* Planemaker posts $94 mln loss vs year-ago profit
* 663 mln reais provision on American Airlines bankruptcy
SAO PAULO, March 20 (Reuters) - Brazil's Embraer, the world's third-largest aircraft maker, booked a net loss on Tuesday due to a provision for the bankruptcy of American Airlines, wiping out solid revenue growth in the fourth quarter.
Embraer posted a fourth-quarter net loss of 171.6 million reais ($94 million), compared with a profit of 208 million reais a year earlier, the company said in a securities filing.
The aircraft maker's results suffered as it set aside a provision of 662.6 million reais due to the Chapter 11 bankruptcy of key client American Airlines, which is renegotiating the leases on its Embraer fleet.
The aircraft maker was expected to post a $143 million profit in the quarter, excluding the impact of any provisions, according a Reuters survey of seven analysts who gave their estimates in dollars. Embraer reported its results on Tuesday in Brazilian reais.
Embraer's last such provision came when the company booked 179 million reais in losses last year related to the warranty protection it provided to bankrupt U.S. airline Mesa Air Group Inc.
The company said the provision booked in its fourth-quarter earnings covered any additional liabilities related to Mesa that could result from the bankruptcy of American Airlines' parent company.