{
  "response": {
    "Key": "IAD-LHR",
    "orig": {
      "code": "IAD",
      "type": "airport",
      "city": "Washington",
      "fullCity": "Washington, United States",
      "airport": "Washington Intl Airport"
    },
    "dest": {
      "code": "LHR",
      "type": "airport",
      "city": "London",
      "fullCity": "London, England",
      "airport": "Heathrow Airport"
    },
    "faq": {
      "q0": {
        "question": "What is the typical flight duration from Washington to London?",
        "answer": "Flights from Washington Dulles to London Heathrow cover about 3,670 miles and typically take 7 hours 25 minutes eastbound, while the return leg averages 8 hours 25 minutes — about an hour longer due to prevailing headwinds.",
        "methodology": "Flight times and distances come from our flight-schedule database, which combines published airline timetables, U.S. government schedule data from the Bureau of Transportation Statistics (BTS), and observed flight operations from the EUROCONTROL/OpenSky Open Performance Data Initiative (OPDI). The typical flight time is the median scheduled block time across all carriers on the route, computed the same way in both directions so the difference reflects prevailing winds rather than any change in method. Distance is the great-circle distance between the two airports, so the actual flown track is typically 2-5% longer.",
        "toolsUsed": [
          "flight_schedule"
        ]
      },
      "q1": {
        "question": "Are there any direct flights from Washington to London?",
        "answer": "Washington Dulles to London Heathrow has plentiful nonstop service, with United, British Airways, and Virgin Atlantic all flying the route daily and combining for roughly 142 weekly nonstop flights. United leads with up to 9 departures a day, British Airways runs about 7, and Virgin Atlantic adds about 4, all operating seven days a week. Flights take roughly 7 hours and 25 minutes eastbound.",
        "methodology": "Airlines and weekly frequencies are compiled from our flight-schedule database, which combines published airline timetables, U.S. government schedule data from the Bureau of Transportation Statistics (BTS), and observed flight operations from the EUROCONTROL/OpenSky Open Performance Data Initiative (OPDI). We count each operating carrier's scheduled weekly departures and the days it flies; where there is no nonstop service, connecting carriers are identified by linking scheduled nonstop segments through common hub airports. Where a median fare is shown for a carrier, it reflects the real fares Priceline users found on this route in the last 72 hours. Carrier service, flight times and distances for this route come from our flight-schedule database, which draws on published airline timetables, U.S. government schedule data, and observed operations from the EUROCONTROL/OpenSky Open Performance Data Initiative (OPDI). We report the days of the week and the departure times each carrier operates. The typical flight time is the median scheduled block time, given both per carrier and across all carriers on the route; where a schedule does not publish an elapsed time, it is derived from the scheduled departure and arrival times converted to UTC. Outbound and return times are computed by the same method, so the difference between them is directly comparable and reflects prevailing winds rather than any change in derivation. Distance is the great-circle distance between the two specific airports named, so an actual flown track is typically 2-5% longer. Where an aircraft type is shown, it also comes from this database: for U.S. routes it is grounded in the tail number that actually operated the flight, and elsewhere in the airline's filed equipment code. Where the source does not commit to a specific variant we name the aircraft family (for example \"Airbus A320 family\") rather than guess a member, and where no reliable type is on file the aircraft is simply omitted rather than estimated. Flights known only from the OPDI feed carry no aircraft type, because their flight numbers are synthetic and joining by flight number would attribute another flight's aircraft. Where shown, on-time departure and arrival rates and cancellation rates come from the U.S. Bureau of Transportation Statistics (BTS) Airline On-Time Performance dataset, which covers U.S. domestic routes only; where a typical fare is shown, it comes from the U.S. DOT Airline Origin and Destination Survey (DB1B), a quarterly 10% sample of tickets sold.",
        "toolsUsed": [
          "route_airlines",
          "flight_schedule"
        ]
      },
      "q2": {
        "question": "Are there visa requirements to travel from Washington to London?",
