SparrowHawk Build Pictures

[r.coplen]

Repainted Cabin

Repainted Cabin

Repainted the cabin because we had some taped edges that I just didn't like. It's hard to see it in the picture but it is really a nice metal flake fade with three coats of clear coat. I know it will take some work to keep the dust off but it will look nice when shes cleaned up.

 

[barnstorm2]

Well Done!

 

[Gyrobound]

Randy, you changed the look a little from the other painting pictures. Real nice job there. Tail looks sharp too.
Like I said before, if you have others you'd like to share you can send them to my email address. I'd love to see them.
Notice you are sporting a little growth there on the chin and face. Looking good.

Scott

 

[r.coplen]

Starting on Engine

Starting on Engine

Time to unpack the engine. I am taking some parts of the engine for painting and will take about a week to ten days to get that done. The AAI supplied engine is a fuel injected 148 hp EJ-22.

 

[Gyrobound]

OK Randy, so I was wrong about the beard. I could have sworn, without looking back at them, that you didn't have that in the first pictures. My bad.
Is the engine brand new from the factory or rebuilt - reconditioned?

Scott

 

[r.coplen]

Engine

Engine

Scott,

The engines being supplied with the kit are rebuilt to AAI specifications. Each engine is additionally run on AAI,s test stand for at least an hour as an extra quality control process.

 

[Gyrobound]

So they are not new engines or are new engines that are built or rebuilt to AAI specs?
If not new, how many hours do they have on them and where are they coming from?

Scott

 

[r.coplen]

Engines

Engines

Scott,

It is impossible to get a new engine directly from Subaru or a Subaru dealer to use in aviation. There are ways to score a new block but you can't get the wiring harneses without starting to get people asking what you are doing. We order at least 30 engines at a time so there is no way to keep under the radar at those quantities. The thousands of EJ-22s and EJ-25s that are used in the kit built aircraft are almost all rebuilt automotive engines. The only exception I know to this is NSI who does buy or makes almost all new parts. They do not buy from Subaru. Their full power system is about $18,000 and we would still have to add $1000s more for additional engineering costs to adapt that engine to the SparrowHawk. I am not representing AAI corporate in these figures but just giving you my best guess. If you went to that engine it might add an addition $16,000 to $20,000. It is a far out power plant. Nothing like I,ve ever seen before. But back to reasonable kit prices. I think AAI is doing everything they can to make sure the rebuilt engines are the best possible. They are certainly doing as much or more than other kit manufactures the supply the EJ-22 with their kits. I have know way of knowing the hours on the rebuilt engines. What I think is important is the engine is totally rebuilt. The cam shafts are specially designed and manufactured for our engine. They use all new bearings, rings, water and oil pump, cylendars honed, and a lot of other stuff I not privy to. Each engine is mounted, proped and fully tested before shipping to the customer.

I am going to paint my whole engine black with some gold highlights and to do that I have had to tear it apart to dip the parts before painting. All the parts inside look brand new. The valves look new, the valve seats are perfect, the engine is clean like a new engine. When I get done with the outside of mine it will look a lot better than new.

Hope that helps, Randy

 

[KenSandyEggo]

https://members.aol.com/CCRInc/RebuiltSubaruEngines.html

CCR at the above link does the engines for AAI. They have an excellent reputation on all the Soob boards that I check out once in awhile.

 

[GyroRon]

As a side note, I got to see Jim Mayfield do a lot of flying in his Sparrowhawk at Bensen Days. It seemed to perform well. I do want to comment that the exhaust note was a good bit louder than the RAF exhaust note on Duannes machine. the supertrapps look good and are lightweight, but they don't do much for quieting the sound. I wonder if any R&D has gone into looking at a quieter exhaust system?

Jake Jacobs had the quietest exhaust I have ever heard on a EJ-22 powered gyro. It was a old propane or refridgerant tank with two inlets and one outlet. Don't know what was inside for baffles.

 

[PW_Plack]

Wow, Randy...

You need to get some professional portraits of that machine when it's finished, and before it gets bugs splattered on it! N17SH will end up being as effective a promotion for your build center as it is for the SparrowHawk.

You need to park it at a custom car show someday, and just watch the reaction. Imagine if these guys who spend big bucks building cars got hooked on gyros!

 

[r.coplen]

Paul,

Thanks for the input. Car shows?!! How bout motorcycle shows?

Ron,

It's not much use to make the exhaust quieter when the prop makes just as much noise or more noise than the engine. One of the goals with the Suppertraps was to make the sound a a lower tone which is much more pleasent to most folks then the high pitch the EJ-22 usually makes.

I know in the future AAI will take a hard look at sustantially reducing the noise of the SparrowHawk.

Thankyou for the imput, Randy

 

[KenSandyEggo]

Ron, I too agree that it's the prop that is the main factor in the noise level. No one noticed when I went from the RAF muffler to the 2-Trapp setup (which I initially designed and had the manifolds fabricated for ), but everyone at the airport was asking me what I did to my exhaust system to quiet her down after I installed my Prince prop.

