---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 06/27/10: 15 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:04 AM - Re: Audio system design (Radioflyer) 2. 11:05 AM - Re: Re: Audio system design (Daniel Hooper) 3. 11:36 AM - Re: Re: Push Button "Speed Brakes"? (Valin & Allyson Thorn) 4. 11:38 AM - Re: Re: Push Button "Speed Brakes"? (Robert L. Nuckolls, III) 5. 02:32 PM - Re: Re: Push Button "Speed Brakes"? (Robert Sultzbach) 6. 02:34 PM - Re: Re: Push Button "Speed Brakes"? (Bob McCallum) 7. 03:34 PM - Toggle Relay (Gordon Smith) 8. 03:34 PM - LV Warn Light vs. Alternator Light (Gordon Smith) 9. 04:26 PM - Re: LV Warn Light vs. Alternator Light (Robert L. Nuckolls, III) 10. 04:26 PM - Re: Re: Push Button "Speed Brakes"? (Valin & Allyson Thorn) 11. 04:26 PM - Re: Re: Push Button "Speed Brakes"? (Valin & Allyson Thorn) 12. 06:28 PM - Starter light (Loman) 13. 07:11 PM - Re: Re: Push Button "Speed Brakes"? (Bob McCallum) 14. 07:18 PM - Re: Starter light (Robert L. Nuckolls, III) 15. 07:39 PM - Re: Toggle Relay (Bob McCallum) ________________________________ Message 1 _____________________________________ Time: 04:04:24 AM PST US Subject: AeroElectric-List: Re: Audio system design From: "Radioflyer" Someone asked where to get the unit I suggested. The CS-408 unit is from Precision Instrument & Control, Inc. (Ft Worth, TX). The company sells these directly. They are an electronics OEM for several aircraft manufacturers. I'm away from my files so can't provide the phone number, but they are probably listed in the phonebooks. Harvey is the main contact there for this product. Between the CS-408, the VX unit, and the Aerolectric unit, there is no longer any excuse for not having an almost invisible "audio panel". --Jose Read this topic online here: http://forums.matronics.com/viewtopic.php?p=302661#302661 ________________________________ Message 2 _____________________________________ Time: 11:05:21 AM PST US Subject: Re: AeroElectric-List: Re: Audio system design From: Daniel Hooper Is this it? http://maps.google.com/places/us/tx/haslet/aviator-dr/512/-precision-instrument-&-control?hl=en&gl=us --Daniel On Jun 27, 2010, at 6:03 AM, Radioflyer wrote: > > Someone asked where to get the unit I suggested. The CS-408 unit is from Precision Instrument & Control, Inc. (Ft Worth, TX). The company sells these directly. They are an electronics OEM for several aircraft manufacturers. I'm away from my files so can't provide the phone number, but they are probably listed in the phonebooks. Harvey is the main contact there for this product. Between the CS-408, the VX unit, and the Aerolectric unit, there is no longer any excuse for not having an almost invisible "audio panel". > --Jose > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=302661#302661 > > > > > > > > > > ________________________________ Message 3 _____________________________________ Time: 11:36:29 AM PST US From: "Valin & Allyson Thorn" Subject: RE: AeroElectric-List: Re: Push Button "Speed Brakes"? Hi Bob and everyone, Thanks for the history of the Precise Flight Speedbrakes/Spoilers. Since they brand them "speed brakes" I've been using that term even though I know they are really spoilers. The accident scenario you described really brings to light how someone without a clear understanding of what they actually do could call for them at a bad time. I think they can be easily misunderstood since even spoilers can perform as speed brakes. I like to think of them as lift/drag ratio reducers. As you point out, an aircraft designer can go after bumping up the drag side or lowering the lift side to give the pilot more aircraft control when high on energy and wanting less altitude and/or airspeed. Even as spoilers they can act like speed brakes since when deployed, lowering lift, one can increase the wing angle of attack to keep the same lift (hold same altitude rate) while getting higher drag at the new higher AOA, slowing the airplane down. Anyway, your accident example has convinced me to label them as spoilers and not speed brakes. The discussion has me reconsidering my decision to add the spoiler control to the joystick grips. But, let me summarize my rules for picking what's on the stick. 1. Actions required frequently 2. Functions needed while it's very inconvenient to remove hand from throttle 3. No functions that if accidentally activated would create a safety of flight issue So these are my basic criteria for selecting what's switches are on the joystick. Based on this, I've tentatively made these assignments: THORN Legacy Joystick Button Assignments.jpg For those who can't see the graphic, I have: Hat Switch: Pitch & Yaw Trim Trigger: Radio Transmit Lower Button: Alarm Mute Upper Right Button: Autopilot On/Off Toggle Upper Left Button: Spoilers Up/Down Toggle I did not put flaps or gear on the stick since one usually only activates them twice during a typical cross country flight and if they were to be accidentally deployed when flying too fast it would damage the aircraft - violating strategy rule 3 above. I'm thinking having the spoilers on the stick is a good option because the Lancair Legacy is a very low drag airframe making them very useful for descents, the Legacy can be easily landed with them deployed, and there is no speed limit on their deployment. With this discussion ongoing I have heard from a Legacy flyer with a spoiler switch on his throttle control and that he wishes he had a guard on it because it has been accidentally activated a few times. The good news from his experiences is that he'd even landed without realizing they were deployed and it was not an issue. I'm also checking with another Legacy flyer who has the control on his joystick to see if