mec

First of all I want to say “thank you” to Dustflyer. He helped me and gave all the information where to order, how to setup and tune the engine and plane. Again: thank you Mr. Dustflyer. I enjoy flying the DD. Whats the nitro for the engine, is the adrenalin for me.

Today i did some test runs (weather conditions 20° Celsius) with my Jett FIRE 50 engine with high rise header and tuned pipe (mounted on a Diamond Dust).
1. test run: with header shortened half an inch, APC 8.8x9.25 pylon prop, 15% nitro, OS Glow Plug #5: 17.700rpm.
2. test run: with 3 inch longer header: 14.500rpm.
3. test run: with 2 inch longer header: 15.500rpm.
4. test run: again same length as test run #1, but 50% nitro, 15%aerosaveoil: 18.700rpm (engine very hot however, glow plug gone).
5. test run: again 50% nitro, glow plug OS #8: 18.400rpm (engine very hot, glow plug gone again).
6. test run: again 50% nitro, APC 8x10 sport, GP Rossi #7: 18.500rpm.
7. test run: 30% nitro, 15% aerosaveoil, again APC 8x10 sport, GP Rossi #7: 18.100 rpm.
8. test run: same as above but APC 8.8x9.25 pylon prop: 18.300rpm.
9. test run: same as above but 15% nitro: 17.900rpm.
10. test run: same as above but APC 8x10 sport: 17.800rpm.
11. test run: same as above but 0% nitro: 17.600rpm.

my conclusions: high nitro fuel on this engine brings slightly more rpm, but the disadvantages predominate (all my planes consume 15%nitro, so I need to carry an extra bottle with me, shortened life of engine, gone glow plugs).
My setup for flights is test run 10: 15% nitro, APC 8x10 sport turning 17.800rpm.
For high speed flights an APC 8x11 or 8x12 would be worth a try (but where to buy?).

For the next days I hope to manage to put my GPS on the plane to do some speed measurements (last flight of the hot spot with PJ 130 engine showed a max of 380km/h on the display, however with an opened gear door, followed by an failure in the gear and a belly landing, but new thinner wings).

mec