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21
One thing that did get my attention was the notation on one of Shawyers slides, #18, showing he introduced "piezoelectric elements" near the small end of the Ver. 3 frustum. What the hell is that? An introduction of Mach Effects from Woodward's research? Aimed at the likely static electric field in a TEXXX mode? If so, that fits into things I have been thing about induced quantum spin in an electric quanta to create transient mass.

But that's not what Shawer proposes.

As far as Tajmar inviting Shawyer, he's been in discussions with Shawyer as long as I have been following this. Appearing to teach/discuss with a bunch of sharp students doesn't surprise me at all.

Bob,

The piezoelectric elements are used to lengthen the cavity.

When an EmDrive does work, the photon wavelengths increase to represent the enery loss to that gained by the accelerated mass.

To keep the cavity resonant with longer and longer wavelength photons, the cavity length needs to continually increase. That length increase is done via the piezo elements pushing the small end plate further from the big end plate as the cavity stored photons lose energy to support the increasing KE of the accelerating mass.

Only required for very high Q cavities.

To do this requires the EmDrive to be fed with pulsed RF. See attached.
22
And yes Dragon had some issues that could have been life threatening as has been accounted for in books and articles.
Must have missed those; which books and articles?

For example,

http://www.latimes.com/business/la-fi-spacex-trouble-book-20180316-story.html


The stuck valve problem was not life-threatening. It was solved long before the spacecraft got in any real trouble.


How is losing control of your vehicle in an environment like space for 4 or 5 hours not life threatening? There was a real chance their fix wouldn't work.


What is little reported is that one of four RCS quads was fully operational, from the moment Dragon separated from Falcon 9 v1.0, with a second one being partially operative (one RCS thruster failed on the second quad).
Together they had enough control of the spacecraft to maintain attitude.


However, mission rules required all four quads to be fully operational before Dragon could attempt to approach the ISS.


But, Dragon was capable of doing the de-orbit burn with those two quads alone. In fact, that would have been the plan had the attempts, to activate the other two quads, been unsuccessful.


The rush to fix the problem was not due to attitude problems (Dragon was holding attitude just fine), but due to the need to do an orbit-raising burn.
Without that burn Dragon would have had no chance to reach the ISS. De-orbit would have been necessary.
But the entire episode never was potentially life threatening, had a crew been on-board:
- The vehicle was holding attitude
- The vehicle was capable of controlled de-orbit
- Solar arrays were deployed and sun-tracking
- Vehicle ECS was working fine.
- Vehicle comms were working fine.
23
Bob,

Roger's data, not mine.

Do you find it interesting that Martin Tajmar apparently invited Roger to Dresden so to teach his team and himself how to design and build EmDrives and how to measure the acceleration result?

As for proof, it seems we have at least a 2 horse race between Martin's team and myself to do the 1st public rotary test rig demo and video. Must say I'm a bit jealous Roger spent time with Martin and his team. He never did that with me. For sure Roger gave them a few breadcrumbs not in the power point that will accelerate their efforts.

Don't believe Roger will be doing any public demos, as his UK MoD partners are not that way inclined. So it seems he is reaching out to others and basically teaching them how to design and build gen 1 devices, plus how to measure the accelerative force they generate, using either his static spring and scale method or the rotary method. This alone should help DIY replicators to build fairly simple spring and scale test rigs. That is a major step forward.

As for the PPT, there are several critical shares in that document that have not been shared before. Probably only noticeable to DIYers who have some idea as to what is happening and why.

Also notice the thrust bandwidth is much less than the Q bandwidth. Freq control is shown to be very critical and is why I developed the tech to use reflected power to sync the freq to a changing cavity resonant freq. However if the DIY build uses a circulator that dumps reflected power into an open port, well then the build neeeds to use an internal to the cavity E field probe as Roger uses.

So for a informed DIYers, there is a lot of new and very useful info in the PPT.

BTW the Kmn in Roger's equations is, for TE01x mode, 0.819894. It changes for each mode. This is the basis for Roger's TE01x mode, rule of thumb, cutoff dia = external wavelength / 0.82. There is an equation that generates it based on freq and excited mode Bessel value.
All talk and no data is a big problem.

