Is Sikorsky Attempting to Inhibit Others from Developing Electric Rotorcraft?
, perhaps if they concentrated on the jobs in hand !!
, perhaps if they concentrated on the jobs in hand !!
Join Date: Jun 2009
Location: Ct Upon Housatonic
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
Dave,
Interesting news.
It appears that the claimed invention is novel, as in never been done before, but obvious in view of the US Examiner's view of what is known in the art. As you pointed out, there had been consdierable work done in the field prior to Sikorsky's filing.
They have three months from November 19th within which to respond without extension fees, six months with extension fees, so we'll have a better understanding of their intent by May 19th.
They've got at least three options at this point. First, they could a abandon the application and move on to other things. Second, they could amend the claims, file a Request for Continued Examination, and pay for another examination of the application with a narrower set of claims. They would, however, be limited to the subject matter that was disclosed in the original specification. The original application was thin, so options are limited. Finally, they could appeal the Examiner's rejection and start down the judicial review route of the twice rejected claims.
Internationally, it's unclear what plans the have for protection in other countries. I don't see any foreign counterparts - and I specifically looked for a counterpart filing with the European Patent Office to cover Eurocopter and AW. However, in the event they did file with the EPO, I would expect to see the Europeans hammer them on inventiveness (similiar, but different from the US obviousness standard) based on the application's treatement by the US Examiner.
It's great to see the technical community engaged in the prosecution of an application as demonstrated here.
Cheers
- NonSAC
Interesting news.
It appears that the claimed invention is novel, as in never been done before, but obvious in view of the US Examiner's view of what is known in the art. As you pointed out, there had been consdierable work done in the field prior to Sikorsky's filing.
They have three months from November 19th within which to respond without extension fees, six months with extension fees, so we'll have a better understanding of their intent by May 19th.
They've got at least three options at this point. First, they could a abandon the application and move on to other things. Second, they could amend the claims, file a Request for Continued Examination, and pay for another examination of the application with a narrower set of claims. They would, however, be limited to the subject matter that was disclosed in the original specification. The original application was thin, so options are limited. Finally, they could appeal the Examiner's rejection and start down the judicial review route of the twice rejected claims.
Internationally, it's unclear what plans the have for protection in other countries. I don't see any foreign counterparts - and I specifically looked for a counterpart filing with the European Patent Office to cover Eurocopter and AW. However, in the event they did file with the EPO, I would expect to see the Europeans hammer them on inventiveness (similiar, but different from the US obviousness standard) based on the application's treatement by the US Examiner.
It's great to see the technical community engaged in the prosecution of an application as demonstrated here.
Cheers
- NonSAC
Thread Starter
Join Date: Apr 2003
Location: Vancouver, BC, Canada
Posts: 1,635
Likes: 0
Received 0 Likes
on
0 Posts
Hi NonSAC,
You mean that when the US Patent Office puts "THIS ACTION IS MADE FINIAL", in uppercase and bold, it ain"t really final?
Seriously, thanks for explaining the current state of the application and the options that Sikorsky might take.
A thanks must also be given to PPRuNe-Rotorhead management who allowed the discussion of rotorcraft technical subjects, and specifically the directly related electric postings that preceded Sikorsky's application.
I agree with the examiner on the mater of prior art and obviousness.
The claimed invention and its components may have never been patented before, however they certainly have been built before. There must be numerous model builders who have made rotorcraft with the attributes of this application. In fact, one model builder was the primary inventor, Jayant Sirohi, who made an open presentation and then a Web publication of his micro-craft. This open presentation preceded the patent application by more than a year.
In addition, a billion people can look inside their computers and see a servo-controlled rotor with an embedded coaxial electric motor, which is referred to as a fan. Many billions more have seen pictures of coaxial electric producing, servo controlled rotor blades, which are referred to as wind turbines.
Perhaps Sikorsky could advance rotorcraft if it came up with something original.
Dave
You mean that when the US Patent Office puts "THIS ACTION IS MADE FINIAL", in uppercase and bold, it ain"t really final?
Seriously, thanks for explaining the current state of the application and the options that Sikorsky might take.
A thanks must also be given to PPRuNe-Rotorhead management who allowed the discussion of rotorcraft technical subjects, and specifically the directly related electric postings that preceded Sikorsky's application.
I agree with the examiner on the mater of prior art and obviousness.
