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Re: [europa-committee] RE: Europa-List: Re: Vertical Power VP-X Pro

Subject: Re: [europa-committee] RE: Europa-List: Re: Vertical Power VP-X Pro
From: Pete <peterz@zutrasoft.com>
Date: Sat, 10 Mar 2018 19:47:05
Edge performance now has a 32A crank alternator fwiw.

http://webshop.edgeperformance.no/index.php?id_product=458&controller=pr
oduct

> On Mar 10, 2018, at 6:20 PM, Bud Yerly <budyerly@msn.com> wrote:
> 
> From: Bud Yerly
> Sent: Saturday, March 10, 2018 2:59 PM
> To: Mike Gregory
> Subject: RE: [europa-committee] RE: Europa-List: Re: Vertical Power VP-X P
ro
>  
> Mike and all.
>  
> Here I go again, keep in mind I have a love hate relationship with every c
omponent in an aircraft.
>  
> One piece of advise, be an amp zealot!
> 40-60 amp alternators are necessary on some pieces of equipment.  Like a m
otor home, yacht, or like my neighbor kids car with incandescent lighting (h
e likes the warm glow I guess) power everything, and his wonderful stereo he
 shares with everyone around him.  Just kidding.
>  
> The Europa is a light simple aircraft.  Today our aircraft for IFR really p
ush the 18 max amp Ducati VR beyond its capacity.
> The main, and frankly the only hi amp item needed today, is the pitot heat
 in a solid state IFR aircraft.  That is where a 40 amp alternator, which is
 belt driven, is necessary; because in the pattern, doing 80 knots at 4000 R
PM the Ducati is barely keeping pace on a VFR day with normal radios/transpo
nder and the like (Rotax says it supplies 13.5 volts at 18 amps at 4000 but d
on=99t count on it).  If you have a 914, each pump is 2-3 amps and the
 TCU and servo another .2.  Add Pitot heat, electric gyros, autopilot, 5 wat
t radios, old 2.5 amp transponder, encoder, incandescent 100,000 candle powe
r landing light, and incandescent Whelen Strobes,  you will need 30 amps and
 a robust battery just to drive all that.  Of course you will need the 60 am
p if you add your heated seat cushions, electric snow suit, dual iPads and s
tereo system.  But you will be =9Cstylin=9D.
>  
> Problems with the Belt Driven Alternator is you must change the cowl, add a
 spacer to the prop drive lugs for the pulley flange sometimes, deal with no
ise from the alternator (magnetic and electronic from the alternator) and of
 course the weight.  If it is a low power belt drive alternator, you may nee
d to split the main bus into two and add a bus tie in the event of loss of o
ne alternator.  Wiring designs for switching alternators/bus ties and system
 degradation (if the main or aux alternator is lost), is necessary.  Been th
ere, done that!  Time consuming, but necessary documentation, and it works.
>  
> Pitot Heat:  I=99ve installed Angus, Dynon, old Piper units and they
 all draw 6-10 amps when on at full blast.  Nice thing about the new ones is
 they have thermostats so unless cruising in severe icing, they only draw a c
ouple amps.  But that initial turn on and cruising in sub freezing temps wil
l get you back up to the that max of 6-10 amps.  No one has figured out anti
-icing for the wings and prop to date.  I=99ve commented on the backup
 static source recently.
>  
> Consider this:
> Led Lighting  (high power landing light is 2.5 amps, and wing lighting is .
6 amps with continuous strobe)
> Interior lighting of LED post lights (I know they are not sexy) is negligi
ble).
> Modern solid state radios pull .5 amps.  Trig is one, and they do not requ
ire cooling air.
> (Cooling fans draw a max of .5 amps and if a unit needs one, it draws too m
uch power.
> Mode S transponders today are all digital and pull .5 amps max.
> Gyros are a thing of the past.  A solid state EFIS is all that is necessar
y.  It pulls only about .6 amps if you are a frequent button pusher.  Leave i
t alone and it drops to .1 amp.
> Engine monitors are built into the EFIS systems and pull next to zero.