it's been a problem for him or if he'd do it again. From earlier discussion with him he said he did it because the Mooney he used to fly had it that way and it was very convenient to toggle them when needed on descents. Anyway, I appreciate and encourage the discussion about the best way to design all this with aircraft operations and human factors in mind. Even if I don't do it this way, I'd still like to know the best way to design a circuit to toggle back and forth between two poles with a push button switch. J Anyone have any advice on that question? Thanks, Valin -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Saturday, June 26, 2010 11:45 PM Subject: AeroElectric-List: Re: Push Button "Speed Brakes"? At 08:24 PM 6/26/2010, you wrote: >I think it has to have a voltage applied at pin 7 continuously to >keep the speed brakes up. It's designed so that if the unit loses >power they fail to the retracted position. This is an excellent topic for discussions of failure mode effects analysis =AND= understand the simple-ideas behind the system design goals. A really important side note concerning the Precise Flight product is that it's not a "speed brake" in the aerodynamic sense of the phrase . . . A speed brake is a means by which aerodynamic DRAG is added to the mix of thrust-lift-mass-drag combination that dictates airframe behavior/performance. Drag can be and most often is added to the performance mix by throwing large surface areas out into the slipstream. I've participated in programs that crafted special actuators to extend large panels out of aft locations on the airplane where design goals called for an increase in the airframe's total drag component while having little or no effect on lift. Large air transport aircraft will lift rather large areas of aluminum from the top surface of the wing. In cruising flight, only the outboard panels will occasionally lift during roll control maneuvers. In this mode, the panels are SPOILERS that reduce lift on one wing at a time. Loss of lift augments rolling moment offered by the ailerons. However, during landing roll-out, one often sees every square foot of aluminum through out into the breeze with the obvious intent of making the whole machine a very draggy aerodynamic shape where flying efficiency is not important while slowing down is most important. The space shuttle has a bifurcated rudder that can be simultaneously extend both to the right and left of the vertical fin for the purpose of throwing out some aerodynamic drag. The Precise Flight product is the brainchild of on Bill Thompson who was chief of flight test at Cessna single engine division while I was a tech writer. Bill was directly responsible for introducing me to Ken Razak, former dean of engineering at Wichita State who became my second most revered mentor, business partner and friend with more than 40 years of collaboration on interesting things. But that's another story. Bill's product first evolved on the Cessna 210 and was later approved for installation on a host of TC aircraft. I was introduced to the device in Kerrville, TX by a Mooney test pilot and later on another Mooney by George Masey. It was then that I was given to understand that the Precise flight product is NOT A SPEED BRAKE. It's a SPOILER. Design goals for this device call for reducing lift on the wing while having very little effect on total drag. The artfully installed blades can be extended during a stabilized approach to offer a profound effect on rate of descent while having little effect on pitch angle or indicated airspeed. There are similar devices on the top of the wing in a Beechjet that offer augmentation of tiny ailerons for roll control in fight -OR- an increased rate of descent when fully extended on both sides. These also are NOT SPEED BRAKES. They might be extended during a roll out for the purpose of killing lift to increase weight on wheels and improve braking by the tires . . . but their effect as aerodynamic speed brakes is nil. The reason why this distinction is important has to do with proper and useful deployment of SPOILERS. I'm working an accident case where a pilot reports having extended his Precise Flight "speed brakes" a few seconds before an off-airport landing. He was under the mistaken understanding that they would help slow things down before an un-planned contact with the ground. In fact, the impact forces were probably GREATER than if he had not extended the SPOILERS at all. The net effect of extending the Precise Flight paddles on top of the wing was to INCREASE rate of descent to the ground. So after understanding what these things are designed to do for you, I'll suggest that its a really good thing to make sure that under no circumstances can they can extend when you don't want them to and that they can always be retracted when they're not needed . . . or their extension would increase risks of bent airplanes or broken people. When considering departures from the manufacture's instructions, make sure that you're not crafting a situation that increases risk of unintended extension or loss of pilot control for that extension. The system should probably include an easily accessed power switch. Removal of power from the system insures positive retraction irrespective of what other switch becomes stuck. Itty-bitty switches on stick-grips are not renowned for their robustness. Take care that your quest for convenience does not increase risks for un-intended consequences. Bob . . . ________________________________ Message 4 _____________________________________ Time: 11:38:59 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Push Button "Speed Brakes"? At 11:44 PM 6/26/2010, you wrote: > My late-night contribution to