The claimed invention and its components may have never been patented before, however they certainly have been built before. There must be numerous model builders who have made rotorcraft with the attributes of this application. In fact, one model builder was the primary inventor, Jayant Sirohi, who made an open presentation and then a Web publication of his micro-craft. This open presentation preceded the patent application by more than a year.
In addition, a billion people can look inside their computers and see a servo-controlled rotor with an embedded coaxial electric motor, which is referred to as a fan. Many billions more have seen pictures of coaxial electric producing, servo controlled rotor blades, which are referred to as wind turbines.
Perhaps Sikorsky could advance rotorcraft if it came up with something original.
Dave
Last edited by Dave_Jackson; 19th Dec 2010 at 21:41.
Thread Starter
Join Date: Apr 2003
Location: Vancouver, BC, Canada
Posts: 1,635
Likes: 0
Received 0 Likes
on
0 Posts
NonSAC,
Sikorsky's lawyer sent a 'REQUEST FOR RECONSIDERATION' to the US Patent Office a few days ago.
It would appear that they are attempting to argue all 23 claims. Is this the judicial review route that you mentioned in your previous posting?
Dave
Sikorsky's lawyer sent a 'REQUEST FOR RECONSIDERATION' to the US Patent Office a few days ago.
It would appear that they are attempting to argue all 23 claims. Is this the judicial review route that you mentioned in your previous posting?
Dave
Join Date: Sep 2007
Location: USA
Posts: 601
Likes: 0
Received 0 Likes
on
0 Posts
Dave,
I have to agree that Sikorsky's application claims don't pass the "obvious to one skilled in the arts" standard. But it does pay to keep arguing the examiner's cause for rejecting claims as long as you can.
I submitted a patent application with 22 claims about 4 years ago. At first, all 22 claims were rejected by the examiner. After reading the reasons for rejection, it seemed apparent that what the examiner wrote was mostly cut-and-paste boilerplate. And most of the references cited were incorrect or misinterpreted. Frankly, it seemed as though the examiner was in a hurry writing his rejections and hoping that they would not be carefully checked. I checked every reference cited carefully and prepared detailed responses. After it was all over, the patent office allowed 20 of the 22 claims.
The fact that the original examiner was not careful and thorough reviewing my patent and issuing his findings kind of made me mad. Preparing and filing the responses to correct his sloppy work cost me time and money.
I have to agree that Sikorsky's application claims don't pass the "obvious to one skilled in the arts" standard. But it does pay to keep arguing the examiner's cause for rejecting claims as long as you can.
I submitted a patent application with 22 claims about 4 years ago. At first, all 22 claims were rejected by the examiner. After reading the reasons for rejection, it seemed apparent that what the examiner wrote was mostly cut-and-paste boilerplate. And most of the references cited were incorrect or misinterpreted. Frankly, it seemed as though the examiner was in a hurry writing his rejections and hoping that they would not be carefully checked. I checked every reference cited carefully and prepared detailed responses. After it was all over, the patent office allowed 20 of the 22 claims.
The fact that the original examiner was not careful and thorough reviewing my patent and issuing his findings kind of made me mad. Preparing and filing the responses to correct his sloppy work cost me time and money.
Thread Starter
Join Date: Apr 2003
Location: Vancouver, BC, Canada
Posts: 1,635
Likes: 0
Received 0 Likes
on
0 Posts
riff raff,
Thanks for mentioning your similar experience. Was the examiner's rejection of claims, which you challenged, the initial 'Non-Final Rejection' or the latter 'Final Rejection'?
I have not looked deeply into the examiner's rejection of Sikorsky's claims, nor do I know the nuances of 'Claims'. However, a cursory review suggests that the references he cited to previous patents may also be partially incorrect or misinterpreted.
What appears interesting about Sikorsky's application is that the examiner preceded the specific claim rejections with the following text.
Sikorsky is contesting the references to previous patents, however, they are not addressing the fact that all their claims were openly available and in the public domain. My 3rd-party submission, alone, covered 10 examples of previous public disclosures on the claims, which Sikorsky is attempting to usurp.
This is a excerpt from the US Manual of Patent Examining Procedure.
Dave
Thanks for mentioning your similar experience. Was the examiner's rejection of claims, which you challenged, the initial 'Non-Final Rejection' or the latter 'Final Rejection'?
