How to fly the maneuver

S-turns across a road extend the rectangular course (B) into continuous bank modulation. You fly alternating semicircles of equal radius on opposite sides of a straight ground reference, crossing it wings-level each pass. The bank changes constantly within each semicircle — same physics as the rectangular course corners, but smoothly varying rather than stepped at four discrete points.

The new skill is the road crossing. Each crossing must be exactly perpendicular to the road, wings-level, at the chosen altitude. That instant of wings-level is what the DPE evaluates first.

Setup

1. Pick a straight ground reference at least a mile long — a country road, railroad track, or section line works. Avoid roads that curve.
2. Climb or descend to 600–1,000 ft AGL (V.C.S3 anchors altitude to this value).
3. Set cruise / POH-recommended ground reference airspeed, well under VA.
4. Note wind direction before entry. Pick a road oriented roughly perpendicular to the wind, so the downwind crossing is the first leg.
5. Clear the area with a 90° clearing turn each direction. Look for traffic — you'll be heads-down on the road for a few minutes.

Entry

Enter on a heading perpendicular to the road, flying directly downwind, at the chosen altitude. You should cross the road wings-level at the moment of entry. From the crossing, immediately begin rolling into the first semicircle.

First semicircle (downwind side)

This is the steepest half-circle of the maneuver because groundspeed is highest on the tailwind portion.

1. Begin rolling into a steep bank (around 30–45°) immediately after crossing the road.
2. As the airplane turns through the downwind portion, steepen further if needed — the wind is carrying the airplane away from the road, so bank must out-turn the drift.
3. As the heading rotates back toward the road, shallow the bank progressively.
4. Plan the rate of bank reduction so the wings come back to level exactly at the road.

Road crossing

Wings level. Perpendicular to the road. Same altitude as entry. The crossing is a brief instant — don't dawdle, but don't anticipate a roll-in early either.

Second semicircle (upwind side)

This is the shallowest half-circle because groundspeed is lowest on the headwind portion.

1. Begin rolling into a shallow bank (20–30° typical) immediately after the road crossing.
2. As you turn through the upwind portion, shallow further — the wind is helping you turn, so bank must reduce or you'll cut inside.
3. As heading rotates back toward the road, deepen the bank progressively.
4. Roll out so wings come back to level exactly at the road.

Repeat and exit

Continue alternating semicircles for at least two complete S-cycles. To exit, roll out wings-level at any road crossing and climb or descend out of the maneuvering altitude.

Common pitfall. Forgetting the bank is supposed to decrease through the downwind half (and increase through the upwind half) as the heading rotates. Many students lock in a fixed bank for each semicircle and end up with unequal radii — the downwind loop bulges out, the upwind loop tightens in.