Citation Design
Join Date: Aug 2011
Location: Grassy Valley
Posts: 2,074
Likes: 0
Received 0 Likes
on
0 Posts
From John tullamarine:
The applicant (ie the organisation applying for the STC) needs to show compliance with the Design Standards so the effort lies with the applicant rather than the regulator. The regulator's task is to ensure such compliance to minimise the risk of dodgy things getting into the mainstream .. experimental category is for doing one's own thing.
Who develops the design standards? For instance, having been through the Patent process, I found, surprisingly, it is not necessary for the patented device to function....it is only required that it be different from prior patented devices!
If found of no value, ( by anyone, or FAA) could the regulator prevent its installation?
The applicant (ie the organisation applying for the STC) needs to show compliance with the Design Standards so the effort lies with the applicant rather than the regulator. The regulator's task is to ensure such compliance to minimise the risk of dodgy things getting into the mainstream .. experimental category is for doing one's own thing.
Who develops the design standards? For instance, having been through the Patent process, I found, surprisingly, it is not necessary for the patented device to function....it is only required that it be different from prior patented devices!
If found of no value, ( by anyone, or FAA) could the regulator prevent its installation?
Moderator
When we talk about Design Standards, we are referring to documents such as FAR 23, FAR 25, etc. These are developed by the Regulator in accordance with obligations pursuant to ICAO decisions. In general, a particular Design Standard will comply with ICAO requirements other than in respect of differences notified formally by the relevant State.
I have never seen any interest on the part of aviation Regulators when discussion gets around to patents. The latter are a civil matter for litigation and design protection and, as such, are not within the ambit of the Regulator.
The Regulator will (should) act to ensure that the requirements of the Design Standards are met. If, for instance, a proposed gadget doesn't work then, so long as it doesn't create a problem, there is no reason why the applicant can't waste its money and effort on incorporating it. Problem belong applicant, not Regulator.
Sometimes, a Type may be found to have a problem some time after Certification and the TC basis may be reviewed. On occasion, additional or changed requirements may be imposed to fix such an after the event problem.
I have never seen any interest on the part of aviation Regulators when discussion gets around to patents. The latter are a civil matter for litigation and design protection and, as such, are not within the ambit of the Regulator.
The Regulator will (should) act to ensure that the requirements of the Design Standards are met. If, for instance, a proposed gadget doesn't work then, so long as it doesn't create a problem, there is no reason why the applicant can't waste its money and effort on incorporating it. Problem belong applicant, not Regulator.
Sometimes, a Type may be found to have a problem some time after Certification and the TC basis may be reviewed. On occasion, additional or changed requirements may be imposed to fix such an after the event problem.
Join Date: May 2003
Posts: 409
Likes: 0
Received 0 Likes
on
0 Posts
Actuator,
The attached picture is of a flange that has been added to portions of the trailing edge of the rudder and the electrical rudder tab on a Lear 45. As I said before, I was told this was done as a service bulleting to allow flight without the yaw damper.
Is this similar to what you see on the Citation?
Hawk
You can see the rudder tab at the bottom, with the rudder pretty well filling out the rest of the picture. The under portion of the right horizontal stab is on the right.
The attached picture is of a flange that has been added to portions of the trailing edge of the rudder and the electrical rudder tab on a Lear 45. As I said before, I was told this was done as a service bulleting to allow flight without the yaw damper.
Is this similar to what you see on the Citation?
Hawk
You can see the rudder tab at the bottom, with the rudder pretty well filling out the rest of the picture. The under portion of the right horizontal stab is on the right.
Last edited by hawk37; 29th May 2012 at 21:57.
Join Date: Mar 2011
Location: engineer at large
Posts: 1,409
Likes: 0
Received 0 Likes
on
0 Posts
Lyman,
A Patent has nothing to do with application, permitting, or certification.
Figure this, a paint scheme on the aircraft requires certification. There are also many parts of the aircraft in the common domain, of which there is no patent, that require a cert.
While a thicken edge may work on that specific variant of that specific aircraft, it may not work on a variant of that same aircraft, and certainly not on any other aircraft.
Winglets would be a great example to follow.
A Patent has nothing to do with application, permitting, or certification.
Figure this, a paint scheme on the aircraft requires certification. There are also many parts of the aircraft in the common domain, of which there is no patent, that require a cert.
