Fully Developed Spin

Phases of a Spin

A spin progresses through three distinct phases, each with different aerodynamic characteristics and recovery considerations:

Phase	Duration	Characteristics
1. Incipient	Approximately 1-2 turns	Transition from stall to spin. Rotation rate, pitch attitude, and descent rate are all changing. Recovery is simplest during this phase.
2. Developed (Steady-State)	Continues until recovery action is taken	Rotation rate, airspeed, pitch attitude, and rate of descent have stabilized. The aircraft is in equilibrium — forces and moments are balanced in the spinning condition.
3. Recovery	Typically 1/4 to 1 full turn after inputs	From initiation of recovery inputs to cessation of rotation and return to unstalled flight. The aircraft transitions through a steep dive.

Autorotation Mechanics in Detail

In a fully developed spin, the aircraft rotates about a vertical (or near-vertical) axis while both wings remain stalled. The autorotation is sustained by the aerodynamic imbalance between the two wings:

The Down-Going (Inner) Wing

• Has a higher effective angle of attack due to the rotation
• Is deeply stalled — well beyond the critical angle of attack
• Produces very little lift but very high drag
• The high drag on this wing sustains the yawing moment

The Up-Going (Outer) Wing

• Has a lower effective angle of attack due to the rotation
• Is still stalled, but less deeply than the inner wing
• Produces relatively more lift and less drag than the inner wing
• The lift difference sustains the rolling moment

The combination of these asymmetric forces creates a self-sustaining rotation. The aircraft descends in a helical path around a near-vertical spin axis, with the nose pitched steeply downward (typically 60-90 degrees below the horizon depending on aircraft type).

Equilibrium in the Developed Spin

In the steady-state developed spin, the following are in equilibrium:

• Pro-spin yawing moment (from drag differential) is balanced by the anti-spin yawing moment (from the fuselage and fin acting as a weathervane)
• Pro-spin rolling moment (from lift differential) is balanced by the anti-spin rolling moment (from the aircraft's lateral stability)
• Weight is balanced by the total drag in the vertical direction — the aircraft descends at a constant rate

Spin Characteristics by Aircraft Type

Different aircraft exhibit markedly different spin characteristics based on their design:

Design Factor	Effect on Spin
Wing position (high vs low)	High-wing aircraft tend to have a flatter spin attitude; low-wing aircraft tend to have a steeper nose-down attitude
Tail configuration	T-tail aircraft may have the elevator blanketed by the wing wake in a spin, making recovery more difficult
Mass distribution	Aircraft with mass concentrated in the wings (fuel) tend to spin flatter and may be more resistant to recovery
CG position	Aft CG makes spin entry easier and recovery more difficult. Forward CG provides more resistance to spinning.

Height Loss During Spins

A fully developed spin results in significant altitude loss with each turn. Typical values for light training aircraft:

• Incipient phase: 300-500 feet lost during the first 1-2 turns
• Developed spin: 500+ feet per turn (varies by aircraft type)
• Recovery phase: Additional 500-1,000 feet lost during recovery from the dive

A spin of just 3 turns could easily result in a total altitude loss of 2,000-3,000 feet from entry to return to level flight. This underscores why an inadvertent spin at traffic pattern altitude (800-1,000 feet AGL) is typically unrecoverable.

Aircraft Certification for Spins

Not all aircraft are approved for intentional spins. FAA certification categories determine what maneuvers are permitted:

Category	Spin Approval	Notes
Normal	NOT approved for spins	Must demonstrate recovery from a one-turn spin or one 3-second spin during certification, but intentional spins are prohibited in service
Utility	May be approved for spins	Check the POH/AFM — spin approval depends on weight, CG, and configuration. Often approved only at reduced weight.
Aerobatic	Approved for spins	Tested for at least 6 turns of a spin. No specific limitations beyond POH/AFM restrictions.

Purpose

To enter and recover from a fully developed spin using the standard PARE recovery procedure, and to develop the ability to count turns and maintain orientation during the spin.

Airmanship

Pre-Spin Checks

Complete a full HASELL check before any spin exercise. For fully developed spins, the altitude requirement is higher than for incipient spin practice:

• Minimum entry altitude: As specified by your instructor — typically no lower than 5,000 feet AGL to allow for multiple turns plus recovery altitude
• Minimum recovery altitude: Typically 3,000 feet AGL — recovery must be initiated by this altitude regardless of the planned number of turns
• Configuration: Clean (flaps up, gear up if retractable)
• Weight and CG: Confirm within the approved envelope for spinning

Full Spin Entry

The spin is entered using the same technique as for the incipient spin, but the pro-spin inputs are maintained to allow the spin to develop fully:

1. Complete HASELL checks. Note the entry altitude and a reference heading.
2. Reduce power to idle.
3. Raise the nose to maintain altitude as airspeed decreases.
4. At the full stall (buffet, stick shaker, or full back pressure with wing drop), apply full rudder in the desired spin direction.
5. Maintain full back pressure on the control column and full rudder — these pro-spin inputs sustain the spin.
6. The spin will transition from incipient to fully developed over 1-2 turns.

Counting Turns

Maintaining orientation during a spin requires practice. Use the following technique to count turns:

• Before entry, select a prominent reference point on the horizon (a landmark, road, or compass heading).
• Each time the nose passes through this reference point, one full turn has been completed.
• Count aloud: "One... two... three..." as each turn is completed.
• The turn coordinator will show full deflection in the direction of the spin — it is not useful for counting turns.

