August 2011 Archive

G12 & G13 test – Aug 10

8/10/11

Don and Dudu took the G12 and G13 rokkakus with the new taped construction to Crown Beach for another test. They used a telephoto camera mount to take video with a GoPro from one of the lines and from the ground and put Joe’s superlight mount on the back of one of the kites.

Modified lens on GoPro

8/9/11

The non-fisheye lens on the GoPro is ready for testing on the lifting kites. Here Don hooks it up to the large monitor in the office. In these photos the camera is recording while projecting what it is recording on the big screen. Nalani and Max are visiting.

Rok G12 & G13 test – Aug 5

8/5/11

At Crown Beach. Don flew both the G12 and G13 design rokkaku kites with the new taped construction. He used a half of a plastic toy world globe and a 55mm UV lens filter to create a protective camera housing.

Superlight GoPro mount

8/5/11

This is intended to be used with the rok kites. Mount weighs 26g and articulates through about 90 degrees. Bare camera weight is around 100g.

Betsy note: our very lightest stock housing + mount weighs 111g. Often, the mounts we use are even heavier. This is not a big problem for the larger kiteboat kites, but it is a significant amount of weight for the lifting kites, as our current roks weigh less than 600g. Joe’s housing is not waterproof, but it should allow us to protect and position the camera on the kite without adversely affecting the kite’s balance.

ROK G13 test – Aug 4

8/4/11

Test:
-Weight: 575 g
-Seam construction used 50mm cover tape inside out
-Bladder 2mil
-Wind: 10-20 knots
-Crown Beach

Conclusions:
-Wind was too gusty for this size, which is 3.4m
-Flutter on one side of bottom edge
-Bridle points need to be non-floating, for fast inflation
-Strut ends also need to be non-floating

Rok G12 – fully taped construction – test Aug 3

8/3/11

This was the first test of the new construction, which includes cubic 50mm tape inside and out and 25mm double-sided tape.

We inflated the kite to 5psi. We tested over 2.5 hours at Crown Beach, in 10-knot winds. The flight was stable, with a line angle at 45-50 degrees. We taped a GoPro to the line and used a 100m 1.6mm line.

Betsy note: bottom photos show the G12 kite seams in the shop prior to the test.

Boat weights – K2 & Kitefoiler

8/2/11

Today we weighed K2 to check its actual weight against our estimates. With both floats, the center hull, both beams, all bulkheads and bonding, and both cassette boxes, K2 now weighs 228 kg (503 lbs). This is about 45 kg more than our calculated estimate, and 18 kg more than the highest individual estimate (everyone guessed before we weighed it). The higher weight is not ideal, but we’re still on track to deliver a completed boat that weighs less than 400kg. We also weighed K2 with the hatch covers in a box on top of the boat–that added 25 kg, for a total of 253 kg. We also weighed the trampoline net, which was 3 kg.

For comparison, we also […more]