I have not looked deeply into the examiner's rejection of Sikorsky's claims, nor do I know the nuances of 'Claims'. However, a cursory review suggests that the references he cited to previous patents may also be partially incorrect or misinterpreted.
What appears interesting about Sikorsky's application is that the examiner preceded the specific claim rejections with the following text.
Sikorsky is contesting the references to previous patents, however, they are not addressing the fact that all their claims were openly available and in the public domain. My 3rd-party submission, alone, covered 10 examples of previous public disclosures on the claims, which Sikorsky is attempting to usurp.
This is a excerpt from the US Manual of Patent Examining Procedure.
Dave
Join Date: Jun 2009
Location: Ct Upon Housatonic
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
Response After Final Office Action
Dave,
No, this is not the beginning of a judicial appeal of the Examiner's rejection. It may, however, be a lookahead of what Sikorsky's appeal brief might include.
Generally, once a final rejection has issued, an applicant has 6-months to either (1) pay for another examination and file a request for continuation, or (2) appeal the rejection to the Board of Patent Appeals and Interferences. If the applicant does neither, the application goes abandoned.
That said, an applicant may also file a response/amendment after a final office action prior to the six month period tolling. However, the proposed changes may only be minimal, and are entered only at the discretion of the examiner. The applicant no longer has the right to make amendments to the application.
Here, Sikorsky's Attorney elected to enter argument for allowability of the rejected claims and to not amend the claims further. It's a bit of Mexican standoff in that sense, and there may be a telephone discussion between the Attorney and Examiner to see if they can agree on any patentable subject matter. I have not read the references, so I can't make any statement regarding stength and weaknesses of the Attorney argument.
Proceduraly, one of two things will happen next. First, should the Examiner conclude that the argument is not persuasive, the Examiner will issue an Advisory Action explaining the reasoning for not allowing the application. Alternatively, in the event the Examiner finds this latest argument persuasive, the Examiner will issue a Notice of Allowance. And if there is a telephone call between the Examiner and Attorney of substance, an Interview Summary will put in the file.
Once one of an Advisory Action or Notice of Allowance hits the file the ball will be back in Sikorsky's court to file an RCE, appeal, or allow the application to go abandoned. The filing of a Notice of Appeal would indicate a choice to go the judicial appeal route to which I previously referred.
Cheers!
No, this is not the beginning of a judicial appeal of the Examiner's rejection. It may, however, be a lookahead of what Sikorsky's appeal brief might include.
Generally, once a final rejection has issued, an applicant has 6-months to either (1) pay for another examination and file a request for continuation, or (2) appeal the rejection to the Board of Patent Appeals and Interferences. If the applicant does neither, the application goes abandoned.
That said, an applicant may also file a response/amendment after a final office action prior to the six month period tolling. However, the proposed changes may only be minimal, and are entered only at the discretion of the examiner. The applicant no longer has the right to make amendments to the application.
Here, Sikorsky's Attorney elected to enter argument for allowability of the rejected claims and to not amend the claims further. It's a bit of Mexican standoff in that sense, and there may be a telephone discussion between the Attorney and Examiner to see if they can agree on any patentable subject matter. I have not read the references, so I can't make any statement regarding stength and weaknesses of the Attorney argument.
Proceduraly, one of two things will happen next. First, should the Examiner conclude that the argument is not persuasive, the Examiner will issue an Advisory Action explaining the reasoning for not allowing the application. Alternatively, in the event the Examiner finds this latest argument persuasive, the Examiner will issue a Notice of Allowance. And if there is a telephone call between the Examiner and Attorney of substance, an Interview Summary will put in the file.
Once one of an Advisory Action or Notice of Allowance hits the file the ball will be back in Sikorsky's court to file an RCE, appeal, or allow the application to go abandoned. The filing of a Notice of Appeal would indicate a choice to go the judicial appeal route to which I previously referred.
Cheers!
Join Date: Jun 2009
Location: Ct Upon Housatonic
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
Riff Raff,
I understand frustration at the process.
It's not uncommon that, upon review of the application, office action, and cited references, that an inventor/attorney gets frustrated with the examiner. In fairness however, when one considers the amount of time allocated by the PTO to the examiner to review the application, search the art, review the relevant art, and disposition the application, it at times precludes an examiner from generating a rejection that an engineer would describe as thorough. Right, wrong, or indifferent it's the nature of the beast.
