[uccprince]

It does work as long as you're not in a pressurized cabin. I've used my X6HR to measure and log flights in both a glider and private aircraft. Makes for some very interesting profiles.

All commercial flights are pressurized, and since the Suunto uses barometric pressure to estimate altitude, it doesn't work on these. The average long haul flight has a cabin pressure equivalent to being about 6000 feet above sea level.

The compass does seem to work on all flights.

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