I've been doing some reading lately with the goal of building some more NPWs for the upcoming season.
I've decided to build a NPW21 I think, though there is no good "build plan" for it, just a collection of threads.
Amongst all the reading I found out about the "Z-bridle" which links your power and brake lines to provide a constant brake bias when the brakes are slack. I thought that sounded simple and quick to do and fitted it onto my 1m NPW.

Well I took it out flying today and the difference is huge. In high, gusty winds (which are my NPW-flying winds) I regularly had spontaneous reversing of the kite in a gust. For some reason, the Z-bridle cured this and seems to have made the kite more stable as a whole, probably due to maintaining a consistent airfoil shape. Now in a gust it will accelerate and pull instead of reversing, collapsing and bouncing around. The best thing is you still retain full brake control, you just don't have to hold the brakes on all the time to shape the trailing edge. I am going to have to try it on a bar now, I think without the fiddling with brake bias it might work well!

Trying to teach my wife to fly power kites before, she could not get the hang of the NPW at all. Today she was able to keep it in the sky for several minutes at a time despite bad winds, and commented on how it was "way easier to fly"

Anyone else Z-bridle their NPWs? I saw no weakness introduced by doing so, only gains, especially for the new flyer. I know Nasa Stars are bridled similarly to make them a 2-line. I wonder why this is not part of the standard NPW9b plans?

I had to sit and try to remember how it was before I started using PKD handles and how it was to fly the NPWs on regular handles. Got to say it was a lot of work and trying to keep it in the zone was next to impossible.
Using the Z bridle on the Susan Specials didnt help much, as the size of the kite had a bit to do with it working or not. Might be why the Born Kites(nasa star) are only 4 sizes.
I spent a bit of time with Susans kites trying to make 2 line kites out of them with no success, with the grand idea of using PKD handles.
By adjusting the brakes with the handles until the kite is operating as a 2 line kite I can use the handles to apply the brakes. A win win situation.
The Z bridle is right on or a bit to much or not enough with the born kites, not sure how you can have one size z bridle and make it work on 4 different size kites.

I would think the born kites would be a great way to introduce a newbie to the wonderful world of Nasa wings as they are easy to fly on a bar or handles, long or short lines. Susans kites are for those that are a bit more knowledgeable in the kite itself and have more ability to fly kites. Another key is that you have to be able to "work it", you just dont pull it out of the bag and show off your lack of skill. You actually have to develop some skill to fly them. To fly them with any proficiency is going to take a lot more time to "work it".
I like both kites and enjoy them a lot. To play around and help others play, it the born kites. If I want to light it up and turn on the power, well it has to be with Susan.:D besides she know a great place to eat alligator.
Of course this is my own findings with the 2 kites.

I use a "Z" bridle on all my NPW kites from 3m to 11.5m and they work a treat! They don't work so well on the NPW 9b due to the nose on that model needing more brake control but the NPW21 is a more stable kite and is more suited to a "Z" bridle.

Here is a bit of vid of my 3m NPW21 (with Z bridle fitted) I took the other day, wind was a bit variable from just enough to get it in the air to picking up and generating a bit of pull. You'll see the nose does tuck at the beginning but it's due to the low wind and a slight brake input brings it back up.

One other thing I find with the Z bridle is that I put a knotted line on the Z bridle to allow me to adjust the brake line length (bridle side). Obviously too short and it will back stall, too slack and you can fly it as a normal four line with constant input from the handles. There is a fine line, I find the sweet spot does in fact mean the kite does not fly quite so high up to the zenith due to the brake pressure but it's not much and a compromise I'm happy with.

I will have to try the z bridle when it starts to cool off some. Still very hot and not a lot of wind.

Susan (npw goddess)

Bigkid, those PKD handles look awesome for NPW flying. With regards to the size of the Z-bridle, I'm not quite sure what you mean as I made my bridle on the fly out of some spare bridle line... I started with the bridle fairly long, brake and Q-point lines equal in length, and then moved the Z-point (as I feel like calling it) up and down the bridle until the kite flew with an upwards pull and no luffing. Ended up requiring about 2 inches more Q-point than brake, I think.

BigE, that is a well behaved NPW for sure.
I forgot to mention that in my first post, I also noticed that once the bridle is set up to a point where the nose won't collapse on the 9b, it will no longer reach the zenith. To me that is also a plus as my winds are very gusty, and parking at zenith invariably leads to overflying as the wind drops or shifts. Then I end up trying to wear the kite as a hat. So parking a little lower is good for me. I guess I did lose the option to snap the brakes full off and then draw them back in to catch wind during lulls, but the stability boost far outweighs that for me.

NPW flying will always require some finesse and the ability to use the brakes for more than braking, I think. I still used them heavily when flying on Z-bridle, to extend the edges of the window, to reinflate the nose after being crushed by crosswind gusts etc... perhaps with a bar, these could be accomplished by simply pulling the bar in to flare the brakes. Have you ever flown NPW on a bar?

Off the Z-bridle topic, I think it was your thread on another forum all about the 21 (I recognize the pirate kite). I would like to build a 5m NPW21 much like it, but your thread wandered so many different ways, to C-bridles, rigid struts etc... do you have any sort of plan for the "vanilla" 5m 21? I downloaded a spreadsheet from that thread, but the mix of languages in it was confusing to say the least, without a bit more documentation. PM me maybe?

With regards to a bar, I've tried a four-line de-power on an NPW 9b and could not get it to fly properly, that was before I started using a Z-bridle tho. I've also tried a Ozone turbo bar which does work. Peter Lynn did the "C" Quad bar which allows you to rotate the bar to increase / decrease the brake line pressure. Your Z bridle difference between brakes and Q-point sounds similar to where I ended up with mine, but that distance is size dependant.