AA.I.A.K3FAA-S-ACS-11A · Nov 2023Knowledge
Propellers–type, controls, feathering/unfeathering, auto-feather, negative torque sensi...
Propellers–type, controls, feathering/unfeathering, auto-feather, negative torque sensing, synchronizing, synchrophasing, and thrust reverse, including uncommanded reverse procedures.
Bottom line
The pilot of a typical multiengine airplane can feather the propeller of an inoperative engine, and feathering minimizes propeller drag by stopping engine rotation with the blade streamlined with the relative wind. An uncommanded or inadvertent deployment of thrust reversers while airborne is an emergency. Reverse thrust is more effective at high speed than at low speed, so the pilot should use it as soon as is prudent after touchdown.
Key numbers
| Number | What it means |
|---|---|
| parasite drag as great as the entire airframe's, for a propeller windmilling at high speed in the low range of blade angles | Windmill drag |
| two types on a jet engine: target or cascade | Reverser types |
FAA references
- AFH ch. 13 (pp. 13-3–13-5) — FAA-H-8083-3C
- AFH ch. 16 (pp. 16-10–16-11) — FAA-H-8083-3C
- PHAK ch. 2 (p. 2-20) — FAA-H-8083-25C (2023)
- PHAK Glossary — FAA-H-8083-25C (2023)
Build understanding you can use
Unlock the full lesson and continue studying this element.
- Full teaching sections: What it is; Key points; How it is done
- Check your understanding with answers you can reveal
- Common mistakes paired with the FAA facts that correct them