> Autopilots draw a max of 2 when working hard and .5 at cruise.
> Ipads tend to draw about 2 amps when working as a nav device.  More if nee
ding a charge and working hard.
> Aux boost pumps adds 2-3 amps when under load, so figure 4 amps at 4000 RP
M in a 914 on downwind with both on.
>  
> Trim and flaps are momentary draws so I=99m not counting them.
> Batteries are now stronger and longer lasting, and even I am warming up to
 the Li ion batteries.  Heck, put in two.
>  
> At night in the weather, with idle RPM you are on the battery only normall
y so if the battery was down a bit and on landing roll out you key your old G
armin radio, expect the incandescent lights and radio to cut out, leaving yo
u dark and quiet on the runway.
>  
> So the amp draw is in the range of  9-10 amps until you turn on the pitot h
eat and landing lights then you are at 18-20.  If you want a fully IFR Europ
a to meet the required equipment for IFR, you must have a belt driven altern
ator at this time to provide the necessary amps at lower RPMs.  Until the ex
tra alternator coil gets approved on the back of the Rotax, you are stuck wi
th the mods I discussed above.
>  
> In Europe, you do have the new guys: FLYGAS who have reportedly added a se
cond set of coils and rotors to the back of the Rotax 9 series.  The prototy
pe was clean and neat looking last time I looked. 
>  
> Circuit design is fairly easy for dual alternators, even if you split the b
uses.  You can review Bob Knuckles and go from there.  I haven=99t put
 customer circuits I design on my website but I=99m available to send c
opies.
>  
> In the use of Vertical Power and other so called easy plug and play wiring
 units, I am mixed on them.  To save panel space or extensive panel mods to e
nlarge the panel face for circuit breaker panels, I have used the very inexp
ensive and reliable circuit board made by EXP.  I do not use their face plat
e.  I install my own switches and relays where I want them.  I also mount it
 securely, fab a cover panel (I don=99t need some loose nut falling in
to a circuit board) and apply cooling air as PTCs do warm up which affects t
heir tripping point.  I do not like the EXP annunciator panel but it works (
except for amps)  and it has a built in surge protector.  Weight is .6 pound
s with my cover and D sub plugs.
>  
> I spoke to Vertical Power at Sebring last month.  The unit weighs in at 2 p
ounds, and their power hook up box is 1.6 pounds (from memory)  The boxes ar
e large (so where to put them is a problem) and their supplied wire bundles w
ith D subs are heavy as sin and use straight connectors so the wire bundle b
ending as well as box placement must be planned very carefully.  A sport air
craft is already 5 pounds of crap in a 3 pound bag so I just don=99t h
ave room for these huge boxes. 
>  
> Remember, if a system is automatic, you have lost control.  As with power p
anels, don=99t try to isolate one circuit to test during the build wit
hout planning your plug circuits to allow a bypass of all the rest of the ci
rcuits.  If all wired direct, it is all hooked up or nothing.
>  
> I prefer to teach my clients how to wire, the tools and wire necessary to d
o the job right.  Try to make everything serviceable inside the panel and th
e panel a breeze to remove (of course nobody but me wants to do it as it is p
lugs and screws.)  I have also found, if it is convenient and automatic it i
s also expensive, heavy, and seems to always require extra support.  Sometim
es dumb simple systems, well documented, are the least troublesome.  The cli
ent understands and knows his panel, and in the event of a problem, is more c
omfortable with troubleshooting.  Remember, if you plan it to be serviceable
, it will never fail.
>  
> Just my opinion.
