Sunday, December 28, 2008

Electrical system work

I had hoped to spend the weekend working on finalizing the electrical system for N614EF. I've tried; I really have. I put together the load analysis spreadsheet for the Vertical Power system, and I realize the instructions need to be "dummified" more. Why? Because I'm a dummy, not an electrical engineer.

I'm a writer and if you could design and install an electrical system by turning a phrase or two, I'd have it done by now. To people well-schooled in electronics, a schematic is much easier to implement than subject-verb tense agreement. Everybody's different.

It's still not clear to me, for example, how I supply always-on power to the Dynon unit (which keeps the clock updated etc.). As near as I can tell, the wiring would require a line from the battery, which tells me that there should be some sort of battery buss somewhere under the subpanel somewhere, in a fashion that avoids the Vertical Power control unit altogether.

Vertical Power's Marc Ausman -- a really good guy -- said on VP's support forum, "...anything else will will be powered from the VP-50 or the aux bus (like starter contactor power) which is wired downstream of the battery contactor." I get that, I guess. But it's still not clear to me what that looks like when I lean over and look at someone's RV subpanel.

And therein lies the problem for people like me. We learn by actually SEEING things. I can ruminate for hours over what a schematic tells me about what to do with shielded cable, but it's a lot easier for me to look at that schematic, then go downstairs and pull out the Dynon harness and see what SteinAir did. Voila! Now the schematic makes sense because I saw what it looks like in real life.

This is a typical electrical system schematic:

After spending weeks looking at that, it finally made sense what the philosophy of it was. But what does it look like in an RV airplane? I couldn't tell you, but because this is one of the most common installations, there are enough builder Web sites out there to give me a clue.

And this is also why Van's electrical system instructions are so good for people like me. It approaches building the system this way:

1. Start here.
2. Mount this thing there.
3. Mount the other thing here.
4. Run a wire from this location, to that location and back to this location.

See what I mean? It doesn't give me philosophy, it gives me instructions. And because Van's is helping you build an airplane, they don't just concentrate on their own product and give you only the information pertaining to its product, they tell you the whole shootin' match.

In other words, they're focused on the whole, not on the parts.

Here's an example. Dan Checkoway's excellent Web site carries pictures of the firewall and such things as the ANL limiter. Now, I've read the AeroElectric Connection -- about 13 times. And it sort of makes sense in its philosophical ways, but a site, like Dan's, which says "put this here, put that there, the hambone is connected to the leg bone" is the way instructions should be put together for airplane builders like me.

Unfortunately, that's not possible with a product so new as Vertical Power. Don't get me wrong, it's a great product and the instructions are well written, but because it's such a new product, there aren't any Web sites out there that do for it what sites like Dan's, or Walter Tondu's do for the traditional electric system.

I was out at the hangar yesterday trying to figure out where to mount the Vertical Power-50 control unit. With a traditional unit, you enter your search terms in Google, check however many of the 1,000 RV builder Web sites you want, and do what they did. You can't do that with the Vertical Power system. There's only one RV-7 builder site. Bernie Daenzer and Alex Lichtensteiger's , and they're using the VP-200. Also, it's not a step-by-step Web site.

So, I never really came up with a good solution, partly because I don't know what else I need to fit under the subpanel because there aren't any Web sites with pictures and step-by-steps of installing a complete electrical system.

So what to do now? I have to think some more about whether I'm the right guy to be one of the first builders to install a VP-50. If I am, I'd put together a Web site on how to do it. Or do I want to punt and just go back to the tried-and-true traditional electrical system, and take advantage of the online resources that, as I indicated, are available? A lot depends on the answer to that. I can't send the instrument panel out to be cut until I know whether it will have circuit breakers, for example.

One thing that's great about the VP boys, however, is when you send them your load planning worksheet, they send you back suggestions for how to improve your plan. You gotta love that!

Here's what changes Marc made to mine (including catching my mistakes):

-Swap the EFIS and 296. The loads were not correct, and Dynon recommends a 3A breaker.
- The flaps draw 4.4 amps under load. So I put them on a 10A circuit. Usually a 5A CB is fine, but sometimes you need more.
- The flaps need to have their own external flap switch, the VP just provides power (unlike the VP-100 and 200 which actually drive the flap motor directly). See VP-50 wiring diagram.
- What trim systems are you installing? The trim is not filled in (some blacked out).
- Do you have a 296 or 496? It is unclear. In either case, it is on its own pin
- I put the aux bus items each on their own pin. You have extra pins.
- I assume the ext warning light is for something else and you just need power? It is now on J8-23

Odd, I don't remember adding an exterior warning light. I don't need it, though.