this thread was hammered out too quickly and after the 3rd straight, 14-hour day working one of Dr. Dee's "mother of all garage sales". The organization, syntax and typos in the posting left much to be desired. Here's an updated version of the posting which is in much better shape. http://www.aeroelectric.com/articles/Speed_Brakes_vs_Spoilers.pdf As always, comments and corrections welcome. Bob . . . ________________________________ Message 5 _____________________________________ Time: 02:32:50 PM PST US From: Robert Sultzbach Subject: Re: AeroElectric-List: Re: Push Button "Speed Brakes"? Hi Valin,=0A=0A I would suggest putting them on the throttle. That is whe re they were on military aircraft I flew. The beauty of having them there is it is extremely easy to develop a habit pattern of activating the spoile rs to retract WHENEVER you ask for full power. There are thumb switches th at have existed for these production aircraft so I would think they would b e available. See if you can find pictures of military aircraft like the A- 4 whose throttle had that setup. As the throttle is advanced the thumb pus hes the thumb switch forward to retract the spoilers and vice versa when lo w thrust high drag is needed. Good luck.=0A=0A=0A =0A=0ASent from my iPhon e=0A=0AOn Jun 28, 2010, at 2:34, "Valin & Allyson Thorn" wrote:=0A=0AHi Bob and everyone,=0A=0A =0A=0AThanks for the history o f the Precise Flight Speedbrakes/Spoilers. Since they brand them =9C speed brakes=9D I=99ve been using that term even though I know they are really spoilers. The accident scenario you described really bring s to light how someone without a clear understanding of what they actually do could call for them at a bad time. =0A=0A =0A=0AI think they can be easi ly misunderstood since even spoilers can perform as speed brakes. I like t o think of them as lift/drag ratio reducers. As you point out, an aircraft designer can go after bumping up the drag side or lowering the lift side t o give the pilot more aircraft control when high on energy and wanting less altitude and/or airspeed. Even as spoilers they can act like speed brakes since when deployed, lowering lift, one can increase the wing angle of att ack to keep the same lift (hold same altitude rate) while getting higher dr ag at the new higher AOA, slowing the airplane down=0A=0A =0A=0AAn yway, your accident example has convinced me to label them as spoilers and not speed brakes.=0A=0A =0A=0AThe discussion has me reconsidering my decisi on to add the spoiler control to the joystick grips. But, let me summarize my rules for picking what=99s on the stick.=0A=0A =0A=0A1. Ac tions required frequently=0A=0A2. Functions needed while it=99s very inconvenient to remove hand from throttle=0A=0A3. No functions that if accidentally activated would create a safety of flight issue=0A=0A =0A=0ASo these are my basic criteria for selecting what=99s switches are on the joystick. Based on this, I=99ve tentatively made these as signments:=0A=0A =0A=0A=0A=0AFor those who can=99t see the graphic, I have:=0A=0A =0A=0AHat Switch: Pitch & Yaw Trim=0A=0ATrigger : Radio Transmit=0A=0ALower Button: Alarm Mute=0A=0AUpper Right Button: Au topilot On/Off Toggle=0A=0AUpper Left Button: Spoilers Up/Down Toggle=0A=0A =0A=0AI did not put flaps or gear on the stick since one usually only acti vates them twice during a typical cross country flight and if they were to be accidentally deployed when flying too fast it would damage the aircraft =93 violating strategy rule 3 above.=0A=0A =0A=0AI=99m thinking having the spoilers on the stick is a good option because the Lancair Lega cy is a very low drag airframe making them very useful for descents, the Le gacy can be easily landed with them deployed, and there is no speed limit o n their deployment. With this discussion ongoing I have heard from a Legac y flyer with a spoiler switch on his throttle control and that he wishes he had a guard on it because it has been accidentally activated a few times. The good news from his experiences is that he=99d even landed withou t realizing they were deployed and it was not an issue. I=99m also c hecking with another Legacy flyer who has the control on his joystick to se e if it=99s been a problem for him or if he=99d do it again. F rom earlier discussion with him he said he did it because the Mooney he use d to fly had it that way and it was very convenient to toggle them when nee ded on descents.=0A=0A =0A=0AAnyway, I appreciate and encourage the discuss ion about the best way to design all this with aircraft operations and huma n factors in mind. =0A=0A =0A=0AEven if I don=99t do it this way, I =99d still like to know the best way to design a circuit to toggle ba ck and forth between two poles with a push button switch J Anyone have any advice on that question?=0A=0A =0A=0AThanks,=0A=0A =0A=0AValin=0A =0A =0A=0A =0A=0A =0A=0A =0A=0A-----Original Message-----=0AFrom: owner-aer oelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@ matronics.com] On Behalf Of Robert L. Nuckolls, III=0ASent: Saturday, June 26, 2010 11:45 PM=0ATo: aeroelectric-list@matronics.com=0ASubject: AeroElec tric-List: Re: Push Button "Speed Brakes"?=0A=0A =0A=0A--> AeroElectric-Lis t message posted by: "Robert L. Nuckolls, III" =0A=0A =0A=0AAt 08:24 PM 6/26/2010, you wrote:=0A=0A>I think it has to h ave a voltage applied at pin 7 continuously to=0A=0A>keep the speed brakes up. It's designed so that if the unit loses=0A=0A>power they fail to the r etracted position.=0A=0A =0A=0A =0A=0A This is an excellent topic for dis cussions of failure=0A=0A mode effects analysis =AND= understand the simple-ideas=0A=0A behind the system design goals.