        "answer": "For United States citizens travelling from Washington to London, a visa is not required for a short tourist visit; entry is visa-free and the maximum permitted stay is 6 months. However, an electronic travel authorisation (ETA) must be obtained before travel. This applies to United States nationality specifically.\n\nThis is general guidance to help you plan, not official immigration advice — entry rules can change and can depend on your nationality and circumstances, so please confirm the current requirements with the relevant embassy or official government source before you travel.",
        "toolsUsed": [
          "article_lookup"
        ],
        "references": [
          {
            "url": "https://en.wikipedia.org/wiki/Visa_policy_of_the_United_Kingdom",
            "title": "Visa policy of the United Kingdom",
            "favicon": "https://en.wikipedia.org/static/favicon/wikipedia.ico"
          },
          {
            "url": "https://www.gov.uk/entering-staying-uk",
            "title": "Entering and staying in the UK - GOV.UK",
            "favicon": "https://www.gov.uk/favicon.ico"
          }
        ],
        "preopenedReferences": true,
        "stageOnly": true
      },
      "q3": {
        "question": "What are the ground transportation options in London?",
        "answer": "From Heathrow, the fastest option to central London is the Heathrow Express, reaching Paddington in just 15 minutes for £10+ when booked in advance. The London Underground (Piccadilly line) is the cheapest and most-used route, taking under an hour for £5.50 with trains every 10 minutes. The Elizabeth line offers a newer alternative at £13.90 and under 45 minutes, while coaches to Victoria start at £10. Taxis and black cabs take at least an hour and are the most expensive, and car rentals are available but incur congestion and ULEZ charges.",
        "toolsUsed": [
          "article_lookup"
        ],
        "references": [
          {
            "url": "https://www.heathrow.com/transport-and-directions/getting-to-central-london",
            "title": "Getting to Central London | Heathrow",
            "favicon": "https://www.heathrow.com/etc.clientlibs/heathrow/clientlibs/vanilla-components/base/resources/favicon-57x57.png"
          },
          {
            "url": "https://www.heathrow.com/transport-and-directions",
            "title": "Transport and directions | Heathrow",
            "favicon": "https://www.heathrow.com/etc.clientlibs/heathrow/clientlibs/vanilla-components/base/resources/favicon-57x57.png"
          },
          {
            "url": "https://en.wikipedia.org/wiki/Heathrow_Central_bus_station",
            "title": "Heathrow Central bus station",
            "favicon": "https://en.wikipedia.org/static/apple-touch/wikipedia.png",
            "time_published": "2026-08-24T02:58:47Z"
          },
          {
            "url": "https://heathrow.com/de/transport-and-directions/getting-to-central-london",
            "title": "Anreise in die Londoner Innenstadt (Central London) | Heathrow",
            "favicon": "https://www.heathrow.com/etc.clientlibs/heathrow/clientlibs/vanilla-components/base/resources/favicon-57x57.png"
          },
          {
            "url": "https://www.heathrow.com/fr/transport-and-directions/getting-to-central-london",
            "title": "Se rendre au centre de Londres | Heathrow",
            "favicon": "https://www.heathrow.com/etc.clientlibs/heathrow/clientlibs/vanilla-components/base/resources/favicon-57x57.png"
          }
        ]
      },
      "q4": {
        "question": "When is the cheapest time to fly from Washington to London?",
        "answer": "Average fares from Washington to London bottom out around $323 in late September, the cheapest stretch of the year. The cheapest months overall are September ($333), October ($338), and February ($356), while late December is the priciest period at $450 on average. December as a whole averages $425, followed by July at $412 and June at $398.",
        "methodology": "Seasonal fares come from Priceline's own air booking-summary archive, analysed in-house and refreshed monthly. For each day of the year we take a representative round-trip fare, a blend of the 25th-percentile and average ticket price over the route's bookings, and smooth the series into a seasonal curve; the half-month low and high and the monthly figures quoted here are averages of that curve. Thin and international routes borrow their seasonal shape from the nearest busy routes, with the price level anchored to the route's own bookings.",
        "toolsUsed": [
          "seasonal_prices"
        ]
      },
      "q5": {
