Grounding their concerns, Missouri senators passed a $240 million package of state tax enticements Thursday aimed at landing a Canadian company’s new airplane assembly plant at Kansas City International Airport.

The incentives for Bombardier Aerospace cleared the Senate by a 24-8 vote, but only after the state revised its offer by reducing the tax credits, delaying their start date and adding greater protections for taxpayers in case the project turns sour.

To reach Gov. Matt Blunt, the legislation now needs only a final vote in the House, which gave overwhelming approval to an earlier version. Even so, there is no guarantee that Montreal-based Bombardier will locate its new assembly plant in Missouri instead of its home country.

The original proposal would have granted Bombardier up to $40 million annually in tax credits for 22 years – theoretically reaching $880 million. The tax credits would have begun in 2010.

The revised plan would delay the tax credits until 2013 and cap them at eight years and a total of $240 million.