=0A=0A =0A=0A A reall y important side note concerning the Precise Flight=0A=0A product is that it's not a "speed brake" in the aerodynamic=0A=0A sense of the phrase . . .=0A=0A =0A=0A A speed brake is a means by which aerodynamic DRAG is=0A =0A added to the mix of thrust-lift-mass-drag combination=0A=0A that di ctates airframe behavior/performance. Drag can=0A=0A be and most often is added to the performance mix by=0A=0A throwing large surface areas out i nto the slipstream.=0A=0A =0A=0A I've participated in programs that craft ed special=0A=0A actuators to extend large panels out of aft=0A=0A loca tions on the airplane where design goals called for=0A=0A an increase in the airframe's total drag component=0A=0A while having little or no effe ct on lift.=0A=0A =0A=0A Large air transport aircraft will lift rather la rge=0A=0A areas of aluminum from the top surface of the wing.=0A=0A In cruising flight, only the outboard panels will=0A=0A occasionally lift du ring roll control maneuvers. In=0A=0A this mode, the panels are SPOILERS that reduce lift=0A=0A on one wing at a time. Loss of lift augments rolli ng=0A=0A moment offered by the ailerons.=0A=0A =0A=0A However, during l anding roll-out, one often sees=0A=0A every square foot of aluminum throu gh out into=0A=0A the breeze with the obvious intent of making the=0A=0A whole machine a very draggy aerodynamic shape where=0A=0A flying effici ency is not important while slowing=0A=0A down is most important.=0A=0A =0A=0A The space shuttle has a bifurcated rudder that can=0A=0A be simu ltaneously extend both to the right and left=0A=0A of the vertical fin fo r the purpose of throwing out=0A=0A some aerodynamic drag.=0A=0A =0A=0A The Precise Flight product is the brainchild of on=0A=0A Bill Thompson w ho was chief of flight test at Cessna=0A=0A single engine division while I was a tech writer.=0A=0A Bill was directly responsible for introducing me to=0A=0A Ken Razak, former dean of engineering at Wichita=0A=0A Stat e who became my second most revered mentor,=0A=0A business partner and fr iend with more than 40 years=0A=0A of collaboration on interesting things . But that's=0A=0A another story.=0A=0A =0A=0A Bill's product first evo lved on the Cessna 210=0A=0A and was later approved for installation on a host=0A=0A of TC aircraft. I was introduced to the device=0A=0A in Ker rville, TX by a Mooney test pilot and later=0A=0A on another Mooney by Ge orge Masey.=0A=0A =0A=0A It was then that I was given to understand that =0A=0A the Precise flight product is NOT A SPEED BRAKE.=0A=0A It's a SP OILER. Design goals for this device call=0A=0A for reducing lift on the w ing while having very=0A=0A little effect on total drag. The artfully ins talled=0A=0A blades can be extended during a stabilized approach=0A=0A to offer a profound effect on rate of descent=0A=0A while having little e ffect on pitch angle or=0A=0A indicated airspeed.=0A=0A =0A=0A There ar e similar devices on the top of the wing=0A=0A in a Beechjet that offer a ugmentation of tiny=0A=0A ailerons for roll control in fight -OR- an incr eased=0A=0A rate of descent when fully extended on both sides.=0A=0A Th ese also are NOT SPEED BRAKES. They might be extended=0A=0A during a roll out for the purpose of killing lift=0A=0A to increase weight on wheels a nd improve braking=0A=0A by the tires . . . but their effect as aerodynam ic=0A=0A speed brakes is nil.=0A=0A =0A=0A The reason why this distinct ion is important has=0A=0A to do with proper and useful deployment of SPO ILERS.=0A=0A I'm working an accident case where a pilot reports=0A=0A h aving extended his Precise Flight "speed brakes"=0A=0A a few seconds befo re an off-airport landing. He=0A=0A was under the mistaken understanding that they=0A=0A would help slow things down before an un-planned=0A=0A contact with the ground. In fact, the impact forces=0A=0A were probably G REATER than if he had not extended=0A=0A the SPOILERS at all. The net eff ect of extending the=0A=0A Precise Flight paddles on top of the wing was to=0A=0A INCREASE rate of descent to the ground.=0A=0A =0A=0A So after understanding what these things are designed=0A=0A to do for you, I'll su ggest that its a really good=0A=0A thing to make sure that under no circu mstances=0A=0A can they can extend when you don't want them to=0A=0A an d that they can always be retracted when they're=0A=0A not needed . . . o r their extension would increase=0A=0A risks of bent airplanes or broken people.=0A=0A =0A=0A When considering departures from the manufacture's =0A=0A instructions, make sure that you're not crafting=0A=0A a situati on that increases risk of unintended=0A=0A extension or loss of pilot con trol for that=0A=0A extension. The system should probably include an=0A =0A easily accessed power switch. Removal of power=0A=0A from the syste m insures positive retraction=0A=0A irrespective of what other switch bec omes=0A=0A stuck.=0A=0A =0A=0A Itty-bitty switches on stick-grips are n ot renowned=0A=0A for their robustness. Take care that your quest=0A=0A for convenience does not increase risks for=0A=0A un-intended consequenc es.=0A=0A =0A=0A Bob . . .=0A=0A =0A=0A =0A=0A=0Ato browse=0AUn/Subscript ion,=0ABrowse, Chat, FAQ,=0Amore:=0Ahttp://www.matronics.com/Navigator?Aero Electric-List=0A=0AWeb Forums!