Messages in AirborneWindEnergy group.                           AWES14440to14489 Page 184 of 440.
Group: AirborneWindEnergy Message: 14440 From: dougselsam Date: 9/15/2014
Subject: Re: why does a sailplane have a larger wingspan?

Group: AirborneWindEnergy Message: 14441 From: dougselsam Date: 9/15/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14442 From: dave santos Date: 9/15/2014
Subject: Re: why does a sailplane have a larger wingspan?

Group: AirborneWindEnergy Message: 14443 From: dave santos Date: 9/15/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14444 From: dougselsam Date: 9/16/2014
Subject: Re: why does a sailplane have a larger wingspan?

Group: AirborneWindEnergy Message: 14445 From: dougselsam Date: 9/16/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14446 From: Joe Faust Date: 9/16/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14447 From: dave santos Date: 9/16/2014
Subject: Re: why does a sailplane have a larger wingspan?

Group: AirborneWindEnergy Message: 14448 From: dave santos Date: 9/16/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14449 From: dave santos Date: 9/16/2014
Subject: 22m2 PL Pilot-Lifters arrive in Austin

Group: AirborneWindEnergy Message: 14450 From: dave santos Date: 9/16/2014
Subject: SS Kite bid to conquer Mongolia

Group: AirborneWindEnergy Message: 14451 From: dave santos Date: 9/16/2014
Subject: Makani Confidential (misc. notes)

Group: AirborneWindEnergy Message: 14452 From: dave santos Date: 9/16/2014
Subject: Cloud water harvest and pressurization by high-altitude kites

Group: AirborneWindEnergy Message: 14453 From: dave santos Date: 9/16/2014
Subject: Snow avalanche mitigation by kites

Group: AirborneWindEnergy Message: 14454 From: Rod Read Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14455 From: joe_f_90032 Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14456 From: joe_f_90032 Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14457 From: dougselsam Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?

Group: AirborneWindEnergy Message: 14458 From: dougselsam Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14459 From: Joe Faust Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?

Group: AirborneWindEnergy Message: 14460 From: dougselsam Date: 9/17/2014
Subject: Anyone with Engieering Knowledge on list?

Group: AirborneWindEnergy Message: 14461 From: dave santos Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14462 From: Joe Faust Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14463 From: dougselsam Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?

Group: AirborneWindEnergy Message: 14464 From: Joe Faust Date: 9/17/2014
Subject: Effect of the Electrical Energy Conversion on Optimal Cycles for Pum

Group: AirborneWindEnergy Message: 14465 From: dave santos Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?

Group: AirborneWindEnergy Message: 14466 From: dougselsam Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14467 From: dougselsam Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?

Group: AirborneWindEnergy Message: 14468 From: joe_f_90032 Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?

Group: AirborneWindEnergy Message: 14469 From: dave santos Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14470 From: dave santos Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?

Group: AirborneWindEnergy Message: 14471 From: dave santos Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?

Group: AirborneWindEnergy Message: 14472 From: joe_f_90032 Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14473 From: dave santos Date: 9/17/2014
Subject: Testing PL Pilot-Lifters for AWES Duty

Group: AirborneWindEnergy Message: 14474 From: dave santos Date: 9/17/2014
Subject: Japan's Interplanetary Kite-craft- IKAROS

Group: AirborneWindEnergy Message: 14475 From: joe_f_90032 Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?

Group: AirborneWindEnergy Message: 14476 From: dave santos Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?

Group: AirborneWindEnergy Message: 14477 From: joe_f_90032 Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?

Group: AirborneWindEnergy Message: 14478 From: dave santos Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14479 From: joe_f_90032 Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14480 From: dave santos Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14481 From: dave santos Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14482 From: dougselsam Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14483 From: dave santos Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

Group: AirborneWindEnergy Message: 14484 From: dougselsam Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?

Group: AirborneWindEnergy Message: 14485 From: dave santos Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?

Group: AirborneWindEnergy Message: 14486 From: Joe Faust Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?

Group: AirborneWindEnergy Message: 14487 From: benhaiemp Date: 9/17/2014
Subject: Re: Kite-Dome and Kite-Tower Integration by Tri-Tether

Group: AirborneWindEnergy Message: 14488 From: dave santos Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?

Group: AirborneWindEnergy Message: 14489 From: Rod Read Date: 9/17/2014
Subject: Engineers solve problems



Group: AirborneWindEnergy Message: 14440 From: dougselsam Date: 9/15/2014
Subject: Re: why does a sailplane have a larger wingspan?
"To reduce induced drag relative to lift,...takes the same minimum amount of power to maintain level flight" ***Sink rate, glide ratio depend on mass only? You think a 1000 lb sailplane has the same sink rate as a 1000 lb Cessna?  My information says a sailplane may have a glide ratio of 50:1, whereas a general aviation powered airplane has a glide ratio of maybe 12:1?  How could one then say the amount of power required to maintain level flight is dependent only on the mass of the airplane?  It's looking to me like you're posting more untrue statements.  Your answer explains why sailplanes are not biplanes, not why sailplanes require more wing for the same weight.
Group: AirborneWindEnergy Message: 14441 From: dougselsam Date: 9/15/2014
Subject: Re: "power to keep 1 kg aloft"
You're an idiot who cannot maintain a conversation thread.  You know nothing.  Amazing how you go on.  Sorry I cannot entertain you anymore,
Group: AirborneWindEnergy Message: 14442 From: dave santos Date: 9/15/2014
Subject: Re: why does a sailplane have a larger wingspan?
The Cessna has more induced drag for the same mass than your hypothetical glider. That's why its glide sink rate is higher, because its using up its same ration of potential energy faster, by its relative inefficiency. The glider is not far behind. In sub-orbital HTA powered flight, "what goes up, must come down".