        "question": "How far in advance should I book tickets from Washington to London?",
        "answer": "For flights from Washington to London, the optimal booking window is 4-6 weeks before departure, when fares average around $339. Booking around 30 days out tends to yield the lowest prices, while fares climb steadily if you book more than about 10 weeks ahead. For summer or holiday periods, demand is higher, so you'll generally want to book toward the earlier side of that window or even a bit further out to secure better fares.",
        "methodology": "Booking-window guidance comes from the same monthly in-house analysis of Priceline's own air booking-summary archive. We aggregate the route's bookings by how many days before departure they were made, from about 180 days out to the day of travel, smooth the curve, and highlight the stretch of lead times with the lowest average fare. Thin and international routes borrow the curve shape from the nearest busy routes, anchored to the route's own price level. It reflects current fares and is refreshed monthly.",
        "toolsUsed": [
          "booking_timing"
        ]
      },
      "q6": {
        "question": "Are overnight (red‑eye) flights available from Washington to London?",
        "answer": "Overnight red‑eye flights are available nonstop from Washington Dulles to London Heathrow. United, Virgin Atlantic, and British Airways all operate daily red‑eyes, with departures typically between 9:30 PM and 11:30 PM. These flights land at Heathrow in the early morning hours — arrival times cluster around 6:00–7:00 AM local time the next day.",
        "methodology": "Red-eye flights are identified from scheduled local departure and arrival times in our flight-schedule database — built from published airline timetables and official schedule data, including U.S. Department of Transportation records for domestic routes — flagging services that depart late at night and arrive the following morning; for connecting itineraries the red-eye is based on the timing of the overnight long-haul leg.",
        "toolsUsed": [
          "redeye_flights"
        ]
      },
      "q7": {
        "question": "Which airlines usually operate this route from Washington to London?",
        "answer": "United Airlines, British Airways, and Virgin Atlantic operate non‑stop from Washington Dulles to London Heathrow. United offers 63 weekly flights with a median fare around $1,092, British Airways has 52 weekly flights around $975, and Virgin Atlantic runs 27 weekly flights. All three carriers operate daily service with multiple departure times throughout the evening.",
        "methodology": "Airlines and weekly frequencies come from our flight-schedule database, which combines published airline timetables, U.S. government schedule data from the Bureau of Transportation Statistics (BTS), and observed flight operations from the EUROCONTROL/OpenSky Open Performance Data Initiative (OPDI). We count each operating carrier's scheduled weekly departures and the days it flies; where there is no nonstop service, connecting carriers are identified by linking scheduled nonstop segments through common hub airports. Where a typical fare is shown for a carrier, it is the median of the real fares Priceline users found on this route in the last 72 hours.",
        "toolsUsed": [
          "route_airlines"
        ]
      },
      "q8": {
        "question": "If I need a connection, what are common layover cities between Washington and London?",
        "answer": "Common layover cities include Reykjavik, Dublin, Amsterdam, and Paris. Reykjavik and Dublin offer US preclearance on return and efficient transfers. Amsterdam and Paris provide broad onward connections and single-terminal operations. Transit is visa‑free for eligible passengers."
      },
      "q10": {
        "question": "Which months have the best weather for traveling to London?",
        "answer": "May to early June and September offer pleasant temperatures, blooming parks, and fewer tourists than July and August."
      },
      "q11": {
        "question": "What documents should I bring with me to the airport when flying from Washington to London?",
        "answer": "Bring a passport valid for at least six months, any required UK ETA or visa, proof of onward or return travel, a payment method for baggage and any necessary vaccination or insurance documents."
      },
      "q12": {
        "question": "Which airport should I use in London?",
        "answer": "Heathrow is the primary hub for international flights and offers the widest range of connections. Gatwick serves low-cost and leisure carriers, while City Airport is closest to central London and convenient for business travel."