=0Ahttp://forums.matronics.com=0A=0Asupport! =0A=0Ahttp://www.matronics.com/contribution=0A =0A=0A =0A=0A =0A=0A=0A=0A ________________________________ Message 6 _____________________________________ Time: 02:34:49 PM PST US From: "Bob McCallum" Subject: RE: AeroElectric-List: Re: Push Button "Speed Brakes"? Valin; The simplest circuit to accomplish your request would be to use your SPST push button to switch coil power to a bi-stable relay and use the relay contacts to switch the power to whatever load you wish. Each push of the button will toggle the relay. The second item on this page (part number RLY7742) is an example of a 12VDC 15 amp DPDT bi-stable relay. http://tinyurl.com/2ffvkur Bob McC _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Valin & Allyson Thorn Sent: Sunday, June 27, 2010 2:35 PM Subject: RE: AeroElectric-List: Re: Push Button "Speed Brakes"? Hi Bob and everyone, Thanks for the history of the Precise Flight Speedbrakes/Spoilers. Since they brand them "speed brakes" I've been using that term even though I know they are really spoilers. The accident scenario you described really brings to light how someone without a clear understanding of what they actually do could call for them at a bad time. ****** Big Clip********** Anyway, I appreciate and encourage the discussion about the best way to design all this with aircraft operations and human factors in mind. Even if I don't do it this way, I'd still like to know the best way to design a circuit to toggle back and forth between two poles with a push button switch. :-) Anyone have any advice on that question? Thanks, Valin ________________________________ Message 7 _____________________________________ Time: 03:34:53 PM PST US From: Gordon Smith Subject: AeroElectric-List: Toggle Relay Is there a 12V. Relay device (SPST or SPDT) that can be toggled OFF/ON from a remote momentary SPST mini switch?- It should remain in the off or on position until toggled again. -I am looking for something in the class of a S704-1 regarding robustness and capacity. - Gordon Smith ________________________________ Message 8 _____________________________________ Time: 03:34:54 PM PST US From: Gordon Smith Subject: AeroElectric-List: LV Warn Light vs. Alternator Light Given =93 You have installed a device for active notification of low voltage that moniters Main Bus voltage and lights an indicator lamp/Led if voltage drops below a programmed level. =C2- The first thought if this light comes on is that the alternator is off line and not outputting to the battery or aircraft bus systems. =C2-However t his is not necessarily true. =C2- Can not there be a condition where the alternator is puitting out it =99s maximum capacity but you are trying to use a total load greater than t hat capacity. =C2-I think this would eventually pull the battery and main bus voltage down to a point where the LV warning light would turn on. =C2- My thought was that maybe it would be advantageous to have an additional in dicator of alternator function.=C2- Many regulators for both field wound and/or permanent magnet alternators have a =9Clight=9D. =C2-B ut what does that light actually tell you? =C2- On a schematic supplied by Jabiru for the J3300 the stock supplied regulato r for the permanent magnet regulator system has a =9Clight=9D c onnection. =C2-It is identified as =9CTo Low Voltage Warning Light =9D.=C2- Is this just redundant LV warning or does it actually tell =C2- if the there is alternator output? =C2- Gordon Smith ________________________________ Message 9 _____________________________________ Time: 04:26:52 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: LV Warn Light vs. Alternator Light > >The first thought if this light comes on is that >the alternator is off line and not outputting to >the battery or aircraft bus systems. However this is not necessarily true. > >Can not there be a condition where the >alternator is puitting out its maximum >capacity but you are trying to use a total load >greater than that capacity. I think this would >eventually pull the battery and main bus voltage >down to a point where the LV warning light would turn on. Not if one has accomplished the customary load analysis. The legacy approach to sizing alternators to loads makes it impossible to overload the alternator. Now, if one PLANS to have more potential load than the alternator can carry, then an alternator loadmeter is indicated to assist the pilot in turning things on/off as needed to stay within the alternator's capabilities. >My thought was that maybe it would be >advantageous to have an additional indicator of >alternator function. Many regulators for both >field wound and/or permanent magnet alternators >have a light. But what does that light actually tell you? Those are in the same class as the alternator warning light on vehicles for 50+ years. They accurately indicate a broken wire, broken belt and some system failures but not all. An they're not a LV warning light. The stand-alone, active notification of LV is still the single most useful electrical system flight instrument. >On a schematic supplied by Jabiru for the J3300 >the stock supplied regulator for the permanent >magnet regulator system has a light >connection. It is identified as To Low >Voltage Warning Light. Is this just >redundant LV warning or does it actually >tell if the there is alternator output? Same as cited above. Not a 'real' lv warning system. Bob . . . ________________________________ Message 10 ____________________________________ Time: 04:26:52 PM PST US From: "Valin & Allyson Thorn" Subject: RE: AeroElectric-List: Re: Push Button "Speed Brakes"? Thanks Robert -- that would be nice if I didn=99t already have a throttle quadrant that isn=99t very conducive to adding a switch to it See photo below. Valin throttle quadrant 2009.jpg From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert Sultzbach Sent: Sunday, June 27, 2010 4:31 PM Subject: Re: AeroElectric-List: Re: Push Button "Speed Brakes"? Hi Valin, I would suggest putting them on the throttle. That is where they were on military aircraft I flew. The beauty of having them there is it is extremely easy to develop a habit pattern of activating the spoilers