Biplanes and bullets are red herrings. This is about why a sailplane has a larger wingspan, and my answer is standard aeronautical engineering knowledge. Your ("zero-energy") view is un-physical.


On Monday, September 15, 2014 5:29 PM, "dougselsam@yahoo.com [AirborneWindEnergy]" <AirborneWindEnergy@yahoogroups.com
Group: AirborneWindEnergy Message: 14443 From: dave santos Date: 9/15/2014
Subject: Re: "power to keep 1 kg aloft"
You do not "entertain" me. I merely volunteered to diligently correct your technical bloopers and poor Netiquette. Others wanted you banned for spreading "intentional stupidity" with regard to engineering science (as well as abusive anti-social manners). I think you can learn basic AE and social virtues, if you choose to, and you cannot easily convince me you can't (a formal psychiatric diagnosis would be required).

Remember, this is not a chat-room. Go elsewhere if you are done with the topic, and just want to "maintain a conversation".


On Monday, September 15, 2014 5:31 PM, "dougselsam@yahoo.com [AirborneWindEnergy]" <AirborneWindEnergy@yahoogroups.com
Group: AirborneWindEnergy Message: 14444 From: dougselsam Date: 9/16/2014
Subject: Re: why does a sailplane have a larger wingspan?
"its glide sink rate is higher, because its using up its same ration of potential energy faster" *** using more power to stay aloft - you were wrong - as usual.  Every single thing you post really is wrong - amazing.  Various sink rates for various airplane designs of the same weight are due to the various amounts of power required to keep these various types of airplanes aloft, though they may have the exact same weight.  This proves your assertion that there is a certain amount of power used to keep a given weight aloft as being 100% wrong, 100% opposite to reality.  And for the record, I do not care if you succumb to whatever OTHER idiots who know nothing about anything want me "kicked off" this venue - it is a waste of my time.  If you had a weak motor and wanted to craft a model airplane that could remain aloft using the weak motor, what design of craft would you build?  You'd choose a design with more wing area so it could remain aloft using less power.  There IS NO certain amount of power required to keep 1 kg aloft, as any 1 cubic meter helium balloon would show you, holding 1 kG aloft using NO power.   A model sailplane would use SOME power and a model fighter plane would use MORE power.  But then, I guess, as an "aviation expert" you SHOULD know all this in your sleep.  Duh.
Group: AirborneWindEnergy Message: 14445 From: dougselsam Date: 9/16/2014
Subject: Re: "power to keep 1 kg aloft"
" I merely volunteered to diligently correct your technical bloopers and poor Netiquette. Others wanted you banned" ***You are wrong.  Diligently wrong.  Go ahead and "ban" me.  It will be your best chance at gaining a footnote in the development of AWE.  "Yes there was one guy who tried to explain things to the morons, but they banned him."  Typical.  Who the hell cares.  Why don't you check on Altaeros and see if they've "quietly gone away" yet.  :O..............................
Group: AirborneWindEnergy Message: 14446 From: Joe Faust Date: 9/16/2014
Subject: Re: "power to keep 1 kg aloft"

Specific-system dependent?

Have AircraftSystem-A be trimmed for level flight in smooth airs. Note the power being expended for that situation. Divide that power by the mass in kilograms of that specific system; the result would be the power cost per kilogram for that circumstance.




~ 
Group: AirborneWindEnergy Message: 14447 From: dave santos Date: 9/16/2014
Subject: Re: why does a sailplane have a larger wingspan?
Doug,

The "zero-power" HTA flight bluff has failed. You cannot hide behind LTA or long wings to explain-away a glider's power need. A low glider sink-rate indicates flight efficiency, not buoyancy (a function of density).

The answer given you is correct- Sailplanes have longer wingspans to reduce induced drag. They require (non-zero) power (from height or rising air). The minimum theoretic power need was calculated for you. The inescapable real-world power requirement is the sum of the ideal minimum power required, plus the power to overcome real-world drag. The glider merely has less drag than a Cessna. Performance gliding is a luxury sport, comparatively, with increased cost for a lower drag airframe.

You openly asked for support for your view, but no rocket scientist on this list is came to your rescue (you have alienated or driven-away most of them by years of terrible Netiquette). You will not find independent expert support elsewhere for your incorrect physics. More ranting will not help. You should care that your "intentional stupidity" (antisocial behavior) and lack of positive progress limits your prospects in AWE. You are about to left behind by events.

Study the nice flight-principles link provided. It teaches correct flight physics in a well-crafted lesson,

daveS




On Tuesday, September 16, 2014 7:19 AM, "dougselsam@yahoo.com [AirborneWindEnergy]" <AirborneWindEnergy@yahoogroups.com
Group: AirborneWindEnergy Message: 14448 From: dave santos Date: 9/16/2014
Subject: Re: "power to keep 1 kg aloft"
Doug,

I will consistently block you being banned, but not ban you on your request. Ban yourself, if you really want. The theory is that you fantasize and claim wrongful concept censorship, as if you were a misunderstood genius, when you are merely socially excluded by most wind power circles.

Instead, here you must forever face scaling-law, and like objections*, as your unmet AWES concept challenges. I can't remember you have ever addressed AWE drive-shaft scaling limits honestly, but always claim to lack the time and patience.

