I think for Mr. Ogawa to lsiten we have all should write to OS as a special request for new product development ad send some advance payment to them.

I have reservations about using supretigres again, mainly due to the fact that they lack that italiano attention to detail.

Bob, I did at one stage use a SC (supercustom) 91 in my GP giles 202, and it was a real powerhouse.

Still going 4 years on.

I would love to see an Irvine 90 or at least their 1.20 back on production... they go form the .72 to a 1.50 with nothing in between [:@][:@][:'(]

I wrote to OS , and they say that we have to see the market for production of this engine.

I think that YS could make a few changes to their helicopter engines and that way they could be used for airplanes too. Is more easy that YS do that modification rather than OS develop a new HANNO 90 size engine.

Does somebody have contact with Mr. Yammada for this sugeretion?

I highly doubt YS would ever do that.

Why would they produce an engine that would be in direct competition with another engine they produce.

Sorry guys... It's just not gonna happen.

I was looking at the OS ducted fan engine. It's r.e. and rear intake also.
I'm sure it's designed for high RPM low torque and is not what we want.
Is there really that much demand for a ducted fan anymore?
Are we that outnumbered?

Eddie

Yeah, I think so, Eddie. Someone speculated once, not too long ago, that ALL "competition" engine purchases represented only 8-10% of the engines sold, and pattern was 2% (TWO) percent of the people buying high-performance motors.

Kinda like How come OS won't change the OS 1.60?
*** Because they are selling BUCKET loads of 'em as they're made.... why change?

Plus - sometime ago, I had heard that the highest level of ownership of OS was the SAME as YS....if true (and I have to state that the information I gained at that time was pure speculative rumor), it would CERTAINLY explain why they seem hesitant to make a lot of changes....

They have too many field development product testers/developers in the YS camp....why change that?

Jeff - I know you're just picking - BUT Why not, I've witnessed it. I'm flying a YS110 on my ExplorerV90 turning a 15X10 on 30% all synthetic fuel around 8900 -9100RPM. My Mentor is running the OS91FX turning a 15.5X12 4blade prop with the same fuel around 7800-8000RPM on his Express 2-M . My YS can't turn a 15.5X12 4 blade prop. He gave me a 14.5X11 4blade prop and I'm gonna have to shorten it some to turn it. He has OOS vertical and no power issues with the FAI prelim or final sequence

I hate to see people saying they're running a 13X8 at 11,000+ and looking for more power. They just don't know where the available power curve is for this motor(os). Of course they've not done all the testing to "find" all the power either. He has. Been running that motor in his 2meter FAI & 3-D planes for at least 4 years(maybe more but I don't want to say something I'm not sure of)

If anyone saw the article in 3-Dflyer magazine about George Hicks, he had a picture of Nat with his 2meter 3-D Express powered by the OS91FX. I don't think George would've ignored an underpowered situation. He sure didn't have any power issues when he flew it.


Eddie

Thanks for the kind comments, but that racing part is not true. In fact, the vast majority of the Jett engines are designed for sport, scale, and aerobatics applications. The only two engines for racing these days are the QM40 and QJ-40.

Dub does configure some of the engines for speed applications. You will read a great deal about whiplash and diamond dust speed planes. The key here is that all of the engines are build and configured to order, based on the application for which they are intended.

Over the past couple of years, Dub has developed the big-block BSE engines into amazing powerplants.

Although Dub does make an awesome "90" engine, the SJ-90L and BSE-90L, the Jett BSE-100 and BSE-120 were designed from the ground-up for pattern/3D/scale applications. They turn larger props at lower rpm. All 3 engine are "60" size cases, and they match the mounting dimensions of the OS91FX. Any of the Jett engines are available in either side or rear exhaust configuration. The BSE-120 FIRE version, engine only and spinner nut, weighs about 21oz.

The engines typically are set up to turn in the 9000-11000 rpm range, but when set with a longer pipe, they gladly turn down in the 8500-9500 range.

The engines are not pumped, as with the OS91 or ST90.

As a pattern flyer from some time ago (1980s, early 90s), I sure wish I had one of these back when I was flying I had a sweet flying EU-1A that would have really enjoyed having a 90L in the nose.

I hope this is useful, and provides another "90" size option to consider. Any questions, feel free to email or PM.
Bob

Jett does make some nice looking engines, however, the prices always chase me away.

I will grant you they are not inexpensive. Definately not along the lines of chinese built products. More along the lines of the top end Japaneese and European built pattern engines of a few years ago though.

Looking back a bit, I seem to recall paying somewhere along the lines of $220 - $325 for OS61P, YS61, and Hanno 61 engines 12-18 years ago. I believe the YS120 was more. I would imagine most folks considered those rather expensive. I know I did! They were a far cry from the $99 webra speed .61 I first started pattern with Along those lines, the Jett engines are not too far out of line.