PARE Recovery Procedure

The standard spin recovery procedure is remembered by the mnemonic PARE:

Step	Action	Detail
P	Power — idle	Reduce power to idle (if not already). Power can flatten the spin and make recovery more difficult.
A	Ailerons — neutral	Ensure ailerons are neutral. Aileron input during a spin can be counterproductive or deepen the spin depending on aircraft type.
R	Rudder — full opposite	Apply full rudder opposite to the direction of spin. This opposes the yaw and disrupts the autorotation balance.
E	Elevator — forward	Move the control column briskly forward (toward neutral or beyond) to reduce the angle of attack and break the stall. The rotation should stop within one turn.

After Rotation Stops

1. Centralize the rudder — once rotation ceases, neutralize the rudder to prevent entering a spin in the opposite direction.
2. Level the wings — use coordinated controls to roll wings level.
3. Recover from the dive — smoothly apply back pressure. Do not pull abruptly — the airspeed will be increasing rapidly in the dive and excessive G-loading could overstress the aircraft.
4. Apply power — as the nose reaches the horizon and the aircraft returns to level flight, smoothly apply power.

Recovery from Various Attitudes

Your instructor may demonstrate spin entries and recoveries from different initial conditions to show that the PARE procedure remains effective regardless of the entry situation:

• Spin to the left: Full right rudder for recovery
• Spin to the right: Full left rudder for recovery
• Spin from a turning stall: The spin direction may not match the original turn direction — always identify the actual direction of rotation before applying recovery inputs

Key Takeaways

Spin Phases

Phase	Key Feature	Recovery Difficulty
Incipient	Transition — rotation accelerating	Easiest — least altitude loss
Developed	Steady-state — constant rotation rate	More altitude required
Recovery	From inputs to cessation of rotation	Additional altitude for dive pullout

PARE Recovery Procedure

Letter	Action
P	Power idle
A	Ailerons neutral
R	Rudder full opposite to spin direction
E	Elevator forward to break the stall

Critical Points to Remember

• Spin avoidance remains the primary strategy — understanding the fully developed spin reinforces why prevention is paramount.
• Most aircraft are NOT approved for intentional spins — normal category aircraft are prohibited from intentional spinning. Always check the POH/AFM.
• Height loss is severe — 500+ feet per turn in the developed spin, plus additional altitude for the dive recovery. Total loss can easily exceed 2,000 feet.
• CG position is critical — an aft CG makes spin recovery more difficult or potentially impossible. Never fly outside the approved CG envelope.
• The PARE procedure works — when applied correctly, this standard technique will recover the aircraft from a developed spin in most approved aircraft.
• Do not use aileron during recovery — ailerons neutral is a deliberate and important step in the PARE procedure.

Spin Avoidance — The Complete Picture

Having completed both the spin avoidance (Exercise 11a) and fully developed spin (Exercise 11b) lessons, you now understand the complete progression from coordinated flight through stall, incipient spin, and fully developed spin. Your primary defenses are:

1. Maintain coordination — ball centered at all times, especially at low speed
2. Maintain adequate airspeed — respect the stall speed in all configurations
3. Recognize the incipient spin early — if prevention fails, early recognition minimizes altitude loss
4. Apply the correct recovery immediately — opposite rudder, forward elevator, recover from dive

What's Next

You are now progressing to Stage 3 of your PPL training. The skills learned in Stages 1 and 2 — aircraft handling, stall recognition, and spin avoidance — form the foundation for the navigation, cross-country, and advanced maneuvers that follow.

Skills You'll Work On

These are the maneuvers and procedures covered in this lesson. Your instructor tracks each one as you progress.

• Preflight Inspection
• Engine Starting
• Taxi & Before Takeoff Check
• Radio Communications
• Normal Takeoff and Climbs
• General Handling
• Slow Flight (With & Without Flaps)
• Steep Turns
• Use of Trim Flaps Mixture Carb Heat
• Power On Stall
• Power Off Stalls
• Side Slip Technique (At Altitude)
• Go Around Procedure
• Ground Ref Maneuvers
• Approach Planning & Altimeter Setting
• Normal/ Crosswind Landing
• After Landing Parking and Securing

Grades reflect what was covered in this lesson, not a certification of pilot competency.

Lesson Plan

Where this fits: Exercise 11b, "Fully Developed Spin," closes the stall-and-spin sequence by exploring what happens when a spin is allowed to develop fully. It deepens the case for spin avoidance and precedes the circuit work that begins with takeoff to downwind. Conducted on Aviator.NYC's FAA-approved Advanced Aviation Training Device (AATD), which is not bound by the aircraft spin-certification limits noted in the POH/AFM.

Prerequisite

Student can recognize an incipient spin and recover promptly, and understands the stall-plus-yaw cause of autorotation.

Materials

C172 G1000 AATD simulator; checklist card; HASELL check reference; local VFR sectional and airport diagram.

Objectives for this session

Describe the phases of a fully developed spin (entry, incipient, developed, recovery) and how autorotation makes the spin self-sustaining.

Enter a fully developed spin, count turns, and maintain orientation, recognizing the considerable height loss involved.

Apply the standard PARE recovery procedure (Power idle, Ailerons neutral, Rudder opposite, Elevator forward) to exit from various spin attitudes.

Looking Ahead

Next is Lesson 11, Takeoff and Climb to Downwind (Exercise 12), which begins circuit flying and applies the slow-flight and stall-awareness skills near the ground. If the order of the PARE inputs or counting turns was unclear today, walk through a recovery once more at the start of Lesson 11 before moving to the pattern.