I hope that is the right forum to post to. What follows may seem like it has more to do with economics than engineering but that is not the case: the economics is straightforward but the engineering may not be. In long-range passenger flights there are 3 classes: 1st, business, and economy. Most people that I know do not really care about the champaigne when they buy a business ticket; they buy it for the legroom. Some people are budget constrained and may not be able to afford a business ticket, say, for $5000. But they detest traveling in the knee-scraper (economy) class for, say, $1000. If there was a type of seat that gave them half the extra legroom of a business seat for, say, $3000, they'd buy it in a heartbeat. So the question is, why do the airlines not supply those seats? In the limit, why isn't legroom purchased on a continuous basis (e.g., $200/inch)? Economically, this will not hurt airline profits and may increase them, even under full capacity. For the suspecting, here is a counterexample. As a thought experiment, imagine that a passenger buys an economy ticket for himself, and then also buys the seat directly in front of him. He pays $2000 for the two seats ($1000 each). He then removes the front seat and tosses it out of the exit, gaining extra legroom instantly. The airline has not lost any money: the passenger has paid the full price for both seats. On top, the airline may have saved some costs because there is one fewer passenger traveling (although as many seats were sold), but let's put these cost savings aside. In this case, the passenger has ended up with twice the legroom plus the depth of the front seat. This is more than what he may have been ready to accept for the price he has paid: twice the legroom. In this hypothetical scenario the airline cannot lose money. But the airline can strictly increase profits if it were to sell twice the legroom, instead of "twice the legroom plus a seat depth," for $2000. My question is, why don't we see this happening? What are the techinical / engineering costs that must be keeping none-too-shy airlines from grabbing this moneymaker of an idea?