I’m talking about recreational SCUBA diving and General Aviation. Which activity results in more injuries? Deaths?
While I’m sure there’s an overall death rate for each activity, please keep in mind that “scuba diving” and “general aviation” are not just one activity but a collective.
In flying, for instance, ultralights and homebuilts have a higher injury/death rate than activities in factory-built Pipers and Cessnas. Certain forms of training will decrease your risk of injury or death. In certain instances, the airplane you fly will have an effect - statistically, it’s safer to have an engine failure and off-field landing in a single-engine airplane than in a twin engine, and if you do have an - >ahem< - unscheduled landing in general the smaller and slower your airplane the more likely you are to walk away from it.
Also, general aviation also includes such things as arial fire-fighting, and medical evacution, all three of which can be considerably more hazardous than flying out to a pancake breakfast on a fair Sunday morning.
I don’t scuba, but even from my outsider’s perspective I can see some similarities. Cave diving, for instance, is much more risky than tootling along an underwater tourist park at 25 under with a guide. Depth makes a big difference. Cold vs. warm water. Lake diving and ocean diving have different hazards.
In either case, safety (or lack thereof) depends a great deal upon the individual. A particular person may be more safe than average, or less. As a result, both activities are areas where you, personally, can do a great deal to lessen your own risk of pariticpation by choosing your actions wisely and following safety procedures.
So… are you asking about danger rates overall or in particular sub-categories of these activities?
Overall. As you say, there are different levels of risk inherent to the various types of diving and flying, and I’m going to assume that they cancel each other out. Perhaps not a good assumption, but I’m looking for a general picture.
BTW: I hold a Commercial Pilot’s ticket, and I think you are correct that the individual in question holds the key to safety. I consider flying safe FOR ME because I am quite careful.
I have no diving experience. But I’m guessing there are more inherent risks to diving due to the nature of the activity. But I am prepared to be proven wrong by someone who knows better.