From Check-In to Luggage Collection: What Happens to Your Luggage When You Fly


    In 2022 alone, over 130 million people travelled through London’s 6 airports which demonstrates the complexity of modern airports, and passenger rates are only increasing after the pandemic. We take it for granted that we drop off our luggage at the check-in desk and pick it up when we land, but there is a whole system of operations that takes place while we wait to fly from London.

    From tagging at the bag drop and the intense security checks to the deadlines of loading and unloading and the infamous luggage carousel, there are many moving parts when it comes to flight baggage.

    Checking In and the Routine Bag Drop

    Checking bags at the airport is a straightforward yet crucial part of your travel process. When you arrive at the airport, you either head to your airline’s check-in counter or dedicated bag drop area if you’ve already checked in online. An agent weighs your bags to ensure they meet the airline’s size and weight restrictions. The weight of each person’s luggage is crucial because restrictions allow planes to run as efficiently as possible, and they reduce costs for the airline and ensure parity between passengers.

    Each bag receives a printed tag with your London-based departure destination, flight details, and a barcode for tracking. This tag also includes your final destination, vital for the bag’s journey through the airport’s behind-the-scenes conveyor systems and for sorting it onto the correct flight.

    The first stage in the complex maze of luggage handling is the initial sorting, most of which takes place on a conveyor belt. The tags applied at the luggage drop use a barcode that can be scanned at any point to ensure luggage is sorted correctly. Bags are then grouped depending on their destination and specific flight route, something which is often determined and executed via international flight planning services.

    Security Checks and Luggage Screening

    All airports in and around London have stringent and modernised security systems in place to ensure the safety of all passengers:

    • X-Ray: This technology can penetrate various materials, allowing operators to see the shapes and densities of items packed inside the bags. Different materials absorb X-rays differently, so organic materials, metals, and plastics all show up in distinct colours or shades, helping screeners identify the contents.
    • Explosive Detection Systems (EDS): These sophisticated X-ray machines are capable of detecting a wide range of explosive materials. EDS machines use advanced algorithms to analyse the images generated by the X-ray scan, comparing them to the characteristics of known explosives.
    • 3D Image Technology: Newer to the scene, this technology enables security personnel to rotate the image and inspect the bag from every angle, reducing the need for manual bag checks.
    • Trace Detection: In addition to imaging, trace detection devices are used to sample swabs taken from the exterior of luggage or from a passenger’s hands. These devices analyse the swabs for traces of explosives or narcotics, offering another layer of security screening.
    • Sniffer Dogs: Some airports also use specially trained sniffer dogs as part of the luggage security screening process. These dogs are trained to detect the scent of explosives, drugs, and other prohibited items. They may screen luggage as it moves through the airport or perform random checks in the screening areas.
    • Manual checks: If the screening technology flags a piece of luggage for any reason, or if something appears suspicious in the X-ray image, the bag may be subjected to manual inspection.

    Aircraft Loading and Unit Loading Devices (ULD)

    Once luggage has successfully passed through security checks, it is then loaded onto carts and trucks by the luggage handling crew before being driven to the correct gate. From there, it is loaded onto the aircraft before passengers get on board.

    For larger aircraft, luggage is placed into large containers called Unit Loading Devices (ULD) before these are inserted into the plane. This allows for greater efficiency in terms of space usage and overall timing. Smaller aircraft tend to be loaded by a dedicated ground crew who might use conveyor belts to reduce the amount of staff required.

    Regardless of how it is loaded, luggage needs to be secured into place to avoid it shifting during the flight which could affect the aircraft’s stability and balance. Final checks then take place and the loadmaster signs off, confirming that the cargo matches the final destination.

    Destination Unloading

    After landing at its final destination, the aircraft loading process is reversed and this must be done to tight deadlines to avoid people waiting for the luggage, and to avoid a backlog of flights needing their luggage to be processed and claimed. Elevated platforms are often used to remove ULDs and for smaller planes, luggage is often loaded onto carts with conveyor belts.

    Depending on the size of the airport, the luggage is then transported to the terminal area in different ways, either via conveyor belts through a series of tunnels, or manually via carts, trolleys, and trucks. Some of the larger airports around London use large motorised vehicles to transport luggage to the correct place. Just before being released at the baggage claim area, luggage is then sorted into groups to ensure they are unloaded at the correct belt.

    Baggage Claim and the Carousel

    Given that each flight has a separate luggage carousel, baggage must be sorted before being released into the claiming area which can be a complicated process, especially for Europe’s busiest airport. At this point, passengers are responsible for retrieving their luggage. However, some items will be too large or fragile to be released onto the baggage carousel and will be handled separately. Good examples include skis and musical instruments, which are often handled separately during each stage of the process in the first place.

    While pets are allowed on planes, each airline has its own set of policies to ensure the safety of animals and passengers alike. Small pets may be brought on board as carry-on luggage, larger pets may be placed in the pressurised cabin, sometimes in crates, and some are sent separately in advance.

    Now that you know the ins and outs of baggage handling, it might be fun to think about where your luggage is at each stage of your journey. From X-ray scanning and conveyor belts to Tetris-style packing and carousels, your luggage is on a trip of its own!