If you will not ban yourself, find good third-party references in support of your homespun aeronautical engineering ideas. Beat reeling parafoil baseline-data at small scale (200ft), to show progressive mastery of inventive AWE design. Don't be left behind,

daveS


* You rudely dismiss many due-diligence essentials as irrelevant to AWE, like FAA safety-reg compliance, soft wings, kite expertise, meteorological expertise, aviation expertise, etc..
Group: AirborneWindEnergy Message: 14449 From: dave santos Date: 9/16/2014
Subject: 22m2 PL Pilot-Lifters arrive in Austin
For the last few years we have followed Peter Lynn's progress in refining and scaling up his basic pilot-lifters. He understood the golden value of cheap lift for AWE, and these kites really are priced incredibly cheap. We look forward to continued unit scaling-up at low m2 cost, but more importantly, we expect large linked arrays of pilot-lifter units like these to first enable early utility scale AWES. The lifters come ready to stack, and also work side-by-side from loadpath arches. They will pilot-launch giant Mothra arches eventually.

kPower has taken delivery on a trial order to the Chinese manufacturer, in FAA colors (red and white), for varied testing from airspace-conspicuity to suspending WECS like looping power foils, and aerotecture experiments. A skin kite was included in the order to evaluate as a looper. These kites are capable of lifting humans in a good breeze, and we intend to carefully work out safe best-practices for major future aerotectural experiments. These are also the specific kites we have been waiting for to do AWEfest, but it took this long to get them.

Ed is ready to go, and if he is reading this, I suggest he fly them every which way with Austin regional kite experts like the Ortiz Family and Barry Ogletree (WhataKite). This is what daily progress in AWE R&D is like; the kites get bigger and better, our rigging and flying skills sharpen, and its fun. It can be hard to be patient with minor delays, but before too long, with hard work and skill, amazing things happen.

kPower's specific rig designs with these kites are covered by CC 4.x BY NC SA.
 
Group: AirborneWindEnergy Message: 14450 From: dave santos Date: 9/16/2014
Subject: SS Kite bid to conquer Mongolia
From Peter Lynn's latest newsletter, regarding a kite-buggy rampage across Mongolia with SingleSkin wings; note the rave reviews of the latest design iteration-
-----------------------------

"...[Mongol] warriors could manage 80km/day with just 3 horses per, while Craig and Gavin are, rather cheekily, aiming for more than 90 km/day - 2800km in just 30 days- unsupported.

But they do have a secret weapon.

Which is latest generation single skin traction kites.

Michel Dekker ('foil kite designer for the Peter Lynn brand at Vlieger Op) has kindly shared the plans for his latest single skin kites with us here in NZ- and with sewing support, in particular from Perrin Melchior in Auckland, a range of sizes were ready - but untested - just in time for Craig and Gavin to take. Generally, "last minuting" like this is a recipe for failure, but single skin kites are so broadly functional and so forgiving that maybe this time it has not put the expedition at risk.

And these kites are fantastic - unbelievable even- especially the most recent simplified 'Trainer' model. They have all the standard single skin virtues.

Weigh almost nothing, are unburstable, unluffable, and ridiculously easy to fly, turn on their tips, and have more pull for size while requiring less wind than any other type of traction kite.

And, this is new, they also seem to be as good upwind as some specialist buggy foils.

Too good to be true?

Mongolia will be a perfect test for them in real world conditions..."
Group: AirborneWindEnergy Message: 14451 From: dave santos Date: 9/16/2014
Subject: Makani Confidential (misc. notes)
Deep in stealth mode, Makani offers few public clues to its inner drama. Three small notes-

- Whats up with the M600 claim that it will reach its "first power point" (generation cut-in) at only 4m/s, but Wing7's number is 10m/s? Is this a typo, or is there some technical explanation.

- One updated job listing (Technical Program Manager), but scant indication of a hiring push (the few older listings still look open).

https://www.google.com/about/careers/search#!t=jo&jid=66175001&

- They seem to have two options going forward; a full-on engineering debacle, or the accustomed silent-retreat*. The debacle scenario requires more turning-of-the-screw, but the retreat may have already begun, and we would have to wait for confirmations (like the M5 purge from promo content).

This is a very suspenseful tech story, if they really are hell-bent. We may have to pump our in-place informant network for an inside report, if GoogleX does not feed us real news soon.


* Makani has a pattern of slipped specifications (2007 10km altitude target), postponed milestones (market entry), and withdrawn ambitions (M5), without offering explanations.
Group: AirborneWindEnergy Message: 14452 From: dave santos Date: 9/16/2014
Subject: Cloud water harvest and pressurization by high-altitude kites

 A train of kites can in-principle raise a pressure hose to high altitude and harvest fog (cloud water) to supply flow.

The pressure of a water column 5km high is 500atm or 7,350 psi, which is suited for many direct high-pressure applications, including water-jet cutting of soft materials, driving refrigeration cycles, and high efficiency hydroelectric output.

The hose would be lifted in kite-stage sections, with higher pressure capacity lower down. Low pressure versions could save flying weight and maximize throughput. Such a system might be made mobile enough to fight wildfires or drought regionally.

No strong indication the idea is ultimately good or bad, but it has the virtue of relative simplicity, and its synergetic with supplying water for populations and irrigation.

CC 4.x BY NC SA
Group: AirborneWindEnergy Message: 14453 From: dave santos Date: 9/16/2014
Subject: Snow avalanche mitigation by kites
A kite system flying in clear winds above snow-capped mountains could flexibly deploy a wrecking-ball mass against dangerous snow accumulations, to preempt avalanche risk.