While a thicken edge may work on that specific variant of that specific aircraft, it may not work on a variant of that same aircraft, and certainly not on any other aircraft.
Winglets would be a great example to follow.
Join Date: Aug 2011
Location: Grassy Valley
Posts: 2,074
Likes: 0
Received 0 Likes
on
0 Posts
Forgive the denseness, I'm trying to suss the similarities twixt USPATOFF and STC. The Attorney gets 335/hour, and you sound every bit as smart, so my question is: does there exist a proprietary interest in what can be described as the "value" of developing an STC.
Winglets are both trademarked and Patented, afaik, so how do they compare with a "Paint Scheme", which sounds more like a badging thing, or Trademark issue than STC, or Patent?
The work on the Lear looks, erm, kind of "homey". Non countersunk screws, and deformation of what looks like aluminum, uncovered. (Probably SS).
What is its purpose? Sorry, it replaces the Yaw Damper? I can see why that may not be subject to Patent, or STC. So of course it is approved, is there an STC, to read?
Winglets are both trademarked and Patented, afaik, so how do they compare with a "Paint Scheme", which sounds more like a badging thing, or Trademark issue than STC, or Patent?
The work on the Lear looks, erm, kind of "homey". Non countersunk screws, and deformation of what looks like aluminum, uncovered. (Probably SS).
What is its purpose? Sorry, it replaces the Yaw Damper? I can see why that may not be subject to Patent, or STC. So of course it is approved, is there an STC, to read?
Last edited by Lyman; 29th May 2012 at 23:16.
Join Date: Dec 2010
Location: Middle America
Age: 84
Posts: 1,167
Likes: 0
Received 0 Likes
on
0 Posts
Lyman,
Perhaps a review of what the STC process is and how it is granted, or not, would be helpful. Don't confuse it with a patent application or patent issuance, they are two different subjects. An STC may often be not patentable but useful for installation on an aircraft. Conversely, a patented item or idea, although deemed valid, may not be determined useful enough to warrant installation. It is as simple as that, don't try to merge or confuse the two...
From the FAA:
TD
Perhaps a review of what the STC process is and how it is granted, or not, would be helpful. Don't confuse it with a patent application or patent issuance, they are two different subjects. An STC may often be not patentable but useful for installation on an aircraft. Conversely, a patented item or idea, although deemed valid, may not be determined useful enough to warrant installation. It is as simple as that, don't try to merge or confuse the two...
From the FAA:
STC process - major steps, as required
Applicant applies for STC
Familiarization and preliminary type certification board (TCB) meetings
FAA develops certification program plan
Establishment of certification basis by FAA
Applicant submits data for approval
FAA design evaluation
FAA and applicant hold specialists and interim type certification meetings, as required
FAA performs conformity inspections
Engineering compliance determinations
Pre-flight TCB Meeting
Applicant performs ground inspections, ground tests, and flight tests
FAA reviews manufacturer's flight test results and issues TIA
FAA performs conformity inspections, witnesses tests, performs official certification flight tests and flight standards evaluations
Functional and reliability testing
FAA approves flight manual supplement or supplemental flight manual and holds final TCB meeting
AEG completes continuing airworthiness determination
FAA issues STC
An STC will be issued only if:
the pertinent technical data have been examined and found satisfactory,
all necessary tests and compliance inspections have been completed, and
the alteration has been found to conform with the technical data.&
An STC will not be issued to:
approve minor changes, or for approval of identical replacement parts, unless the installation of such parts constitutes a major change to the type design
approve design changes to Technical Standard Order (TSO) approved articles unless the TSO is invalidated for the modified article. An STC which modifies a TSO article must provide for installation
combine two or more STCs without additional showing of compliance; or
manufacturers or applicants outside of the U.S., except as provided for in a bilateral agreement.
