[xb95]

Only slightly less euphemistic than flying's CFIT - Controlled Flight Into Terrain. AKA "whoops, the ground".

[hudibras]

And going the other direction, euphemistically-wise, the U.S. military's official designation for things* that fall off aircraft is TFOA: Things Falling Off Aircraft.

*Anything from loose nuts or fasteners up to improperly-attached fuel tanks or bombs.

[SAI_Peregrinus]

Also known as lithobraking.