TANKS!

123456789
Across
  1. 4. This monster has a 380mm rocket propelled mortar.
  2. 6. According to Guinness, the world's smallest tank.
  3. 8. Full name of the Panzer IV.
Down
  1. 1. 73 Easting's winningest MBT.
  2. 2. O-ring failure, 1986.
  3. 3. First tank to use a gas turbine engine.
  4. 5. Including it's variant, over 50,000 were built in WW2 by the USSR.
  5. 7. "Object 148"
  6. 9. An upgrade to the Sherman, also a SciFi show.