Suggestions for "laying in the wiring harness"

If you upgrade to the wiring harness that VP can provide you, here are a couple of observations.

A) Make sure you know how the connectors work and prove to yourself that you can unlock one and redo it without damaging it. Do this prior to "laying" in the harness

B) I'd suggest this order for doing the wiring around the VP harness

• Lay in the harness
• Group wires together that go to similar locations within the airframe
• use tape or tie wraps to loosely bundle the groups mentioned in item 2 above
• Determine penetration points where needed and basic wiring attachment points (this won't be all of them and don't do all the bundling and tie-wrapping yet)
• Determine your ground points and install the ground connection blocks
• "lay in" the ground wires parallel to the power wires from the harness and use the similar paths, penetrations, attach points, etc
  

C) After step (B) above you should have the basic power harness installed. Now focus on the other "signalling" functions (e.g. flaps, trim, switches, stick grips, etc)

D) Finally install and connector all the other functions (e.g. autopilot signals, serial inputs/outputs, audio, etc)

Some of these steps can be swapped depending upon how complex your equipment is, but the (B) step in the order specified is what worked the best for me.

Wires, wires, everywhere

Ok, catching up on a few pictures... Harness bascially "layed in", determining where to put tie down blocks.


Other CU in similar state


Inside the tunnel


Center console


Out the front and Avionics shelf



I'll catch up on a few more pictures later today, during which time I'll be working on grounds and basic routing for "fat wires" - which will wait for their final location until weight and balance time.

LPW - latest version

In case you want to look at mine, here is the link to the latest and greatest... You'll see it's version 14 :)... It did take some thinking in a couple of spots plus as I was one of the first to be putting this in a Lancair, we tweaked some things based upon the way the Lancair Flaps system works and perfected the way the canopy seal works with the VP system.

At least it will give you another example to play with... But mind you don't enter it exactly unless you know what you are doing. :)

Lastest LPW

Impressions (part 2)

I was thinking about what I wrote yesterday and realized that maybe I should drop some info in the Blog about what to do differently while Planning your VP based airplanes.

a) Component placement - one of the first basic things that you'll need to thing thru is where will you put things. Not only the VP components, but also the individual devices that you'll control. When you build your LPW, you'll need to spec lengths of wire and it's certainly eaiser to make them longer and cut them off to what you need than it is to have one be short due to revised placement and then need to "splice" two wires together. This isn't a VP specific action btw, it would need to be done either way, but if you are going to buy a VP harness, you'll need to think thru this up front.

b) Grounds - Especially if you are building a composite airplane, you'll need to think thru grounding. The VP harness will give you want you need to provide power, trim, flaps, and some control functions, but it won't give you provisions for specific device grounds. If you design "cluster" spots for components to terminate their grounds that will help. Then you can use either ground terminal blocks, or other types of clustering to provide the individual grounds and then take that ground back to the central ground buss between the engine and batteries

c) Wire sizes obviously, but you'll need to do that no matter what

d) While in a traditional environment you need to think thru what goes on what buss. The concept of a main buss and an endurance buss is slightly different with a VP environment. Each CU actually has it's own "endurance" buss back to it's battery, so what you actually have to think thru in a VP environment is your "load shed" plan. This means that if you have some form of electrical failiure (alternator, battery, etc), that you think more about what devices you would want on in which emergency situation than you do what buss to put devices on or what contactor configuration would be needed to power a specific device. It is good practice however to take devices that are "dual in nature", like 2 EFIS displays and put one on one CU and the other on the other if going a VP Duo system.

e) Switches and overrides - *make sure* you read the installation section on these, they allow your system to become extremely flexible in a failure situation. VP has thought thru most of the scenarios and thru a combination of switch and override modes you can make your solution for any emergency or trouble simple

f) Checklists - at some point, you'll need to develop a checklist that can be used for each flight mode. This will make it easier to establish "flows" and reduce cockpit workload.

g) Power connectors - once you get your harness, make sure you learn how to add or move wires if needed. It's easier to learn this skill before you put in the harness than after when you may be constrained on space. Also there are a couple of "help me's" that the guys at VP have created to show you what the connectors should look like when you open them, what not to do and how each should work. Get *very* familiar with the documentation section of the VP site.

h) Avionics Master - let's see, what do they say on the Sopranos.... fugetaboutit, ya don't need it with VP, plus you get added benefits in that only those things that you want on during the particular "Mode" are on. Huge benefit if trying to start an engine on a 12v system with EFIS technology that might be sensative to turning off when voltage drops below a certain threshold.

i) Items you can ignore! :) - I say that tongue in cheek. To some extent you can ignore the "fancy feature devices". For example with VP you no longer need to think about what you need to buy to provide flap steps and control; trim authority, control and speed; light dimming, control and functions; annunciator panels, control, audio prompts; external triggers like canopy open, baggage open, etc; Most of these are included in the fuctions of the VP 200 systems and some are included in the 100 systems. This saves you a significant amount on items that you'd normally want to purchase separately in order to facilitate these functions.