Here's what my spreadsheet looks like:

Once I fully understand the Vertical Power system, then I have to figure out how to set up a backup system in case it goes south. With the schematic above (the traditional system), you can flip a switch and voila! You're on a backup electrical system. Simple? No, but as I said, enough people have put this system in that you can just look at where they put what and do the same thing.

Vertical Power has drawn out a schematic for a "get home" system here. As near as I can tell, it takes the main battery power, runs it through a fuseblock, and then out to the Vertical Power unit. And then has several switches to bypass the VP-50 if you need to. Philosophically, I get it. I also get that it adds expense back to a system that I'd hoped the VP-50 would cut. What it looks like behind the panel? I haven't a clue.

It's times like this I really appreciate the homebuilders of yesteryear. They had no Internet to compare their projects with. Of course, they didn't have the electrical systems homebuilt aircraft do today.

Meantime, if you have also purchased a Vertical Power 50 system for an RV-7A and you've designed your electric system and have some pictures of your installation (maybe even a step by step guide), by all means, contact me.

One thing I did accomplish yesterday was finalizing the location of the main instrument on the panel -- the Dynon 100.

This will require moving the left rib closer to the center. I also moved the backup airspeed and altimeter to just left of the Dynon (instead of below it) and moved the TruTrak autopilot selector to below the Dynon. I also eliminated one switch. Now I've got to figure out how to get this into some sort of CAD design to take to place that can cut the panel.

Friday, December 26, 2008

No RV Hotline this week

I'm due to publish the RV Builder's Hotline this weekend. However, there is precious little going on in the RV community, there are no "hot" threads anywhere that I can find, nobody has submitted anything to be published and I'd rather not put out a crappy issue.

Sunday, December 21, 2008

Another crack at the instrument panel.

Weird. I wrote a lengthy treatise on this version and Blogger lost it, oh well. I was going to go out to the hangar today and do as one of you suggested -- sit in the plane with the seats installed, put some pictures on the panel and see how things look. But it was -10 today. So, instead, I noodled on the idea of moving the support rib in order to put the Dynon D100 directly in front of me.

As you can see above, perhaps, I'll move it a bit to the center (that's the direction people move it, right?). I'll order a new rib because the one that's there now is already riveted to the subpanel, and this way I won't have to be terribly precise in cutting it out of there.

I also moved the switches back to above the throttle. And I moved the VP-50 to just above the switches because I think there's a possibility the 7 and 8 switches on the VP-50 might someday be configured to operate a flap motor. I don't believe it can do that at the moment. I also want to find out if the VP-50 panel unit occupies the same cutout size as the VP-100. I want to keep options open for an upgrade down the line.

And I also moved the GRT engine monitor to above the radio stack, and kept some room for a map box on the right side (I couldn't find a map box on the site, however). But I want to think of that some more because additions to the radio stack down the line might require some space there.

One minor thing -- I moved the "cigarette lighter" to the left side. I don't know how the Zaon traffic unit gets its power but it's a portable unit that I'd put on the glareshield just in front of me so maybe it makes some sense to keep a power source close by.


Friday, December 19, 2008

The 'for sale" sign

I've put 7 -- almost 8 -- years of work into the RV-7A project and I intend to continue working on it, but I have to prepare for the obvious -- that I'll have to sell it. The economy is bad -- a dozen folks got gassed at my place today and more are due -- my health and that of my wife have been deteriorating to the point where it's obvious my plans for how we'd spend our senior years are not in sync and not really possible, and the economy has pretty much destroyed our retirement funds and although there's enough time before we retire (I hope) to get them back where they were, there's nowhere near enough time for the fund to get anywhere near our being able to live at the level we'd hoped.

I'd hoped to be able to finance the engine purchase but that hasn't worked out well either and this is not a good time to carry debt.

I've sketched out roughly what I've put into it and that's what I'd likely sell it for -- what I put into it. No profit, no charge for the work and no discount.

