I would love to hear more about the flight parameters (OAT, winds, location, time, estimated numbers, problems encountered, etc.)
Insects can be "seen" with some radar if the algorithms can be determined.
From: The Birds of Arkansas Discussion List [mailto:<ARBIRD-L...>] On Behalf Of Donald C. Steinkraus Sent: Thursday, October 25, 2018 11:30 AM To: <ARBIRD-L...> Subject: Re: monarchs altitude
I have often wondered the same thing. I have seen them flying south over Fayetteville at the limits of my vision. Your observations of a plane hitting them at 14,000 feet is amazing.
From: The Birds of Arkansas Discussion List <ARBIRD-L...> on behalf of Jacque Brown <bluebird2...> Sent: Wednesday, October 24, 2018 5:02 PM To: <ARBIRD-L...> Subject: monarchs altitude
Off subject a bit. While at the Ninestone field trip Sunday we were seeing quite a few Monarchs as well as birds. we got into a discussion of how high they fly, I commented that My sister and brother in law have a plane and were flying at 10,000 ft when they hit a flock of Monarch Butterflies. They had to land to clean off the plane. I e mailed them to check my memory, I was wrong about the altitude. It was 14,000 ft.
They live in Colorado but I don't remember where they were headed when they ran into them. Rex's family lived in New Hampshire. I think it may have been on the way home from there.