And it's one reason why it is in the applicant's best interest to pursue similar claims in other countries. If only because a second set of eyes is a good thing, it makes sense. It also has the potential benefits of the search looking more closely at other art databases, testing the claims against different legal standards, and greater geographic coverage.
That said, prosecution is like a calibration. The applicant should present a continuum of rights, extending from a relatively broad, independent claim to comparatively narrow, set of dependent claims. The Examiner then surveys the art, and picks the place on the continuum where inventive activity begins and where rights therefor start. In Sikorsky's application the Examiner finds no such point on the presented continuum, either in the original set of claims, or withinthe narrower, amended set of claims.
In the example to which you make reference, such negotiation may explain difference between the claims ultimately issued in comparison to those orginally filed. It may take some time to review the application image file wrapper, but it should be discernable.
Regardless, I do agree that the process can be frustrating to an inventor. Particularly if the attorney fails to explain the process to the inventor when corresponding with an inventor to request assistance in reviewing cited art.
Cheers!
I understand frustration at the process.
It's not uncommon that, upon review of the application, office action, and cited references, that an inventor/attorney gets frustrated with the examiner. In fairness however, when one considers the amount of time allocated by the PTO to the examiner to review the application, search the art, review the relevant art, and disposition the application, it at times precludes an examiner from generating a rejection that an engineer would describe as thorough. Right, wrong, or indifferent it's the nature of the beast.
And it's one reason why it is in the applicant's best interest to pursue similar claims in other countries. If only because a second set of eyes is a good thing, it makes sense. It also has the potential benefits of the search looking more closely at other art databases, testing the claims against different legal standards, and greater geographic coverage.
That said, prosecution is like a calibration. The applicant should present a continuum of rights, extending from a relatively broad, independent claim to comparatively narrow, set of dependent claims. The Examiner then surveys the art, and picks the place on the continuum where inventive activity begins and where rights therefor start. In Sikorsky's application the Examiner finds no such point on the presented continuum, either in the original set of claims, or withinthe narrower, amended set of claims.
In the example to which you make reference, such negotiation may explain difference between the claims ultimately issued in comparison to those orginally filed. It may take some time to review the application image file wrapper, but it should be discernable.
Regardless, I do agree that the process can be frustrating to an inventor. Particularly if the attorney fails to explain the process to the inventor when corresponding with an inventor to request assistance in reviewing cited art.
Cheers!
Join Date: Jun 2009
Location: Ct Upon Housatonic
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
Dave,
With respect to the grounds for rejection under 35 USC 103, this is the obviousness statute. And in the mechanical arts, it is relatively unsettled. The trend is for the PTO to be more strict today that prior to a 2007 due to judicial decision that caused the PTO to make it harder to allow applications in view of this statute.
Of note in connection with our original discussion on this application is the second sentence of the statute. Judicially, the phrase 'not negatived by the manner in which it was made' has been interpreted in dispensing with what was at one time known as the "flash of creative genius" test/requirement/standard. As such, it provides some explanation as to why disclosures that one of skill in the art like yourself might consider to be thin ultimately yield rights to at least a portion of the disclosure.
With respect to the Examiner choosing to not cite to your submission, you could call the Examiner and pose the question directly. The Examiner may tell you that he cannot provide an explanation, but he might also explain his reasoning to you. But understand that his only binding obligation was to consider the submission, and reflect such in the application image file wrapper.
- Cheers!
With respect to the grounds for rejection under 35 USC 103, this is the obviousness statute. And in the mechanical arts, it is relatively unsettled. The trend is for the PTO to be more strict today that prior to a 2007 due to judicial decision that caused the PTO to make it harder to allow applications in view of this statute.
Of note in connection with our original discussion on this application is the second sentence of the statute. Judicially, the phrase 'not negatived by the manner in which it was made' has been interpreted in dispensing with what was at one time known as the "flash of creative genius" test/requirement/standard. As such, it provides some explanation as to why disclosures that one of skill in the art like yourself might consider to be thin ultimately yield rights to at least a portion of the disclosure.
With respect to the Examiner choosing to not cite to your submission, you could call the Examiner and pose the question directly. The Examiner may tell you that he cannot provide an explanation, but he might also explain his reasoning to you. But understand that his only binding obligation was to consider the submission, and reflect such in the application image file wrapper.
- Cheers!
Last edited by NonSAC; 30th Jan 2011 at 13:33.
