Merlin 140 VS JetCat 140 VS Kingtech 140
 

Hi guys,

Yesterday my P80se had a catastrophic failure during flight with my FeiBau Hawk 120.
The engine somehow stop at full throttle and start shooting flames 2 meter long behind the plane...
I land it safely just to find out that the engine dead... I will send it to jetcat, but now it's the time to go bigger.

So, after looking around it came down to the last three: Merlin 140, JetCat 140 and Kingtech 140 (Or maybe 180 limited to 30Lbs ?)

What do you think ???

http://www.rcuniverse.com/forum/atta...mentid=1950127

Those are all superb engines, my personal choice in this class is Jet Central Cheetah, equally as good as the others but, with by far the best warranty. Maybe Jet Central is not available in your part of the world?

BTW, don't let Jetcat tell you that your P-80se is the only one they've ever seen blow up. Mine oversped and blew up twice. At the time they told me, mine was the only one they'd ever seen do that, ya right! :(

Mike

The new Merlin 140 with brushless starter motor and pump is my next turbine! The support Gaspar gives is also one of the reasons. He answers technial issues/matters within minutes/hours (he even answers email on sundays). My second choice would be Kingtech. My choice is based on my own experience with jetcat/evojet/merlin/behotec/BF turbines.

Ok,
After some more research, it's down to Merlin and Kingtech. No Jetcat for me... Too many problems around me with them... And the customer support is no mach to KT or Merlin.

I just went through this & bought the Kingtech K180G. When I bought my P-100, I loved it but wished I had spent the extra & went with a P-140RX. Now that I was in the market for a new turbine I decided to go with a 180 size so I can power bigger birds also. My buddy cashed & twin P140RX 20K aircraft TWICE due to P140 flame outs, so I decided to give JetCat a break. Also a 180 tuned down in theory will last forever.
Jay

I also saved my friend's SM Dragon twice due to P140 flame outs... One of the reasons to leave Jetcat aside.

I own two Merlins and am happy with both. I bought a M140 last year. It's small and light and has great fuel consumption. Now I wish I had waited for the M140XBL. By the way the M140 and Jet Central Cheetah are the same engine internally, designed by Gaspar. The M140XBL has internal solenoids, brushless fuel pump and starter, and upgraded electronics. Plus you get to deal directly with Gaspar.

Best power-to-weight-to-price ratio goes to...

http://www.ultimate-jets.net/blogs/j...ur-application

and that's without taking into consideration the fuel consumtion which is about 15% lower on the Merlin.

I am sure you will be happy with either of the M140 or K140. However, bear in mind that apart from having equivalent thrust levels, they are quite different engines.

The K140 is in a KJ66 size can. It is a good bit larger, heavier, and slower revving than the M140.

K140 dia 113mm. ----------M140 dia 102mm
K140 engine weight 1650g.---------- M140 engine weight 1320g.
K140 max rpm 123k ---------- M140 max rpm 130k

The New M140x also uses the latest Xcoy electronics which includes brushless starter motor and pump etc. I believe this is the first turbine engine to offer this.

I own one of the first M140s produced and have had great service from it.. In my opinion, I think the little extra that the M140 costs over the K140 is worth it, just for the smaller size and weight.

Roger

K180G & power anything from your Hawk to an Ultra Bandit or HUGE Hawk, & do it all for the same price as the M140.. IMO, much more versatile power plant to have in your fleet, although I really like the M140's.

40lbs! "In thrust we trust"

And that is why I'm having some hard time to decide...
I will order by the end of this week, and it's look like Merlin!
It will be a great benefit to my Hawk to loose some weight and reduce the wing load little bit...

What about:
Idle thrust increased by 30%
Engine weight increased by 40%
Fuel consumption increased by 20%

I'm not a really big fan of up sizing just for the sake of it. Never loose the prospect that you'll have to land your model at some point. Coming in the flare 30% faster is a good recipe for bounced landing, high energy impact and premature airframe/ gear wear.
I'm sure you've seen that in your flight carrier before...

This is all discussed here:
http://www.ultimate-jets.net/blogs/j...ur-application

Thanks Oli, you seal the deal...
As I mentioned in my last post, lowering the wing load, specially in that model will be great, and that's before considering the idle thrust and fuel consumption.

