Js3 jet catastrophic failure.

On Tuesday, October 27, 2020 at 6:28:26 PM UTC-7, wrote:
On Tuesday, October 27, 2020 at 5:47:32 PM UTC-7, 2G wrote:
On Tuesday, October 27, 2020 at 9:41:31 AM UTC-7, wrote:
I really like what Chris has done and have reached out to him. What's on my mind is two 40kg class engines. You would have 175lbs of thrust, and in the event of one failing, you still have an adequate sustainer. I'm estimating the system would be around $25,000 (15k for the engines and 10k for the install). Where I am guessing entirely is the cost of the install, and if there would be enough room for two of this size engine. Two P300s are 10.5" wide next to each other, while two 40kg motors would be 11.5". So it seems they would fit in a lot of cases.

Interestingly, the P300 has a bit of a track record of catastrophic failure. I'm sure there is an explanation out there as to why, but I followed many incident threads and I never found a definitive answer. There was speculation that the rotor sizing resulted in a resonant frequency that was causing stress on the bearings.
I think you are way off on the install, by a factor of 3 to 5, assuming the engines are retractable. Obviously, multiple installs on the same model glider would be less.

Tom

Oh wow.. so people are charging $30,000 - $50,000 to install the door and retraction system? Like the one Chris did or the 1-26 at the convention? Paying more for the retraction system than the glider itself seems off to me for some reason.

You are talking about a structural change to the glider, plus a significant mechanical extend/retract system. This would normally require professional engineering design in addition to fabrication and testing. And it may require FAA approval depending upon the glider's registration. I think you would be lucky if this were all that it cost.

Tom