Air National Guard flies with Heritage Flight Museum's historic P-51 Mustang at Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/Invision for John Klatt Airshows, Inc./AP Images)

Air National Guard and the Heritage Flight Museum's P-51 Mustang takes to the skies at Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/AP Images for John Klatt Airshows, Inc.)

Air National Guard and the Heritage Flight Museum's P-51 Mustang takes to the skies at Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/AP Images for John Klatt Airshows, Inc.)

Air National Guard flies with Heritage Flight Museum's historic P-51 Mustang at Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/Invision for John Klatt Airshows, Inc./AP Images)

Air National Guard takes to the skies over Puget Sound during Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/AP Images for John Klatt Airshows, Inc.)

Air National Guard and the Heritage Flight Museum's P-51 Mustang takes to the skies at Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/Invision for John Klatt Airshows, Inc./AP Images)

Air National Guard takes to the skies at Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/AP Images for John Klatt Airshows, Inc.)

Air National Guard takes to the skies over Puget Sound during Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/Invision for John Klatt Airshows, Inc./AP Images)

Air National Guard flies with Heritage Flight Museum's historic P-51 Mustang at Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/Invision for John Klatt Airshows, Inc./AP Images)

Air National Guard takes to the skies over Puget Sound during Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/Invision for John Klatt Airshows, Inc./AP Images)

Air National Guard takes to the skies at Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/AP Images for John Klatt Airshows, Inc.)

The Heritage Flight Museum's P-51 Mustang takes to the skies at Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/AP Images for John Klatt Airshows, Inc.)

Air National Guard and the Heritage Flight Museum's P-51 Mustang takes to the skies at Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/Invision for John Klatt Airshows, Inc./AP Images)

Air National Guard and the Heritage Flight Museum's P-51 Mustang takes to the skies at Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/AP Images for John Klatt Airshows, Inc.)

Air National Guard and the Heritage Flight Museum's P-51 Mustang takes to the skies at Seafair 2015 on Thurs., July 30, 2015 in Seattle, Wash. (Photo by Matt Mills McKnight/AP Images for John Klatt Airshows, Inc.)