Final answer:
Airliners or any aircraft with pressurized cabins are not authorized to transport cryogenic tanks due to the need for an overboard vent system to vent excessive pressure.
Step-by-step explanation:
In the context of aircraft, there are certain safety requirements when transporting cryogenic tanks.
The aircraft that is not authorized to transport cryogenic tanks due to the need for an overboard vent system is an airliner or any aircraft with pressurized cabins. This is because cryogenic tanks contain materials such as liquid oxygen or nitrogen, which can become highly pressurized in flight.
If an overboard vent system is not present, the excessive pressure inside the cryogenic tank could cause it to rupture, leading to a hazardous situation. Therefore, aircraft authorized to transport cryogenic tanks must have the necessary venting systems to safely release the excessive pressure.