>  
> Bud Yerly
>  
>  
>  
>  
>  
>  
>  
> Sent from Mail for Windows 10
>  
> <BB4E755A5CBB4A02897F8771CFD68B49.png>
> From: Mike Gregory <m.j.gregory@talk21.com>
> Sent: Saturday, March 10, 2018 5:40:15 AM
> To: europa-committee@googlegroups.com; davidjoyce@doctors.org.uk
> Cc: 'Bud Yerly'
> Subject: RE: [europa-committee] RE: Europa-List: Re: Vertical Power VP-X P
ro
>  
> David,
>  
> Yes of course you may pass that on to Alan =93 I don=99t think
 I=99ve said anything libellous about VP, and the points made on the A
eroElectric list are open to all who care to subscribe.  I believe very much
 in careful consideration of factors such as reliability and maintainability
 before installing anything that has not a track record for application to t
he Europa. While cost/benefit is also a consideration, I would be much more c
oncerned about ease of fixing to get home if anything went wrong when far aw
ay from specialist support.
>  
> I am copying this to Bud Yerly, and would welcome any comments from him, e
specially if he has fitted such a packaged system to a Europa.
>  
> Best wishes,
>  
> Mike
> Dr Mike Gregory
> +441480 451655
> +447885 355765
>  
> From: 'Peter Jeffers' via europa committee [mailto:europa-committee@google
groups.com] 
> Sent: 10 March 2018 09:40
> To: davidjoyce@doctors.org.uk
> Cc: europa-committee@googlegroups.com
> Subject: [europa-committee] RE: Europa-List: Re: Vertical Power VP-X Pro
>  
> Hi David ,
> I did suggest a while ago that he contact the LAA wrt his proposition rath
er than receive unverified information from club officials.
> Pete
>  
> From: davidjoyce@doctors.org.uk [mailto:davidjoyce@doctors.org.uk] 
> Sent: 10 March 2018 08:48
> To: Mike Gregory
> Cc: 'Peter Jeffers'
> Subject: RE: Europa-List: Re: Vertical Power VP-X Pro
>  
> Mike, Are you happy to pass that on to Alan? Might save him some bother. D
avid
> 
> On 2018-03-10 00:32, Mike Gregory wrote:
> 
> Hello David,
> I had a discussion with Francis some years ago about the EXP-Bus, which yo
u no doubt are aware was an earlier system providing an integrated solution t
o electrical control and distribution.  We agreed that it was not something w
e would wish to encourage for permit aircraft, as such a system has the pote
ntial to give trouble that would be difficult to diagnose and fix if the sof
tware or hardware went wrong.
> There was a lot of discussion on the AeroElecric list in 2016, typified by
 the contributions copied below from Bob Nuckolls and Peter Pengilly, two pe
ople whose advice I respect.
>  I share the summary view expressed by Peter Pengilly at the end of his pi
ece:
> "So we have a device of unknown quality passing data to a second device of
 equally unknown quality to control a function that we really need to work c
orrectly all of the time. That is rather too much trust to put in people I h
ave never met and who are unwilling to describe how they ensure their design
 goals are achieved in their products.
> 
>  "However good a VPX is at managing an electrical system, from my perspect
ive this type of function is taking unnecessary risks for very little gain. I
t is also expensive when a few fuses will carry out the same job."
> 
> If someone wants to spend the money, then no doubt they could get LAA appr
oval to install such a system, but even with this newer system I still would
n't encourage it =93 and certainly not if the reason for adopting it i
s that the builder doesn't understand electrics and wants to "simplify" his e
lectrical build.