Here's what I've put into it:

Tru Trak single axis autopilot = $1,500
Icom A210 Radio - $1,200
Artex 406 mxh ELT - $950
Whelen System 6 Strobe package - $950
GRT EIS - $1500
VP-50 - $1,500
Dynon D100 Super Bright pkg - $2500
Garmin 327 Transponder $2,300
Airflow high-performance boost pump - $415
Equipment Subtotal --> $12,815

Seats (Flightline) $507
Hooker harness w/ crotch strap - $750
Oregon aero cushion core -$580
Interior subtotal -->$1,837

Mattituck IO-360 FP engine (but can be a CS) fuel injected with one Lightspeed ignition - $24,500
Engine subtotal --> $24,500

RV-7A project
On landing gear (nosewheel breakout force has not been set), canopy frame is done and the front fairing completed. Tip-up. Tops skins not riveted on (I need access to the tail). 1,800 hours of work invested so far
Total -->$20,000

I get about $60,000 in my calculation and that's about what I'd sell the project for. No tools are included because I need to hang onto the hope that I can build an RV-12 and do the kind of flying that I'm more likely to be doing -- by myself, in the daytime, in the vicinity of the airport.

Alternatively, I'd consider taking on a partner in the plane, although I have to admit I have no idea how such a partnership works. So you'll have to supply the brains.

If you'd like to take a look at things, I would encourage you to plan to come up to the hangar at South St. Paul (KSGS) and assess it for yourself.

Like I said, I'm not anxious to sell it and cash out, but at the moment I'm willing to and I probably should before I absolutely have to.

Thursday, December 18, 2008

Don't hit the cow

I'd love to tell you that one of the first things they teach us in flight school is "don't hit the cows." But it's not.

(h/t: Michael Wells)

Tuesday, December 16, 2008

Panic attacks

I picked up a bunch of avionics goodies down at SteinAir on Saturday... and I haven't had a good night's sleep since. I've woken up each morning with some sort of "what have I done?" panic attack that a lot of RV airplane builders know well. I had the same feeling back when the fuselage kit was delivered and I took everything out to inventory it. I thought, "there's no way I can do this, there's too many parts." But, some years later, there the airplane sits on its landing gear in a hangar at South St. Paul airport.

I deeply hope the same thing happens here because -- it can now be revealed -- I haven't got a clue what I'm doing here and there aren't that many parts! I've generally come to understand AeroElectric Connection after years of reading it, and I've sketched out a wiring plan of sorts, but this? This is the real thing. There are wires that go from here to there, split to yonder, loop past somewhere, and end up plugged into some other gizmo which, if you do it right, will light up and work. And if you do it wrong, will cost you thousands of dollars.

That's what's waking me up at night. I have no idea where to start, what to do, or what to plug in where.

What you see up above there is the Garmin 327 transponder (which as near as I can tell doesn't come with a harness or any instructions for installation, but I could be wrong), the Dynon 100, which comes with a harness I bought ($90), although I'm not sure what goes where (it does come with a nice installation manual, however.)

There are a few labels at some ends of the wire, but not at the other. (Update: Stein tells me"
The first harness is the Dynon harness as well as the Transponder harness. The connector with the metal cover on it is for the Txpdr. We wired the Txpdr and Dynon together for you to try and simplify things in the future.)

And also above is the Vertical Power 50, which is a nifty little unit that will make my wiring simpler,I'm told. But when I wake up at night, this isn't very simple to me:

I think this is the premade $295 wiring harness, although as you can see, it's not entirely premade. VP, according to the installation manual, requires a special crimping tool for its D-SUB connectors, which -- from what I understand -- are made from the gold plating of Saddam Hussein palaces. You need to buy a special tool ($300) to crimp them or rent one at $10 a month (with a deposit). I was under the impression you didn't have to do that if you bought the wiring harness, but I hadn't finished the load planning worksheet for the plane yet so I don't think Vertical Power had any information on what equipment I'd need to wire. My fault. I think.

I'm sure this is going to be fun. It's the sort of project that just begs for a weekend-long blizzard in Minnesota to force me to tackle.

But first I have to head off to work, where perhaps I can get a good day's sleep.

(BTW, check out Tom Velvick's blog. He has a VP-100 installed and his post on the start-up sequence is really interesting.)

