Extreme Windshield

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SheepdogRD
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Extreme Windshield

Post by SheepdogRD »

I figured that a longer, wider windshield would give us improved visibility, particularly over the nose on approach, and out the sides when taxiing and landing. If the windshield went all the way forward to the firewall, a flatter windshield angle might even have a positive aerodynamic effect.

So, about four years ago, I started trying to build a larger windshield. Early attempts just didn't work. I discovered that Lexan is wonderful stuff to work with, and it's pretty forgiving. But it wants to stay flat, so we have to engineer it to the shape we want. There were lots of starts and stops, and an unenviable string of attempts that ended in "Well, that didn't work." But each attempt got me closer.

Not long after I started the project, I met Barkley Smith of AeroSmith Composites. AeroSmith manufactures the fiberglass parts found on Just Aircraft. Barkley is both artist and craftsman, and he's fun to work with. If I toss out an idea, he tosses it back improved in some way. He wanted a bigger windshield, too, so we've worked on this together.

We've taken the windshield to the limits of the space available. Here’s the Extreme Windshield, installed on N570L:

01 Windshield in Place.jpg
02 Windshield from the Side.jpg

This windshield provides better visibility overall and a more spacious feel to the cockpit. It extends from the headrack all the way forward to the firewall, and clear across the full width of the cockpit. It The new boot cowl is very short across the front, and the sides are only as high the tabs on the fuselage rails.

If you choose to minimize the height of your panel, or angle the panel sides down (Steve Henry did both on YeeHaw 7), or if you reduce the panel width, this windshield provides a great view out.

The panel on N570L is less than 19" wide; it leaves almost 7" open on each side, and I can see clear to the firewall on the opposite side of the cockpit just by turning my head. Smaller side gaps still provide much better vision out. With Lexan cowl side panels and a narrowed instrument panel, the view is amazing...

05 Windshield from the Pilot Seat.jpg

... and it will get better. The sides of the boot cowl in the picture are about 2-1/2" high. They'll be cut shorter -- to less than 2" -- when the installation is complete.

A much larger panel cover is required -- about 21" x 36". But the cover lines up well with the eye, so we'll be looking over it out the windshield, and under it out the side panels. The one on N570L will be .040" Kydex.

The windshield is .090” Lexan sheet that comes with the Just kit. The current system uses the 914-style cowling, meaning it should fit new installations of Rotax, Titan and Yamaha engines, and may fit other planes using the 914-style cowling. We’ll be trying other engine installations.

It may be possible to retrofit the windshield to some existing 914 cowling installations, but we haven’t done that yet. It might even be possible to retrofit 912 cowling installations, but we haven't tried that, either. We'll try.

Installing the Extreme windshield is different from installing the standard cowlings. The windshield and boot cowl are installed first, and then the upper and lower cowling pieces are installed to fit with the boot cowl.

The key to installing this windshield is a fiberglass former seen in the picture above and the one below (although the former appears to slant forward in the picture below, it's actually upright). The former, which is riveted to the firewall, makes it possible to bend the Lexan to the shape we need at the front corners. The installed windshield is sandwiched between the former and the boot cowl.

03 Windshield Former.jpg

A Work in Progress

We haven't flown this yet, but test flights are on the way.

There's one issue we're still resolving -- fitting the upper cowling to the boot cowl. Here's the issue: various engine and prop spacer installations require different length cowlings. But the Just cowling system is tapered. It gets wider as it goes back from the nose. Measured 7 inches back, where the sides get relatively straight, it’s about 25” wide. At the back end, some 33” from the nose, it’s about 33” wide. The firewall is only 31-1/2” wide. That means there’s only one position where the cowling fits ideally, and any other position requires the builder to bend the cowling system to fit. The cowling can flex a little, so there is a range of acceptable nose lengths.

Most 912 installations on the bed mount use the "912" cowling because it fits better on shorter engine installations. The "914" cowling is the better choice for “ring” mount installations, where the engine is 3” further forward. The 914 cowling is the basis for development of most other cowlings -- Titan, ULPower, etc. We’ve also made it the basis for a new lower cowling that has an opening for the radiator, similar (in size, anyway) to the one in the 912 cowling. It should fit almost all 912 and 914 installations, including those that previously would have used the 912 cowling.

