Hi,
we have a C182J, authorized by the country's aviation to do skydiving.
The plane has the air deflector, and the step.
We recently purchased a used skydive jump door for the C182J, which opens upwards.
We steal and use this door for our business, but we do not have the STC for this used door.
Is it obligatory to have an STC? If yes, is it obligatory? we want to buy the STC paper but we don't know who made this door modify.
thank you for your feedback.