Sunday, December 14, 2008

First crack at the panel

Update - Here's take 2

I've been collecting some of the electronics that I'll be using in my RV-7A over the last few years to try to spread the cost out a bit. But since I'm planning the wiring for the airplane now, I needed to make a few big purchases, which I did yesterday.

When I say "big purchases," I mean big purchases for me. From what I can tell, most RV builders are putting at least $20,000 into their panels. And as Stein Bruch said yesterday, his firm rarely builds a panel for under $80,000.

It's easy to get sucked into the "keeping up with the Joneses" syndrome in this business and it's a good thing, I suppose, that the recession has snapped us -- or at least me -- back to reality. I'm a VFR "go up and look down" kind of pilot and that's about it. Yes, I intend to fly cross country back to New England or down south, but I have no intention of doing it in crappy weather or at night, so I don't really need bells and whistles. Besides, there's nothing that says I can't add equipment later.

So yesterday, I wrote a $6,400 check to Stein and added the Vertical Power 50, the Garmin 327 transponder, and the Dynon D-100 EFIS to the collection of boxes on the shelves here at home. Would I rather have an Advanced Flight System 3500? You bet. But I simply don't have the money for it and I'm not interesting in taking on debt. The next owner of N614EF can do that.

Anyway, I'm trying to mess around with a design for the panel and that's it above. I need comments. I've got the Garmin portable GPS in a little more prominent spot than a lot of people do, but I rely pretty heavily on that, given that I fly under the Twin Cities Class B. Really keeping a close eye on situational awareness with regards to airspace is really important.

I don't have an audio panel. I have a small intercom, so the audio stack (currently just the transponder and the ICOM A-210) is pretty small. I've left room in that general area, however, to add a PS Engineering audio panel at some future point.

Not shown is the ELT switch. I'm not sure where to put that. I also haven't investigated the Lightspeed system that's on the engine yet. I'm using half a system and I'm not sure what has to be on the panel to accomodate that. And I'm leaving room for a map box although I doubt I'll need one.

There are a few switches down there by the VP system. I figure I'll need to gang up a few things (strobe/nav/landing lights) on switches. I could be wrong. But this system eliminates the need for circuit breakers and fuses (mostly), which frees up panel space and also some space behind the panel.

I need your opinion on this initial sketch.

Saturday, December 13, 2008

New Hotline posted

I think I missed a week with the Hotline. I got sick a few weeks ago and missed some work and didn't feel up to working on the Hotline. Then, for the last week, there was about three separate mornings that required 4 a.m. wake-up times, which left little desire for working at night. Plus there just isn't a lot of RV airplane-related news in the dead of winter.

So here it is. It's not the best I could do but it's worth twice the price you paid for it.

Tuesday, December 2, 2008

Why do airplanes crash?

(This is reposted from my day job)


Do planes crash because of the culture of the people flying them? Malcolm Gladwell, whose speech aired today on the first hour of Midday, certainly thinks so. We live, of course, in an area with a lot of airline pilots so I'll defer to them. But I have to think there's going to be a lot of reaction to Gladwell's assertion that airline tragedies have a certain ethnic basis.

During his speech, given at the New Yorker Festival in October , Gladwell referred to a section of his new book, "Outliers: The Story of Success," in which he analyzes airline crashes and determines that pilots from certain cultures tend to crash planes more than others. Some cultures are better at communicating than others.

And he acknowledges that his conclusion is uncomfortable. It's also very debatable.

"Look at where the countries with the safest rate of airline travel are," he says near the end of his address. "The United States, Australia, and the United Kingdom." He reasoned that people in those countries are culturally more inclined to communicate better as a matter of character and personality.

As he said in a CNN interview:

Korean Air had more plane crashes than almost any other airline in the world for a period at the end of the 1990s. When we think of airline crashes, we think, Oh, they must have had old planes. They must have had badly trained pilots. No. What they were struggling with was a cultural legacy, that Korean culture is hierarchical. You are obliged to be deferential toward your elders and superiors in a way that would be unimaginable in the U.S.

Let's ignore for now that one of those Korean Air jets got shot out of the sky. But what Gladwell didn't point out is that English is the official -- mandated -- language of aviation on international flights. When you remove the international flights from the accident database, the gap between the English-as-a-first language countries and those who aren't speaking their native tongue closes. Isn't at least possible that the reason there's a communication problem isn't that there's a cultural problem, it's that there's a lack of mastery on the language being mandated?

