Bulletproof is relative. Kevlar may stop small arms fire but isn't worth a damn against a 155 Howitzer. As far as experiment aircraft engines are concerned and automotive conversions in particular the Corvair is probably as close to bulletproof as you're going to get with the minor exception of the Mazda rotary but that one has many more points of failure associated with it. i.e. reduction drives and cooing systems would top the list here. Doug Rupert
I remember a statement some time ago from someone that the Corvair engine was bullet proof. All engines can be broke. Defining these conditions and avoiding them is the goal. Ronald R. Eason Sr. -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.1.371 / Virus Database: 267.14.20/234 - Release Date: 1/18/2006