The Titan upper cowling has relatively straight sides because of the cowl cheeks, so it should work well. It looks like Steve's Yamaha installation is right about where my Rotax is, so it should fit without a lot of grunting, too; we’re in that “sweet spot” of cowling length. But other installations, such as 912 engines on the bed mount, are shorter, and that would make the existing 914 upper cowling too narrow because it sits further back.

We've designed a new upper cowling that fits this windshield no matter how long the engine/prop installation may be. It's ready to prototype; if it works as expected, it'll make installation a whole lot easier. To test, we'll install it on my 912 big bore on the "ring" mount, and on Barkley's 912 on the bed mount. I'll post on that when we have results.

There’s more to come...
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Richard Holtz
Highlander N570L -- Ms. Tonka -- in gestation

If just enough is really good, then too much ought to be perfect.
Clark in AZ
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Re: Extreme Windshield

Post by Clark in AZ »

Very nice! Looks fantastic, I wish you well in your tests.

Clark
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LAS
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Re: Extreme Windshield

Post by LAS »

Best of luck! I’ll be watching closely.
AV8R Paul
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Re: Extreme Windshield

Post by AV8R Paul »

That is looking great.
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SheepdogRD
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Re: Extreme Windshield

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Here are shots of Steve Henry's Yeehaw 6 (with the standard windshield) and Yeehaw 7 (with the Extreme windshield). They're not quite at the same angle, but they're pretty close, and you can get an idea how the view out is improved.
Comparison 2 - Original.jpg
Comparison 2a - Extreme.jpg
If you're planning a full-width panel that's relatively high, the Extreme windshield probably isn't going to help much. But, if you can keep your panel low, or if you can lower the sides -- or both, like Steve did in Yeehaw 7 -- you can get improved visibility:
Panel - N642SC.JPG
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Richard Holtz
Highlander N570L -- Ms. Tonka -- in gestation

If just enough is really good, then too much ought to be perfect.
Clark in AZ
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Re: Extreme Windshield

Post by Clark in AZ »

So, where is this extreme windshield in terms of release for sale? Are they shipping yet?

How much fabrication is involved compared to the Steve Dentz molded windshield? I have a SD molded acrylic windshield that I have not installed yet, and am thinking of getting the extreme instead. Is it easier to install the upper cowling? Any input would be appreciated.

Clark
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SheepdogRD
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Re: Extreme Windshield

Post by SheepdogRD »

We're shipping the systems now.

Builders who already have a standard 914 upper cowling may be able to use it; it worked for Steve Henry on Yeehaw 7. But, because the standard 914 cowling widens as it goes back, builders with other longer engine installations may find that it simply doesn't fit well at the firewall. They can do a little fiberglass work on it, or use the modified "straight-back" upper cowling that has a constant firewall-width fit along much of the aft end. For new installations, especially for builders who don't have a cowling yet, that's what we'd recommend.

Builders who have standard 912 cowlings may be able to use them with the Extreme windshield, but it depends on the length of the engine installation.

Bedmount installations (most 912 installations) have an additional option: they can use the "straight-back" upper cowling with our "913" lower cowling that fits both longer and shorter engine installations (and has a scoop for the radiator). That system should also fit planes with a nosewheel. A picture of it is below.

I wouldn’t suggest that installation is any easier or harder than the standard acrylic windshield. It’s different. There's no fabrication necessary with either one, but both require a lot of fitting, trimming, and attention to detail. Installing the acrylic (Plexiglas) windshield requires special drills, and more attention to technique because the material can crack if it's overstressed. Proper edge finishing helps eliminate that problem.

The standard windshield is installed after the cowling and boot cowl have been fitted. You fasten the rough-shaped Lexan (or preformed Plexiglas) windshield to the windshield bracket. Then you push it forward and fasten it to the boot cowl, and then you install the channels on the back. That's a radically condensed version of the job, because there's a lot of fitting and trimming to be done as the process goes along. Once the system is fitted, you take everything apart, do your finishing operations, and reassemble for final fastening.

