Agree 100%!

Cheers :)

It's definitely been useful in getting things lined up and sized correctly.

Cheers!

Cheers! :)

Thanks Luc! I hope we get more than one flight out of it. Actually I'd be happy with even one flight. :)

Thanks! ... not long now until the launch so I am panicking a little bit, there is still so much to do.

Thank you for following along. :)

Cheers! Yup it's been a few years since we've flown it. Fun times :)

Cheers, thanks for the tip.

The current plan is around 10th August or so.

😮😮

This is a really good question, and it was one of the options we explored when designing it. When you have a look at the geometry of that setup and where the sustainer fins extend to, there wouldn't have been enough clearance for the fins over the entire range of possible positions of the fins. The size of the sustainer fins is fixed as the sustainer is already built. In order to get the full clearance you would have had to offset the the hexagon away from each of the booster segments. We compromised a little and the hexagon isn't a true hexagon three of the sides are shorter than the other 3.

@@AirCommandRockets Ah right, I forgot that it's not a true hexagon. (I had to watch the video in two part). Thanks for your answer!

No, the edge will stay as is. In the whole scheme of things this makes very little difference on the booster. If it was on the sustainer than we would probably streamline it.

@@AirCommandRockets Understood. Great job as usual though.

We haven't needed to replace it yet. I'd say we've cut perhaps 10 linear meters with it so far and it still looks fine.

Some paint may rub off during staging.

Yes this is correct. I think from the tests we did the booster segment increases about 1-2mm in circumference so let's say 0.5mm in diameter. The sustainer will also increase slightly , perhaps 0.3mm? There is about 1-2mm clearance for the sustainer between the booster segments. So yes a squeeze when pressurised and under acceleration which is good, and by the time of staging we should be back to the right clearance. The ring does have a little bit of flex under those loads so I am hoping we should be OK.

Yes, the loads on this ring are enormous. I hope even as is it is now that it is strong enough. You have a 2m long lever (the portion of the sustainer above the ring) trying to force it's way sideways during acceleration especially if the rocket has any kind of angle of attack which it will have. With the acceleration ~50G just before staging imagine the amount of force on that lever if say the rocket has a AOA of just 5 degrees and air speed of 360km/h pushing on that. Saving a few grams here isn't significant in terms of performance as the booster produces about 1 ton of peak thrust. The weight forward on the rocket also helps keep the rocket stable. Another way to look at it, sit on a bullet train and stick a 2m piece of wood out the window and angle it at 5 degrees from the direction of travel. Now hang on to it while the train gets up to 360km/h in about 1.1 seconds.