You have to love those low passes, my buddy did the same thing over a year ago, look at post #8 in the following thread.
http://www.rcuniverse.com/forum/m_63...tm.htm#6300402
He was able to "Trim" both booms
His repair was quite simple, glue in a block of balsa to the bottom, reshape and cover, now you can't tell it ever happened.