Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Steep Turns — Theory Part 2:

Flying Steep Turns, the Spiral Dive and Sideslipping

CASA Recreational Pilot License (Aeroplane) — CASA Sample Syllabus Lesson 18, Theory Part 2

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Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Where we left off

A head-on diagram of an aeroplane banked in a level turn showing the total lift tilted, split into a vertical component balancing weight and a horizontal component turning the aeroplane, with weight acting straight down.

From Part 1:

  • The horizontal component of lift turns the aeroplane
  • Load factor rises with bank — 60° = 2 g
  • Stall speed rises with √(load factor) — 41% higher at 60°
  • If the nose drops, reduce bank first, then raise the nose

Now we put it to work — and see what happens when a steep turn goes wrong.

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Theory Lesson Overview — Part 2

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Learning Objectives — Part 2

By the end of this session, our aim is to be able to:

  • Describe how to fly a steep level turn and a steep descending turn
  • Explain the difference between a maximum-rate and a minimum-radius turn
  • Describe the cause, symptoms and recovery of a spiral dive
  • Describe how a sideslip works, its uses, and its precautions and limitations
  • Demonstrate First experience of steep turns, spiral-dive recovery and sideslipping in flight
Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Waypoint 1 — Steep Level and Descending Turns

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

The steep level turn

A steep turn is one at 45° of bank or more. Flying it well is similar to the medium turn — with some additions:

Phase What changes from a medium turn
Entry Lookout, then roll in; add power progressively as bank increases, to hold speed against the extra drag
Holding More back pressure to keep the nose on the horizon; balance with rudder
Nose drops Reduce bank first, raise the nose, then re-establish the bank
Recovery Anticipate the roll-out ~half the bank angle early; reduce power to cruise and ease forward to hold the nose position

Start at 45°, build to 60° — about the steepest a training aeroplane can sustain in level flight.

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

The steep descending (gliding) turn

Flown at idle or low power — an excellent test of coordination:

  • Select a speed about 10 kt above the normal glide speed (check your type)
  • A steep nose-down attitude is needed to hold that speed at a steep bank
  • If the speed builds too high, reduce bank first, then adjust the attitude
  • Cross-check the instruments — the steep nose-down picture makes the gliding attitude hard to judge by eye
  • Recover: reduce bank, raise the nose to the correct glide attitude and speed

The steep gliding turn is where a mishandled recovery can slide into a spiral dive — which is exactly what we look at next.

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Waypoint 2 — Maximum-Rate and Minimum-Radius Turns

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Maximum-rate and minimum-radius turns

Both turns are flown right at the stall buffet — the tightest the wing can turn for the power set:

  • Maximum-rate turn — highest bank the power allows, at the buffet: the fastest change of heading the aeroplane can achieve
  • Minimum-radius turn — slowest safe speed, at the buffet: the smallest circle it can fly

Mostly a coordination exercise and a demonstration of the aeroplane's limits — and useful for extreme traffic avoidance.

CASA calls the "maximum rate turn" the turn done at full throttle, banking to the buffet point. So steep turning at full power. But is that really the turn that produces the maximum rate (degrees per second, or time for a full circle)?

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

But is it really maximum-rate vs minimum-radius?

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Flying at the buffet

The technique for both is the same:

  1. Lookout — clear the airspace thoroughly; visibility is poor in a steep turn
  2. Roll into a steep bank and add the power for the turn you want
  3. Increase back pressure until you feel the stall buffet (judder)
  4. Relax the back pressure just enough to stop the buffet — fly right at the threshold, not through it
  5. Any tendency to lose control: release back pressure and reduce bank with aileron

Fly the aeroplane to the buffet — never through it. The buffet is the edge; we ride it, we don't cross it.

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Waypoint 3 — The Spiral Dive

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

What is a spiral dive?

A spiral dive is a steep, descending, over-banked turn where the speed is increasing — the wing is not stalled, but the aeroplane is heading rapidly toward the ground and building load.

How it happens:

  • A steep turn where the nose is allowed to drop and the bank steepens
  • The pilot pulls back to raise the nose — which only tightens the turn and steepens the dive
  • Speed, rate of descent and 'g' all build together

A spiral dive is a nose-low unusual attitude — and pulling harder makes it worse. It must be recognised early.

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Why applying backpressure makes a spiral dive worse

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Spiral dive versus spin — don't confuse them

Spiral dive Spin
Wing Not stalled Stalled
Airspeed High and increasing Low, steady (near stall)
Load factor High and building Low
Key danger Overspeed / overstress Continued rotation, height loss
Pitch action Do not pull until wings level Already stalled — unstall first

The most important difference: in a spiral dive the ASI is winding up. That rising airspeed tells you the wing is flying — so level the wings before you pull.

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Recovering from a spiral dive

The recovery, in order:

  1. Power — close the throttle (idle) to stop the speed building
  2. Roll the wings level with coordinated aileron and rudder
  3. Ease out of the dive — smoothly raise the nose to the horizon
  4. Once under control — cruise power, resume normal flight

Wings level first, then ease out. Pulling while still banked just tightens the spiral and piles on the 'g'.

