The title of largest aircraft ever built belonged to the Antonov An-225 until it was destroyed at Hostomel Airport in February 2022. Its successor as the biggest military lifter in service is the An-124 Ruslan — and a surprising number of these giants are currently grounded, caught out by sanctions and closed airspace.

Of roughly 55 An-124s built, just over 30 remain active. Some fly for air forces, others haul outsized freight — satellites, locomotives, helicopters — as commercial charters. Antonov Airlines operates seven and files flight plans like any cargo carrier, so you can follow them on public trackers. Volga-Dnepr's fleet tells a stranger story: nine aircraft listed, only three active. One has sat parked at Toronto Pearson since February 2022, when it delivered COVID-19 test kits and got stranded the moment Canada closed its airspace to Russian aircraft; a judge rejected the recovery bid, leaving it stuck for over four years. Three more sit idle in Germany, with others stored in Dubai and Ulyanovsk.

The United States fields the next two giants. The C-5M Super Galaxy is the largest plane in the US Air Force, 52 upgraded airframes capable of carrying over 127 tonnes, based at Dover in Delaware, Travis in California, Lackland in Texas and Westover in Massachusetts — Dover being your best bet for a look. The smaller but far more numerous C-17 Globemaster III (around 272 flying worldwide) is the one you're most likely to actually see, since it flies constant routine logistics and humanitarian missions under REACH callsigns with its transponder happily on. The RAF, India, Australia, Canada, Qatar, the UAE and Kuwait all operate it, plus a multinational unit at Pápa Air Base in Hungary.

China's Xi'an Y-20 is the fastest-growing fleet, with roughly 95-100 airframes built and the domestically built WS-20 engine now entering service. Its payload of 66 tonnes slots between the C-17 and C-5M, and it has flown humanitarian missions as far as Djibouti. But don't bother checking a tracker: Chinese military aircraft don't broadcast on civil networks, so everything known comes from satellite imagery and state media.

For European readers, the easiest giant to catch is the Airbus A400M Atlas. Germany's Luftwaffe operates the biggest fleet — 53 aircraft, all from a single base at Wunstorf — with France, the UK, Spain, Turkey and several others also flying it. Frequent training sorties over populated areas make it a regular sight, and its Seville assembly line still has 39 aircraft to deliver.

Why care if you're not in the military? Because these are the largest planes you'll ever see up close, and several are genuinely spottable. Watch the trackers around Dover or Charleston for C-5Ms and C-17s, park near Wunstorf for A400Ms, and follow Antonov Airlines' commercial An-124s as they criss-cross the globe. Just remember the golden rule of military spotting: the moment a mission turns sensitive, the transponder goes dark and the aircraft vanishes from view.