The system would compete against existing artillery and set-explosive methods, and resolve terrain access in novel fashion. Wind intermittentcy would not be a major limitation, since the system would usually have many chances to deploy before conditions become dangerous (dense pack shear-loaded over loose snow). The crane-work aspect would be powered in native form by wind, either by working the kite directly, or by a secondary WECS. The "wrecking-ball" could even be a winged pod for accurate impacts.

CC 4.x BY NC SA
Group: AirborneWindEnergy Message: 14454 From: Rod Read Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"

power to keep 1 kg aloft

This is dependant on the device as, both you enormous twonks point out. Stop the mute arguing please.
Hold the 1kg with your arm straight out, fly it on the back of a pigeon, hover it above a hair drier ... all the same?
What's the reference system?  Using bees to test this is cruel and should be ruled out.

That 17simpleflight.pdf has some VERY nice pictures. It's a great introduction. Even I got it.


The 1kg weight is "suspended" using lift (from downward deflected air mass and aerodynamic pressure difference) imparted to the supporting structure.
e.g. it increases the wing loading 1kg/area. It increases the airflow needed over the wing to maintain a vertical force equilibrium.(Only 1 set attack angle & glide ratio considered in this case) (slides 18 - 27)

To overcome the necessary
drag (air resistance and air momentum exchange)
and excessive lift (required for solid above earth position flight),
I'd use, tethering and an aerodynamic shape with a glide ratio. In our case. (lets call it,,, a kite maybe)

Depending on the glide ratio (=L/D) of the kite, angle of attack and wing air velocity ... more or less energy will be extracted to maintain the 1kg aloft. (see slide 42)

Even without some flight device there is the constant interplay of impulse, force.time the 1kg and support will have on each other.
Being supported by airborne methods implies the weight in a wing has to be in airflow, or it glides down to ground, assuming structural integrity (unlike exact kite case).

Our tether, using the momentum of the earth (large), is an efficient resource for this work. It enables a fluid energy exchange to support the kite wing with little operator onus or intervention. The earth does the work for us.

That's the frame of reference I think the original question was designed to ask.
What's our best resource to enabling maintenance of 1kg above the earth?

That's going to depend on kite size I'd say. And ability to match kite size to requirement.
Given a load-path flown arch kite can have trailing edge lines to a ground circle... We can devise systems to actively augment and reduce wing size and lift capacity by moving new arch sets up behind the leading arch on these trailing lines.

So much for lift....
How do we enable a spinning kite to glide like a modern turbine but with the precision of the black skimmer (slide 28) and relate maximal energy exchange to earth...?
Answers on a new forum post please.


Rod Read

Windswept and Interesting Limited
15a Aiginis
Isle of Lewis
HS2 0PB

07899057227
01851 870878
Group: AirborneWindEnergy Message: 14455 From: joe_f_90032 Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
Did not see link, so here is one regarding the document Rod mentions:


---In AirborneWindEnergy@yahoogroups.com, <rod.read@gmail.com
Group: AirborneWindEnergy Message: 14456 From: joe_f_90032 Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
Group: AirborneWindEnergy Message: 14457 From: dougselsam Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?
DaveSsaid "You will not find independent expert support elsewhere for your incorrect physics. More ranting will not help"  ***Take your own challenge: find an engineer who DISagrees with me.  By "engineer" I assume you mean someone who knows what they are talking about, implying that you are not that person.  I agree.  Ask any engineer, and the first thing they will tell you is holding a weight at a static position does not, on its face, require ANY power - zero.  Then if you are using deflected air to hold a mass at a position against gravity, a thrust equal to the weight must be maintained.  The thrust is based on momentum, which varies linearly with speed of deflected flow.  Since the ENERGY of that thrust varies with the SQUARE of the speed of that deflected flow, you can CHOOSE to reduce the energy transfer by deflecting a LARGER AMOUNT of air at a SLOWER SPEED.  The result is LESS POWER REQUIRED, trending toward that zero point, as wing area is increased.
I realize now that such simple and well-understood engineering facts are complete gibberish to everyone on this list.  You should all go to school.
If this is NOT gibberish to ANYONE, please reply to this, so we know there is at least ONE PERSON on this list who has taken Engineering 101.
Thanks
:)
Doug Selsam
Group: AirborneWindEnergy Message: 14458 From: dougselsam Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
To Dave S.: ***Take your own challenge: find an engineer who DISagrees with me.  By "engineer" I assume you mean someone who knows what they are talking about, implying that you are not that person.  I agree.  Ask any engineer, and the first thing they will tell you is holding a weight at a static position does not, on its face, require ANY power - zero.  Then if you are using deflected air to hold a mass at a position against gravity, a thrust equal to the weight must be maintained.  The thrust is based on momentum, which varies linearly with speed of deflected flow.  Since the ENERGY of that thrust varies with the SQUARE of the speed of that deflected flow, you can CHOOSE to reduce the energy transfer by deflecting a LARGER AMOUNT of air at a SLOWER SPEED.  The result is LESS POWER REQUIRED, trending toward that zero point, as wing area is increased.
I realize now that such simple and well-understood engineering facts are complete gibberish to everyone on this list.  You should all go to school.
If this is NOT gibberish to ANYONE, please reply to this, so we know there is at least ONE PERSON on this list who has taken Engineering 101.
THERE IS NO ONE PARTICULAR AMOUNT OF POWER REQUIRED TO KEEP 1 KG ALOFT BY DEFLECTION OF WIND.  IN GENERAL, THE POWER VARIES INVERSELY WITH WING AREA, TRENDING TOWARD ZERO AS WING AREA IS INCREASED.  PERIOD.  IF YOU CAN'T UNDERSTAND THIS, YOU NEED TO GO TO ENGINEERING SCHOOL.  IF YOU DISAGREE, PLEASE PRESENT A DEGREED ENGINEER TO REFUTE IT.  NOW I HAVE TO MOVE ON - IT IS NOT POSSIBLE TO HAVE AN ENGINEERING DISCUSSION IF PEOPLE ARE NOT UP-TO-SPEED ON THE VOCABULARY AND BASIC CONCEPTS IN ENGINEERING.
Thanks
:)
Doug Selsam
Group: AirborneWindEnergy Message: 14459 From: Joe Faust Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?
"on its face"   is a restriction that may need to be explicated carefully. I will let DougS explicate that matter. 

