SPOKANE, Wash. — A United Airlines flight that left Spokane International on Friday morning on its way to Denver had to divert to Seattle after it struck a bird with its windshield.

A spokesperson for United said all passengers aboard the flight are safe.

“Shortly after takeoff, United Airlines flight 812 from Spokane, WA to Denver experienced a bird strike and safely diverted to Seattle. Customers will continue their journey to Denver this morning,” United said in a statement.

RELATED: Flight from Spokane to Denver diverted after bird strike

This raises questions about bird strikes and planes, such as why strikes are diverted to other airports, and just how many of these incidents happen each year. We set out to answer some of those questions here.

Why did the plane divert to Seattle if Denver is in the opposite direction?

Glenn Farley, KING 5 Seattle’s aviation specialist, says that Sea-Tac “is considered a significant diversionary airport and can accommodate all planes on its runways and ramps. Its gates aren’t really set up for an A-380 (the plane struck today), but they could deal with it should they get one.”

How many bird strikes happen in the United States each year?

The FAA says there were 194,000 reported wildlife strikes in the U.S. between 1990 and 2017. About 14,400 of these happened in 2017 at 700 airports in the country. In addition to domestic wildlife strikes, 4,000 more of these incidents were reported by U.S air carriers at foreign airports from 1990-2017.

According to FAA statistics, 97 percent of wildlife strikes are birds.

As for Spokane, Marketing and Communications Manager Britt DeTienne says the airport has averaged 37 bird strikes annually over the past three years, but only one or two has damaged aircraft. Last year saw 38 reported incidents of bird strikes.

Glenn Farley says that “getting to a crash level is extremely rare, but there have been close calls worldwide with geese crashing through windshields and other major stuff.” 

Alexa Block, a KREM 2 reporter on the flight, says the captain told passengers the plane hit a flock of geese. 

The first bird strike in history was reported by Orville Wright over a corn field in Ohio in 1905.

How dangerous are bird strikes in air travel?

From 1988 to 2017, the FAA says there have been 287 deaths due to wildlife strikes globally. An additional 311 human injuries aboard U.S civilian flights from 1990 to 2017 have come due to wildlife strikes.

Eastern Air Lines Flight 375 crashed into Boston Harbor after striking a flock of European starlings upon take-off on Oct. 4, 1960, leading to 62 fatalities and the largest loss of life due a bird strike in history.

As for danger to aircraft, engines are the most commonly damaged part of an aircraft due to bird strikes.

Do aircraft like the one struck today have windshield wipers?

United Airlines flight 812, the one that struck a bird during takeoff today, is an Airbus A320. These planes do have windshield wipers, as most passenger jets do.