As a side note, I must have 300 hours on that exhaust setup without a whiff of a problem or ever having done anything to them except for preflighting and removing the packing when I soon found out that it will cinder up and fall to the disks if you have them mounted vertically.

 

[John Conte]

Why Soobs so common?

Why Soobs so common?

I know I'm not on the engine thread, but while we're talking about noise, engines, etc, why does AAI or RAF and maybe eventually sportcopter prefer these engines over a Rotax? Price?

 

[r.coplen]

John,

I am not real familiar with the specifications on the Rotax. I don't have enough knowledge to compair the two. When Jim gets back after Sun & Fun ends I will ask him if others don't give us the answers.

 

[PW_Plack]

John,

I can't speak for everyone, but I'll tell you what I've gathered. The rest of you guys, these numbers are off the top of my head, and if I have any of them wrong, please chime in.

The horizontally-opposed four-cylinder configuration is popular because it (a) results in a compact setup under a cowl, with the cylinder barrels laid out in an optimum position for air cooling, and (b) it has inherently lower vibration than a four-cylinder in-line engine. This is why most aircraft engines are made this way, and why the old VW Beetle and Corvair engines have been popular conversions for aircraft use.

When you move into the water-cooled world, some of the aerodynamic advantage of the horizontally-opposed configuration becomes moot, but it's still a good setup for compactness and keeps the weight concentrated near the center of gravity.

Of all the car engines, Subarus are relatively light for their power, and seem to be one of the few designs which will tolerate being run near their maximum horsepower output continuously. Given enough radiator capacity and a good oil cooler, they appear to be capable of 1500 hours or more without an overhaul if maintained well and not otherwise abused. Most car engines die young if run this hard.

A Subaru 2.2 weighs about 280 pounds, more than some complete gyros, and makes 130 HP with the stock fuel injection, less with a carb. Pulled out of a car, cleaned up and equipped with a reduction drive, they can cost as little as $2,000. You'd end up with a very heavy single-place machine if you took this route. The Rotax 582 makes half the horsepower, at about one-third the weight, but costs about $6000 with reduction drive, and burns about 40 per cent more fuel. Bottom line: Guys trying to build gyros cheaply are about the only ones using a Subaru on a single place.

There are still some gyros around flying with the old Subaru 1.8-liter engines, the EA-81 (pushrod) or EA-82 (overhead cam.) They are limited in how much power you can make through tuning improvements, and are gradually falling out of favor. They typically made 75 to 100 HP, and weighed about 200 pounds. The aftermarket Australian Sub-4 heads provided better flow, and they rated the 1.8L engine with their heads at 125 HP, if I recall.

 

[KenSandyEggo]

The 4 stroke turbo Rotax that puts out 115 h.p. is $21,218. Isn't the turbo limited to a certain amount of take-off time, or does it run continuously? I don't really know. That's a lot of $$$ for 115 h.p., which is probably marginal for the lead-sleds. The non-turbo that puts out 100 h.p. is $12,995. So that's over $8,000 for 15 more horses. The Subarus look better and better.

 

[GyroRon]

Paul, A Redrive for a subaru will set you back over 2000$ by itself. By the time you buy - not build or make yourself - all the parts needed to get a EJ-22 together your not too far money wise behind the Rotax 582. Of course you will have lot's more power though.

Also a EJ-22 will end up buring fuel at nearly the same rate as a Rotax 582, certainly not 40 percent less. I have run both engines myself and the EJ-22 is not that easy on the fuel burn!!!

And last, I think the best arrangement for aircooling a engine would not be a flat 4 arrangement, but a Radial arrangement instead. But a good set of baffles can make the Flat 4 set up run cool.

 

[PW_Plack]

Ron,

Yep - That's why I suggested the price of running a Soob might start at $2000...free engine, $2000 redrive. On the fuel economy, I think Gary Kaminski told me his RAF burns right at 5 GPH at cruise with a mostly stock 2.2 EFI. Rotax quotes the 582 at 7.2 GPH.

You're probably right about the radial and cooling, but I'm not sure you'd get even cooling among cylinders on a pusher.

Hey - I just got the AOPA e-mail bulletin, and it looks like there's another interesting choice - turbine! ATP, Affordable Turbine Power, will have its new engine available for experimentals at Oshkosh this summer. 200 pounds...200 HP!

Affordable Turbine Power Model 6.5

I'm betting "affordable" will be a relative term, and this thing will be pretty thirsty compared to any piston engine, but imagine pulling your gyro up the the JetA pumps at the FBO!

 

[PW_Plack]

Ken,

Right you are. 115 HP for a maximum of 5 minutes during takeoff, 100 HP continuous. The turbo is apparently intended mainly to preserve performance at altitude.

Well, John, you have lots to chew on now, huh! Aren't you glad you asked?