to retract WHENEVER you ask for full power. There are thumb switches that have existed for these production aircraft so I would think they would be available. See if you can find pictures of military aircraft like the A-4 whose throttle had that setup. As the throttle is advanced the thumb pushes the thumb switch forward to retract the spoilers and vice versa when low thrust high drag is needed. Good luck. Sent from my iPhone On Jun 28, 2010, at 2:34, "Valin & Allyson Thorn" wrote: Hi Bob and everyone, Thanks for the history of the Precise Flight Speedbrakes/Spoilers. Since they brand them =9Cspeed brakes=9D I=99ve been using that term even though I know they are really spoilers. The accident scenario you described really brings to light how someone without a clear understanding of what they actually do could call for them at a bad time. I think they can be easily misunderstood since even spoilers can perform as speed brakes. I like to think of them as lift/drag ratio reducers. As you point out, an aircraft designer can go after bumping up the drag side or lowering the lift side to give the pilot more aircraft control when high on energy and wanting less altitude and/or airspeed. Even as spoilers they can act like speed brakes since when deployed, lowering lift, one can increase the wing angle of attack to keep the same lift (hold same altitude rate) while getting higher drag at the new higher AOA, slowing the airplane down Anyway, your accident example has convinced me to label them as spoilers and not speed brakes. The discussion has me reconsidering my decision to add the spoiler control to the joystick grips. But, let me summarize my rules for picking what=99s on the stick. 1. Actions required frequently 2. Functions needed while it=99s very inconvenient to remove hand from throttle 3. No functions that if accidentally activated would create a safety of flight issue So these are my basic criteria for selecting what=99s switches are on the joystick. Based on this, I=99ve tentatively made these assignments: For those who can=99t see the graphic, I have: Hat Switch: Pitch & Yaw Trim Trigger: Radio Transmit Lower Button: Alarm Mute Upper Right Button: Autopilot On/Off Toggle Upper Left Button: Spoilers Up/Down Toggle I did not put flaps or gear on the stick since one usually only activates them twice during a typical cross country flight and if they were to be accidentally deployed when flying too fast it would damage the aircraft =93 violating strategy rule 3 above. I=99m thinking having the spoilers on the stick is a good option because the Lancair Legacy is a very low drag airframe making them very useful for descents, the Legacy can be easily landed with them deployed, and there is no speed limit on their deployment. With this discussion ongoing I have heard from a Legacy flyer with a spoiler switch on his throttle control and that he wishes he had a guard on it because it has been accidentally activated a few times. The good news from his experiences is that he=99d even landed without realizing they were deployed and it was not an issue. I=99m also checking with another Legacy flyer who has the control on his joystick to see if it=99s been a problem for him or if he=99d do it again. >From earlier discussion with him he said he did it because the Mooney he used to fly had it that way and it was very convenient to toggle them when needed on descents. Anyway, I appreciate and encourage the discussion about the best way to design all this with aircraft operations and human factors in mind. Even if I don=99t do it this way, I=99d still like to know the best way to design a circuit to toggle back and forth between two poles with a push button switch J Anyone have any advice on that question? Thanks, Valin -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Saturday, June 26, 2010 11:45 PM Subject: AeroElectric-List: Re: Push Button "Speed Brakes"? At 08:24 PM 6/26/2010, you wrote: >I think it has to have a voltage applied at pin 7 continuously to >keep the speed brakes up. It's designed so that if the unit loses >power they fail to the retracted position. This is an excellent topic for discussions of failure mode effects analysis =AND= understand the simple-ideas behind the system design goals. A really important side note concerning the Precise Flight product is that it's not a "speed brake" in the aerodynamic sense of the phrase . . . A speed brake is a means by which aerodynamic DRAG is added to the mix of thrust-lift-mass-drag combination that dictates airframe behavior/performance. Drag can be and most often is added to the performance mix by throwing large surface areas out into the slipstream. I've participated in programs that crafted special actuators to extend large panels out of aft locations on the airplane where design goals called for an increase in the airframe's total drag component while having little or no effect on lift. Large air transport aircraft will lift rather large areas of aluminum from the top surface of the wing. In cruising flight, only the outboard panels will occasionally lift during roll control maneuvers. In this mode, the panels are SPOILERS that reduce lift on one wing at a time. Loss of lift augments rolling moment offered by the ailerons. However, during landing roll-out, one often sees every square foot of aluminum through out into the breeze with the obvious intent of making the whole machine a very draggy aerodynamic shape where flying efficiency is not important while slowing down is most important. The space shuttle has a bifurcated rudder that can be simultaneously extend both to the right and left of the vertical fin for the purpose of throwing out some aerodynamic drag. The Precise Flight