> 
> Best wishes,
> 
> Mike
> Dr Mike Gregory
> 01480 451655
> 07885 355765
>  From: davidjoyce@doctors.org.uk [mailto:davidjoyce@doctors.org.uk] 
> Sent: 09 March 2018 15:23
> To: Mike Gregory
> Subject: Fwd: Europa-List: Re: Vertical Power VP-X Pro
> Mike, Do you have the time to offer an opinion on this? David
> 
> -------- Original Message --------
> 
> Subject:
> Europa-List: Re: Vertical Power VP-X Pro
> Date:
> 2018-03-09 10:19
> From:
> "alan_hunter1664" <alan_hunter1664@yahoo.co.uk>
> To:
> europa-list@matronics.com
> Reply-To:
> europa-list@matronics.com
o.co.uk>
>  
> I'm going to send this to my inspector but I would be grateful of any comm
ents on the attached prior to this. Does this look reasonable as an avionics
 installation for a Europa? there will be a standby altimeter & ASI which is
n't shown on the diagram, also I haven't numbered the cables yet either
>  
> Thank you in advance
>  
> Read this topic online here:
>  
> http://forums.matronics.com/viewtopic.php?p=478518#478518
>  
> Attachments: 
>  
> http://forums.matronics.com//files/electrical_wiring_diagram_413.xlsx
> http://forums.matronics.com//files/electrical_wiring_diagram_151.xlsx
>  
>  
> From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelect
ric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III
> Sent: 26 March 2016 20:53
> To: aeroelectric-list@matronics.com
> Subject: Re: AeroElectric-List: Re: Vertical Power X-VP Pro or Sport
>  
> At 10:11 AM 3/24/2016, you wrote:
> 
> I have wondered about 2 issues w/ VP systems:
> 
> 1. The all-your-eggs-in-one-basket issue.  If the unit fails the aircraft i
s down and you, the owner, cannot fix it.
> 
> 2. The system adds several layers of complexity & cost to the relatively s
imple task of power distribution.
> 
> I'm curious if owners of the system share those concerns and how they addr
ess them.
> 
>    We've had discussions about these kinds of systems on numerous occasion
s over the years that began with relatively innocuous products like the EXP-
Bus
> 
> http://tinyurl.com/jucvcar
> 
>    and sort of reached an apex with the Vertical Power products. Based on m
y experience in the TC aircraft world, I've always assessed such offerings f
rom two perspectives:
> 
>    Cost of ownership:  Over the lifetime of the airplane . . . from the da
y you plunk down your credit card to order the product until the time you se
ll or scrap the airplane, what is the $service-value$ when compared to the $
acquisition/maintenance value$?
> 
>    Part of that cost of ownership has to include cost to acquire and insta
ll the system. Our airplanes are not very complex. A review of the Z-figures
 describes a range of complexity from ultra-lights to a Lance Air 4P.  If on
e chooses to wire up fuse blocks and flip switches purchased at the hardware
 store, the cost of acquisition can be quite nominal . . . but the number of
 tinker-toys is greater and they are not combined into plug-n-play modules. 

> 
>    However, no single component is very expensive hence easily and cheaply
 replaced when it reaches end of service life. Further, nothing is 'automati
c' . . .
>    we are encouraged to be technically cognizant pilots, not appliance ope
rators. Even when you consider the totality of automation offered by any air
plane super-system, what percentage of your block-to-block trip time is cons
umed doing those operations yourself?
> 
>    Once you've deduce the demands on your time and attention for manual op
erations, how much are you willing to pay to have those things done for you?

>    The other side of the coin begs the question for how much understanding
 and in-flight cognizance is discouraged or even denied to you when you let t
he software do it for you?
> 
>    I am reminded of a line from "The Right Stuff" attributed to Deke Slayt
on of the original astronauts after discovering that they were being selecte
d to be mere passengers on the first US manned space flights.
>    
> Deke Slayton: What Gus is saying is that we're missing the point. What Gus
 is saying is that we all heard the rumors that they want to send a monkey u
p first. Well, none of us wants to think that they're gonna send a monkey up
 to do a man's work. But what Gus is saying is that what they're trying to d
o to us is send a man up to do a monkey's work.
> Us, a bunch of college-trained chimpanzees! 
> 
>    Animals had been used in aeronautic exploration since 1783 when the Mon
tgolfier brothers sent a sheep, a duck and a rooster aloft in a hot air ball
oon. We've come a long way since then . . . we KNOW that high speed motion a
t altitude is not inherently
>    hazardous . . . we also know that MOST unhappy days in the cockpit have
 roots in lack of knowledge, skill or just inattention.
>   
>    I started the AeroElectric Connection in 1988 based on an observation a
t OSH suggesting that the electrical system was the least understood compone
nt of the OBAM aircraft.