Gladwell used an example of this without saying so: The Avianca Flight 52 crash on Long Island. Gladwell relayed the communications in the cockpit and with the controllers for Kennedy Airport, but he never mentioned they were speaking two different languages. The flight crashed because the jet ran out of fuel and the controllers never realized there was an emergency in the first place.

According to a 1990 article in the New York Times:

A captain for Avianca Airlines told Federal investigators today that the company did not train its flight crews to use specific words in asking air traffic controllers for priority treatment when a plane was running out of fuel.

Again, those are international standards that weren't followed, more of a sign of bad training and a bad airline than a bad culture. But it was more than even that, according to the National Transportation Safety Board. The plane crashed because the pilots (a) didn't manage their fuel (b) didn't communicate their situation soon enough (c) failed to follow airline "operational control dispatch system to assist them." And it crashed because the FAA didn't have a standardized understandable terminology for pilots and controllers in the given situation. Also cited was (a) windshear (b) crew fatigue and (c) stress.

In other words, a lot more than culture went into that tragedy.

But one assertion which I'm waiting for the local airline pilot community to confirm -- or deny -- is Gladwell's statement that, "in an emergency, the safest system is one in which the co-pilot does the flying." He suggested that it would be the more experienced flight officer who would be able to decide the best course of action, and monitor the situation, if he wasn't burdened with actually flying.

And it's true that an old axiom in aviation is when there's an emergency, the first thing to do is wind your watch (I told you it was "old"), because that gives you time to think.

But the greatest pilot in the history of aviation may be Al Haynes. He was at the controls of a United DC-10 went it lost all of its hydraulics. It cartwheeled at the Sioux City airport

By all accounts, Haynes, his crew, and all passengers should've died. But 185 survived. Why? Haynes talked to and listened to as many pieces of advice as was available to him. It's something Gladwell touched on too briefly. It's called "cockpit resource management," and it's when the pilot and co-pilot are operating on the same page and the junior officer isn't afraid to question the senior officer's decision. (Aside: There's a pilot in Minneapolis who writes a terrific blog, "Blogging at FL250," who touched on the relationship between flying pilots. It's well worth a read.)

Minnesota's two most recent high-profile plane crashes were both examples of CRM gone bad. In December 1993, 16 passengers and two pilots were killed when a Northwest Airlink plane crashed in Hibbing.

The co-pilot tried to alert the captain about the altitude of the plane while executing a banned maneuver. "The captain's record raised questions about the adequacy of his airmanship and behavior that suggested a lack of crew coordination during flight operations, including intimidation of first officers," the National Transportation Safety Board concluded in its investigation. (Also see a New York Times article on the crash.)

And in 2002, the airplane carrying Sen. Paul Wellstone and members of his family and campaign, crashed in Virginia-Eveleth because, the NTSB said, the pilots had violated several policies and, basically, didn't pay attention to basic airmanship to keep the plane from stalling and crashing.

More often than not, that, and not the culture of a pilot, is why airplane's crash. Pilots make mistakes

(Photo: Getty Images)

Here's a comment an airline pilot posted to the original article.

For what it's worth, I'm an airline pilot, author, and a columnist for I've been interviewed once or twice by MPR.

On the whole I've been very disappointed by Gladwell's comments on air safety.

I do not, as Gladwell apparently does, believe that the ethnicity or cultural background of a cockpit crew has a serious bearing on global air safety in 2008. It's far less of an issue than it once was. Most of the things he talks about have been engineered out of the picture.

But even his dissection of Avianca 52, a crash that occurred almost 20 years ago, is, if anything, only partly right.

Other of his remarks, meanwhile, are outright reckless and untrue.

Gladwell says, for example, "The single most important variable in determining whether a plane crashes is not the plane, it's not the maintenance, it's not the weather, it's the culture the pilot comes from."

That’s totally absurd, and I am extremely disappointed that somebody as influential as Malcolm Gladwell had to say it. In addition to being incorrect, it encourages the widely held notion that non-western airlines are by their nature less safe than those of North America and Europe – a mythology I’ve addressed many times in my own writing.

- Patrick Smith
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