BTW, I see in your profile pic the A4, here's my friend's little A4. very old model, but new for him (second hand, first flight): http://www.youtube.com/watch?v=y136-31XIgQ
I'm the camera guy, as always, no one filming me...

"Idle thrust increase by 30%" Not sure where you got this number, but I was told the difference between K180 & 140 was very negligible. Not saying you're wrong, but where did you get it?
"Engine weight increased by 40%", I'm not a big fan of can-to-can comparisons, you'd really have to go airframe specific to get the big picture. Design/wing area are the biggest factors when figuring your (percentage) weight increase & performance penalty factors.
"fuel consumption increase by 20%", If your numbers are right, good job, but how did you get them? You would have to take a K-180 & detune it to the same thrust as the M-140 them measure consumption over time. I haven't seen that done yet, so I don't have the necessary info to comment.
"Flare 30% faster" again, where do you get these figures? AIRFRAME SPECIFIC! a 30lb model increasing to approx 31lbs (turbine weight difference) is a 3% increase. The only experience I have with that is full scale, & I can tell you the difference between landing speeds with a 3% increase is almost unnoticeable.
I think the OP will love his new M140 (not trying to talk him out of it), but in the event he decides it's time to try that large Ultra Lightning, or Skymaster, or runs into that good deal in the classifieds, he will have to come better than 31lbs thrust. Maybe he already has a big block in his fleet, in that case I would love the small efficient M-140 (it may be my next turbine..lol)

Oli,

A 30% increase in idle thrust causing a 30% increase in landing speed is some of the most egregious disinformation I have seen posted here in a long time,and I'm surprised you posted it.

Jay covered the basics of it above,but beyond that,the airframe type is also an important consideration. A clean sport jet will be much more affected by higher idle thrust than an F-4 or F-18 ,that is flown down the final with power,at higher AOA's.

As as to the OP,I am on my third Kingtech engine. I currently own 2 180G's,and have been extremely happy with the quality,support,and value of them. Bottom line,it's nice to have a choice between 3 quality engines. Good luck,

Erik

OTE=olnico;11691294]What about:
Idle thrust increased by 30%
Engine weight increased by 40%
Fuel consumption increased by 20%

I'm not a really big fan of up sizing just for the sake of it. Never loose the prospect that you'll have to land your model at some point. Coming in the flare 30% faster is a good recipe for bounced landing, high energy impact and premature airframe/ gear wear.
I'm sure you've seen that in your flight carrier before...

This is all discussed here:
http://www.ultimate-jets.net/blogs/j...ur-application[/QUOTE]

Don't be surprised since I didn't post that. Read again...

RCJI, turbine test special.

He got it.

Yep,

BTW, I'm waiting for a bigger Kingtech for my next project, the Skygate Hawk.

Really Oli? "Coming in the flare 30% faster....". I'm not sure there are many other ways to interpret that. You make valid points,and I respect your opinion,but that is bad information,that would definitely be misleading to someone with little experience or knowledge. Happy,safe holidays to you and yours.

Erik

Yeah, IMO a bunch of mis-info in post #12. I have the RCJI comparison issue, & don't think there is a way to interpolate most of the figures you (Oli) have provided. Snir2001, we are in the same boat..lol I have an Ultra Flash my K180 is going in for now (can handle the extra weight), but the K180 was really purchased for a future Skygate Hawk, but FYI Anton from Skymaster told me he will be releasing a 125" long 3.2m Hawk end of 2014, so I'm holding on the Skygate until I see that.
For the record, I completely agree with Oli in saying the M140 is a better match for your current platform, but sometimes there is more to the equation.
Good luck, I like the way you think..haha:)

Regardless of manufacturer, if you go with the larger hawks or Ultra Bandit you'll want a 200+ motor. 180 will fly it, but the vertical will be marginal.

Hi George,

I was referring to the MAXIMUM RPM of the engines, not the ACCELERATION time.

The M140 is smaller, but spins faster then the K140.

I did not mean to suggest that the M140 ACCELERATED any faster than the K140. :)

Roger

Sorry my mistake