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Why isn't it called a P-105 RXi ?

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Old 01-06-2013, 10:57 AM
  #1
highhorse
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Default Why isn't it called a P-105 RXi ?

If or puts out more power than the 100, why give it a model number that implies it makes less?

This isn't keeping me awake at night, but I'm curious. Anyone have a solid answer?

Thx,
Don.
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Old 01-06-2013, 11:16 AM
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Default RE: Why isn't it called a P-105 RXi ?

I would think it's only conservative ratings to cover for variations on output for each individual engine, plus you also have variations due to altitude etc, this would have the actual output close to the rating and if possible never less than the rating . Or it could be so that JetCat buyers will not get disappointed just kidding, as far as I have seen every manufacturer does the same...
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Old 01-06-2013, 11:17 AM
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Default RE: Why isn't it called a P-105 RXi ?

Nothing against Jetcat...I think they are great engines but didn't they get caught a few years ago with the 120 not producing the thrust they claimed. Maybe they are playing it safe this time and giving min thrust numbers instead of max thrust numbers like most of the other manufacturers.
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Old 01-06-2013, 11:19 AM
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Default RE: Why isn't it called a P-105 RXi ?

Same goes for the P200 which is 230N

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Old 01-06-2013, 11:20 AM
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Default RE: Why isn't it called a P-105 RXi ?


Quote:
ORIGINAL: Jeremy300

Nothing against Jetcat...I think they are great engines but didn't they get caught a few years ago with the 120 not producing the thrust they claimed. Maybe they are playing it safe this time and giving min thrust numbers instead of max thrust numbers like most of the other manufacturers.

can't be that as they still quote the higher figure in the specs.

Jason
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Old 01-06-2013, 12:34 PM
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Default RE: Why isn't it called a P-105 RXi ?

As far as I know, it is only a model number representative of a thrust class, not necessarily a thrust rating. Not all engines are equal.
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Old 01-06-2013, 12:38 PM
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Default RE: Why isn't it called a P-105 RXi ?

+1 why is donkey called a donkey and not a horse, and a horse called a donkey. Its only a number, Only a name. What does count is that number after the word thrust.
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Old 01-06-2013, 01:34 PM
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Default RE: Why isn't it called a P-105 RXi ?

When the turbine was first developed (in case pump and valves etc) with was going to be set under 100N. The P80SE produced way more than 80N but it was still called a P-80. The P-90RXi is much heavier than a P-100RX, so power to weight its probably a little behind...
The higher power is from the higher RPM setting over the old P-80 types. Guess a P-80SE could be set to the same thrust cranked at 130,000

Its just a number Real world with all our turbines is a different thing altogether

Dave
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Old 01-06-2013, 02:14 PM
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Default RE: Why isn't it called a P-105 RXi ?

Just for understanding how thrust is measured. 100 Newtons of force equals 22 lbs thrust / 1lb. force = 4.55 newtons / 1kg. force =10.04 newtons.

Most manufactures started using this to give a designation to their engines. IE "P-80 = 17.6 lbs thrust" / "Kingtech-140 = 30.8 lbs thrust"
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Old 01-06-2013, 03:01 PM
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Default RE: Why isn't it called a P-105 RXi ?

I could be wrong, but if 1 Newton =0.224808943 to my calculation.[/b]
Than going by the calculations on what the number on the turbine is it will be this
P80 =17.9
Kingtech 140 =31.4 which is advertised at 31 pounds of thrust.
Correct me if I'm wrong.
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Old 01-06-2013, 05:24 PM
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Default RE: Why isn't it called a P-105 RXi ?

You're right. Or the way I prefer to remenber it is 1 lb. force = 4.448 newtons. Which means that 100 newtons = 22.5 lbs. Also 1 kg. force = 9.807 newtons.
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Old 01-06-2013, 05:44 PM
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Default RE: Why isn't it called a P-105 RXi ?

Personally, I wouldn't get too hung up on the naming convention equalling the tested thrust output. My BF Turbines B100 puts out 127.6N according to the test certificate that accompanied the purchase. And I'm Ok with that.
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Old 01-06-2013, 07:38 PM
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Default RE: Why isn't it called a P-105 RXi ?

Ok I was not exact on the #'s. Guess I should have googled it first " did not expect riddicule". I was just giving an explanation for newbie onlookers trolling through postings.
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Old 01-06-2013, 07:52 PM
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Default RE: Why isn't it called a P-105 RXi ?

Hello TimD,
was not trying to put you down friend.
The whole reason I jumped on and rectified it so when newbie's jump on they can get more accurate information.
I hope that some one will do the same to me if I post information which was not correct.
My apologies is you felt offended.
Ivan
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Old 01-07-2013, 07:20 AM
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Default RE: Why isn't it called a P-105 RXi ?

RXI refers to the Pump being installed in the front housing. Not just the valves.
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Old 01-07-2013, 07:26 AM
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Default RE: Why isn't it called a P-105 RXi ?

maybe you´re such a better pilot than me,but i can´t feel the difference from 100 to 105 on the sticks.do you? LOL.
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Old 01-07-2013, 07:30 AM
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Default RE: Why isn't it called a P-105 RXi ?

robersteam I agree.
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