Applicant applies for STC
Familiarization and preliminary type certification board (TCB) meetings
FAA develops certification program plan
Establishment of certification basis by FAA
Applicant submits data for approval
FAA design evaluation
FAA and applicant hold specialists and interim type certification meetings, as required
FAA performs conformity inspections
Engineering compliance determinations
Pre-flight TCB Meeting
Applicant performs ground inspections, ground tests, and flight tests
FAA reviews manufacturer's flight test results and issues TIA
FAA performs conformity inspections, witnesses tests, performs official certification flight tests and flight standards evaluations
Functional and reliability testing
FAA approves flight manual supplement or supplemental flight manual and holds final TCB meeting
AEG completes continuing airworthiness determination
FAA issues STC
An STC will be issued only if:
the pertinent technical data have been examined and found satisfactory,
all necessary tests and compliance inspections have been completed, and
the alteration has been found to conform with the technical data.&
An STC will not be issued to:
approve minor changes, or for approval of identical replacement parts, unless the installation of such parts constitutes a major change to the type design
approve design changes to Technical Standard Order (TSO) approved articles unless the TSO is invalidated for the modified article. An STC which modifies a TSO article must provide for installation
combine two or more STCs without additional showing of compliance; or
manufacturers or applicants outside of the U.S., except as provided for in a bilateral agreement.
Join Date: Mar 2011
Location: engineer at large
Posts: 1,409
Likes: 0
Received 0 Likes
on
0 Posts
Lyman,
I have several patents, and have been through the process and application. In the aviation world, you have to look at the history of aviation to understand just how many patents may be out there.
The paint scheme is a trademark, but each scheme or configuration needs to go through cert, simply due to weights on the paint. Sorry, but in the grand scheme of things, when the FAA certs are down to tens of pounds, the paint on a 747 can weigh a lot!
I have several patents, and have been through the process and application. In the aviation world, you have to look at the history of aviation to understand just how many patents may be out there.
The paint scheme is a trademark, but each scheme or configuration needs to go through cert, simply due to weights on the paint. Sorry, but in the grand scheme of things, when the FAA certs are down to tens of pounds, the paint on a 747 can weigh a lot!
Thread Starter
Join Date: Jun 2000
Location: Johannesburg, South Africa
Posts: 80
Likes: 0
Received 0 Likes
on
0 Posts
Thanks Hawk, my interweb prowess does not extend to posting a photo (yet). That is similar, the Citation does not have it on the tab though just the lower portion of the rudder and without the riviets behind. It extends about 1/4 cm 90 degrees to the rudder surface on both sides.
Join Date: Sep 2002
Location: Pfffft
Posts: 218
Likes: 0
Received 0 Likes
on
0 Posts
Lyman: I think I see what you're trying to get at with your questioning.
When an organisation applies for, and is granted, an STC by the FAA/EASA/etc, they effectively 'own' that modification. If anyone else would like to perform the same installation under the cover of that STC, they would need to be given the relevant design/installation/cert data by the initial organisation.
So, is there an inherent value to undertaking an STC? Yes, there is, if it's something that other aircraft owners want.
A good working example would be the recent regulatory changes which require 8.33 kHz spaced communication radios. Let's say I designed a modification for the 737 Classic to replace the existing radios with compliant radios under an STC. I could reasonably expect to be able to 'sell' the use of this STC to other 737 Classic owners, under which they could upgrade their radios.
An STC isn't exclusively a mechanism for protecting intellectual property, but it does permit you to own a particular modification which you can then sell to others.
When an organisation applies for, and is granted, an STC by the FAA/EASA/etc, they effectively 'own' that modification. If anyone else would like to perform the same installation under the cover of that STC, they would need to be given the relevant design/installation/cert data by the initial organisation.
So, is there an inherent value to undertaking an STC? Yes, there is, if it's something that other aircraft owners want.
A good working example would be the recent regulatory changes which require 8.33 kHz spaced communication radios. Let's say I designed a modification for the 737 Classic to replace the existing radios with compliant radios under an STC. I could reasonably expect to be able to 'sell' the use of this STC to other 737 Classic owners, under which they could upgrade their radios.
An STC isn't exclusively a mechanism for protecting intellectual property, but it does permit you to own a particular modification which you can then sell to others.
Last edited by Another St Ivian; 30th May 2012 at 11:35.
Join Date: Aug 2011
Location: Grassy Valley
Posts: 2,074
Likes: 0
Received 0 Likes
on
0 Posts
the Patent process
Awesome, that is exactly what I wanted. My desire springs from a way to make money on a system I have developed, and the Patent Process is bizarre. I spent ten thousand dollars (unavoidable) to gain information that was useless. I should have directed it at development of the system, and networking with users.
