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Old 09-22-2017, 08:17 PM
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olnico
 
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Originally Posted by CRye
Ola, Gaspar,I have a JM200XBL I purchased as the third owner but never started. It was originally sold by Dreamworks.I have installed it in a used Aurora I spent the last year correcting substandard work on.My pipe is 83mm inner diameter and 34 inches, about 850mm long.I understand from Todd, Dreamworks the ID is marginal and I should keep a watch for heat stress ie bluing of the stainless.I currently have a forward smoke pipe at the entrance of the pipe but I plan to change to end of pipe before I run smoke. Partially out of concern for the pipe.

I want to make some flights before I change the pipe.
What is the optimum inner diameter for this length pipe on a 200? I prefer takeoff thrust over max speed. Do you consider 83 mm x 850 to be a hazard if watched? I don’t fly full throttle much.

Thank you

Charles
Wow. You are going to implode that pipe at no notice in flight.
It is way too narrow for the length.

Gaspar's 200 has a pretty high efflux velocity. On a 850 mm pipe, I would recommend 110 mm ID to keep the vacuum levels in the pipe reasonable.

Last edited by olnico; 09-22-2017 at 08:19 PM.