Track within 3 nm, timing checks

This is the element the examiner grades with a stopwatch and a ruler. Everything in Task A converges here, into four numbers.

The ACS standards, verbatim

The examiner checks three skill items against fixed tolerances:

• S5 — "Verify position within three nautical miles of the flight-planned route."
• S6 — "Arrive at the en route checkpoints within five minutes of the initial or revised ETA, and provide a destination estimate."
• S7 — "Maintain the selected altitude, ±200 feet and heading, ±15°."

Four numbers to know cold: 3 NM, 5 minutes, ±200 ft, ±15°.

Running the checks in flight

Timing and groundspeed. Start a clock over a checkpoint, stop it over the next. GS = distance ÷ time. Worked example: your first two checkpoints are 20 NM apart and you planned 11 minutes (≈109 kt). You actually cross the second at 12.5 minutes, so GS = 20 ÷ (12.5 ÷ 60) ≈ 96 kt — slower than planned. Apply 96 kt to the remaining distance and every ETA slides later; update them now, not at the destination.

The destination estimate isn't optional. S6 wants you to do that same division for the whole remaining route and give the examiner a time: "At current groundspeed, destination in 34 minutes — 1112 local." The phrase "initial or revised" is the whole point: the examiner wants to see you update the ETA from actual groundspeed, then hold yourself to the revised number within five minutes.

Hold altitude and heading while you compute. The ±200/±15 tolerance is the easiest part to bust, because it goes out the window the moment you drop your head to the E6B. Trim first, then do the math — and glance outside between figures.

Every checkpoint is also a fuel check: compare fuel remaining against the fuel you planned to that point. A groundspeed running slow means you'll burn more than planned to the destination, so the timing check and the fuel check are really the same glance at the panel.

Choosing a legal altitude

"Maintain the selected altitude" assumes you picked a legal one. Above 3,000 ft AGL in cruise, VFR uses the hemispheric rule (§91.159): on a magnetic course of 0–179° fly odd thousands + 500 ft (5,500, 7,500…); on 180–359° fly even thousands + 500 ft (4,500, 6,500…). Choose the altitude that fits the rule, the terrain (the MEF from K3), the winds, and your cloud clearances — then hold it within ±200 ft.

A pilot who never revises the ETA and lands twelve minutes off fails S6 — even if the original plan was perfectly reasonable. The standard rewards updating, not just planning.