Gary Arthur

My Feedback: (29)

After seeing the interesting results of my previous poll, [link=http://www.rcuniverse.com/forum/m_5106404/tm.htm]http://www.rcuniverse.com/forum/m_5106404/tm.htm[/link]
I would like to know how important it is to you that a manufacturer meet their advertised thrust/fuel economy?

Please select the one that best describes how you feel.

wojtek

My Feedback: (73)

i wonder what company’s rep voted on " not necessary" .... i think it is an absolute MUST !!! if an engine does NOT at least come close to the stated #s, i would ( as would the legal system ) consider it FRAUD and FALSE ADVERTISING.


Voy

joeflyer

My Feedback: (48)

Any product should live up to its advertised claims. Anything less reflects on the integrity of the manufacturer and his competence to produce a quality product.

There is certainly more to consider before making a purchase decision. I have used the turbine manufacturers data to compare alternatives, but I take it with a grain of salt because I know that some of it is exaggerated.

If a product performs better than expected the customer is very satisfied. If it fails to perform as advertised the customer feels cheated and wants it fixed. If it's a matter of exaggerated advertising claims I would question the manufacturer's honesty in other areas of business.

Joe

SAP_2000

Off course they should!

I think it is important that the people who get engines that doesn't meet the advertised specs. ship them back with either a claim of getting their money back, or having the engine meet the advertised specs without cheating (turning up the rpm etc.)

Informing the public via forums like this is a good remedy against performance fraud.
If more people did this, it would be harder for the manufacturers to cheat on performance figures.
And no one can convince me that they don't know excatly what their engines deliver of thrust and how much fuel they consume![>:]
IMO cheating with the figures is pure fraud!

Stick with the companies that are honest with their figures and provide a decent customer service.
Those two are often related.

WrenTurbines

To the people who do not think it is necessary:

Would you be happy if you bought a gallon of fuel and when you got it home there was only three-quarters of a gallon in the can?

Would you apply this sort of reasoning to everything you buy? If not, why should turbine engines be any different?

Sara Parish
Wren Turbines

digitech

My Feedback: (10)

go for it voy
for me i have nothing to worry about

siclick33

I find it odd that some people have answered 'it is not necessary' to this question.

If any of you that have voted this way could please contact me, I can do you a great deal on a 50lb thrust P80. I'll sell it for half the cost of a new P200

Gary Arthur

My Feedback: (29)

I've posted these polls in order to find out the facts regarding thrust/fuel consumption. I was not sure if it was only me that has experienced variances or if it was a common problem. As it turns out, I am not alone.

In the past I have purchased a few engines in various sizes and manufacurer's.

I bought;

Simjet 1200-14 that put out 14 1/2 lbs = HAPPY!
Simjet 2300 that put out 24 1/2 lbs = HAPPY! (Thanks Todd your engine is still alive!)
Simjet 700 that put out 7 3/4 lbs = HAPPY!
Wren 44G that put out 10 3/4lbs = HAPPY
My most recent purchase that is 2 1/2 lbs shy of advertised = UNHAPPY (Matt. No it's not a Jet Cat).

I have talked to the manufacturer and there is a plan in the works to remedy the problem but it may take a while.

So to sum it up, I find these polls very interesting!

jetpilot

My Feedback: (48)

Quit hiding the manufacturors, it wont help you get any better service and it wont help any of us guys!!!
Scott

wojtek

My Feedback: (73)

Between the posts and the original poll, there is enough concrete user info for people to make their own educated decision ...


Voy

afterburner

My Feedback: (18)

Woj is right. You are only allowed to post happy good things here. Be negative or talk about a manufacturer in a negative way and it's like calling the guys in the black suits AKA the cleaner [8D]. The thread will vanish. Only the mfr is allowed to say they have a problem with a product.

Marty

Gary Arthur

My Feedback: (29)

The reason of these polls is not to slam any manufacturer. It is to gain public information. I have heard grumblings many times about my engine does not do this, or that etc. So here is a tool that can give the public their time to say whether they have had similar issues and how they feel about it. I am hoping that some good will come from this. Someone recently posted that this type of poll is good. That it will help to make manufacturers more accountable to their customers. If need be, they will do more engineering to ensure the numbers they have claimed are met on a regular basis. Lets keep this POSITIVE!

Have you ever heard the saying "If it's not broken, Don't fix it?" Well if you do not break it and make it better, someone else will! Here is an opportunity to make things better.

Also, as a famous person has said "Your most unhappy customer is your best opportunity for learning".

jetpilot

My Feedback: (48)

If I bought a Ram 1000 and I got a Ram 750 I would be pissed. Or is buying a Ram1000 and getting a Ram875 OK?
Scott

wojtek

My Feedback: (73)

who are the dim bulbs voting on "its not nececssary" ... must be confused reps of some sort ...

