There are four environments that occur as the altitude increases.

Rising air expands and cools due to the decrease in air pressure as altitude increases.

As altitude increases, tethers increase in length, the temperature of the air changes, and vulnerability to atmospheric lightning changes.

When the aircraft climbs above the critical altitude, engine power output decreases as altitude increases, just as it would in a naturally aspirated engine.

As the altitude increases, the pressure exerted by these gases decreases.