A case where work is done to hold a mass in static position in space: (thus power is being exhibited)::
I know that I cannot hold a mass at arm's length horizontal from my neck keeping the mass in static position in space while in standing position without burning calories. I have much experience with this matter; I wrap the exercise within a broader class of exercises that I call "control exercises" that I use to advance skills for jumping. 
The subset of exercises that holds my foot statically to my side in space is one in which I hold the foot for a full minute; then I relent and relax and let the foot come down from the static position.   But during the holding of the foot in static position, there are calories being burned in order to sustain the foot in the static position. Work is being done in that minute of hold; the amount of work done divided by the one minute gives a power figure for the exercise.
Isometric exercises ... hold masses fixed in position.

~JoeF
Group: AirborneWindEnergy Message: 14460 From: dougselsam Date: 9/17/2014
Subject: Anyone with Engieering Knowledge on list?
Regarding: "power required to hold 1 kg aloft" (an engineering oxymoron which amounts to a nonsensical question): Do we have any degreed engineers on this list?  Anyone else who understands this sort of stuff, and knows the answers and what these answers mean, besides me?  I guess what I'm asking is: "IS THERE ANY INTELLIGENT LIFE HERE"?  :) Please reply ONLY if you are KNOWLEDGEABLE and UNDERSTAND the topic.  It will be instructive to find out if there is "ANYBODY OUT THERE".  Thanks. :) Doug Selsam
Group: AirborneWindEnergy Message: 14461 From: dave santos Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
Doug,

I am an engineer who disagrees with you. "Zero" power and "near zero" power are wrong answers of yours.

The question is about the theoretic minimum power to sustain a kilo aloft by HTA flight. In the real world, of course, there are all sorts of added drag sources, and the minimum power ideal is not quite achievable.

No one is saying that one drag number fits all. That would be a fallacy like saying all HAWTs approach Betz to the same degree,

daveS


On Wednesday, September 17, 2014 9:10 AM, "dougselsam@yahoo.com [AirborneWindEnergy]" <AirborneWindEnergy@yahoogroups.com
Group: AirborneWindEnergy Message: 14462 From: Joe Faust Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
Doug, the generalization to full list cannot easily be proved either way; we have only posts; we do not have the status of the minds of the 180 members on the list. 
~JoeF
Group: AirborneWindEnergy Message: 14463 From: dougselsam Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?
"I cannot hold a mass at arm's length ... in static position... without burning calories. *** Try using a table, or place the mass on your leg while sitting.  A table typically uses no energy to hold up a weight.  Joe, you guys are revealing that you have no background in engineering.  You guys don't understand the basics, nor the relevant terminology.  You're all really way over your heads even trying to have such a discussion, and that apparently includes Roddy across the pond too.  I had no idea.  Sorry to break the news.  I guess education really DOES have value... Who knew?  Still waiting to hear whether there is anyone else on list who understands basic engineering.
Group: AirborneWindEnergy Message: 14464 From: Joe Faust Date: 9/17/2014
Subject: Effect of the Electrical Energy Conversion on Optimal Cycles for Pum
tip provided by PJ. Thanks PJ. ::



Source: https://lirias.kuleuven.be/handle/123456789/461949 

Title: Effect of the Electrical Energy Conversion on Optimal Cycles for Pumping Airborne Wind Energy
Authors: Stuyts, Jeroen ×
Horn, Gregory Mainland
Vandermeulen, Wouter
Driesen, Johan
Diehl, Moritz #
Issue Date: 2014
Publisher: Institute of Electrical and Electronics Engineers
Series Title: IEEE Transactions on Sustainable Energy
Abstract: Airborne wind energy harvesting offers an alternative to traditional wind turbines by flying crosswind cycles with a tethered airfoil. By reeling in and out the tether periodically, net electrical power can be generated. When looking for the optimal cycle to fly, one should optimize for maximal electrical power generation. However, the conversion from mechanical to electrical power was not yet included in the models. In this paper it is shown that by including an electrical energy conversion model into cycle optimization, the electrical output of the system increases and the acquired system can be used in a broader range of wind speeds. The approach is illustrated with experimentally verified models.
ISSN: 1949-3029
Publication status: accepted
KU Leuven publication type: IT
Appears in Collections:ESAT - STADIUS, Stadius Centre for Dynamical Systems, Signal Processing and Data Analytics
ESAT - ELECTA, Electrical Energy Computer Architectures
× corresponding author
# (joint) last author
Group: AirborneWindEnergy Message: 14465 From: dave santos Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?
Doug,

The answer is yes. If your memory was good, you could list several degreed engineers on the forum, some of whom you personally  slimed with ProfC insults (like Reinhart and Gabor). Others have clearly earned the title by carreer practice. Are you really a degreed engineer, as your message implies graduation is your merit standard?