Thank you, I am in your debt.
Actuator. That sounds like the T strip. But it also sounds like a stiffener at the corner of the Rudder, an area that takes great abuse at times. If, instead of driving the airstream, the corner is driven by jet blast, the stress is quite high, and in an unplanned for region, given its lightweight and the stop it has against a stronger structure, (the VStab).
The .25cm entry into the airstream would be interesting to compare, as percentage of chord, with the data John Tullamarine supplied. It sounds miniscule, but a week ago, I didn't know what a Tstrip was. Gotta love this place....
Thank you, I am in your debt.
Actuator. That sounds like the T strip. But it also sounds like a stiffener at the corner of the Rudder, an area that takes great abuse at times. If, instead of driving the airstream, the corner is driven by jet blast, the stress is quite high, and in an unplanned for region, given its lightweight and the stop it has against a stronger structure, (the VStab).
The .25cm entry into the airstream would be interesting to compare, as percentage of chord, with the data John Tullamarine supplied. It sounds miniscule, but a week ago, I didn't know what a Tstrip was. Gotta love this place....
Last edited by Lyman; 30th May 2012 at 16:37.
Join Date: Dec 2010
Location: Middle America
Age: 84
Posts: 1,167
Likes: 0
Received 0 Likes
on
0 Posts
Lyman,
Another St Ivian is correct in what he says about STCs. But, an important fact is not addressed, that being liability. Take the case of modifying an aircraft with a devise that was not included as part of the original Type Certification by means of an STC. As holder and owner of the STC, you now assume liability for that devise, should it, for whatever reason, fail resulting in damage to the aircraft, personal injury or loss of life. The original aircraft manufacturer is absolved. In other words, STCs come with responsibilities in addition to ownership and or profit making opportunity. Just so you know...
TD
Another St Ivian is correct in what he says about STCs. But, an important fact is not addressed, that being liability. Take the case of modifying an aircraft with a devise that was not included as part of the original Type Certification by means of an STC. As holder and owner of the STC, you now assume liability for that devise, should it, for whatever reason, fail resulting in damage to the aircraft, personal injury or loss of life. The original aircraft manufacturer is absolved. In other words, STCs come with responsibilities in addition to ownership and or profit making opportunity. Just so you know...
TD
Join Date: Aug 2011
Location: Grassy Valley
Posts: 2,074
Likes: 0
Received 0 Likes
on
0 Posts
I am aware... If a new development passes the regulator, and its process, negligence is negligible, that leaves man defect or improper install.
My favorite pair of words: By Others. That and good insurance, presto a new sailboat....
One cannot get within twenty feet of the chocks w/o gaining exposure to suit.
That actually is not a bad thing, the more John Does, the more dilute the finding, and the less the award...
As in Engineering, in LAW it is always best to spread the stress...
Wanna lose your tail rotor?
My favorite pair of words: By Others. That and good insurance, presto a new sailboat....
One cannot get within twenty feet of the chocks w/o gaining exposure to suit.
That actually is not a bad thing, the more John Does, the more dilute the finding, and the less the award...
As in Engineering, in LAW it is always best to spread the stress...
Wanna lose your tail rotor?
Last edited by Lyman; 30th May 2012 at 20:50.
Join Date: Sep 2002
Location: Pfffft
Posts: 218
Likes: 0
Received 0 Likes
on
0 Posts
Actually, that's where the whole affair becomes rather unpalatable as a business proposition.
Just because your modification passes the regulatory hurdles and gains approval, it doesn't mean the certifying authority is at any time underwriting your work. It's entirely possible that a civil lawsuit further down the line could find you guilty of negligence despite having received approval for your mod.
This sort of thing is exactly what killed many GA manufacturers in the last few decades. If you're interested, have a google around for some of the lawsuits held against Cessna, Lycoming et al.
Just because your modification passes the regulatory hurdles and gains approval, it doesn't mean the certifying authority is at any time underwriting your work. It's entirely possible that a civil lawsuit further down the line could find you guilty of negligence despite having received approval for your mod.
This sort of thing is exactly what killed many GA manufacturers in the last few decades. If you're interested, have a google around for some of the lawsuits held against Cessna, Lycoming et al.
