Subaru & Sparrowhawk Questions

[mbell]

A newbie here. I have been researching the Sparrowhawk to purchase. I have read every Sparrowhawk thread here, plus looked at the company and dealer websites. I got an insurance quote so I know it's really insurable. I was very skeptical about the engine, but now I pretty much buy into the idea that it's OK to run it at higher RPMs than it would see in everyday car cruising, and it's probably OK to trust the ECM without a backup. But I'm a little surprised that the stock setup from GBA does not include dual ignition. And I'm more surprised that it doesn't include a dual electrical system. The Eggenfellner Subarus (http://www.eggenfellneraircraft.com/electrical.htm ) used in RVs and other homebuilts have dual batteries and (I think) a system that automatically kicks in the backup system if the primary fails. Since it's not that unusual to have a failure that would shut down the electrical system or require that it be shut down, this seems like a good idea. His website shows how it's setup and wired. I think the fuel pumps can be set up so that if the pressure drops the second pump comes on automatically too but I can't remember where I saw that. I see where a nearly-dual ignition is available and some of you use it. I haven't seen anything about dual electricals. Does the Sparrowhawk setup use CDI or something that doesn't depend on the electrical system 100%? Much ado about nothing? Thanks,
Mike Bell
Elk Grove, CA

[Heather Poe]

Fuel pump switch over:
http://www.rotaryforum.com/forum/showthread.php?t=9442

[PW_Plack]

Mike, modern car ignition systems probably fail less often than the old dual magneto systems on certificated aircraft engines. Machining a second plug hole into a EJ-series head may create a less reliable engine overall.

If you lose an alternator, and have even the car's idiot light circuit hooked up, you'll be alerted in plenty of time to land safely. If you have an ammeter and check it during run-up, you should see a strong charge indication right after starting. Even if all you have is a voltmeter, the least useful electrical indicator, you should be able to watch it rise from the 11's to a little over over 14V in the few minutes after starting.

[StanFoster]

Mike: I can personally voutch for having a nice back up fuel pump system. Thanks to Heather sending me a diagram one day...this brought my back of my mind thought to reality. I diverted somewhat and wired it differently as both of my pumps are completelly isolated. I have a very reliable backup that is very easy to check and even overide in flight.

I have to second the fact that the odds of the Subaru ignition failing are very slim.

Whats nice about gyrocopters are that if you fly smart....an engine out is nothing but a nuisance. I have had a bunch of them in my two stroke flying days....and each one while exciting at the time ended up no damage and just a nuisance getting the gyro out.

The Subarus I have been flying in my RAF and now my SparrowHawk are very reliable...but they could quit the next flight.


Stan

[GyroRon]

Mike, apparently you didn't notice that the engines provided with Sparrowhawks are not new engines, not remanufactored engines, and not rebuilt engines.... No they are simply used engines from a junk yard - well they would never call it a junk yard, they would call it a automotive recycler or something else along those lines.

Bottom line is don't fly over stuff you don't want to or can't land on

[Timchick]

Stan,
You should probably point out that your previous engine outs were not in your Sparrowhawk.

[brett s]

I've never had an ignition failure in a car & I've been driving for almost 30 years - but I've have several ignition failures in certified aircraft engines using magnetos (point failures usually) in only about 500 hours of piston engine time. I know which I'd prefer to fly behind...

The only reason aircraft have dual ignition systems is because the old stuff was so unreliable.

[Chuck Roberg]

Mike like Paul stated. If you lose an alternator in a Sparrow Hawk. There is a large red light in the upper left corner of the instrument pod that will come on warning you of a problem.

A quick scan of the LCD display would show the current voltage. If it low then then you know the problem is electrical. Best to find a good place to land before the voltage drops below 9 volts. Thats about the voltage level when the ignition system will drop out. Thats a bad thing.

The red light is to alert you that one of the presets, for one of the functions, that the LCD display shows is out of range. Either too high or too low. You have to check the display to determine which it is.

[StanFoster]

Ron: As far as calling them "junkyard engines" I have flown 235 hours without so much as a hiccup in my junkyard powered RAF....and have 135 hours in my junkyard powered Sparrowhawk without a hiccup. By the way...these engines are thoroughly inspected....compression checked...run...and many other tests before they are sent out. They are the best engines I have ever been pushed around with. There is the option of buying a rebuilt engine for another $2700.00 I personally think thats stupid as the chances that the engine I receive will get a lot of use out of it...and then I can always go to the junkyard with just a part of that $2700 and have another engine in it.

Compare that with 18 engine outs in my two strokes....taught me not to trust engines period.;)


Stan

[GyroRon]

Stan, I got no problems with them being junkyard engines.... Just that with the nature of the questions the person who started the thread asked, he might be surprised to know that these engines are not new nor overhauled.

The Eggenfellner Subarus ARE overhauled and modified heavily. Big difference between the two complete packages.

For a gyro I suppose I would prefer to save money and go the typical gyro subaru route over the very expensive Eggenfellner route.

[StanFoster]

Ron: I wish that RAF and SparrowHawk supplied their kits with NEW engines...of course thats a no brainer.