>    The 'Connection grew out of the notion that the whole universe runs on s
tone-simple-ideas in physics. All creativity is a study in properties of mat
erials and  management of energy. Ergo, if you can learn to make bread or re
pair your lawn mower, you can also learn to how to craft and operate a machi
ne that would have scared the socks of the Montgolfier brothers with less ri
sk than their first living passengers might have been exposed to.
> 
>    If Goggle has their way, self flying airplanes are right on the heals o
f self-driving cars. No doubt there will be customers for those products. Do
n't know why everyone else likes to fly but I do it because I'm a pilot with
 an intense interest in how and why the machine works while maintaining it w
ith a minimum of interference, cost and down time for repairs.
> 
>    Probability for electrical system malfunctions being root cause for ben
t machines and/or people are vanishingly small. Yet many of our brothers 'wo
rry' about the electrics for what I'll suggest are two primary reasons. Lack
 of understanding combined with the relative frequency of 'dark n stormy nig
ht' stories in the aviation rags that speak to electrical systems issues whi
le illuminating the pilot's ignorance.
> 
>    If installing a 'push-button' electrical system is attractive, then do s
ome soul searching for the motivation  If it is a ploy to avoid a need to un
derstand . . . or just a love of technological bells and whistles. If money i
s no object and having and airplane with lots of nice displays is a goal, th
en by all means. But if money is tight but you're worried about the artful c
ombination of simple-ingredients in a recipe for success, then allow me to s
uggest that the learning curve is steep and not difficult. If push-button ut
ility is the goal, then know that virtually ALL products ranging from EXP-Bu
s to Vertical Power do perform as advertised.
>    Choice of products is all about how large the bells-and-whistles bucket
 is.
> 
>    Another consideration is cost of ownership for the fielded system. When
 it breaks, what are your options for getting it back in service, at what co
st and down time on the airplane? There's a cost of competence and confidenc
e when the root cause of failure is not understood and remedy is beyond your
 control. A situation that seldom occurs when your recipe for success is a c
ollection of simple components from the hardware store.
> 
>    The second benchmark speaks to failure mode effects analysis and mitiga
tion that asks the following questions:
> 
> 1. How many ways can this part fail?
> 
> 2. How will each failure affect system operation?
> 
> 3. How will I know it failed?
> 
> 4. Is the failure pre-flight detectable?
> 
> 5. Is failure of this part, in any failure mode, likely to create
>    a hazard to flight?
> 
> 6. Will failure of this part be likely to overtax my piloting
>    skills for comfortably terminating the flight?
> 
>    When you're looking at a nice touch-screen with lots of pretty colors, m
ost of the answers to the above are not known to you. On the other hand, a s
mall box of fuses, switches, relays, terminals and wire has no secrets . . .
 and allows the builder to comfortably asses all the above and the important
 SEVENTH question:
> 
> 7. Is there any failure with effects that influence more than one system?
> 
>    Having good answers to the above is foundation for a failure tolerant, l
ow maintenance, minimum cost of ownership product with minimized risk. That'
s how we built Beechjets and Bonanzas . . . machines I like to think of as a
irplanes for pilots.
> 
>   Bob . . .
> From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelect
ric-list-server@matronics.com] On Behalf Of Peter Pengilly
> Sent: 26 March 2016 00:08
> To: aeroelectric-list@matronics.com
> Subject: Re: AeroElectric-List: Re: Vertical Power X-VP Pro or Sport
> 
> --> AeroElectric-List message posted by: Peter Pengilly
> 
> --> <peter@sportingaero.com>
> 
> That's a rather angry post, let's try to take the emotion out of this disc
ussion.
> 
> Looking at the flap and trim control only. The VPX is a software driven ma
chine. It takes switch inputs, recognises the pilot has requested a certain a
ction and switches power to a service. The logic is executed by software. I d
o not know what standard was used to design, code and test the software. The
 VPX has full control of the flap and trim motors and can drive them to full
 deflection at any time it chooses, either would be rather bad news in most a
ircraft, particularly at cruise speed . If that were to happen at a slow rat
e I believe the only way to stop it would be to shut down the whole VPX - I'
m not even sure if that is possible. I hope there are some protections built
 into the VPX to prevent un-commanded movement, but I don't know as I cannot
 find that data in the public domain. Therefore we only have the assertions o
f the designers that motor run-aways will not happen.
