North Country Heli FlightHELICOPTER GROUND SCHOOL · ACS-ALIGNED
Private (PPL-H) · Lesson 32

ACS Alignment

FAA-S-ACS-15 — Private Pilot, Rotorcraft–Helicopter · Area of Operation IX. Emergency Operations · Task: LTE & Antitorque System Failures
PA.IX.F.K1 — LTE conditions & wind azimuths PA.IX.F.K2 — LTE recovery PA.IX.F.K3 — tail-rotor drive/control failure response

Loss of Tail-Rotor Effectiveness & Antitorque Failures

Unanticipated yaw from the wind — and what to do if the tail rotor quits.

By the end of this lesson you can:

1 · LTE / unanticipated yaw

Loss of tail-rotor effectiveness (LTE) is an uncommanded, rapid yaw (usually toward the advancing main-rotor blade) that doesn't stop on its own. It's induced by wind, not a mechanical failure — certain relative-wind azimuths (e.g., winds from the left on a US-rotation helicopter, tailwinds, and weathercock-unstable regions) reduce tail-rotor effectiveness, especially at low airspeed, high power, and out of ground effect. Recovery: apply full pedal against the yaw, lower collective if able (reduces torque demand), and gain airspeed with forward cyclic to restore tail-rotor effectiveness and weathervane stability.

2 · Actual antitorque failures

A true tail-rotor drive or control failure is different from LTE and is handled per the POH. A loss of antitorque thrust generally produces a strong yaw that pedal can't fix; depending on the failure, the response may involve establishing airspeed for weathervaning and performing a running landing or an autorotation. The specific R44 procedures are in the POH and must be learned exactly.

3 · Watch

Curated reference clip — “Helicopter Lesson: LTE — Loss of Tail Rotor Effectiveness,” utahhelicopter (YouTube). Embedded with the creator's player; we don't host or alter it.

4 · Reference sources

Use the authoritative references

📄 FAA Helicopter Flying Handbook, Ch. 11 — Emergencies & Hazards (LTE, tail-rotor failures) 📄 FAA HFH, Ch. 2 — Aerodynamics (antitorque)
Your aircraft: the R44 responses to tail-rotor drive and control failures are in your Robinson R44 POH, Section 3 (Emergency Procedures). LTE is a handling phenomenon, not a malfunction — but verify all failure procedures from the POH.
✍️ Fill in for the aircraft you fly (N-________)
Value / limit:
R44 POH section & page:
Leave blank until you look it up in your R44 POH (see the reference above) and confirm it with your CFI. Aircraft-specific numbers vary with weight & conditions — don’t guess.
Risk management (the “Consider”): LTE bites at low airspeed, high power, OGE, in wind — exactly the hover/approach/pedal-turn regime near the ground. Prevent it: be wary of downwind and left-quartering winds in the R44, avoid unnecessary high-power OGE hovering in wind, and keep some airspeed. If a yaw starts, react immediately with pedal and gain airspeed; don't let it wind up.

5 · Knowledge check