One of a pair, which smacked into a window and flew around inside until ushered out. It sat on the tarmac recovering for a few minutes and then both of them flew around squawking before zipping into an open hangar to incite more ruckus.
(it's not attacking/being hit by the sign in the photo; it had perched on the end and was being gently tipped onto the ground)
Stubby tails and white butts.
Jeffrey pine, South Lake Tahoe
Small-coned pine, South Lake Tahoe.
Leaves are around 5 cm, and cone is slightly shorter.
Needles are bundled in pairs.
This identifies a lodgepole pine, and the Sierra Nevada location gives the murrayana subspecies.
White fir, South Lake Tahoe
Young pine, Angora Ridge.
Mid-length needles, around 5 cm. (longer than a fir, shorter than Jeffrey).
It looks like some bundles of 5 leaves are in the photo.
The needles struck me as too short for a Sugar Pine, though my experience was with the ones in dry southern California.
If true, this seems to leave P. alibicaulis or P. monticola as the most likely species.
Red fir, Angora Ridge