> 
> EFISs are also software driven machines, all of the common uncertified EFI
Ss are in the same boat - I have asked the manufacturers how their software w
as written, they have declined to answer.
> 
> So we have a device of unknown quality passing data to a second device of e
qually unknown quality to control a function that we really need to work cor
rectly all of the time. That is rather too much trust to put in people I hav
e never met and who are unwilling to describe how they ensure their design g
oals are achieved in their products.
> 
> However good a VPX is at managing an electrical system, from my perspectiv
e this type of function is taking unnecessary risks for very little gain. It
 is also expensive when a few fuses will carry out the same job.
> 
> Peter
> 
> On 25/03/2016 20:35, Kelly McMullen wrote:
> 
> > --> AeroElectric-List message posted by: Kelly McMullen
> 
> > <kellym@aviatingcom>
> 
> > 
> 
> > Your assertion that the flap and trim in the VPX is dependent on EFIS
> 
> > is flat incorrect. It only uses the airspeed to control how fast the
> 
> > trim motor runs or to prevent exceeding flap airspeed limit, which is
> 
> > something other systems don't do. You apparently missed that I have
> 
> > independent power backup to EFIS should something fail in the VPX. I
> 
> > also have an independent EFIS that isn't dependent on ship's power at
> 
> > all, which has battery life close to fuel range of the aircraft.
> 
> > The likely problems a failure of the VPX would cause is same as loss
> 
> > of alternator. I suppose a circuit could go crazy, so you turn the
> 
> > master off. I don't trust the VPX any more than I do the alternator or
> 
> > traditional power layouts. I've seen the failure of voltage regulators
> 
> > and overvoltage systems and the havoc they cause. If you have planned
> 
> > correctly, there is no more risk than a traditional fuse and circuit
> 
> > breaker design. Asserting there is more risk has no demonstrated basis
> 
> > that I have seen. If you have evidence, please educate us.
> 
> > 
> 
> > On 3/25/2016 12:23 AM, Peter Pengilly wrote:
> 
> >> Flame suit is on and I stand by all of my comments. As VPX has
> 
> >> control of trimou  and flap motor based on an input from the EFIS any
> 
> >> error in this chain could cause significant problems. With an IFR
> 
> >> aircraft it is just about essential to have an alternative power
> 
> >> supply to the attitude instrument(s), outside of the VPX.
> 
> >> 
> 
> >> I have had 25 years experience working with airborne software
> 
> >> writers, I don't trust them as much as some here seem to!
> 
> >> 
> 
> >> Peter
> 
> >> 
> 
> >> On 25 Mar 2016 02:52, "Kelly McMullen" <kellym@aviating.com
> 
> >> <mailto:kellym@aviating.com>> wrote:
> 
> >> 
> 
> >>     --> AeroElectric-List message posted by: Kelly McMullen
> 
> >>     <kellym@aviating.com <mailto:kellym@aviating.com>>
> 
> >> 
> 
> >>     Misconceptions from lack of familiarity.
> 
> >> 
> 
> >>     On 3/24/2016 4:15 PM, Peter Pengilly wrote:
> 
> >> 
> 
> >>         - The sales pitch is that designing electrical systems and
> 
> >>         wiring up is
> 
> >>         difficult and this box makes it easy. I don't agree with these
> 
> >>         statements!
> 
> >> 
> 
> >>     Never perceived it that way. It does simplify the wiring.
> 
> >> 
> 
> >>         - It provides limited opportunities for expansion There are a
> 
> >>         limited
> 
> >>         number of circuits available, once these are used up any
> 
> >> additional
> 
> >>         services will have to be protected by conventional fuses or
> 
> >> circuit
> 
> >>         breakers - seems to make the box a little pointless.
> 
> >> 
> 
> >>     The Pro version is not that limited, is intended for full IFR panel
,
> 
> >>     which is what I have, with several pins available for expansion.