product is the brainchild of on Bill Thompson who was chief of flight test at Cessna single engine division while I was a tech writer. Bill was directly responsible for introducing me to Ken Razak, former dean of engineering at Wichita State who became my second most revered mentor, business partner and friend with more than 40 years of collaboration on interesting things. But that's another story. Bill's product first evolved on the Cessna 210 and was later approved for installation on a host of TC aircraft. I was introduced to the device in Kerrville, TX by a Mooney test pilot and later on another Mooney by George Masey. It was then that I was given to understand that the Precise flight product is NOT A SPEED BRAKE. It's a SPOILER. Design goals for this device call for reducing lift on the wing while having very little effect on total drag. The artfully installed blades can be extended during a stabilized approach to offer a profound effect on rate of descent while having little effect on pitch angle or indicated airspeed. There are similar devices on the top of the wing in a Beechjet that offer augmentation of tiny ailerons for roll control in fight -OR- an increased rate of descent when fully extended on both sides. These also are NOT SPEED BRAKES. They might be extended during a roll out for the purpose of killing lift to increase weight on wheels and improve braking by the tires . . . but their effect as aerodynamic speed brakes is nil. The reason why this distinction is important has to do with proper and useful deployment of SPOILERS. I'm working an accident case where a pilot reports having extended his Precise Flight "speed brakes" a few seconds before an off-airport landing. He was under the mistaken understanding that they would help slow things down before an un-planned contact with the ground. In fact, the impact forces were probably GREATER than if he had not extended the SPOILERS at all. The net effect of extending the Precise Flight paddles on top of the wing was to INCREASE rate of descent to the ground. So after understanding what these things are designed to do for you, I'll suggest that its a really good thing to make sure that under no circumstances can they can extend when you don't want them to and that they can always be retracted when they're not needed . . . or their extension would increase risks of bent airplanes or broken people. When considering departures from the manufacture's instructions, make sure that you're not crafting a situation that increases risk of unintended extension or loss of pilot control for that extension. The system should probably include an easily accessed power switch. Removal of power from the system insures positive retraction irrespective of what other switch becomes stuck. Itty-bitty switches on stick-grips are not renowned for their robustness. Take care that your quest for convenience does not increase risks for un-intended consequences. Bob . . . to browse Un/Subscription, Browse, Chat, FAQ, more: http://www.matronics.com/Navigator?AeroElectric-List Web Forums! http://forums.matronics.com support! http://www.matronics.com/contribution ________________________________ Message 11 ____________________________________ Time: 04:26:52 PM PST US From: "Valin & Allyson Thorn" Subject: RE: AeroElectric-List: Re: Push Button "Speed Brakes"? Thanks Bob - looks like something along those lines would do the trick. These examples switch AC current with the DC control. I'm not sure if that matters or not. But, I figured relays that behave like this must be out there somewhere. Guess I need DPST bi-stable 24V DC relay. Valin From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Bob McCallum Sent: Sunday, June 27, 2010 4:34 PM Subject: RE: AeroElectric-List: Re: Push Button "Speed Brakes"? Valin; The simplest circuit to accomplish your request would be to use your SPST push button to switch coil power to a bi-stable relay and use the relay contacts to switch the power to whatever load you wish. Each push of the button will toggle the relay. The second item on this page (part number RLY7742) is an example of a 12VDC 15 amp DPDT bi-stable relay. http://tinyurl.com/2ffvkur Bob McC _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Valin & Allyson Thorn Sent: Sunday, June 27, 2010 2:35 PM Subject: RE: AeroElectric-List: Re: Push Button "Speed Brakes"? Hi Bob and everyone, Thanks for the history of the Precise Flight Speedbrakes/Spoilers. Since they brand them "speed brakes" I've been using that term even though I know they are really spoilers. The accident scenario you described really brings to light how someone without a clear understanding of what they actually do could call for them at a bad time. ****** Big Clip********** Anyway, I appreciate and encourage the discussion about the best way to design all this with aircraft operations and human factors in mind. Even if I don't do it this way, I'd still like to know the best way to design a circuit to toggle back and forth between two poles with a push button switch. J Anyone have any advice on that question? Thanks, Valin ________________________________ Message 12 ____________________________________ Time: 06:28:06 PM PST US Subject: AeroElectric-List: Starter light From: "Loman" Other builders tell me they wired in a light to indicate that the starter motor is 'doin its thang'. They value this because you can't hear a Lycoming starter working and if it continues running, due to welded contacts or some other problem in the circuit, something needs to be done about it. What I would really like is a light to indicate A) that the starter is available to be engaged OR B) is actually energized and working. It would switch off when the engine was