Hypersonic electric propeller plane (Stock)

[Tyr Anasazi]

Hi all,

I've been away for a while - work, travel & life all conspired to keep me away from Kerbin. I have now returned, and decided to revisit my Spinner M2 craft.

I am trying to better understand how these rotors function as speed increases. Aside from craft modifications, I used the console to tweak the lift/drag ratio setting.

The result is Spinner (pictured below) reaching a hypersonic speed of Mach 5. 

While this is not strictly stock as the lift/drag ratio setting has been changed, it shows that there is room for improvement beyond the Mach 2.1 speed this craft achieved last year.

While typing this post, Spinner continued to accelerate and is currently flying at Mach 5.4 at 17,500m. It's still climbing. I will leave it flying and see what happens. (Update: it exploded before reaching Mach 5.5)

Some observations:

• Spinner achieves top speed with its rotors turning at approximately 470 RPM. Slower and it can't accelerate, faster and it explodes.
• The RPM is modulated by changing the blade authority limiter in flight. To do this you have to switch to the props using [ ] and then left-click on the blades.
• At speeds over Mach 5 the authority limiter of the blades is set to 0.

 

 

Spinner rushes into a new dawn approaching Mach 5

 

Spinner accelerates past Mach 5 while still climbing.