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Waypoint 4 — Sideslipping

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

What is a sideslip — and why use it?

A sideslip is a deliberately unbalanced manoeuvre: the aeroplane is banked one way with opposite rudder holding the nose from turning.

Its uses:

  • Increase the rate of descent without gaining speed — a steep, draggy way down
  • Lose height on an approach if you are high, especially with a flap failure or in an aircraft without flap
  • Correct for drift into wind on landing (an alternative crosswind technique)

Where have we already used a side-slip in our lessons so far?

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Flying a straight sideslip

The control inputs:

  1. Bank with aileron toward the lower wing (into wind, for a crosswind)
  2. Opposite rudder to stop the nose yawing — hold the heading you want
  3. Elevator to hold the airspeed — the nose attitude will look unusual
  • More bank → more rudder needed. The limit is full rudder — beyond it the nose yaws toward the low wing
  • Expect a high rate of descent and an unbalanced ball — that is the point of the manoeuvre
  • Recover: level the wings with aileron, centre the yaw with rudder, hold the glide speed with elevator

Guard the airspeed all the way through — especially in the recovery, where it is easy to let it decay.

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Sideslip — precautions and limitations

Sideslipping has real limits — respect them:

  • Only where the flight manual permits — some types prohibit it, or prohibit it with flap extended. Check your POH / flight manual
  • Not at low altitude to learn or explore — a mishandled recovery, or a stall from the unusual attitude, needs height
  • Fuel — a prolonged sideslip on a low tank (with the low wing's tank selected) can cause fuel starvation
  • Airspeed — the unusual attitude can mislead; fly a known safe speed

The hazard of a sideslip at low altitude is real (CASA A6 4(j)) — practise it high, and only apply it low once it is solid.

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Waypoint 5 — Recap

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

What do you remember?

  • Describe the two things that change when you fly a steep level turn instead of a medium one
  • Explain the difference between a maximum-rate and a minimum-radius turn
  • Name the one instrument reading that tells a spiral dive from a spin
  • List the spiral-dive recovery, in order
  • Describe the three control inputs that set up a straight sideslip
Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Summary — Full Lesson

Topic Key point
Steep turns 45–60° bank; add power and back pressure; if the nose drops, reduce bank first
Max-rate / min-radius Both flown at the buffet — for a given limiting angle/load, they're both at the buffet point (just above stall). Flap will help.
Spiral dive Un-stalled, speed increasing; recover power–wings level–ease out, in that order
Sideslip Bank one way, opposite rudder, speed with elevator; only where the POH permits, and not low
Underpinning it all Load factor rises with bank; stall speed is 41% higher at 60°; keep it balanced
Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Objectives Check

Can you:

  • Describe how to fly a steep level turn, and a steep descending turn?
  • Explain the difference between a maximum-rate and a minimum-radius turn?
  • Name the instrument that distinguishes a spiral dive from a spin, and give the recovery in order?
  • Describe the control inputs and the main limitations of a sideslip?
  • Feel ready to experience all of these in the air today?
Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Arrival

Steep Turns — Theory Part 2: Flying Steep Turns, Spiral Dive and Sideslipping

Questions?

Any questions before the pre-flight brief?

Part 2 applies the load-factor theory from Part 1 to the manoeuvres the student will fly: the steep level and descending turns, the maximum-rate and minimum-radius turns, recognising and recovering from a spiral dive, and sideslipping. Part 1 covered the aerodynamics — forces in a turn, load factor, and the higher stall speed. Have that fresh; this part assumes it.

Keep this brief — Part 1 is fresh. It re-uses the Part 1 force diagram. The one line to land again: at 60 degrees the wing carries twice the weight and stalls 41% faster. Everything in Part 2 rests on it.

About 27 minutes for Part 2. With Part 1 (~26 min) this uses the full 0.8 hr theory window — trim the manoeuvre detail if time is short, since it is reinforced again at the pre-flight brief and in the air.

These map to CASA lesson-18 elements A5.3 (turn aeroplane steeply), A6.6 (recover from nose-low unusual attitudes — spiral dive), and A5.4 (sideslip aeroplane, where the flight manual permits). The strikethrough on the final objective is deliberate: this is the student's first exposure to these manoeuvres, not an assessed competency.

Click Direct-To to arrive at Steep Level and Descending Turns.

FIM background (Turning, Steep Level Turns): enter as for a medium turn but increase power progressively as bank increases; greater back pressure is needed; if the nose sinks, reduce bank before raising the nose; on recovery, power back to cruise and a positive forward movement of the control column is needed. The maximum sustainable bank is set by the power available — beyond about 60 degrees most training aeroplanes cannot hold height. Demonstrate 45 degrees first; build to 60 as the student progresses.

FIM background (Turning, Steep Descending Turns): fly ~10 kt above normal glide speed; if the speed increases too much, first reduce the angle of bank then adjust; interpret the steep nose-down attitude and high rate of descent from the instruments. On a prolonged glide, clear the engine (open to cruise power briefly) about every 1,000 ft. This slide is the natural bridge into the spiral dive: an over-banked, nose-low gliding turn with the speed building is a spiral dive in the making.

