Engine exhaust damaging things that are seemingly out of the way

Steps to reproduce:
1. Take off
2. Fold the landing gear
3. Activate the "laser" by putting slider 1 all the way up and activating AG 9

Result: Various parts, including the wings and vertical stabilizers behind the engine, will quickly heat up and explode. For the purposes of this bug report the exhaust scale has been reset to 1, but the same effect happens at higher scales, which isn't ideal for a beam weapon.

Screenshot of the result (exhaust scale is increased here):