One unique structural force that Mars habitats must contend with if pressurized to Earth's atmosphere, is the force of air on the inside walls.[1] This has been estimated at over 2,000 pounds per square foot for a pressurized habitat on the surface of Mars, which is radically increased compared to Earth structures.[6] A closer comparison can be made to crewed high-altitude aircraft, which must withstand forces of 1,100 to 1,400 pounds per square foot when at altitude.[6]