If you say that an action or plan is uneconomic, you think it will cost a lot of money and not be successful or not be worth the expense. It would be uneconomic to try and repair it cost-effective
If you describe something such as an industry or business as uneconomic, you mean that it does not produce enough profit. the closure of uneconomic factories The company said the service was uneconomic. = unprofitable profitable
If you say that an action, a method, or a product is uneconomical, you mean that it does not make a profit. It would be uneconomical to send a brand new tape The methods employed are old-fashioned and uneconomical Even the successful flying boats proved, in the end, uneconomical. = unprofitable. using too much effort, money, or materials to make a profit
inefficient in use of time and effort and materials; "a clumsy and wasteful process"; "wasteful duplication of effort"; "uneconomical ebb and flow of power"