Consider this though, they are made in Texas, USA, made from domestic materials, real chrome sleeve, one of the best carbs anywhere, each one is test run and set up before you get it, and are supported with customer service directly from the man who designed, fabricated and built the engine. As I tell some folks, there is a lot more to the value of a product than its price

Anyway... hopefully they provide for some options.

I was not referring to their value, rather to the consideration that I might screw one up or demolish it past recognition. If I have something too nice or worth too much, I may be afraid to fly it. What kind of phobia is that??

Hi Bob,
Wow, thanks for the information. I'm gonna have to try a Jett 1.20 FIRE. I'd still like to put a pump on it (like a Perry/Varsane) so I could mount the tank on the CG. Any problems that you know of with that set-up? Also, who makes the headers - they look very nice. A Jett 1.20 really weighs the same as an OS .91FX ??
As for price - you get what you pay for. Numbers - based on the serial numbers on the Hanno SPecial. I don't think OS made more than 10,000 of them (actually, I think they made about 7,000 of the original version and maybe 2,000 of the MKII). By the time the MKII came out, the YS 1.20 was dominating pattern. The MKII was supposed to be the penultimate .60. Anybody out there ever run one - please comment. Conversely, in 1997 (give or take a year) Great planes sold 40,000 OS .46FX engines in North America - That's ONE year. The OS 1.40RX is still a great pattern engine and I'm sure OS doesn't see a need YET to produce a more powerful, pattern specific engine.
DOes Jett have a web site??
Happy flying!!

http://www.jettengineering.com/

ini

I have the phobia too Wife, kid, no time, limited budget..... So I do understand! However, even putting a pylon plane in the ground at 150 mph, I have yet to tear up an engine quite that badly. About the only thing you can do to ruin it is consistantly run it lean.

flywilly,

jettengineering.com is the web site. The BSE engines page has most of the 1.20L info on it.

Headers.... I believe Johnson is making those for Dub. They are available in a few different rise sizes.

Pumps...... Dub has in the past utilized the perry pumps in a few applications. I've tried them too. In most cases, they work ok. In some cases, they were not quite as effective (mainly on the higher rpm engines). That was using them as "direct supply" pumps. In some cases, we found better results simply running a 2oz tank as a header tank right behind the firewall, which was fed by a tank over the CG.

More recently I have been experimenting with the iron bay regulator and fully pressurized system, and also gathering some info using the perry pump with a return-loop system (works more like a fuel pressure regulator) similar to what the helicopter guys use. Results are promising, but I don't have enough data and flight time to claim a victory quite yet. Cold weather is setting in... not sure how much time I will get in testing over the winter.

As Dub likes to say... everything works once in a row. When you can duplicate the results consistantly a great number of times, then you are on to something. So I tend to error on the side of caution before making any official recommendations

If you wish to get more specific information on Dub's pump tests/experience on the 1.20, drop him a note directly at [email protected] and he will glady reply.

Bob

I am going to use the MVVS 91 with its long tune-pipe (they also have a short version) and a perry pump on a tai-ji 60 plane.
I will let you know about the performance results.

Regarding the MVVS 91, there are several silencer options: standard, quiet, dustbin and box. Noise is not an issue. Which silencer would give the best performance? I would like to use either the dustbin or box as they are in-cowl and wouldn't require modification of the fuse. Thanks.

Thanks guys, for the web address.

Bob, sounds like there may be 'more than 1 way to skin a cat'. I've run a ST2300 with a 2oz header tank with excellent results. I'm sure the external pump set-up would work well- it sure seems to on the OS 1.60FX.
Happy Flying,
Will

How does a header tank help? You still need to pull fuel from the main tank on the CG. Just wondering.

Yes, it does have to pull fuel from the main tank. In essence, the header/hopper tank gets filled from the main tank.

However the result of adding the header is that the engine is mainly only drawing fuel from the small tank (closer). As far as the engine is concerned, that is the level (distance) of the fuel tank. Another benifit is its drawing fuel (sucking) through a much shorter run of fuel tubing. Long fuel tube runs on a 'suck' system can be tricky. The header/hopper tank helps reduce the long run and distant tank effects. Also, the header tank tends to stay absolutely full most of the flight, keeping the clunk "wet" all the time.. no chance to grab an air bubble.

Yes, there are liquid levels/head pressure and stuff involved. Its not a perfect system. But it works.

You will see many of the helicopter pilots flying with a similar arrangment, for similar reasons. The fuel supply is effectively closer to the engine, and there is less chance of sucking air into the pickup line.

Note that you need something like a perry pump to feed the header tank from the main tank. If not, then the fuel draw is still effectively from the main tank back on the CoG.

Not entirely true. I use the header tank instead of the pump. For short term operation on vertical uplines. (20-30 seconds or less) the engine does not know the difference. However, you would not want to hover with it.

As I noted, yes, there is liquid level stuff involved. But this works.