You're coming into YVR from Toronto. It’s been a long flight but it’s on schedule. Smooth ride, decent movie. But then the plane thumps and rattles onto the runway and you’re thinking: man, where’d this rookie learn to fly?
It’s common, this reaction. Not universal, though. In Italy, they applaud every landing provided the head count is the same as on departure. But in North America, assuming the wing wasn’t on fire during descent, either a pilot greases the touchdown or we all roll our eyes and think of how we once flew a 737 clean under the Golden Gate Bridge in MS Flight Simulator before (admittedly) crashing into the Palace of Fine Arts.
It’s ironic, given we basically haven’t any clue what’s going on during landing outside that millisecond the gear makes contact. The fact is, a pilot has to get a whole lot right before the privilege of bumping onto the runway is even available.
John Morris, president of Blackcomb Aviation, runs a fleet of jet and turboprop aircraft and helicopters into Vancouver. He explains that landing at YVR starts 40 minutes and 100 nautical miles back. At “top of descent,” the pilot checks local weather, visibility, ceiling, and winds. Here, the aircraft is directed onto a Standard Terminal Arrival Route (STAR), a sequence of waypoints and tracks that takes the plane into the airport area. STARs are programmed into the flight computer, but pilots also keep a book of them for doing it the old-fashioned way if necessary.
PROJECT RUNWAY How to Land a Plane in
STARs into the YVR area have names like GRIZZ3 and SHARK7, and an aircraft is assigned one based on the direction it’s arriving from. The assignment comes not from the YVR tower but from Vancouver Approach Control, a windowless room in a building in Surrey where up to 40 staff, including air-traffic controllers and support personnel, coordinate flights arriving at and departing from the YVR area. The idea is to deliver all incoming flights in a nicely spaced fashion to the airport flight pattern, the last set of tracks around the airport that planes follow before landing.The STARs are actually flown either manually or by crew-supervised autopilot, based on pilot preference and weather. The worse the conditions, the more likely the pilot will make use of available automation during the descent. But in either case, as Morris summarizes: “You basically plan an idle-power descent and glide the airplane down the flight path.”
Following the STAR delivers the plane to the flight pattern at the top of the downwind leg, which runs parallel to the runway about five miles south of the airport at 3,000 feet. At this point, the crew begins to follow a series of radar vectors from Surrey, each one consisting of a compass direction, a speed, and an altitude. The first vector guides the plane 12 nautical miles down the downwind leg, still at about 3,000 feet. The plane is now about 10 miles past the airport and must turn around to begin its final approach. Surrey provides the radar vectors to complete this 180-degree turn, after which point the plane is at the top of final approach.
Depending on wind, you’re over either the Georgia Strait or Delta here. That is, you’re either headed in from the ocean toward Runway 08 Left or 08 Right (named for the 081 degree bearing of the tarmacs, looking east), or you’re over Delta aimed at 26 Left or 26 Right (since the runways bear 261 degrees looking in this direction).
At this point, Morris says, the crew would hear the aircraft ID followed by something like: “Turn right heading 050, you’re cleared for the ILS Runway 08 Right Vancouver. Number 2 to a Boeing 737 four miles ahead. Contact the tower now, 18-7.” The last part is a reference to YVR tower frequency 118.7 MHz.
Note that the YVR tower is now in the picture. Also that your flight has been delivered onto the Instrument Landing System (ILS), a set of two radio waves that the pilot follows down to the runway. The ILS display in the cockpit shows a localizer, which indicates whether the aircraft is on course to hit the centre of the runway laterally, and a glide slope of about three degrees that indicates whether the aircraft is on track vertically to touch down at the near end of the runway. These form crosshairs on the landing instruments.
So far, speed and altitude have been controlled with power and pitch adjustments, as well as the steady deployment of flaps (and their leading-edge counterparts, called slats). Once established on the localizer and glide slope, the airplane is “stabilized,” meaning flaps and slats are in their final configuration and gear is extended. At this point, your speed is about 160 knots. “So you’re monitoring instruments,” Morris says. “But also watching for wind shear, and if you are visual, monitoring traffic, birds, and anything else that could interfere with your approach.” As for birds, he points out that engines on commercial jets are tested by firing frozen birds through them, so they’re more robust than you might think. But he nonetheless cautions: “They are a hazard you want to do your best to avoid,” pointing to the havoc a flock wreaked on US Airways 1549 earlier this year.
As they descend toward the tarmac, all aircraft reach a “decision height,” an altitude/visibility limitation at which pilots must have the necessary visual reference points to land. Otherwise he must execute a go-around. The decision height ranges from 200 feet altitude and 2,600 feet visibility (for a Category 1 aircraft like the Citation Sovereign that Morris flies) down to zero/zero for a Category 3C airliner like an Airbus 340, which can land on autopilot in conditions of literally zero ceiling and visibility. Robo-plane.
Just before touchdown, at about 130 knots and 50 feet up, the pilot removes remaining power and “flares” the aircraft by easing back on the yoke. At touchdown, the yoke is returned to neutral to settle the nose wheel, and the pilot applies brakes, spoilers, and reverse thrust, tracking the centre of the runway.
And if it thumped? Well, going forward, consider being Italian and applauding anyway, since bump factors are sometimes out of the pilot’s hands. Wet runways usually make for smoother landings. Light and steady winds are a bonus. Gusty winds: a little more work.
“But bear in mind,” Morris says, “a nice smooth landing 5,000 feet down a 10,000 foot runway is not a good landing.”