You are the master of "Engieering" [sic] here,

daveS




On Wednesday, September 17, 2014 9:28 AM, "dougselsam@yahoo.com [AirborneWindEnergy]" <AirborneWindEnergy@yahoogroups.com
Group: AirborneWindEnergy Message: 14466 From: dougselsam Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
"Doug, I am an engineer who disagrees with you....The question is about the theoretic minimum power..." *** 1) You've changed the question; 2) You are not an engineer and you've already shown you have no grasp of engineering; 3) I'm asking specifically for actual engineers to answer, specifically not you. 

The original question was how much power it takes to keep 1 kg aloft, as though there is a standard amount of power required.  Or maybe it was erroneously stated as "energy".  (You guys don't understand how your posts contain multiple errors in each sentence - amazing level of nonsense)

The question was not "what is the minimum" which would have admitted there is not a single amount of power required, but that it must vary depending on configuration.  That would have acknowledged that it might vary toward zero under the right circumstances.  (many questions answer themselves if you think about it).  You guys didn't get that far.  You thought there is a standard amount of power required.  Nope.  There is a standard amount of THRUST, and the power to provide that thrust can approach zero as the area is increased, as I have amply explained about 10 times now.

The question was "how much power does it take?"  Anyway, you have already proven beyond a shadow of a doubt that you do not understand the subject and are NOT an engineer, so please STOP YOUR INCESSANT NONSENSE.  The only people you can fool are other stupid people.

I'm seriously trying to discern if there is any degreed engineer on this list.

I'd also settle for someone with no degree, but who understand the vocabulary of engineering, with a working knowledge thereof.  Anyone?
Seriously, does ANYONE grasp what I've been explaining for days on end now?
:)
Doug Selsam
Group: AirborneWindEnergy Message: 14467 From: dougselsam Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?
"Doug,The answer is yes. If your memory was good, you could list several degreed engineers"  ***Why did they not answer Joe's question then?  Dave S., I specifically have requested the actual people to answer, not you.  I think we've heard enough from you, and it is apparent you and Joe do not know the difference between thrust and energy, as one example.  Please stop your nonsense and lies now, K?  :)
Group: AirborneWindEnergy Message: 14468 From: joe_f_90032 Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?
Doug, did my explicated case have an error in it?  
Thanks, 
~JoeF
Group: AirborneWindEnergy Message: 14469 From: dave santos Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
Doug,

You are proving that you cannot find an engineer to support you; not here, nor out in the wide world. You have alienated all the engineers here with your combination of hype and "intentional stupidity". Engineering is intentional intelligence.

What you overlook is the HTA flight requirement for Thrust. A glider gets thrust from tapping rising air or height, a kite from its tether in opposing wind, and a powered aircraft from its engine.

Try this MIT link next:

 Theory of Flight

daveS


On Wednesday, September 17, 2014 9:53 AM, "dougselsam@yahoo.com [AirborneWindEnergy]" <AirborneWindEnergy@yahoogroups.com
Group: AirborneWindEnergy Message: 14470 From: dave santos Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?
Joe,

I ask you to help address Doug's question in the subject line directly, which is only about sailplane wingspan.

My answer was standard (to reduce induced drag). Do you agree with it?

daveS




On Wednesday, September 17, 2014 9:56 AM, "joefaust333@gmail.com [AirborneWindEnergy]" <AirborneWindEnergy@yahoogroups.com
Group: AirborneWindEnergy Message: 14471 From: dave santos Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?
Energy is power over time. Thrust is propulsion-force in powered flight.

Joe and I do know this.

Which question has Joe posed to engineers (that they do not answer)? We get many good answers off-Forum, that you are prevented from seeing, due to troll avoidance. You are not proving there are no engineers in our circle, but that your "intentional stupidity" has left you utterly isolated.

Joe and I are your last friends here, trying to cope with your apparent madness. Give us a break.


On Wednesday, September 17, 2014 9:54 AM, "dougselsam@yahoo.com [AirborneWindEnergy]" <AirborneWindEnergy@yahoogroups.com
Group: AirborneWindEnergy Message: 14472 From: joe_f_90032 Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
Sorry about the typo on author's name. 
Correct to 
Henk Tennekes
Hendrik Tennekes
Hendrik Tennekes - Wikipedia, the free encyclopedia

 




~JoeF
Group: AirborneWindEnergy Message: 14473 From: dave santos Date: 9/17/2014
Subject: Testing PL Pilot-Lifters for AWES Duty
Anyone interested is invited to suggest tests to add here, to add open value-
---------------------------------------

PLPL Testing Notes to kPower in Austin from KiteLab Ilwaco: 

Test the following while logging conditions, upsets, recoveries, and mishaps. Video data preferred-

Basic Flight Stability (endurance sessions)

Stacking (according to PL model)

Side-by-Side Flight from a CrossWind LoadPath (arch rig)
            Work out best leader lengths (to avoid cross-interference and modulate self-resonance)

Payload Capacity (measure directly, and loft WECS, test dummies, etc.

Looping Foil under FAA-compliant red and white 2-stack

2-Stack Conspicuity at 2000ft (with FAA approval and third party observation)

[add more]
 
Group: AirborneWindEnergy Message: 14474 From: dave santos Date: 9/17/2014
Subject: Japan's Interplanetary Kite-craft- IKAROS
Japan is predicted by initiated masters to soon play a major role in perfecting AWE, given that Japanese kite culture is unsurpassed, from traditional to futuristic practice. IKAROS is one far-out kite-

IKAROS - Wikipedia, the free encyclopedia
Group: AirborneWindEnergy Message: 14475 From: joe_f_90032 Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?
The subject line question is inadequate in itself, as it does not qualify "larger" for a discussion. One is teased to look at how that inadequacy is attempted to be cured by reading the body of the message under the inadequate subject line.   The curing is attempted by the poster by getting into 
"larger wingspan than a powered airplane of the same weight."

