Sand Shark AH-1F Cobra V2
Rebirth
Since the 20' hard autorotation suffered by the Len Mount/Vario Sand Shark Cobra at the 2020 IRCHA (seized motor), the heli had been gathering dust while my other interests took me elsewhere. I decided to pick up where I left off and replace the power train with a more powerful KDE700XF-445. The previous 810mm blades were too short for a heli this size and weight, requiring close to 9 degrees of pitch to hover. All the animatronics in the nose section didn't help with the weight either. FYI, this heli features 16 servos within. As a result, the blades are replaced with the longer 920mm Helitec. A new power plant and larger blade disc need a new gear ratio, requiring several tries with spur gears of various teeth-count before I found the optimal combo (12T). Here are the new stats:
Flight weight 29 lbs, Headspeed 1050 rpm, hovering at 7 degrees, 12S 6500mAh, Current 41A, Motor temp 175F.
Here's the maiden tuning flight. Let's test out the new native video streaming feature of this site:) Well, it turned out my 2:50 minute video didn't go through because there's a 400MB size limit here. I had to re-encode my video to low bit rate and try again. Let's see...
Feedback for Mike Kranitz:
My heli (1/6 Len Mount AH-1F Cobra) doesn't fit into any of your predefined filter categories, hence cannot be tagged for searchability. I suggest you provide a free form tagging box for models that aren't predefined.
13 Comments
Hi Patrick, we will up the size limit on videos. As for posting, we have an “Other Scale” category under which you can choose Len Mount (but not the specific model).
Hey Patrick, we bumped the upload limit and it appears that you've taken full advantage! This video looks great! Of course, the subject matter helps. ; )
I understand native video streaming adds to the server expense. But I think it's a crucial feature to reduce usability friction. Hope you negotiated a good deal with a CDN such as Akamai:) Alternatively, you could allow embedding FB video, where most scale videos are already hosted.
Often overlooked but always appreciated!!
That looks excellent Patrick
You do great work Patrick !!
very Realistic wow
Very nice machine !
Motion including arms is awesome, I find it realistic. Must be very visible in flight. Well done!
It was a static display project, I've never flown it with the outboard passenger. His seat- the ammo bay door is supported by 2 tension cables, therefore not a rigid platform. I'm afraid he'll be bouncing up and down during flight, too risky.
How heavy is this bird now?
29.5 lb flight weight.
Nice build, specially the CG optimized Lipo position. Impressive features at the front gun.