I think for the amount of money the kits sell for..many new buyers would expect a new engine. I know it wont ever happen...so this is the next best.:)

However...one of the single biggest surpises to me when I started in these two place gyros was how commonplace it was to just go down to the junkyard and pick you out another motor...then go switch it out in a couple of days and not have a lot of money in it.


Stan

[mbell]

Thanks to all for your replies. Ron, I did notice right away that rebuilt engines were an option. The discussion here about Japanese taxes/junking almost-new cars was enlightening. I would opt for a rebuilt so I would have more confidence in what's inside, but I can see why others might prefer an engine that had never been opened and messed with. The dual pumps with auto-switching setup seems a no-brainer. Two independent electrical busses (at least for the engine) seems smart to me. Gives you an option if the battery fails or something electrical's burning or smells like it's about to burn.

Brett, I've never had an ignition failure in a modern car, but my wife's Chrysler has died more than once when the computer (?) didn't like the voltage from a bad battery or the phase of the moon. As Eggenfellner points out there are lots of single-point failures waiting to happen on certified engines too, so nothing's perfect. The radial I'm currently flying behind has a single drive for the oil and fuel pumps. If that goes, all the manual fuel pumping on earth won't keep it running very long. My hangar partner's "reliable" Pratt & Whitney failed on us over South Dakota enroute to OSH from a bad cam drive gear. One of the appealing things about gyros to me is (as Stan said) a deadstick landing is usually less of an event than in a fixed-wing since you can land so slowly. I guess we all want to stack the deck in our favor as much as is reasonable, and then it's just a question of what's reasonable.

Mike

[dragonflyerthom]

Very insightful Mike.

One of the great kept secrets from the General Aviation community is the Experimental catagory. We can do things GA won't allow. You can play by your rules, make changes that you think are better and fly with an enjoyment like no other. Keep up the research.

Welcome to one of the best reference areas in aviation. Some good thinkers and plinkers here.

[Steve McGowan]

Ima gonna put a Mazda ROTARYon my SH..

What Ya think guy's.. The Black won't like it at all..

[animal]

The radial I'm currently flying behind has a single drive for the oil and fuel pumps. If that goes, all the manual fuel pumping on earth won't keep it running very long. My hangar partner's "reliable" Pratt & Whitney failed on us over South Dakota enroute to OSH from a bad cam drive gear.
Mike
Hi Welcome to the Forum Mike, just wondering what you are flying now?
don't ya just love the sound of those big ole radials.

[animal]

Ima gonna put a Mazda ROTARYon my SH..

What Ya think guy's.. The Black won't like it at all..

steve, just wondering how many hour do you have on the Engine in the Black,I know you have been flying that gyro for years and it looks like it has been giveing you great service. with the power that you can get out of a mazda,that would probably be a sweet setup on a SH. one thing that kind of nags me in the back of my mind is that the crank shafts in subaru's are known to break. Gary Neal I think has had 3 or 4 break and he always has me fly on the edge of open fields when we fly. what kind of Problem have you had or heard about with the Mazda Rotary?
I am really kind of Suprised we don't see More Rotarys on Gyros.

[Steve McGowan]

Tim,,

as of now I have had about 6 engines on the Black.. varying from 30 -700 hrs. the airframe hobbs has 1850+ and Jim Mayfield's "Great White Trainer" had better than 3k on his I believe before he sold it.

Oil pressure and water temp are the main concerns.. and luckily the one I have now is holding up .. I'm also holding my breath and saying that quietly.

The crank breaking on the sub's are due to side load.. the cranks are not made for that..or any side load belt drive engine for that matter .

Inline drive is why the mazda is holding up so well..atleast on the drive it is. My drive is a ROSS 2.85.1 and Mr Sid Ross died a few years ago. His son didn't follow along with his dads work, so everything with that has disappeared ya might say.

When the engine heats up the drives will tighten up due to temperature on the aluminum parts. (over time)The belts will break the crank at the last jernal if it's too tight.

The Mazda on the other hand is a very thirsty engine, 8-9 gph. The RX-7 cars have a 26 gal gas tank.. NOT very fuel efficient..
Very good on the gyro getting your butt out of a problem when ya need the push. But that isa two sided sword.

The EGT on a Rotary can reach 1900:flame:

19000 RPM has been reached on many sprint cars..

A Rotary will be on the Hawk one day... You can bet on it..it's just so much easier..and seems to be quietier too.

steve

[Mayfield]

I had about 3000 hours on my monster before I sold it.

The first engine went 2400 hours and then the tip seals went out.

I used a Ross 2.85 to 1 gear box. I believe mine lasted so long because I propped it to about 5800 max engine RPM and did not spend much time there. I also used pre-mix and disabled the oil injection system.

It would be well worth it for GBA to explore using an RX-8 engine. It's hard to predict whether it would be the "right" engine for the airframe, but it is certainly worth looking at.

Jim

[mbell]

Tim,

Right now I'm flying a Russian Yak-52. 360 HP M-14P, sounds very sweet indeed, but at 15 GPH. I have owned 2 other former Soviet aircraft and they are great machines. It's my 22nd project, all antiques, classics, warbirds and homebuilts. Now that it's done and for sale I'm looking for something different, like maybe a gyro.

Mike