Ok, that should get you started. There are 2 primary rules in getting starting with VP. A) RTFM - Read the darn installation manual; B) RTFMA - Read the darn installation manual again! Then if you have any question, get on VP's forums and post a question or give Marc and team a call.

VP's Forums

Impressions so far (part 1)

I spent a few minutes (I am after all trying to get this bloody thing flying) in retrospect, thinking about the differences between the original way I was going to wire the airplane and the way it will end up being wired (I'm sorta in the middle/end of that process right now).

Last year, I spent what seemed like forever developing a "wirebook" to aid me in wiring the airplane. This was before I met Marc and the gang at Vertical Power. My original information and wirebook can be found here .

Since that time I've got a hole new appreciation for the amount of effort that original intent would have taken. I've also learned of some of the inflexibility that it would have caused. And also some of the weight that it would have generated. Which, by switching to the VP DUO, I won't have. Here are just a few of the examples.


a) Panel wiring and weight - this is how the back of just the "breaker" area would have looked if I had gone down the path of doing panel breakers. Each device that required a breaker would have required a lenght of wire to be run from the device to the breaker and breaker to battery contactor buss.

b) Fat wires - see those fat wires in that picture above. Depending on where your battery(s) were located, you'd have to run a fat wire from the Alternator(s) to the battery(s) and then up to the panel where usually the breakers ans busses are constructed. In my case, the batteries will be in the tail, so that represents a pretty huge savings in weight that I won't need to do.


c) Space constraints - originally, you have to think in terms of what I'll call a "clustered" power environment. I also needs to be packed into the panel area. I was always trying to constrain space to allow for maximum flexibility around wiring on the back of the panel. This would provide the most flexibility for service down the road, but at the compromise of the smallest area to work in. Ever noticed that you always look at the back of a panel, when you look at some elses handiwork and wonder how they got all that stuff in there. With VP, you end up in a more "distributed" power environment, one where there is a central distribution point, but it doesn't have to be located behind the panel if you elect not to.

d) the other area that your don't really think about centers around the amount of effort required to determine the size and length of wires, how many things need to be connected and where they will get their power. The tools that VP have developed thru the use of their LPW (Load Planning Worksheet) and installation documentation because a huge contributor in saving me loads of time as I retooled and switched from the "old school" to the new VP environment. It created a logical tool to organize your thots, determine distances, wire sizes, breaker sizes and then utimately culminated in a pre-made wiring harness. In my case there are close too 100 wires that all I had to do was "lay them in" and connect them up.

I've read recent posts about people being "scared" to tackle wiring their own airplane and especially their own panel. With the VP approach and their tools, you can't go wrong. Oh, and did I talk about their support, it's excellent.





I've got some more to add to this stream of thot, but for now here's a close up of my panel, it's lack of breakers, switches, etc for you to look at. Me - I want to go work on my airplane.... More with new pictures later.

Serial Interconnects

In wiring my panel, I needed to build a drawing of all the serial interconnects. In the process, I provisioned it for what I believe would work with a GDL-90 ADS-B receiever.

I also have many things that share a common sources.. For example, I have 3 if not 4 items that take NMEA from the G496 and also about the same from the GPS data from the Chelton GADAHRS.

I devised a way to use "DB" type connectors as a poor mans serial buss. I'll take the source side and daisy chain together the numbers needed, and then on the destination side, the only common pin will be the shield. This should allow easier swapping as needed between the various serial devices. Hopefully, I won't have to swap, but just in case, this method seemed to be the most simple to utilize to facilitate all the sources and destinations.

Anyway, back to the drawing. You can get it from my web site - here

It is color coded for the various interconnects... It also shows the locations of the serial busses and reflects a panel design using CPC connectors to facilitate simple removal of the entire panel if needed.

Hope this helps someone, I know it certainly will help me.

I didn't think this day would ever come!

As it relates to those very large holes on the left side of my panel. I didn't think the day would come where I'd actually have things stuff in them. And least you only look there.... Lookie, lookie, lookie, what the UPS man dropped off at my house today... Notice the right most Large Holes have items in them as well!!! Yep, that's the VP DU as it's called (Display Unit), and the SP below it (Switch Panel). Real versions with real electronics inside.

Oooooo, Ohhhhhhh, it won't be long now!

VP Duo - Shipped today!

Got notice from VP that the *real* red boxes, display unit, and switch panel have shipped. Should get them early next week. I also sent them my Pinpoint GADAHRS to do testing with GPS and ADC data. Hope that goes well.

Real boxes, real Display, real close

I got the following picture from Marc today at VP. Looks like actual hardware is nearing delivery status. Oh man, this is getting exciting. Things are starting to come together and lights are starting to turn on :)...

Can't wait!