Boeing Co. offered a 30% pay bump directly to striking workers, bypassing furious union leaders as it tries to overcome a debilitating strike that has shut down its aircraft manufacturing across the Pacific Northwest.

Boeing's (NYSE:BA) "best and final contract offer" will not be put to a vote by its largest union, as negotiators claim the proposal was made public without any discussion and does not go far enough to address workers' concerns.

Boeing's latest offer includes upfront pay raises of 12% plus three annual raises of 6% each. It would double the size of ratification bonuses to $6,000. It also would keep annual bonuses based on productivity. In the rejected contract, Boeing sought to replace those payouts with new contributions to retirement accounts.