Imagine David. David is an airline captain lincenced to fly B737, B747-400, B-747-800 and any B777. David flies Lufthansa's B747 from Frankfurt to Chicago. When he arrives to Chicago, he checks in to a hotel near the airport that he booked and decides to wander around the city for a while, as he doesn't yet want to sleep. Maybe visit his old friend if he's not busy. Or maybe have a dinner somewhere. Why doesn't he want to sleep after a long flight? Well, most probably, he took a nap in the cabin while his replacement pilot took place for a little while. And now his bilogical clock is in a state of evening awarness (for more info on that, please refer to William C. Dement's "The Promise of Sleep"), which means no matter how hard he tries, he won't be able to fall asleep for at least 2 more hours. David then returns to a hotel after 4 hours outside completely exhausted, takes a shower and prepares to go to sleep. Just before he puts his head on a pillow, he takes his phone and checks in on a website for freelance pilots, stating that he'll be available in 11 hours for any flight back to Europe on any plane he's licenced to fly. He estimates that he needs about 9-9,5 hours of good sleep, then 30 minutes to pack, 30 minutes for a breakfast and then 30 minutes to get to the airport. Thus, he states he'll be ready to confirm any offer in 10 hours.
When David wakes up, he sees 3 offers in his Inbox. Unfortunately, an offer from United for a flight back to Frankfurt, where he lives, has already been taken by another pilot just 10 minutes ago. First officer position is still available for the same flight, but that's less pay, so he doesn't want it. There are two other flights, one is British Airways to London on a B747-400 and another one to Paris by Air France on a B777-300ER. The latter pays more, although the flight time is slightly longer. Since David just woke up and the flight departs very soon, he decides to fly to Paris, so he clicks "Accept" on it and then goes to shower.
When he comes back from the shower, he remembers to check his Bitcoin wallet and finds out that the pay for yesterday's flight has already arrived. He dresses up, packs his bag and heads down to have a breakfast. He arrives at the airport not long after that and there he meets his co-pilots who also signed up for this flight, both americans: John and Edward. He talks to them and finds out that Edward woke up 6 hours ago while John woke up just 3 hours ago. He then assigns John to be his first officer at take off, while Edward will be resting for the first 5 hours to replace David for a while later, if it is necessary.
After they arrive to Paris David checks into a hotel near the airport and starts looking for flights to Frankfurt that need pilots. He finds one that is scheduled to depart in 5 hours, but the freelance pilot website doesn't allow him to sign up for it, since he didn't have enough rest yet. He then finds another Lufthansa's flight scheduled to depart in 15 hours. While he would only need his regular 7,5 hour sleep now, and, thus he will then be awake for 7,5 hours more before that flight, he knows the flight is going to take just a couple of hours, so he'll be able to perform it, so he signs up for it. Just before going to sleep he checks his Bitcoin wallet just to see the pay for his previous flight arrived: looks like Air France is faster with payments!
Unlike many free market opponents would suggest, it's not just for the money. Surely, you can expect freelance pilots to be paid more, since Airlines wouldn't need to take care of all the other things for them. However, many people also want more freedom in how they live their lives. Maybe they want to control their schedule. Maybe they want to fly to various places their airline doesn't fly. Maybe they don't want to wake up when they're told to. In fact, this last one is not just a matter of preference, but also a safety issue. So much so that NTSB cites sleep problems contributing to many accidents. And the issue is only partially resolved by allowing naps in the cockpit. To achieve maximum safety, pilots should take flights that start as close to them naturally waking up as possible. Unfortunately, it is difficult as hell to achieve unless you allow freedom of choice for which flights should be taken.
Of course, there are many issues to be solved with such a system, but potential gains are great. One issue is regulations preventing airlines from hiring freelancers, which are in part true safety concerns and in part a result of unions influence. Remove these regulations and replace them with sane signing-up-for-flights procedures and you'll do just fine. Another issue is language barrier, which, in fact, is a problem anyway, since ATCs and pilots are communicating in English and sometimes misunderstand each other. All pilots should learn to speak proper english and having an international team would only fascilitate this process. Yet another issue is various safety standards and procedures in various airlines, which, again, should become a non-issue when airlines lean towards more standard procedures to attract more freelancers.
It may also be suggested that flights would be delayed because no pilot signs up. While that's possible, it is highly unlikely in a developed free market system where supply and demand work unconstrained. You can expect, for example, airlines to raise prices to attract pilots for specific destinations. Even if it happens so that no one signs up, then airlines might have some pilots "on call" who can take over a flight no matter what. In any case, I'd rather have my flight delayed than fly with a pilot who didn't get enough sleep last night because his biological clock is fucked up.
Some may also suggest there's a danger to allow free market take over such a delicate process as pilot assignment, since young inexperienced pilots would take flights for lower pay, thus endangering the passengers and pushing experienced pilots out of the market. This also sounds very unlikely, since airlines may prevent this easily with the demands they set for freelance pilots for each specific flight. Even more interesting is that passengers would now be able to see pilot experience demands for each flight and decide whether they want to fly this airline based not only on aircraft type and price, but also on the experience of the crew. In general, any regulation that makes sense now, could esaily be incorporated into such a freelance system, while other regulations and rules that don't make sense, can be left out.
So, to sum it all up, a system of freelance pilots would allow:
The only two reasons this system is not widespread now are regulations and unions. I'm more than convinced had regulations allowed for such a system and had not the unions had so much power, you'd see this happening already.