Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of AeroVironment (AVAV -0.79%) have surged 14% higher today following the release of the high-tech drone manufacturer's fiscal 2014 fourth-quarter earnings results.

So what: AeroVironment's 2014 fiscal year ended with a bang on April 30, as quarterly revenue shot 36% higher year over year to $73.5 million, pulling earnings up to a whopping $0.36 per share. Both figures trounced Wall Street's consensus, which had called for $69.6 million in revenue and $0.23 in EPS. This was driven largely by the quarter's 42% year-over-year surge in unmanned aerial vehicle sales, to $60 million.

AeroVironment also boosted its revenue guidance for fiscal 2015 from the earlier $230 million-$250 million to a new range of $250 million-$270 million. This comes in well ahead of the current Wall Street top-line consensus of $254 million, but a gross profit margin estimate of 34.5%-37.5% produces $93.6 million in gross profit. That's a bit weaker than 2014's realized gross margin of 37% (gross profit was $93.6 million for fiscal 2014on revenue of $251.7 million) when using the midpoints from both guidance ranges.

Now what: If we assume that AeroVironment will wind up with a similar distance between its gross and net margins next year as it did for fiscal 2014, it will collect roughly $13.9 million in net income, which represents earnings growth of only 1.5% over 2014. Its revenue guidance for fiscal 2015 also offers a weak 3.3% growth rate from 2014's revenue. That's still a long way from the high-water marks of the 2012 fiscal year, which saw AeroVironment post $325 million in annual revenue and $30 million in net income, for EPS of $1.36.

AeroVironment's P/E ratio has been stuck near all-time highs in the triple digits this year. Weak projected growth plus record-high valuations generally don't produce good returns going forward. Potential investors should probably avoid this stock for the time being.