Gary Arthur

My Feedback: (29)

Not necessarily true. If someone buys an engine and is satisfied with a slightly lower than advertised thrust, but is entirely happy with the longevity and reliability, he is welcome to vote that way. That is the whole idea of voting. The poll will tell you how most people feel.

wojtek

My Feedback: (73)

I get it ... its like buying a box of LuckyCharms or CocoPuffs .... even I you get only 2/3 of a box full, it's all right as long I think its yummy ... i can understnd that ..


Voy

mr_matt

My Feedback: (10)

rhklenke

My Feedback: (24)

A number of people have told me that they are not getting the advertized 28 lbs from their P-120's. I have not tested mine, but I don't have any real reason to not believe most of them. I also believe that the P-120 is capable of producing 28 lbs at standard temps. and pressures and it probably doesn't take "heroic efforts" to do so otherwise, I believe that the Jetcat folks wouldn't have advertized them as such. I have no idea what testing Bob and co. do on their P-120's before they leave the shop and if they even measure the thrust or try at all to "tweak" it to get as high as possible.

What I can tell you is that it doesn't really matter to me. I have three of them and they all run like tops - dean nuts reliable, start every time, sound good, no maintenance required as of yet, etc. and they push my planes - even my overweight Eurosport - around to my complete satisfaction. If any of you guys want to get rid of yours, put them on RCU for $2500 and as soon as I have the $'s, I'll pick them up. My P-120's are like most of my OS piston motors - very well made, very reliable, smooth and easy to operate, but not the biggest mule in the shed, so what? The advantages outweight the slightly lower power output.

Now if I was in the market of a true 33-35 lb plus motor, that might be a different story. I'm not sure if I'd go for a Titan or not. They seem like good motors, but I'm not yet convinced that they have the reliability record of the P-120 and they are, even by manufacturer's specs. down on power from the Merlin and Rhino. I've seen a Merlin and even though it seems to have good power, it just doesn't get me excited - I can't exactly say why. I have yet to really see a Rhino run, but I'd have to investigate it more and really see one run several times before I'd go for one. The Wren XL200 looks very interesting and seems to be worth watching although I probably wouldn't be the first on the block to buy one.

The bottom line is, I think the manufacturers should be honest about the thrust ratings of their motors, and I think most are, but its not a fatal crime if every motor off the line doesn't produce the exact amount of thrust that the brochure states. Nor would I send it back or sell it if it doesn't. Its a total package deal and power is only one metric by which to judge a motor.

My 2¢

Bob

ghost_rider

My Feedback: (20)

Just like you can express your opinion, others can express theirs also. Because their opinion did not jive with yours are not grounds to start calling them names.

This is the type of thing that sends some of the posts here to the never...never land.

Mark H

So to sum it up, I find these polls very interesting!
It is a shame that the first poll was shut down. I did not vote have owned many engines i have been pleased how they have flown in my planes. The main thing with a turbine that is designed to be flown ,that it is still running on landing . I have seen many turbines come a part in the air and no big thing is made of it! i have seen many stop and some run out of fuel, this is fault of the Dullard on the sticks not taking notice of his caller or timer . Most turbines today develop enough power to fly the model they are in unless the same Dullard has chossen the wrong power plant. How do you choose? the numbers on the box are your only Guide. I,m sure if you go back to the producer of the engine they will sort out the problem for you.However with some manufactures this could take a while. So on the First poll where do we mark for service satisfaction. Power and fuel consumpsion are not every thing!!!!
Mark Hinton {Team Hammer}

JONATHAN G

mark would it be like saying that the weight that your turbine you tested at the gtba and the one they tested in rcji dont add up it , seems the one you put on the scales was lighter, dont no why, are they not all the same when they leave the factory you would think regards jetman

Gary Arthur

My Feedback: (29)

I have been taking some heat since I posted these polls. To clear the air;
I am not complaining about any manufacturer.
I am not saying that any one manufacturer is putting out engines under spec.
I am not complaining about my most recent engine purchase. The manufacturer has already agreed to remedy my issue. Besides, I have bought 4 engines from various manufacturers prior to this and all have been at or above the stated thrust. So one engine a little bit low is no big deal.

Through my travels ( I travel a lot) and the people I meet, I have heard time and time again that various engines do not perform up to spec. A few recent posts have also touched on this subject. Nobody seems to mention it, yet it is on alot of peoples minds. This is the reason I have asked (by means of these polls).

1. If your engine meets spec.
2. Do you feel it should.

Simple and yet not so simple.

So that as a group, if we do feel this is an issue we can be heard. From what the polls tell me, there is a widespread issue and we do feel it needs to be addressed.

