--- title: "What Happens at the Gate Before a Flight: Interactive Aircraft Turnaround | T10" url: "https://t10.net/learn/gate-turnaround/" description: "Watch a 45-minute aircraft turnaround on a model of one airport gate: the jet bridge's ground power and air, hydrant fueling, bags, catering, water and pushback, and what a late fuel cart, lightning or a no-show passenger does to the departure." lastmod: "2026-10-25" --- [Learning Center](https://t10.net/learn/)Airports and aviation # What happens at the gate before a flight In the 45 minutes between parking and pushback, a dozen crews work on one aircraft at once. The jet bridge brings power and air, fuel comes up from a pipe under the concrete, bags come off and go on, and the cabin is cleaned and catered. Watch a whole turnaround on a model of one gate, step through it, and see what a late fuel cart or a passenger who doesn't show does to the departure time. The turnaround ## Many jobs at once, on a fixed clock. An aircraft only earns money in the air, so the time at the gate is planned to the minute. Every crew has its own job and its own truck, and most of them work at the same time, on different sides of the aircraft. 1. 45 minutes ### On-block to pushback A typical turn for a narrowbody on a short flight. Airlines build a few minutes of slack into it, because something always runs a little late. 2. 19 minutes ### The longest job Boarding 168 passengers through one door, at about 9 a minute. It's usually the job that sets the departure time. 3. 7,200 liters ### Fuel for the next leg About 8 minutes through one coupling at 900 liters a minute, pumped up from a pipeline under the concrete. 4. 115 V, 400 Hz ### Power from the gate Aircraft run on 400 Hz power, not the 60 Hz in the terminal. A converter on the jet bridge makes it, so the APU in the tail can stay off. The jet bridge ## A walkway that keeps the aircraft alive. With the engines off, a parked aircraft still needs electricity for the cockpit and the galleys and air for the cabin. The jet bridge brings both from the terminal, so the aircraft doesn't have to burn fuel to make them. - Air. A heating and cooling unit under the tunnel blows conditioned air through a thick yellow hose into the belly, so the aircraft's own air conditioning can stay off. - Power. A frequency converter turns the terminal's power into 115 V at 400 Hz, through a heavy cable plugged in under the nose. - Leveling. Motorized wheels drive the cab to the door, and sensors raise and lower it as fuel, bags and passengers change the aircraft's weight. - Water. At many gates, fresh water lines run along the bridge too, so a truck isn't needed. Hydrant fueling ## The fuel comes up through the floor. At most big airports there's no tanker truck. Fuel runs from the airport's fuel farm through a pressurized pipeline under the apron to a pit, flush with the concrete, under each wing. The cart that parks beside the wing, the hydrant dispenser, has no tank. One hose goes down to the pit and another up to the coupling under the wing. In between, it filters out water and dirt, meters every liter and holds the pressure the aircraft asks for. The red diamond on its side is the placard for a flammable liquid. The critical path ## One chain of jobs sets the departure time. Most jobs wait on another one: the cleaners can't start until the passengers are off, boarding can't start until the cabin is clean and catered, the jet bridge can't pull back until the doors are shut. Follow those waits back from the pushback and you get one chain, the critical path. On an ordinary turn it runs through the cabin: engines off, chocks in, then jet bridge docks, then passengers off, then cabin cleaning, then passengers on, then doors closed, then jet bridge pulls back. Fuel, bags, water and the lavatory all have time to spare, so a few minutes lost there cost nothing. A few minutes lost on the chain go straight onto the departure time. That's also why a delay so often comes from somewhere surprising. A fuel cart that's late is harmless, until a rule says nobody boards while fuel is going in. Then fueling joins the chain, and the whole flight waits on it. ### Safety on the ramp - The beacon Red lights on top and bottom of the fuselage mean the engines are running or about to start. Nobody walks in until they're off. - Chocks and cones Chocks go in first and come out last. Cones mark the wingtips, the engines and the tail, the parts vehicles hit. - The red line Vehicles