Task VIII.C
Constant Airspeed Descents
To determine the applicant exhibits satisfactory knowledge, risk management, and skills associated with attitude instrument flying during constant airspeed descents solely by reference to instruments.
References: FAA-H-8083-2, FAA-H-8083-3, FAA-H-8083-15, FAA-H-8083-25
Study Notes
At cruise airspeed: reduce power to the descent setting and simultaneously lower the nose just enough to hold the airspeed, then trim.
At a slower speed: reduce power first, hold altitude while the airplane decelerates to the target speed, then lower the nose to maintain that speed as the descent begins (IFH ch 7).
Same logic as the climb:
- Pitch: airspeed indicator.
- Bank: heading indicator.
- Power: tachometer.
I set attitude and power on the control instruments (AI plus tach), then confirm performance on the rest of the panel (IFH ch 7).
Lead by roughly 10% of the vertical speed (500 fpm down means starting 50 ft above the target), and add power to the cruise setting as I raise the nose — power and pitch together, so the airspeed doesn't decay while the nose comes up. Then trim. Standard: ±200 ft, heading ±20°, airspeed ±10 kt.
- Chasing the airspeed with large pitch changes instead of making small attitude corrections and waiting.
- Forgetting to re-trim after the power change.
- Letting the scan collapse onto one instrument (fixation).
- Blowing through the level-off altitude because I didn't lead it (IFH ch 7).
It lags 6–9 seconds before showing an accurate rate. The initial needle movement is a useful trend, but if I chase the rate itself I'll over-control. Fly the attitude indicator, cross-check the VSI once things stabilize (IFH ch 5).
Three areas:
- Spatial disorientation — a descending turn is the graveyard-spiral setup.
- Collision risk — heads-down under the hood.
- Task prioritization — aviate first, and if the situation deteriorates in real IMC, get ATC help early or declare an emergency.
(PHAK ch 17, AIM 6-1-2)
Official ACS elementsreference
Knowledge5 elements
The applicant demonstrates understanding of:
PA.VIII.C.K1Flight instruments as they relate to:PA.VIII.C.K1aa. Instrument limitations and potential errorsPA.VIII.C.K1bb. Indication of the aircraft attitudePA.VIII.C.K1cc. Function and operationPA.VIII.C.K1dd. Proper instrument cross-check techniques
Risk Management8 elements
The applicant is able to identify, assess, and mitigate risk associated with:
PA.VIII.C.R1Instrument flying hazards, including failure to maintain visual flight rules (VFR), spatial disorientation, loss of control, fatigue, stress, and emergency off airport landings.PA.VIII.C.R2When to seek assistance or declare an emergency in a deteriorating situation.PA.VIII.C.R3Collision hazards.PA.VIII.C.R4Distractions, task prioritization, loss of situational awareness, or disorientation.PA.VIII.C.R5Fixation and omission.PA.VIII.C.R6Instrument Interpretation.PA.VIII.C.R7Control application solely by reference to instruments.PA.VIII.C.R8Trimming the aircraft.
Skills3 elements
The applicant exhibits the skill to:
PA.VIII.C.S1Transition to the descent pitch attitude and power setting on an assigned heading using proper instrument cross-check and interpretation, and coordinated flight control application.PA.VIII.C.S2Descend at a constant airspeed to specific altitudes in straight flight and turns.PA.VIII.C.S3Level off at the assigned altitude and maintain altitude ±200 feet, heading ±20°, and airspeed ±10 knots.