Join Date: Aug 2011
Location: Grassy Valley
Posts: 2,074
Likes: 0
Received 0 Likes
on
0 Posts
I think a lot of innovative and important work is shelved, waiting for tort reform.
My best hope is to sell the system to a manufacturer, or, less probable, licensure. And the money is not huge. It's there, but the process is discouraging at times. Lawyers.... They're not people.
My best hope is to sell the system to a manufacturer, or, less probable, licensure. And the money is not huge. It's there, but the process is discouraging at times. Lawyers.... They're not people.
Join Date: Mar 2011
Location: engineer at large
Posts: 1,409
Likes: 0
Received 0 Likes
on
0 Posts
The Patent process itself, can be rather inexpensive for a private person.
The trick is to get the Patent in the door, with a provisional patent.
This allows you to market the device, to perhaps an OEM manufacturer, while being protected by the provisional patent.
That way, you can sell the patent, and let them finalize the process, or begin to license the patent, and pay the rest with those monies.
In reality, anything associated in aviation is a liability. Even though your innovation may not have been the cause, it will still be encumbered in the legal process, and you may be potentially dragged in.
That is why many of the patents are sold off to patent houses such as Intellectual Ventures.
Good luck.
The trick is to get the Patent in the door, with a provisional patent.
This allows you to market the device, to perhaps an OEM manufacturer, while being protected by the provisional patent.
That way, you can sell the patent, and let them finalize the process, or begin to license the patent, and pay the rest with those monies.
In reality, anything associated in aviation is a liability. Even though your innovation may not have been the cause, it will still be encumbered in the legal process, and you may be potentially dragged in.
That is why many of the patents are sold off to patent houses such as Intellectual Ventures.
Good luck.
Join Date: Aug 2011
Location: Grassy Valley
Posts: 2,074
Likes: 0
Received 0 Likes
on
0 Posts
Thank you for all your help, and another st ivian and TD. The most reward I have already, I have the prototype, and it is protected. As you must know, the key design is patience
Moderator
I have no legal competence but I suggest that an STC provides negligible protection against having the design ideas pinched by others.
Protection is the province of patents, registered designs, and the like.
Protection is the province of patents, registered designs, and the like.
Join Date: Aug 2011
Location: Grassy Valley
Posts: 2,074
Likes: 0
Received 0 Likes
on
0 Posts
Concurrent pathways would be advisable. The patent would seem to be a priority, as the difficult and expensive part, the implementation, could be borne by others. Gurney was sol because it wasn't his idea in the first place.
Prior Art...
Prior Art...
Join Date: May 2003
Posts: 409
Likes: 0
Received 0 Likes
on
0 Posts
Actuator,
SB 45-55-6 for the lear 45 will "install straps of the trailing edge" of the rudder and rudder trim tab assembly. The "reason" was that "Learjet has received reports of yaw fluctuations (dutch roll) during flight. Accomplishment of this SB will reduce the dutch roll tendency of the aircraft during flight"
From the AFM; "aircraft not modified must have yaw damper engaged for all flight operations except take off and landing. On modified aircraft the yaw damper use is not required"
so the mod somehow negates the requirement for the use of the yaw damper.
Perhaps Cessna did the same?
Hawk
SB 45-55-6 for the lear 45 will "install straps of the trailing edge" of the rudder and rudder trim tab assembly. The "reason" was that "Learjet has received reports of yaw fluctuations (dutch roll) during flight. Accomplishment of this SB will reduce the dutch roll tendency of the aircraft during flight"
From the AFM; "aircraft not modified must have yaw damper engaged for all flight operations except take off and landing. On modified aircraft the yaw damper use is not required"
so the mod somehow negates the requirement for the use of the yaw damper.
Perhaps Cessna did the same?
Hawk
Join Date: Aug 2011
Location: Grassy Valley
Posts: 2,074
Likes: 0
Received 0 Likes
on
0 Posts
Perhaps a variation of aileron spades, which in null, provide very little drag, but power steering with input....
Strikes me it is a mechanical yaw damper, providing Rudder input from null, due added asym drag til returned to neutral... pretty slick. And from slop, w/o control input.
Strikes me it is a mechanical yaw damper, providing Rudder input from null, due added asym drag til returned to neutral... pretty slick. And from slop, w/o control input.