running and the starter was no longer working. Such a light would come back on when the engine was cut off as long as the master is still on. This is pretty much how my car status lights work. I am still learning about electrics but would somebody more knowledgeable know; can a starter light be wired to this effect and how would it be done? I will be using the z13/8 architecture for my RV-9. -------- Loman O'Byrne RV-9 builder: Emp Done, Wings Done, Fuse underway Dublin, Ireland Read this topic online here: http://forums.matronics.com/viewtopic.php?p=302755#302755 ________________________________ Message 13 ____________________________________ Time: 07:11:10 PM PST US From: "Bob McCallum" Subject: RE: AeroElectric-List: Re: Push Button "Speed Brakes"? Valin; You're welcome. The 24V version would be part #RLY7443 4th item down on the link I sent previously. Also although they state these relays switch AC they work equally well on DC as the switching elements are mechanical micro switches. You can see this detail clearly if you view the photos on the linked page. Bob McC _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Valin & Allyson Thorn Sent: Sunday, June 27, 2010 7:21 PM Subject: RE: AeroElectric-List: Re: Push Button "Speed Brakes"? Thanks Bob - looks like something along those lines would do the trick. These examples switch AC current with the DC control. I'm not sure if that matters or not. But, I figured relays that behave like this must be out there somewhere. Guess I need DPST bi-stable 24V DC relay. Valin From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Bob McCallum Sent: Sunday, June 27, 2010 4:34 PM Subject: RE: AeroElectric-List: Re: Push Button "Speed Brakes"? Valin; The simplest circuit to accomplish your request would be to use your SPST push button to switch coil power to a bi-stable relay and use the relay contacts to switch the power to whatever load you wish. Each push of the button will toggle the relay. The second item on this page (part number RLY7742) is an example of a 12VDC 15 amp DPDT bi-stable relay. http://tinyurl.com/2ffvkur Bob McC _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Valin & Allyson Thorn Sent: Sunday, June 27, 2010 2:35 PM Subject: RE: AeroElectric-List: Re: Push Button "Speed Brakes"? Hi Bob and everyone, Thanks for the history of the Precise Flight Speedbrakes/Spoilers. Since they brand them "speed brakes" I've been using that term even though I know they are really spoilers. The accident scenario you described really brings to light how someone without a clear understanding of what they actually do could call for them at a bad time. ****** Big Clip********** Anyway, I appreciate and encourage the discussion about the best way to design all this with aircraft operations and human factors in mind. Even if I don't do it this way, I'd still like to know the best way to design a circuit to toggle back and forth between two poles with a push button switch. :-) Anyone have any advice on that question? Thanks, Valin ________________________________ Message 14 ____________________________________ Time: 07:18:58 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Starter light At 08:26 PM 6/27/2010, you wrote: Other builders tell me they wired in a light to indicate that the starter motor is 'doin its thang'. They value this because you can't hear a Lycoming starter working and if it continues running, due to welded contacts or some other problem in the circuit, something needs to be done about it. What I would really like is a light to indicate A) that the starter is available to be engaged OR B) is actually energized and working. It would switch off when the engine was running and the starter was no longer working. Such a light would come back on when the engine was cut off as long as the master is still on. This is pretty much how my car status lights work. I am still learning about electrics but would somebody more knowledgeable know; can a starter light be wired to this effect and how would it be done? I will be using the Z13/8 architecture for my RV-9. A simple "starter energized" light is powered from the downstream side of the starter contactor. It's illuminated all times the contactor is closed either because your finger is on the button . . . or because it's stuck. See: http://www.aeroelectric.com/Pictures/Schematics/Starter_Engaged_Warning_Lt.pdf Do an archives search on "starter engaged" for a constellation of the problem and variables associated with the various starter technologies. Bob . . . ________________________________ Message 15 ____________________________________ Time: 07:39:45 PM PST US From: "Bob McCallum" Subject: RE: AeroElectric-List: Toggle Relay Gordon; See my reply to Valin re: the speed brakes thread, a couple of posts up the list. This bi-stable relay does what you are describing. The one I cited is a DPDT device rated 15 amps per contact. You could parallel the two contacts to approximate the 704's rating. The contacts won't precisely share the load but unless you are running at absolutely max rating they'll work well. If the switch ratings are a real concern, the supplied switches on this relay could be replaced with Omron V-15-1C5 switches which are rated at 15Amps 250VDC. Bob McC _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Gordon Smith Sent: Sunday, June 27, 2010 6:33 PM Subject: AeroElectric-List: Toggle Relay Is there a 12V. Relay device (SPST or SPDT) that can be toggled OFF/ON from a remote momentary SPST mini switch? It should remain in the off or on position until toggled again. I am looking for something in the class of a S704-1 regarding robustness and capacity. Gordon Smith ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.