      },
      "q13": {
        "question": "How do I get to Washington Intl Airport from the city center?",
        "answer": "From downtown Washington, the most popular and often fastest option is the Metrorail Silver Line, which connects directly to Dulles via an indoor pedestrian tunnel with moving sidewalks. Ride-share services like Uber and Lyft, as well as taxis, offer door-to-door convenience at a higher cost, while shared shuttle vans are a middle-ground option. Driving yourself is possible with on-site parking garages, though it's typically the most expensive and time-consuming choice when factoring in traffic and parking fees.",
        "toolsUsed": [
          "article_lookup"
        ],
        "references": [
          {
            "url": "https://www.flydulles.com/parking-transportation",
            "title": "flydulles.com - Parking & Transportation",
            "favicon": "https://www.flydulles.com/themes/custom/mwaa_barrio/favicon.ico"
          },
          {
            "url": "https://www.flydulles.com/metro",
            "title": "flydulles.com - Dulles Airport Metrorail Station",
            "favicon": "https://www.flydulles.com/themes/custom/mwaa_barrio/favicon.ico"
          },
          {
            "url": "https://www.flydulles.com/",
            "title": "Official Website of Washington Dulles International Airport - IAD",
            "favicon": "https://www.flydulles.com/themes/custom/mwaa_barrio/favicon.ico"
          },
          {
            "url": "https://en.wikipedia.org/wiki/Dulles_International_Airport",
            "title": "Dulles International Airport",
            "favicon": "https://en.wikipedia.org/static/apple-touch/wikipedia.png",
            "time_published": "2026-09-18T13:47:09Z"
          },
          {
            "url": "https://flydulles.com/shopping-dining",
            "title": "flydulles.com - Shopping & Dining",
            "favicon": "https://flydulles.com/themes/custom/mwaa_barrio/favicon.ico"
          }
        ]
      },
      "q14": {
        "question": "Are there hotels or sleeping facilities at London airport?",
        "answer": "London Heathrow has several on-site and terminal-connected hotels. The Sofitel London Heathrow is directly connected to Terminal 5, the Hilton Garden Inn is connected to Terminals 2 and 3, and the Aerotel London Heathrow is located landside in Terminal 3 Arrivals. Hotels connected to Terminal 4 include the Hilton London Heathrow Airport, Premier Inn, Holiday Inn Express, and Crowne Plaza London Heathrow.",
        "toolsUsed": [
          "article_lookup"
        ],
        "references": [
          {
            "url": "https://sleepinginairports.net/guides/london-heathrow-airport-guide.htm",
            "title": "London Heathrow Airport Guide (LHR) - Sleeping in Airports",
            "favicon": "https://www.sleepinginairports.net/nitropack_static/oBWrHkPujHTPIaVWqdDSDhClXUyrYhhb/assets/images/optimized/rev-b853180/www.sleepinginairports.net/wp-content/uploads/2018/09/cropped-sia-logo-180x180.png",
            "time_published": "2018-10-02T00:00:37Z"
          },
          {
            "url": "https://sofitel.accor.com/en/hotels/6214/offers/Park-Sleep-and-Fly.html",
            "title": "Park, Sleep & Fly | Hotel Offer | Sofitel London Heathrow",
            "favicon": "https://sofitel.accor.com/content/dam/technical-folder/seo/sofitel/apple-touch-icon.png"
          },
          {
            "url": "https://www.sleepinginairports.net/europe/londonheathrow.htm",
            "title": "London Heathrow Airport Guide (LHR) - Sleeping in Airports",
            "time_published": "2026-01-15T21:00:59Z"
          }
        ]
      },
      "q15": {
        "question": "Are there currency exchange offices, prayer rooms and Wi‑Fi at Heathrow Airport?",
        "answer": "Heathrow Airport offers free Wi-Fi throughout all terminals, with no payment needed to connect and browse. Currency exchange services are available across Heathrow's terminals, alongside cash machines. Prayer rooms and chapels are also provided at the airport for passengers seeking a quiet space for worship or reflection.",
        "toolsUsed": [
          "article_lookup"
        ],
        "references": [
          {
            "url": "https://heathrow.com/at-the-airport/terminal-guides",
            "title": "Terminal guides | Heathrow",
            "favicon": "https://www.heathrow.com/etc.clientlibs/heathrow/clientlibs/vanilla-components/base/resources/favicon-57x57.png"
          },
          {
            "url": "https://www.heathrow.com/at-the-airport/terminal-guides/terminal-5-guide",
            "title": "Heathrow Terminal 5 Information | Heathrow",
            "favicon": "https://www.heathrow.com/etc.clientlibs/heathrow/clientlibs/vanilla-components/base/resources/favicon-57x57.png"
          },
          {
            "url": "https://www.heathrow.com/at-the-airport",
            "title": "At the airport | Heathrow",
            "favicon": "https://www.heathrow.com/etc.clientlibs/heathrow/clientlibs/vanilla-components/base/resources/favicon-57x57.png"
          },
          {
