phpvms/app/Database/factories/FlightFactory.php

<?php
/**
 * Create flights
 */
use Faker\Generator as Faker;

$factory->define(App\Models\Flight::class, function (Faker $faker) {
    return [
        'id'         => $faker->unique()->numberBetween(10, 10000000),
        'airline_id' => function () {
            return factory(App\Models\Airline::class)->create()->id;
        },
        'flight_number'  => $faker->unique()->numberBetween(10, 1000000),
        'route_code'     => $faker->randomElement(['', $faker->text(5)]),
        'route_leg'      => $faker->randomElement(['', $faker->numberBetween(0, 1000)]),
        'dpt_airport_id' => function () {
            return factory(App\Models\Airport::class)->create()->id;
        },
        'arr_airport_id' => function () {
            return factory(App\Models\Airport::class)->create()->id;
        },
        'alt_airport_id' => function () {
            return factory(App\Models\Airport::class)->create()->id;
        },
        'distance'    => $faker->numberBetween(0, 1000),
        'route'       => null,
        'level'       => 0,
        'dpt_time'    => $faker->time(),
        'arr_time'    => $faker->time(),
        'flight_time' => $faker->numberBetween(60, 360),
        'has_bid'     => false,
        'active'      => true,
        'visible'     => true,
        'days'        => 0,
        'start_date'  => null,
        'end_date'    => null,
        'created_at'  => $faker->dateTimeBetween('-1 week', 'now'),
        'updated_at'  => static function (array $flight) {
            return $flight['created_at'];
        },
    ];
});