BA had its run to 400's but never made it back up. Furthermore, the price is breaking down lower towards August Low while other major name stocks are making all-time highs = It shows a strong selling pressure, no buyers showing up even during a bull market. The enthusiasm for the stock has died off. This selling is fueled by uncertainty and fear.
Intraday trades: Any move to the upside is a good swing for shorts. Unless unusual volumes of buyers can turn around the sail, I am using the above levels of support as a guideline for future trades.
The bigger picture: The breakdown of BA may be the lead indication of next year's correction, sales and growth slow down in the U.S. economy should not be overlooked.