Stalls and spins

Accelerated and cross-control stalls, the phases of a spin, and PARE.

22 min read · Advanced aerodynamics

After this lesson you can

  • Explain why the critical AOA never changes while the stall speed changes with load factor, and quote the load factor at 60 degrees of bank.
  • Describe how an accelerated stall and a cross-control stall are set up, recognized, and recovered.
  • Name and describe the four phases of a spin, with the altitude-loss figures the Airplane Flying Handbook (AFH) gives for each turn.
  • Execute the spin recovery sequence, in order, and tell a developing spin apart from a spiral dive.

A spin is not simply a more serious stall. It is a stall with a yaw added to it: one wing more deeply stalled than the other, which creates autorotation - a rotation that feeds itself - on a flight path close to vertical.

A commercial pilot needs to understand this precisely, for two reasons. First, the maneuvers ahead in this course - steep turns, chandelles, lazy eights - are flown with a thin margin above the stall at significant bank angles, exactly where an asymmetry starts to matter. Second, the flight instructor certificate that usually follows a commercial certificate requires spin training under 14 CFR 61.183(i).

The Airplane Flying Handbook (AFH) gives numbers worth memorizing: two to four turns for the incipient phase, roughly 1,000 feet of altitude lost on the first turn and about half that on each turn after it, and a recovery that must be complete no lower than 1,500 feet AGL.

The rest of this lesson

  1. 1.The stall is fixed; the speed at which it happens is not
  2. 2.Accelerated stalls
  3. 3.Cross-control stall
  4. 4.Two more you should recognize: secondary and elevator trim stalls
  5. 5.From a stalled wing to autorotation
  6. 6.The four phases of a spin
  7. 7.PARE, and what PARE leaves out
  8. 8.Spin or spiral dive: do not reach for the wrong fix
  9. 9.What to remember
  10. 10.Airspace and attention: the risks that ride along with every stall
  11. 11.What the stall warning does and does not tell you
  12. 12.The environment: turbulence, microbursts and density altitude near the stall

These 12 sections, their figures, the checks along the way and the end-of-lesson quiz come with the CPL track. Paid once, yours for good.

See what the CPL track costsEvery module 1 is free to read, no account, no card.

Key terms

Try to recall each definition before turning the card.