DOC KB-TRV-011REV 2026-09-21CLASS: PUBLIC

Flying with Equipment Cases: Airline Rules, ATA 300 and Transit Prep

Direct answer

Most airlines accept checked cases up to 158 cm (62 in) in total linear dimensions and 23 kg standard weight, beyond which oversize/overweight fees apply. Professional flight cases are built to ATA 300 Category 1 for repeated air transport. The two most common travel problems are lithium-battery rules — which apply to your contents, not the case — and cabin-altitude pressure differences that bulge or lock a fully sealed case unless it has a pressure relief valve.

§01Checklist before the airport

§02Passenger flight vs air freight

ModeGoverning rulesCertification to look for
Checked baggageairline conditions of carriage; IATA lithium rulescase robustness is your own risk
Air freight (cargo)IATA T1/T2 packaging rules, DG where applicableATA 300 Cat. 1, ISTA procedures
Touring/demo programsrepeated trips, handlers, trucking legsATA 300 Cat. 1 with flight-grade hardware

§03Why the case feels different after a flight

Cargo holds are pressurized to roughly 2,400 m equivalent altitude, and temperatures swing far outside cabin range. A sealed case experiences both a vacuum on ascent and overpressure on descent. Membrane pressure valves equalize automatically; twist valves should be opened shortly before and after the flight. Neither is a safety issue for the aircraft — it is purely about protecting your latches and gaskets.

REF KB-TRV-011 · Published 2026-09-21 · Reviewed by the KeXin Materials engineering team · Sources: IEC 60529; ISO 6346; ATA 300; MIL-STD-810; Incoterms® 2020