DENSO Iridium Power Spark Plug IX27B

Hi Kari

None really.  As long as you know that Denso is not approved for aircraft use and assume any risk then it is up to you to determine the suitability of the plugs.  ND decided not to support the applications where their plugs are used in flight, you can see this by the warning on their web pages.  (copy attached) 

Cheers

So no using the spark plugs in ludicrously swept wing propeller planes or electric quadcopters? ?

Whoever designed that warning page didn't do his research!

If you do use those spark plugs the biggest thing is knowing when they need to be changed. They'll probably last longer than the Rotax or older NGK because of iridium but you won't know  how much longer, so you will replace them too often and waste money or you'll keep them in to save money but possibly keep them in too long.

IF you're experienced enough to determine for yourself how well they perform it'll be fine.