Where did you learn to use a calculator? I didn't even check your sources and values, because the math, logic and subject area knowledge alone are terrible enough.
First, maths: you're off by one order of magnitude. 26,8 billion dollars for 16,4 million flights is 1'634 USD per flight. So it's 1,6k per plane, not 16k.
Second, logic: you've duly noted that only 55% of those 16,4 million flights are passenger flights, but calculate them as if they're all passenger flights with 104 pax average per flight, even compounding rounding errors as you go, omitting the 45% cargo-only flights and pretending that shippers for cargo don't need to pay for air traffic security.
Third, subject area knowledge: there are no true scheduled "passenger-only flights" in commercial aviation. What laypeople call "passenger flights" are actually only flights where some air cargo capacity is used by passengers and their luggage. Especially on transcontinental and long-haul flights, "passenger planes" carry an extraordinary amount of air freight and their profitability is hugely dependent on that as well. Making the airline passengers pay the entire flight security tax of that flight would mean the cargo shippers ride tax-free. That's not what we're after.
Cargo shippers, commercial operators, producers, assemblers, too, have their choice of using long-haul trucking, trains, air freight, boats, pigeon carriers or switching to localized production, bulk transport, to and from just-in-time logistics etc.. If company A wants to avoid setting up a warehouse near their production facilities to store all the bits and pieces they need on-site and with sufficient stock to allow for bulk transport, that's their prerogative. Only they can know if the capital assets locked in raw materials are too much compared to just-in-time logistics buying and transporting only the part that's actually needed right now. And air freight costs and air traffic costs play right into that. If company A wants to do just-in-time logistics and company B and C optimize their logistics, localize their production, keep reserves on site? Guess what, A pays the air traffic safety tax, B and C don't.
Same thing. And we can't count the number of boxes or metric tons of cargo vs. passenger counts and the number and weight of their luggage to even properly estimate the actual cost per passenger.
To re-use your simplification to get the absolute upper bound of that tax: if all those 16,4 million flights were passenger-only, air cargo didn't exist like you pretended, and all the flights had 104 passengers on average, then the cost would be 1,6k per flight or 15,71 USD per flight per passenger. Fifteen bucks per flight, at the very maximum, if air cargo didn't exist or was tax-free. And 104 passengers per plane is an absolutely ridiculously low number that applies only to the US domestic market. It doesn't even include the transcontinental flights coming and going to the US, because those are wide-body twin-aisle aircraft that have a LOT more than 104 seats. The top 10 current wide-body aircraft models for long-haul routes have over 200 (737) or over 800 seats (A380). Except these two extremes, most other types carry between 300 and 400 people. They're not flying 70% empty for that "104 passenger on average" number. If airlines actually allow to fly their planes half-empty, that's not a problem for the taxpayer to fix.
No taxation without representation. No taxation to correct or support voluntary and luxury decisions by others. You want it, you pay for it. End of story.