The Extreme windshield is installed before fitting the cowling parts. First you fit the windshield former to the firewall and fuselage top rails, and cut the firewall to a corresponding shape. You fasten the rough-shaped Lexan windshield to the windshield bracket, with the front of it laying on top of the former. After some trimming, you bend and fasten it to the former, the side tabs, and the back tabs. Then you fit the boot cowl in conjunction with the upper and lower cowling parts, fasten it in place, and install the channels on the back. Again, this is a radically condensed version of the process, because there's a lot of fitting and trimming to be done. Once the system is fitted, you take everything apart, do your finishing operations, and reassemble for final fastening.

There are many similarities between the systems, but there are some major differences.

The Extreme windshield installation isn't covered in the Builder's Manual, so the kit comes with Lexan-cutting patterns and step-by-step instructions for both Lexan and acrylic windshields.
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CanadianSheepHunter
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Re: Extreme Windshield

Post by CanadianSheepHunter »

I just came across this, I'm building a SS and probably using the Rotax Edge 156 HP like Dean in Texas did. I currently have the 912 Cowling and boot cowl that i will have to return. I really like this and want to use a narrow dash like in the pics. I'll let the order desk know I'm interested for sure!

Is this available from the factory?...or just from you?

I already have my kit... I bought a kit that a guy built on for 100 hrs aprox. You can private message me on here with price etc, or on here, I can give you my personal email on private message.
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SheepdogRD
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Re: Extreme Windshield

Post by SheepdogRD »

If you have a kit on order, you (or your dealer) can call and add the Extreme windshield installation kit to your order. You can also change to the Extreme windshield boot cowl at no charge. If you want to change to the "913" lower cowling and the "straight-back" Extreme upper cowling, those changes can be made at no additional cost. We'll deliver the relevant parts to the factory for shipment with your kit.

Right now, the acrylic version of the Extreme windshield is only available from me. We think we can ship the acrylic windshield with your order, provided there is room in the crate.

If you already have your kit, we can arrange shipping.
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SheepdogRD
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Re: Extreme Windshield

Post by SheepdogRD »

I've moved all of the windshield installation pictures to a separate thread here, called Extreme Windshield Installation. I'll keep this thread for features, developments, questions, answers, and general information about the Extreme windshield system.
Richard Holtz
Highlander N570L -- Ms. Tonka -- in gestation

If just enough is really good, then too much ought to be perfect.
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SheepdogRD
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Re: Extreme Windshield

Post by SheepdogRD »

Here's a fine example of an installed Extreme windshield: Dennis and Linda Rowe's Yamaha-powered Highlander.
Rowe 1.jpg
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Richard Holtz
Highlander N570L -- Ms. Tonka -- in gestation

If just enough is really good, then too much ought to be perfect.
Clark in AZ
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Re: Extreme Windshield

Post by Clark in AZ »

Nice! Great photo too!
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SheepdogRD
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Re: Extreme Windshield

Post by SheepdogRD »

Q: Do I need a different boot cowl to use the Extreme windshield?

A: Yes. The Extreme windshield is much larger -- both longer and wider. It extends from the headrack to the firewall, and completely from side to side. The Extreme boot cowl is tiny compared to the standard one, and its sides can be trimmed even further.

Here are some comparisons of the untrimmed boot cowls before installation:
Boot Cowl Comparison 1.jpg
Most of the front section on both of these cowlings is trimmed away, leaving a short ledge where the upper cowling is fastened.
Boot Cowl Comparison 2b.jpg
Now let's put the Extreme boot cowl on top of the standard boot cowl and see how much more open that area can be:
Boot Cowl Comparison 3.jpg
As delivered, the Extreme boot cowl sides are tall, so you can adjust the way it fits. Once you have it the way you want it, you can cut away so much of it that it nearly disappears, as on Shawn Taplin's SuperSTOL:
Taplin Install 5s.jpg
N331AK-07.jpg
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Richard Holtz
Highlander N570L -- Ms. Tonka -- in gestation

If just enough is really good, then too much ought to be perfect.
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Extreme Windshield with 912 cowling

Post by SheepdogRD »

Good News! Here's an in-process look at the Extreme windshield retrofit to a Highlander with the 912 cowling.

The boot cowl will be painted satin black to match the top of the upper cowling.
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SheepdogRD
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Re: Extreme Windshield

Post by SheepdogRD »

Here's another look at Jody's 912 cowling installation:
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