pyrotechnic vs pyrotechnical

pyrotechnic is a noun but pyrotechnical is not a noun.

Word	Noun	Adjective	Verb	Adverb
pyrotechnic	Yes	Yes	No	No
pyrotechnical	No	Yes	No	No

As adjectives, pyrotechnic and pyrotechnical are synonyms defined as:

pyrotechnic and pyrotechnical: of or relating to the craft of making fireworks

pyrotechnic (noun)	pyrotechnical (noun)
(usually plural) a device with an explosive that burns at a low rate and with colored flames; can be used to illuminate areas or send signals etc.

pyrotechnic (adjective)	pyrotechnical (adjective)
of or relating to the craft of making fireworks	of or relating to the craft of making fireworks
suggestive of fireworks