Even the expanded effort brings a "subject" with considerable challenge. Indeed one may have a sailplane of weight A and a powered plane with that same weight A, but the powered plane might have larger wingspan than the powered plane.  So, even the adjusted subject invites branching of answering.  Facing the  inadequate subject and the inadequate adjusted subject will result in confused answers teasing massage of some more refined subjects.  In the effort to get a refined subject we might find several interesting alternate subjects that seem to rub close to what might have been intended.  Confusion and fuzzy prose may be a rich mine for alternate subjects; willingness to discern matters in the dance would be helpful; then branching might enrich participants.  

     Here is one tease that just might be part of Doug's intention, not sure:   The item in focus might not be "wingspan" but maybe aspect ratio for given wing area.  Aspect ratio distinguishes sailplane of high performance from finesse of 3 for a primitive Rogallo hang glider. Let both be of same gross weight and wing area. Notice that airfoil and aspect ratio differ. Flight performance of the sailplane of, say, finesse of 30. will differ from the flight performance of Rogallo of finesse of 3.

Aspect ratio (aerodynamics) - Wikipedia, the free encyclopedia

 

Increasing aspect ratio, most else remaining constant, tends to reduce induced drag.

~JoeF 
Group: AirborneWindEnergy Message: 14476 From: dave santos Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?
Joe,
This is a question suited to a concise correct answer in order get back to RAD. If Doug wanted expansion of the question, you have him covered, at least.

A variation of this question is: Why does an albatross have a larger wingspan than a quail? One could write a book about the sea v. woodland environment, evolution, and so forth, or just invoke reduced induced-drag, to nail the flight physics bulls-eye,

daveS


On Wednesday, September 17, 2014 1:01 PM, "joefaust333@gmail.com [AirborneWindEnergy]" <AirborneWindEnergy@yahoogroups.com
Group: AirborneWindEnergy Message: 14477 From: joe_f_90032 Date: 9/17/2014
Subject: Re: why does a sailplane have a larger wingspan?
Correction of my prose: 
Given: "but the powered plane might have larger wingspan than the powered plane."
Correction, please, to intended:
    "but the powered plane might have larger wingspan than the sailplane."

Thanks, 
~JoeF
 
Group: AirborneWindEnergy Message: 14478 From: dave santos Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
Here's another simple way for Doug to see the correct answer-

A kilogram is the downward force of 10 Newtons in Earth's gravity field. 

An equal opposite upward force of 10N is required to balance downward force, to maintain 1 kg in level flight.

10N = 10W , which is the minimum theoretic-ideal power required to keep 1kg aloft.

Add real world drag forces to the 10W minimum, to get a realistic level-flight power requirement for a given 1kg aircraft.




On Wednesday, September 17, 2014 10:48 AM, "joefaust333@gmail.com [AirborneWindEnergy]" <AirborneWindEnergy@yahoogroups.com
Group: AirborneWindEnergy Message: 14479 From: joe_f_90032 Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
Newtons are not equivalent to watts.  So, some adjustment in the prose is invited.

~JoeF
Group: AirborneWindEnergy Message: 14480 From: dave santos Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
Whoops,

I meant Newton Meters/Sec^2

sorry for unintentional stupidity, but looking forward to getting it right.

--------- second try -------------------------


A kilogram is the downward force of 10 Newtons in Earth's gravity field of ~10m/sec^2. 

An equal opposite upward force of 10N is required to balance downward force, to maintain 1 kg in level flight. This force is created by deflecting air downward with a total force of 10N m/sec^2

10N m/sec^2 = 10W , which is the minimum theoretic-ideal power required to keep 1kg aloft.

Add real world drag forces to the 10W minimum, to get a realistic level-flight power requirement for a given 1kg aircraft.





On Wednesday, September 17, 2014 1:29 PM, dave santos <santos137@yahoo.com
Group: AirborneWindEnergy Message: 14481 From: dave santos Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
--------------- try number three! getting close... ---------------

A kilogram is the downward force of 10 Newtons in Earth's gravity field of ~10N m/sec^2. 

An equal opposite upward force of 10N is required to balance the downward force, to maintain 1 kg in level flight. This force is created by deflecting air downward with a motion measured in m/sec^2, in this case 10N m/sec^2, so the two forces cancel. The canceling force is 10N m/sec^2.

10N m/sec^2 = 10W , which is the minimum theoretic-ideal power required to keep 1kg aloft.

Add real-world drag forces to the 10W minimum, to get a realistic level-flight power requirement for a given 1kg aircraft.



On Wednesday, September 17, 2014 1:51 PM, dave santos <santos137@yahoo.com
Group: AirborneWindEnergy Message: 14482 From: dougselsam Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
"Doug, ...you cannot find an engineer to support you;..." *** Dave Lang and Neil Dennis both flagged your inability to use units correctly.  This reveals your recent statement that you are "an engineer" as one more lie, in a continuous string of lies and intentional misstatements, that are lost among all your unintentional and misinformed statements. 

You guys are 100% "out-to-lunch".  Most everything you say is either meaningless or misinformation.  The level of "debate" you attempt is childlike at best.  Sorry I just can't take the time to read all your crap or Joe's crap either.  I think an urge to create a discussion site for airborne wind energy was a great idea.  Joe does a good job of keeping the discussion site functional. Beyond that, you show every day that you are not equipped to PARTICIPATE in this discussion (different skillset than moderating a yahoo group), let alone a debate. 

