AeroVironment Inc. said Tuesday it swung to a loss in its fiscal first quarter as some customer deferred deliveries of its Raven drone aircraft.

After the markets closed, the Monrovia company reported a net loss of $3.6 million (-17 cents per share) for the quarter ended Aug. 1, compared with net income of $4.8 million (22 cents) a year ago. Revenue fell 29 percent to $37.9 million.

Analysts surveyed by Thomson Reuters on average expected the company to earn 13 cents a share, before one-time items, on revenue of $52 million.

The deferred deliveries were blamed by Chief Executive Tim Conver on the decision by some customers to wait for new systems and upgrades to the Raven that will be available in the second half of the year

“We expect the availability of digital Raven systems to drive increased revenue in the second half of the year as our Raven customers seek to catch up on their deferred deliveries,” he said in a statement.

AeroVironment shares, which earlier closed up 88 cents, or 3 percent, to $30.42 on the Nasdaq, fell 8 percent in after-market trading.