            "url": "https://www.heathrow.com/at-the-airport/airport-services",
            "title": "Airport services | Heathrow",
            "favicon": "https://www.heathrow.com/etc.clientlibs/heathrow/clientlibs/vanilla-components/base/resources/favicon-57x57.png"
          },
          {
            "url": "https://heathrow.com/passenger-updates",
            "title": "Passenger updates | Heathrow",
            "favicon": "https://www.heathrow.com/etc.clientlibs/heathrow/clientlibs/vanilla-components/base/resources/favicon-57x57.png"
          }
        ]
      },
      "q16": {
        "question": "Are there accessible services or children's facilities at the Washington and London airports?",
        "answer": "At Washington Dulles (IAD), passengers with disabilities can arrange wheelchair assistance through their airline at any concourse or terminal, and the airport offers accessible shuttle buses, rental car shuttles, and the Hidden Disabilities Sunflower Program with lanyards available from information desks and the USO Lounge daily from 8:00 AM to 8:00 PM. At London Heathrow (LHR), assistance should be requested through your airline, travel agent, or tour operator at least 48 hours before flying, and the airport provides free sunflower lanyards, accessible toilets, induction loops, help points, and dedicated assistance areas in each terminal. Neither airport mentions dedicated children's play areas in the accessibility materials, though Heathrow does note quiet areas and Changing Places facilities in departure lounges.",
        "toolsUsed": [
          "article_lookup"
        ],
        "references": [
          {
            "url": "https://www.flydulles.com/iad/disability-services",
            "title": "flydulles.com - Disability Services",
            "favicon": "https://www.flydulles.com/themes/custom/mwaa_barrio/favicon.ico"
          },
          {
            "url": "https://www.flydulles.com/",
            "title": "Official Website of Washington Dulles International Airport - IAD",
            "favicon": "https://www.flydulles.com/themes/custom/mwaa_barrio/favicon.ico"
          },
          {
            "url": "https://www.mwaa.com/",
            "title": "Official Website of Metropolitan Washington Airports Authority - MWAA",
            "favicon": "https://www.mwaa.com/themes/custom/mwaa_barrio/favicon.ico",
            "time_published": "2026-08-26T00:00:00Z"
          },
          {
            "url": "https://en.wikipedia.org/wiki/Dulles_International_Airport",
            "title": "Dulles International Airport",
            "favicon": "https://en.wikipedia.org/static/apple-touch/wikipedia.png",
            "time_published": "2026-09-18T13:47:09Z"
          },
          {
            "url": "https://www.mwaa.com/policefireems/fire-ems/fire-ems-washington-dulles-international-airport",
            "title": "mwaa.com - Fire & EMS at Washington Dulles International Airport",
            "favicon": "https://www.mwaa.com/themes/custom/mwaa_barrio/favicon.ico"
          },
          {
            "url": "https://www.heathrow.com/at-the-airport/assistance-and-accessibility",
            "title": "Assistance and accessibility | Heathrow",
            "favicon": "https://www.heathrow.com/etc.clientlibs/heathrow/clientlibs/vanilla-components/base/resources/favicon-57x57.png"
          },
          {
            "url": "https://www.heathrow.com/at-the-airport/assistance-and-accessibility/help-in-the-terminal",
            "title": "Help in the terminal | Heathrow",
            "favicon": "https://www.heathrow.com/etc.clientlibs/heathrow/clientlibs/vanilla-components/base/resources/favicon-57x57.png"
          },
          {
            "url": "https://www.heathrow.com/at-the-airport/assistance-and-accessibility/request-assistance-before-leaving-home",
            "title": "Request assistance before leaving home | Heathrow",
            "favicon": "https://www.heathrow.com/etc.clientlibs/heathrow/clientlibs/vanilla-components/base/resources/favicon-57x57.png"
          },
          {
            "url": "https://www.heathrow.com/at-the-airport/assistance-and-accessibility/assistance-departure-guide",
            "title": "Assistance departure guide | Heathrow",
            "favicon": "https://www.heathrow.com/etc.clientlibs/heathrow/clientlibs/vanilla-components/base/resources/favicon-57x57.png"
          }
        ]
      },
      "q17": {
        "question": "What aircraft are typically used on flights from Washington to London?",
        "answer": "British Airways primarily flies Boeing 777 family aircraft on flights from Washington to London. United Airlines operates a mix of Boeing 777 family and Boeing 767-400 aircraft. Virgin Atlantic serves the route as well, though no specific aircraft type is listed for its flights.",