Click Direct-To to arrive at Maximum-Rate and Minimum-Radius Turns.

FIM background (Maximum Rate and Minimum Radius Turns): the aircraft is flown at the threshold of the stall — feel the judder, then relax back pressure just enough to stop it. Full power gives the maximum rate (?) I don't think this is true, but it's called the maximum rate turn; a reduced power setting with take-off flap gives the minimum radius (do not overspeed the flap). Recovery is as from a steep level turn.

Pin the initial 70kt 45 degree. Ask: How can we decrease our radius? (Note: assume that 60 degrees is our limit for level flight) - maybe slowing down? Do so until buffet - maybe banking? Do so until buffet - then increase speed to continue to 60 deg. Ask: How can we increase our rate of turn? - maybe increasing our speed? - no, on it's own it doesn't help - maybe banking? Yes - do so until buffet - then increase speed to continue to 60 deg. If we're limited by a maximum angle (either because of the limiting load factor, or because we can't sustain level flight), then the maximum-rate *and* minimum radius will always be found at the same place: the buffet point just above the stall. Even adding flaps so we can slow down for a smaller radius still increases our rate yet again. So it is really one technique: slowest speed above the stall for a given angle/load.

CASA HF/NTS: undesired aeroplane state — prevention, identifying, controlling [NTS2 4(e)]. A3 4(g): hazards when performing performance manoeuvres. Reassuring framing: the buffet is expected and normal in this exercise — it is the wing telling us we are at the limit. The skill is holding the aircraft exactly there. If it stalls or a wing drops, the recovery is the same one practised in Lesson 5.

Click Direct-To to arrive at The Spiral Dive.

CASA A6.6: recover from nose-low unusual attitudes (spiral dive recognition and recovery). This connects directly to Part 1's attitude-flying slide: using elevator alone to raise a dropped nose in a steep turn tightens the turn — the exact entry to a spiral dive. Plant the distinction now, cover it fully on the next slide: a spiral dive is fast and un-stalled; a spin is slow and stalled. They look alarming in similar ways but need opposite pitch responses.

First show a 30 degree angle of bank, and how adding backpressure predominently increases lift. Next show a 60 degree angle of bank, and how adding backpressure now predominently increases the centripital force. By pulling back in a steep turn, we are *increasing* the centripital force, tightening the spiral. We need to straighten up before pulling back to avoid this.

This comparison is the crux of the spiral-dive brief. The instinctive response to a nose-low, ground-filling-the-windscreen picture is to pull — which is correct for neither, but is actively dangerous in a spiral dive because the wing is not stalled and pulling adds 'g' at high speed. The single discriminator the student can read instantly: airspeed. Spiral = fast and increasing. Spin = slow.

Use the 3D physical model for demonstrating the spiral dive. CASA A6.6 (e,f,g): identify the nose-low unusual attitude; recover by adjusting pitch, bank and power; apply controlled corrective action within limits. The "within limits" is why the pull is smooth, not snatched — recall the rolling-'g' limit from Part 1. Memory order: Power, Bank, Pitch — throttle closed, wings level, then ease out. This is the standard nose-low unusual-attitude recovery.

Click Direct-To to arrive at Sideslipping.

CASA A5.4: sideslip aeroplane (where the flight manual permits). FIM background (Sideslipping): a sideslip is a banked attitude with the natural tendency to yaw reduced or prevented by rudder; practical applications are the sideslip into wind and the slipping turn. Note the link back to Lesson 19 (Crosswind Circuits): the wing-low crosswind technique is a sideslip held into the flare.

FIM background (Effect of controls during a sideslip): bank and apply opposite rudder; keep bank constant and hold speed with elevator; the limiting factor is usually rudder — at full rudder, further bank yaws the nose toward the lower wing. Common fault: too much rudder for the bank; and losing speed in the recovery. The interactive four-forces / physical model can help show the banked-but-not-turning attitude if useful.

CASA A5 4(c): contents of the flight manual and POH. A6 4(j): hazard of sideslip at low altitude. FIM airmanship: comply with flight manual limitations; beware fuel starvation in a prolonged sideslip with low fuel and the low-wing tank selected. This is the risk-elevated content for this waypoint. Name the hazard plainly (low-altitude sideslip, prohibited configurations) without overstating it — the manoeuvre is safe when flown within the manual's limits and at height.

Click Direct-To to arrive at the recap.

Question-list recall element — the filled summary table on the next slide is the answer key. Each question uses a Bloom's action verb and a concrete anchor.

The last row ties Part 2 back to Part 1 — the load-factor theory is the thread through every manoeuvre. TODO: consider a lesson-specific creative recap in place of, or alongside, this table — e.g. a "spot the difference" scenario where you describe an unusual attitude (airspeed high and rising, steep bank, nose low) and the student calls spiral vs spin and the recovery; or a quick "teach it back" of the sideslip control inputs using a model.