Mark H

Manufacturers are continuously making improvements on their product, If i had weighed the motor at the GTBA event i would have seen it weighed 16.5 Kg as it was installed in the star fighter! where they got the published weight from i do not know. I do not know any thing about the testing, only that i had been invited up to the event so i drove 180 miles to get the motor tested so people( like you) could see that it does produce 16.5Kg of thrust at 123000 rpm; Graupner Print 16.5kg at 123000 I am very pleased with this engine. Mine produced 17.4 kg at 123000rpm. Enough said!! Sorry Jetman you did not sign your post who are you? What engine do you fly? When did you last fly? Should I know you?
Mark Hinton {Team Hammer}

digitech

My Feedback: (10)

i drove 1000 miles (20 underground) and got no result..........
a well Mark it does not matter..
i have also tested the Hammer last summer i was "happy"
as you know most turbines run great when its cold , ours before it died (gtba ) did a amazing 14,5 kilos while it is advertised as a 130+ engine.
the weight of the engine is indeed fixed.
but i think i understand what jetman means.
if you look in the RCJ page 23 there is a advertisement of the engine with 410ml consumption and 1410 grams of weight.
if you turn that page over
the weight gained to 1674
and consumption goes up to 652ML.
the thrust rate looks ok , since i dont now the location or temps.
however on the GTBA results they show similair numbers exept the weight.
there must have been a mistake or your second engine lost weight? (1560 Gram)
i think this is what he tries to say.
however let us not use the GTBA to test our engines , as i believe it was originated for home users and builders.
for me it was a small vacation and meet people this was the most important for me.
my engine blew up due to lack of lubrication , do i care? no it was a pitty that i could not test the engine more overthere.
everyone was helping everyone . Wren , Artes does not matter we all helped each other.
so now back to testing , like Wren mentioned it is not nice as a manufacturer to read numbers as advertised that dont match up in real life.
the best thing would be as i also suggested on the last GTBA meeting is to measure the engine complete installed weight.
then only you will have a real thrust to weight ratio.
since the airframe is the same exept the powerplant you put in.

this is no basching!
i think all engines that live up to their specs are good engines.

WrenTurbines

There is something very interesting about fuel consumption figures, and since all this information is in the public domain and I'm going to use as an example an engine size -160N - that we don't yet produce, I don't think I'm out-of-order in collating the information here.

Fuel consumption figures show how efficient an engine is - the less fuel it burns for a given amount of thrust, the better. In practical tems for the pilot it means more flying time/less money spent on fuel.

Here are the fuel consumption figures for some of the 160 engines, all in ml/min, all except one at full throttle and taken from their websites:

JetCat 160 (from JC Germany's site) 510
Rhino 520 AVERAGE (makes it difficult to compare but full throttle will be considerably more)
Simjet Nexus 550
Merlin 622 (Website has a complete page of fuel/thrust statistics - very useful)

Sandor has noted above the figure in the current RCJI Graupner advert
Graupner Booster 410

Great! the Booster is clearly a much more efficient engine than any other. That must be the one to buy..;.

But hang on a moment, turn the page in RCJI and .... the review gives the figure as a huge 652! Over 50% more than claimed. It's suddenly gone from the best figure of those above to the worst.

This is why we always advocate that customers try to get independent information. It's interesting that the Merlin appears to have higher figure than all the others, yet it won the GTBA efficiency competition two years ago. If the other engines are so much better, why weren't they there? Unfortunately I don't have any independent figures to compare for those engines. (EDIT: I've just remembered that the Rhino entered the GTBA comp last month so have looked up the figures. It was doing 568 gram/minute. To convert to the ml/min I'm using for these comparisions we divide by 0.87 which is the specific gravity of fuel. That gives us 653 ml/min at full throttle, but it was doing over the 16kg at 17.5kg so at 16kg the figure would be a little less.)

You have shown in this poll that huge majority of fliers want to see accuracy from the manufacturers. So do we. We realised a while ago that there was a problem when a guy at a jet meet came up to our booth and said "I was thinking about one of your engines but I've gone with the XX because it has much better fuel consumption." That's odd, we thought ... we hadn't realised that company were so much in front of us with efficiency. So we went to their website where we saw the figure for their engine - 190ml/min as compared with the MW54's figure of 230. Looks much better ... but then we found two magazine reviews which gave the figure as 275 and 285. The MW54 review figure was 237 ( RCJI Oct 05). Which looks better now? We lost a sale over that ... and how many more sales that we didn't know about?

I have to reiterate: we are not against competition at all. We are happy to compete with other companies on FAIR TERMS. I hope everyone understands that. It has been hinted at in recent posts that people should not be bothering with advertising standards, it's not important. We think the fliers are helping themselves with this dicussion, and this is one manufacturer who has no objection at all to it.

Sara Parish
Wren Turbines