR helicopter operations.
Intuition Check
Do not read single cue as one simple warning or one isolated instruction. Here it means one flight display symbol that combines more than one control command.
Example Sentence 1
The helicopter's flight director uses a single cue, so the pilot flies the aircraft symbol up to the inverted triangle to capture the commanded attitude.
Example Sentence 2
The single-cue presentation simplified tracking the localizer and glideslope during the ILS approach in the helicopter.