Phil, I'd like nothing better than to see a rig performing well out of the noise. But we never see anything except for those folks who have actively posted their results for all to see.

Dave Distler made a good first effort but it was not conclusive. Since he turned rig over to a private company to evaluate, nothing.

Jamie has been doing real science. Testing and improving. I know, I saw his rig up close and personal and was extremely impressed. But as of yet he hasn't published his test results.

One thing that did get my attention was the notation on one of Shawyers slides, #18, showing he introduced "piezoelectric elements" near the small end of the Ver. 3 frustum. What the hell is that? An introduction of Mach Effects from Woodward's research? Aimed at the likely static electric field in a TEXXX mode? If so, that fits into things I have been thinking about, induced quantum spin in an electric quanta to create transient mass.

But that's not what Shawer proposes.

As far as Tajmar inviting Shawyer, he's been in discussions with Shawyer as long as I have been following this. Appearing to teach/discuss with a bunch of sharp students doesn't surprise me at all.
24
General Discussion / Re: Moon Day 2018
« Last post by William1969 on Today at 07:36 AM »
A phenomenon? Hopefuly!
I'm having a friend over on the weekend, he's bringing over his telescope, I'm prepping the food. Although I have to say, I am a little disappointed, that the Moon Day falls on a Saturday and not a Monday.
25
ESA Launchers - Ariane, Soyuz at CSG, Vega / Re: ESA - Vega Updates
« Last post by SciNews on Today at 07:36 AM »
Edited version of the first hot fire test for P120C development model
26
Blue Origin / Re: New Shepard UPDATES thread
« Last post by woods170 on Today at 07:18 AM »
Forgive me for sounding naive or obtuse, but... how can Bezos have not seriously discussed the price of a ticket to ride his company's suborbital space tourism vehicle?

Less than two months ago Bezos said something very similar about the ticket price:

https://spacenews.com/blue-origin-plans-to-start-selling-suborbital-spaceflight-tickets-next-year/

Quote from: Jeff Foust
Even the company’s billionaire owner has not disclosed details. “We don’t know the ticket price yet. We haven’t decided,” said Jeff Bezos in an on-stage interview May 25 at the National Space Society’s International Space Development Conference in Los Angeles.

The answer to your question is: Jeff Bezos will discuss the ticket price when he is...
Quote from: Maverick
...g*ddamn good and ready. You got that?!
27
Cosmos 2519 doesn't appear to be matching the Cosmos 2521 orbital altitude:

Jul 15.823    97.855 deg      94.076 min     337-610 km    295 deg
Jul 16.541    97.848            93.778           312-606          295

Maybe it will be lower that C2521 to give the orbital planes a chance to drift close over time?   But apogee needs to come down first.
28
We should still figure out how bad can it be in dry vehicle mass and specific impulse to still be reasonably able to meet near term goals. Tonnage to mars by 202X. I assume some of this discussion could be found scatteres about in other threads. I intend to find some of that for quoting here tomorrow.
29
Commercial Space Flight General / Re: Orbex
« Last post by Steven Pietrobon on Today at 06:31 AM »
Would anyone have the knowledge to say what kind of picture it paints to have propane as a propellant in this vehicle and if we could begin to guess what the performance of the engines could be?

Comparison of kerolox, methalox and propalox.

Propellants  MR   dp (kg/L)  ve (m/s) Id (Ns/L)
O2/CH4       3.6   0.8376     3656     3062
O2/C3H8      3.1   0.9304     3613     3362
O2/RP–1      2.8   1.0307     3554     3663
HTP/RP–1     7.3   1.3059     3223     4209


Propalox is basically between methalox and kerolox. Has better Isp than kerolox, but worse then methalox. Density is however better than methalox, but worse than kerolox. Impulse density is better than methalox, but worse than kerolox. I've also added my favourite combination, keroxide, which has the worst Isp, but the best impulse density, making it a great first stage propellant.
30
Blue Origin / Re: New Shepard UPDATES thread
« Last post by tyrred on Today at 06:23 AM »
Forgive me for sounding naive or obtuse, but... how can Bezos have not seriously discussed the price of a ticket to ride his company's suborbital space tourism vehicle?
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