Thread Starter
Join Date: Apr 2003
Location: Vancouver, BC, Canada
Posts: 1,635
Likes: 0
Received 0 Likes
on
0 Posts
NonSAC,
As previously, and previously, and previously ..........
, thank you.
Since Sikorsky's lawyer and the Examiner are passing their telephone numbers back and forth, I will take your suggestion and phone the Examiner.
___________________
Overview:
The likelihood is that electric propulsion will follow the same path that was taken by the internal combustion engine and the turbine. This path was one of moving through the levels of vehicle efficiency/payload ratio, until reaching the helicopter. So far, Sikorsky has only shown the static placement of an electric motor in the hole that was previously filled by a reciprocating engine [the Firefly]. This method has actually been flown in the past, albeit most or all were without onboard batteries.
In addition, this direct substitution of motor for engine is not the most effective configuration. The most effective configuration is to have the motor inline with the propeller/rotor. This inline configuration has been realized in thousands of ships, submarines, and airplanes, etc. Initial by the use of engines and later by the use of motors. This coaxial relationship of motor and propeller already exists in unmanned and manned airplanes.
IMHO, it would be a shame if one company was able to claim ownership to this blatantly obvious method of electrically driving a helicopter. And then, 'lockup' the rights to the future production and sales of efficient electric rotorcraft in the United States.
Dave
As previously, and previously, and previously ..........
, thank you.Since Sikorsky's lawyer and the Examiner are passing their telephone numbers back and forth, I will take your suggestion and phone the Examiner.
___________________
Overview:
The likelihood is that electric propulsion will follow the same path that was taken by the internal combustion engine and the turbine. This path was one of moving through the levels of vehicle efficiency/payload ratio, until reaching the helicopter. So far, Sikorsky has only shown the static placement of an electric motor in the hole that was previously filled by a reciprocating engine [the Firefly]. This method has actually been flown in the past, albeit most or all were without onboard batteries.
In addition, this direct substitution of motor for engine is not the most effective configuration. The most effective configuration is to have the motor inline with the propeller/rotor. This inline configuration has been realized in thousands of ships, submarines, and airplanes, etc. Initial by the use of engines and later by the use of motors. This coaxial relationship of motor and propeller already exists in unmanned and manned airplanes.
IMHO, it would be a shame if one company was able to claim ownership to this blatantly obvious method of electrically driving a helicopter. And then, 'lockup' the rights to the future production and sales of efficient electric rotorcraft in the United States.
Dave
Last edited by Dave_Jackson; 8th Feb 2011 at 01:01. Reason: Removed the last paragraph. Then corrected the spelling of NonSAC's name
Thread Starter
Join Date: Apr 2003
Location: Vancouver, BC, Canada
Posts: 1,635
Likes: 0
Received 0 Likes
on
0 Posts
riff raff,
You will likely find the following Bloomberg Businessweek article very interesting.
It expands on NonSAC's comments to you, and on the action that is taking place with the Sikorsky Patent Application.
Are Patent Problems Stifling U.S. Innovation?
Dave
You will likely find the following Bloomberg Businessweek article very interesting.
It expands on NonSAC's comments to you, and on the action that is taking place with the Sikorsky Patent Application.
Are Patent Problems Stifling U.S. Innovation?
Dave
Thread Starter
Join Date: Apr 2003
Location: Vancouver, BC, Canada
Posts: 1,635
Likes: 0
Received 0 Likes
on
0 Posts
On Friday the Patent Office responded to Sikorsky's lawyer. It informs the lawyer that "reply filed 20 January 2011 fails to place this application in condition for allowance".
This USPTO response concludes by saying "Lastly, it is clear that the Applicant did not take into account the cited NPL prior art cited by a third party on 7/17/2009, as these references, as well as the combination of prior art discussed disclose the applicants invention."
__________________________
Sikorsky's #1 claim is: "A rotary-wing aircraft comprising: a rotor system rotatable about an axis of rotation; and an electric motor mounted along said axis of rotation to drive said rotor system about said axis of rotation."
75 years of electric motors and helicopter rotors rotating about a common axis?
A picture from Steve Coates book 'Helicopters of the Third Reich'.
An article in the April 1938 issue of Flight, which has a similar picture.
If anyone can e-mail me with a means of obtaining additional information on Focke's test craft, or any other relevant information, IMHO it will eventually be appreciated by the rotorcraft industry.
