Flying Coffin ..what

I found this; http://www.asme.org/kb/news—articles/articles/aerospace—defense/the-flying-coffins-of-world-war-ii

Googled for flying coffin. It is a WW II towable glider.

Here Indian AF has 500th crash; http://rupeenews.com/2008/09/world-record-200th-indian-flying-coffin-mig-29-crashes/

More; http://www.dailymail.co.uk/indiahome/indianews/article-2138553/Flying-coffins-Half-MiGs-lost-deadly-crashes.html

Is Mig-21 like the F-20 Tigershark..too much to handle ?

It seems that F-104 STARFIGHTER was also a Flying Coffin; http://aircraft.wikia.com/wiki/F-104_Starfighter