Hello,
After a long break from posting on HBA, taking glider lessons among other things, I'm back with a project:
I have purchased a Ka8 with the purpose of making it a jet-powered self-launching sailplane. I want to use a single 66lbf turbine, keeping the cost somewhat down and still giving enough performance.
The rate of climb would be 355 fpm, enough for where I plan to fly and fuel capacity would be approximately 5 US gal, giving me a 20 to 30 minutes endurance.
The only thing I'm struggling with is the TakeOff Parameter (TOP). Using TOP calculations from Aircraft design: A conceptual Approach, I obtained a TOP of 44, giving a ground roll of less than 1000 ft. I have some doubts about my calculations, the result seems too optimistic, or maybe it isn't given the fact that W/S is pretty low.
I have attached my calculations as a .pdf file, it would be very appreciated if someone could take a look at it and tell me if something is wrong. I can post a scan of the formula and diagram from the book if that's allowed.
Any comments are welcome
Thanks
P.S. I left the EPB-1 thread unanswered but I saw that someone posted a link to the plans, thank you for that.
After a long break from posting on HBA, taking glider lessons among other things, I'm back with a project:
I have purchased a Ka8 with the purpose of making it a jet-powered self-launching sailplane. I want to use a single 66lbf turbine, keeping the cost somewhat down and still giving enough performance.
The rate of climb would be 355 fpm, enough for where I plan to fly and fuel capacity would be approximately 5 US gal, giving me a 20 to 30 minutes endurance.
The only thing I'm struggling with is the TakeOff Parameter (TOP). Using TOP calculations from Aircraft design: A conceptual Approach, I obtained a TOP of 44, giving a ground roll of less than 1000 ft. I have some doubts about my calculations, the result seems too optimistic, or maybe it isn't given the fact that W/S is pretty low.
I have attached my calculations as a .pdf file, it would be very appreciated if someone could take a look at it and tell me if something is wrong. I can post a scan of the formula and diagram from the book if that's allowed.
Any comments are welcome
Thanks
P.S. I left the EPB-1 thread unanswered but I saw that someone posted a link to the plans, thank you for that.