Dave
This USPTO response concludes by saying "Lastly, it is clear that the Applicant did not take into account the cited NPL prior art cited by a third party on 7/17/2009, as these references, as well as the combination of prior art discussed disclose the applicants invention."
__________________________
Sikorsky's #1 claim is: "A rotary-wing aircraft comprising: a rotor system rotatable about an axis of rotation; and an electric motor mounted along said axis of rotation to drive said rotor system about said axis of rotation."
75 years of electric motors and helicopter rotors rotating about a common axis?
A picture from Steve Coates book 'Helicopters of the Third Reich'.
An article in the April 1938 issue of Flight, which has a similar picture.
If anyone can e-mail me with a means of obtaining additional information on Focke's test craft, or any other relevant information, IMHO it will eventually be appreciated by the rotorcraft industry.
Dave
Thread Starter
Join Date: Apr 2003
Location: Vancouver, BC, Canada
Posts: 1,635
Likes: 0
Received 0 Likes
on
0 Posts
Today the US Patent Office sent their response from 'The Board of Patent Appeals and Interferences' to Sikorsky's lawyer.
All 23 claims have been rejected!
Also, no 'period for reply' was given, which possibly implies that any further action on the part of Sikorsky will have to take place in a Court.
Dave
All 23 claims have been rejected!
Also, no 'period for reply' was given, which possibly implies that any further action on the part of Sikorsky will have to take place in a Court.
Dave
Join Date: Jun 2009
Location: Ct Upon Housatonic
Posts: 31
Likes: 0
Received 0 Likes
on
0 Posts
Dave,
It is interesting to see the Examiner's comment regarding the NPL in the advisory action as it's not my understanding that the Applicant is under any obligation wahtsoever to discuss, much less argue over, art not cited in a rejection.
It will be interesting to see if Sikorsky takes the rejection to the Board of Patent Appeals and Interferences. That Sikorsky allowed the European counterpart to the US application, EP08861121.5, to be 'deemed withdrawn' by not paying the third annuity suggests that they will not.
Cheers!
It is interesting to see the Examiner's comment regarding the NPL in the advisory action as it's not my understanding that the Applicant is under any obligation wahtsoever to discuss, much less argue over, art not cited in a rejection.
It will be interesting to see if Sikorsky takes the rejection to the Board of Patent Appeals and Interferences. That Sikorsky allowed the European counterpart to the US application, EP08861121.5, to be 'deemed withdrawn' by not paying the third annuity suggests that they will not.
Cheers!
Thread Starter
Join Date: Apr 2003
Location: Vancouver, BC, Canada
Posts: 1,635
Likes: 0
Received 0 Likes
on
0 Posts
NonSAC,
Shoot! Are you politely saying that the document 'BEFORE THE BOARD OF PATENT APPEALS AND INTERFERENCES' is TO the board not FROM the board?
____________________________________
Thank you for the considerable procedural assistance that you provide. The Third Party Submission would have been difficult, if not impossible, without your coaching.
I took your earlier advice and telephoned the examiner. Subsequently, two days before the Notice of Appeal was received, the following links were e-mailed to him. They are in addition to the Third Party Submission of Non-Patent Literature.
The so-called 'new ideas' in Sikorsky's patent application;
As always, thank's.
Dave
Shoot! Are you politely saying that the document 'BEFORE THE BOARD OF PATENT APPEALS AND INTERFERENCES' is TO the board not FROM the board?
____________________________________
Thank you for the considerable procedural assistance that you provide. The Third Party Submission would have been difficult, if not impossible, without your coaching.
I took your earlier advice and telephoned the examiner. Subsequently, two days before the Notice of Appeal was received, the following links were e-mailed to him. They are in addition to the Third Party Submission of Non-Patent Literature.
The so-called 'new ideas' in Sikorsky's patent application;
- were used in the wind tunnel testing of the worlds first successful helicopter and published in An article in the April 1938 issue of Flight. Then, published again in Steve Coates 2003 book 'Helicopters of the Third Reich'.
- were published in NASA's 1981 public report; Practical Feasibility Assessment of Electric Power Propulsion in Small Helicopters using Lithium Hydroxide Battery Technology.
As always, thank's.
Dave
Last edited by Dave_Jackson; 23rd Jun 2011 at 05:39.
