Common errors

Forward slip errors split into two families: mistimed entries and recoveries (when to start, when to stop) and input-coordination errors (the bank-and-rudder relationship). The six below cover the common faults.

1. Insufficient rudder for the bank

What it looks like: the airplane banks but the nose still tracks roughly down the centerline — only a tiny ground-track offset. The descent rate barely increases.

Why: the pilot established bank but didn't apply enough opposite rudder. The airplane is lightly cross-controlled; drag is barely increased.

Fix: commit to the rudder. The rudder input should be visibly opposite the bank — full or near-full rudder for a noticeable slip. If the rudder feels light, push more.

2. Excessive bank with insufficient rudder → turning slip

What it looks like: the airplane banks deeply but the rudder isn't strong enough to hold the heading offset. The airplane turns instead of slipping — drifts off the centerline.

Why: treating the slip as a banked descent without enough opposite rudder.

Fix: rudder leads, bank follows. Apply opposite rudder to set the heading offset first; add bank to match. The two are sized to each other — more rudder = more bank possible without turning.

3. Pitch wandering during the slip

What it looks like: during the slip, the pitch attitude oscillates — sometimes nose-down, sometimes nose-up. Descent rate varies; airspeed (where readable) varies too.

Why: the pilot is busy with bank and rudder and forgot the elevator. Pitch attitude isn't a primary control input during the slip — it's set and held.

Fix: trim before entering the slip. Set the pitch attitude with elevator; trim for hands-off; then enter the slip. The slip is bank-and-rudder; pitch is already handled.

4. Late recovery (slipping into the round-out)

What it looks like: the airplane is still cross-controlled at 100 ft AGL. The round-out happens with residual rudder or bank, leading to asymmetric flare and potential drift on touchdown.

Why: the pilot kept slipping to "use up" excess altitude and ran out of altitude to recover normally.

Fix: recover by 300–500 ft AGL at the latest. If still high at 500 ft, go around (H) — don't try to slip into the round-out. The maneuver doesn't end at touchdown; it ends well before.

5. Recovery sequence wrong (rudder last)

What it looks like: the pilot rolls out of the bank first, then releases the rudder. The airplane briefly skids (rudder-only with no bank) during the moment between roll-out and rudder release.

Why: the pilot treats the slip as "bank + rudder" and removes them in arbitrary order.

Fix: release the rudder first, then roll out. The rudder is the cross-control input; releasing it allows the airplane to re-coordinate naturally. The bank then comes out smoothly with no skid transient.

6. Trying to slip with flaps when POH forbids it

What it looks like: the airplane enters a slip with full flaps in a configuration the POH limits, and exhibits unusual pitch behavior (some airplanes pitch up sharply when slipping with flaps because of disturbed tail airflow).

Why: the pilot didn't check the POH or assumed slipping is always OK.

Fix: check the POH before training. If flap-extended slips are prohibited or limited, slip with the allowed flap setting only. Reduce flap before entering the slip if needed.

How errors compound. Inputs (#1, #2) and pitch (#3) all share a common cause — the pilot is overwhelmed by simultaneous bank, rudder, and pitch demands. The fix is trim and set pitch before entering the slip, then the slip becomes pure bank-and-rudder. Recovery errors (#4, #5) reinforce each other — late and out-of-order recovery is the dangerous pair. The discipline: always recover the slip, then make the landing decision. If you can't recover by 500 ft AGL, the decision is go around (H), not "salvage with a deep slip."