> 
> >> 
> 
> >>         - The box is expensive compared to fuses.
> 
> >> 
> 
> >>     Not when you have to physically install each, do the labor to
> 
> >>     replace any that blow, etc. I had full hardware priced for CB &
> 
> >>     fuses system...easily $500. Add 100 hours of labor to design, and
> 
> >>     create panel of fuses/CB etc, and you are over price of VPX.
> 
> >>     Advanced Flight Systems thought enough of the concept that they
> 
> >>     designed their own box.
> 
> >> 
> 
> >>         - Combining many functions in one box means that any failure
> 
> >>         becomes a
> 
> >>         significant event rather than just an annoyance.
> 
> >> 
> 
> >>     AFAIK, unknown event so far.
> 
> >> 
> 
> >>         - The software is designed and coded to an unknown standard and

> 
> >>         tested
> 
> >>         in an unknown way, neither of which engenders confidence.
> 
> >> 
> 
> >>     Have had no issues, have been operating the system for about 3 yrs.

> 
> >> 
> 
> >>         - The standAFAIKards used to design, build and test the hardwar
e
> 
> >>         are not easy
> 
> >>         to discern, leading to questions on the long term reliability.
> 
> >> 
> 
> >>     Theoretical, where is data of unreliability?
> 
> >> 
> 
> >>         - Using the box to control trim and flaps using an input from a
n
> 
> >>         EFIS
> 
> >>         places a huge amount of trust in the software writers where a
> 
> >> fault
> 
> >>         risks potentially very serious consequences.
> 
> >> 
> 
> >>     Does not use EFIS for input beyond airspeed, only outputs trim/flap

> 
> >>     position to EFIS. Position comes from trim motor or a position
> 
> >>     sensor. Power goes to trim/flap motor. No extra boxes needed for
> 
> >>     trim speed control, runaway protection, wig wag lights.
> 
> >> 
> 
> >>         - Those an have chosen to use this box can be very firm in thei
r
> 
> >>         support, and intolerant of those who present an alternative
> 
> >>         view, flame
> 
> >>         suit on!!
> 
> >> 
> 
> >>     Only intolerant of criticism generated by lack of knowledge, not
> 
> >> facts.
> 
> >> 
> 
> >>         On the supportive side, the designer (Marc Ausman) is a huge
> 
> >>         supporter
> 
> >>         of homebuilt aviation, and is a director of EAA. The real world

> 
> >>         reliability seems to be reasonable.
> 
> >> 
> 
> >> 
> 
> >>     Data behind that assertion???
> 
> >> 
> 
> >> 
> 
> >>         My advice would be to start by listing all the electrical
> 
> >>         functions you
> 
> >>         want in your aircraft, then which are key to the safe completio
n
> 
> >>         of a
> 
> >>         flight. If you have (m)any of these are you content to
> 
> >> entrust the
> 
> >>         operation of these functions to the VPX? If you are list the
> 
> >> cost of
> 
> >>         using fuses against other means. Install equipment for as
> 
> >> reason!
> 
> >> 
> 
> >>         Peter
> 
> >> 
> 
> >>     No problem with your recommendations, but how electrically dependen
t
> 
> >>     is you aircraft? How critical are items beyond engine ignition? If
> 
> >>     critical, you need some independent backup. Are you not planning fo
r
> 
> >>     portable GPS and Com radio for back up?
> 
> >>     You can't fly commercial activities, so how much pressure is there
> 
> >>     to fly in solid IFR? Why would you design electrical system that is

> 
> >>     critical to continued flight without independent dual systems?
> 
> >>     The VPX offers a lot of convenience and flexibility without hardwar
e
> 
> >>     issues. want to switch an item from buss A to B? Just a software
> 
> >>     reconfigure. Want to change landing lights wig-wag function? Just
> 
> >>     software. Ditto for trim or flap limits. Have you flown an example
> 
> >>     of your aircraft model? Do you know how trim dependent it is?
> 
> >> 
> 
>  
>  


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