        "methodology": "Aircraft types come from our flight-schedule database, which combines published airline timetables, U.S. government schedule data from the Bureau of Transportation Statistics (BTS), and observed flight operations from the EUROCONTROL/OpenSky Open Performance Data Initiative (OPDI). For U.S. routes the type is grounded in the tail number that actually operated the flight; elsewhere it comes from the airline's filed equipment code. Where the source does not commit to a specific variant we name the aircraft family (for example Airbus A320 family) rather than guess, and where no reliable type is on file the aircraft is omitted rather than estimated. Types describe typical scheduled equipment and can vary with seasonal or day-of-week assignments and last-minute swaps.",
        "toolsUsed": [
          "flight_schedule"
        ]
      },
      "q18": {
        "question": "Which airline alliances serve flights from Washington to London?",
        "answer": "Nonstop Washington–Dulles to London–Heathrow flights are operated by United (Star Alliance), British Airways (oneworld), and Virgin Atlantic, which is not a member of any global alliance. Other alliances may serve the route via connections, but these three carriers provide the direct service.",
        "methodology": "Airlines and weekly frequencies are compiled from our flight-schedule database, which combines published airline timetables, U.S. government schedule data from the Bureau of Transportation Statistics (BTS), and observed flight operations from the EUROCONTROL/OpenSky Open Performance Data Initiative (OPDI). We count each operating carrier's scheduled weekly departures and the days it flies; where there is no nonstop service, connecting carriers are identified by linking scheduled nonstop segments through common hub airports. Where a median fare is shown for a carrier, it reflects the real fares Priceline users found on this route in the last 72 hours.",
        "toolsUsed": [
          "route_airlines",
          "article_lookup"
        ]
      },
      "q20": {
        "question": "What are the best airport lounge options when departing from Washington?",
        "answer": "Washington Dulles offers several notable lounges, including the Etihad Airways Lounge on Concourse A, the Air France-KLM Lounge also on Concourse A, the Virgin Atlantic Clubhouse on Concourse A, and the Turkish Airlines Lounge Washington D.C. on Concourse B. The Capital One Lounge is located just beyond TSA PreCheck between the East and West security checkpoints on the Ticketing Level, with grab-and-go food and a full-service coffee bar available while enhancements are underway. Additionally, Lufthansa Business and Senator Lounges on Concourse B are temporarily closed.",
        "toolsUsed": [
          "article_lookup"
        ],
        "references": [
          {
            "url": "https://prioritypass.com/lounges/united-states-of-america/washington-dulles-international",
            "title": "Washington Dulles International Airport IAD Lounges - IAD Airport Guide and lounges. | Priority Pass",
            "favicon": "https://prioritypass.com/icon.png?icon.1k7202wk2zqql.png?dpl=1f82db4e-b1f8-481b-b911-c24ef915cc46",
            "time_published": "2026-08-18T11:40:12Z"
          },
          {
            "url": "https://americanexpress.com/en-us/travel/lounges/the-platinum-card/IAD",
            "title": "American Express Lounges at Washington Dulles International Airport | Amex US",
            "time_published": "2026-01-01T00:00:00Z"
          },
          {
            "url": "https://flydulles.com/travel-information/services-amenities/airport-lounges/capital-one-lounge-iad",
            "title": "Capital One Lounge - IAD | flydulles.com",
            "favicon": "https://flydulles.com/themes/custom/mwaa_barrio/favicon.ico"
          },
          {
            "url": "https://my.prioritypass.com/en-GB/lounges/united-states-of-america/washington-dulles-international",
            "title": "Washington Dulles International Airport IAD Lounges - IAD Airport Guide and lounges. | Priority Pass",
            "time_published": "2024-11-05T00:00:00Z"
          },
          {
            "url": "https://united.com/en/ca/fly/travel/airport/iad-map.html",
            "title": "Dulles International Airport Map | United Airlines",
            "favicon": "https://united.com/icons/icon-72x72.png"
          }
        ]
      },
      "q21": {
        "question": "What is the baggage allowance on this route from Washington to London?",
        "answer": "Baggage allowance on Washington to London flights depends on the airline and fare type. Basic Economy often does not include a checked bag, while standard economy typically allows one checked bag and a carry-on. Premium cabins usually offer two checked bags and a carry-on."
      },
      "q22": {
        "question": "What cabin and seat options are typical from Washington to London?",
        "answer": "Flights from Washington Dulles to London Heathrow usually offer Economy, Premium Economy on British Airways and Virgin Atlantic, and flat‑bed Business class, with First class available on British Airways."
      },
      "q23": {
        "question": "Are same‑day changes or standby possible on this route?",
        "answer": "Same-day changes or standby depend on the airline and fare class, with flexible and premium cabins offering the most generous options."
      }
    }
  }
}