Like I said, YOU are the one issuing the challenge.  I say the ball is in YOUR court.  Find an engineer who is willing to make a public fool of himself arguing with basic engineering knowledge, and let's hear from the engineer who disagrees with my explanation of power to keep 1 kg aloft.  Refresh: That explanation is that thrust (not power) is required to keep 1 kg aloft, and that the requisite thrust can be generated by using a lot of power for a small wing, or by using very little power for a larger wing, approaching zero power for a very very large wing, as long as the mass remains at 1 kg.
Go ahead, Ace, find the engineer.  Bring him here and show us how smart you are (again). 

By the way, getting the units wrong then claiming to be "an engineer" is like saying 2 + 2 = 5 then claiming to be a mathematician, or like humming the wrong tune in the wrong key and claiming to be a musician.  You are completely ridiculous in all you say, every day, and in every way...
Group: AirborneWindEnergy Message: 14483 From: dave santos Date: 9/17/2014
Subject: Re: "power to keep 1 kg aloft"
Sorry for the multiple posts, but small errors keep popping up. 1G = ~10 m/sec^2 without N.

-------------------- fourth try, *sigh*  ---------------------

A kilogram is a downward force of 10 Newtons in Earth's gravity field of ~10m/sec^2. 

An equal opposite upward force (lift) of 10N offsets the downward force, to maintain 1kg in level flight. 

The upward force is created by deflecting air downward at 10N m/sec^2, so the forces cancel. 

10N m/sec^2 = 10W , which is the minimum theoretic-ideal power required to keep 1kg aloft.

Add real-world drag forces to the 10W minimum, to get a realistic level-flight power requirement for a given 1kg aircraft.


On Wednesday, September 17, 2014 2:04 PM, dave santos <santos137@yahoo.com
Group: AirborneWindEnergy Message: 14484 From: dougselsam Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?
"Joe and I are your last friends here, trying to cope with your apparent madness. Give us a break." *** You guys: dumb, not engineers.  You lie. No you do not get a break.  Your postings are abhorrent.
Group: AirborneWindEnergy Message: 14485 From: dave santos Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?
Doug,

Joe and I are just doing our best. DaveL and Dennis also make bloopers. What makes us sane is the gratitude to stand corrected. You seem to lack this ability.

Note that you posted this sick topic without regard to the fact that DaveL has engineering knowledge and obviously follows the list. You seem to forget that he has critiqued you more severely than anyone, and that you have driven apart anyone besides Joe and me to "converse" with.

You are getting old. Focus on finally making a positive contribution to wind power, not on being a troll. You have not made a dent in utility-scale wind tech yet, so keep trying. Joe and I are not to blame if you cannot, but hope to help if you can,

daveS


On Wednesday, September 17, 2014 2:21 PM, "dougselsam@yahoo.com [AirborneWindEnergy]" <AirborneWindEnergy@yahoogroups.com
Group: AirborneWindEnergy Message: 14486 From: Joe Faust Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?
Not power over time, but power times time brings work back.
Group: AirborneWindEnergy Message: 14487 From: benhaiemp Date: 9/17/2014
Subject: Re: Kite-Dome and Kite-Tower Integration by Tri-Tether

DaveS,

 

Please have you more data or links about Kite-Dome?

 

PierreB
Group: AirborneWindEnergy Message: 14488 From: dave santos Date: 9/17/2014
Subject: Re: Anyone with Engieering Knowledge on list?
Joe, any other problems you see with 4th try?

Power-over-time seems OK to me-

Wikipedia "The integral of power over time defines the work performed."

Power (physics) - Wikipedia, the free encyclopedia
 


On Wednesday, September 17, 2014 2:43 PM, "Joe Faust joefaust333@gmail.com [AirborneWindEnergy]" <AirborneWindEnergy@yahoogroups.com
Group: AirborneWindEnergy Message: 14489 From: Rod Read Date: 9/17/2014
Subject: Engineers solve problems
Wow an exciting headline if ever you saw it...
But it just means get down to work slackers.

Problem: a pal on fb ... can't cycle up hills.
Solution: eyelash e-bike kites fold into turrets.

If you're tough enough
Test the wind
Take your ss kite rings, pegs, ladder and ss lift from your cycle pannier
Pin & fold bike to form tripod
remove front wheel and fit angle bracket between axle mounts
fit front wheel to bracket
check front wheel turns freely in air
set brake
Attach rope spaced ladder to wheel
staying on the upwind side of your surfaces
lay arch lines and handles across wind leave loose
keeping clear of lines
attach doused ss ring sets bottom tether to spaced ladder top ring
Lay the rings spaced and individually doused at 90-45 deg off the wind depending on strength
walk 90-60 deg downwind with lifter and set doused and pegged
connect the arch line/s ends to the last fit "ss cells" arch line
peg anchor the lift line beside the rings top bearing and connect
check lines again
check area again...
check how well bike is pegged
return to lifter with run down pulley
part inflate gradually to be confident of direction and force
slowly release choke by lowering a safe grip down the bridles
test that lifter is hand held with comfort otherwise choke then fold the lifter
shrink available lift surface area by detaching outermost side ss not actually tube cell sections with their bridle line (unzipping C curve cells)
reattach arch lines to new extremity "ss cells"
arch lines attach as per normal arch control style for your specific lifter
reattempt to step launch the lift
launch and walk down the lift line to the top ring
holding top ring edge detach pulley and stow
fill first ring
walk to subsequent rings fill and release along ladder to wheel
release brake and make a cup of tea

 right
whats next


Rod Read

Windswept and Interesting Limited
15a Aiginis
Isle of Lewis
HS2 0PB

07899057227
01851 870878