inside the red line around the aircraft move only at walking speed, and with a guide when they back up. - Lightning Lightning within about 8 km closes the ramp at many airports. The work stops; the clock doesn't. What breaks ## Six ways a turnaround goes wrong. Some problems cost nothing but fuel. Others push a job onto the critical path and the flight leaves late. Pick one to run it on the model and watch the schedule move. - ### The fuel cart is late 8 min late The hydrant dispenser is still at another gate. On its own that costs nothing, since fuel isn't on the critical path. But where fueling with passengers aboard isn't allowed, or the fire crew can't stand by, boarding has to wait until the fuel is in and the hose is off. What you'd notice: Passengers held in the gate lounge while the cabin is ready and the crew is waiting. - ### Ground power fails On time The 400 Hz unit on the jet bridge trips when it's plugged in. The flight isn't late: the aircraft's own APU, a small jet engine in the tail, keeps the lights, the avionics and the air running for the whole turn. What you'd notice: Nothing inside. Outside, the whine of the APU, and a fuel bill: it burns roughly a hundred kilograms of jet fuel an hour on the ground. - ### Lightning nearby 10 min late Lightning within about 8 km closes the ramp at many airports. Everyone outside goes in: bags, fuel, catering, the lav and water trucks all stop where they are. The jet bridge is covered, so passengers can still get off and the cleaners still work. What you'd notice: Bags and catering stop mid-job, and the jobs that need a person on the ramp all slide together. - ### A fuel spill at the pit 5 min late A coupling leaks at the hydrant pit. Fueling stops, the pit valve is closed, and the fire crew covers and cleans up the spill. Boarding is held until the area is safe. What you'd notice: Fire trucks at the gate, the fuel cart idle and a long wait at the boarding door. - ### Catering runs late 6 min late The catering truck arrives late from the kitchen. The cabin is clean, but the galley carts aren't on, and most airlines don't board until they are. What you'd notice: A ready cabin and a full gate lounge, both waiting for one truck. - ### A passenger doesn't show 4 min late A passenger checked a bag and never boarded. Security rules on many flights say a checked bag doesn't fly without its passenger, so the hold is opened again and the bag is found among the others and taken off. What you'd notice: The doors are shut, the jet bridge is ready to pull back, and nothing moves. On the model, the APU burns about 110 kg of fuel an hour while it runs on the ground, a typical figure for an aircraft this size. For airports, FBOs and ground handlers ## The turn runs on people. The paperwork doesn't have to. Regional airports, fixed-base operators and ground handling crews in New Hampshire run on small teams and tight schedules. AI won't chock a wheel, but it can take the phone, write up what happened and answer the questions that pull a lead off the ramp. - ### A delay note that writes itself An agent reads each turn's times (on-block, bags off, fuel done, doors closed), works out which job held the departure, and drafts the delay reason for the station manager to check and send. [Custom AI agents](https://t10.net/services/custom-ai-agents-model-training/) - ### The FBO line, answered Fuel orders, hangar space, a crew car at 11 at night. A phone agent takes the request, asks the right questions and texts it to whoever is on the ramp. [AI voice agents](https://t10.net/services/ai-voice-agents/) - ### Procedures the new hire can ask Ground handling manuals are long. We set up an assistant on your own procedures, so a new ramp agent can ask what comes after the chocks and get your answer, with the page it came from. [AI Cowork training](https://t10.net/services/ai-cowork-training/) [Book a free review](https://t10.net/#book) This page shows a simplified model for learning. The aircraft is a generic narrowbody twin jet sized like the A320 family, with a made-up livery, and the gate, the times and the rules are typical of many airports rather than any one airport's or airline's. Real turnarounds follow each airline's ground handling manual and each airport's own rules, which differ on things like fueling with passengers aboard and when the ramp closes for lightning. T10 isn't affiliated with any aircraft maker, airline or airport, and this is not an operations or safety manual.